known to have Type 2 diabetes. appears to be relatively very low needs of people with diabetes in Ethiopia and report on a …

Chapter 31

Diabetes in African Americans
Eugene S Tull, DrPH; and Jeffrey M Roseman, MD, PhD, MPH
SUMMARY

mong US black children age 15 years, estimates of insulin-dependent diabetes mellitus IDDM incidence from population registries range from 33 to 118 per 100,000 per year The almost fourfold variation in IDDM incidence may result from differential exposure to etiologic agents, differences in susceptibility due to white genetic admixture, and differing genetic and autoimmune phenomena including HLA, islet cell antibodies, and frequency of Asp-57 In contrast to diabetes in adults, the incidence of diabetes in children predominantly IDDM is lower in black than in white Americans Rates for white American children are nearly twice as high as in blacks, ranging from 138 to 169 per 100,000 per year Based on the 1993 National Health Interview Survey NHIS, the prevalence of known, physician-diagnosed diabetes among African Americans is 37, rising from 13 at age 0-45 years to 174 at age 65-74

years The rate of diabetes in blacks has tripled during the past 30 years Prevalence of diagnosed diabetes in adults is now 14 times as frequent in blacks as in whites This excess occurs for
both black men and black women Approximately 13 million African Americans have been diagnosed as having diabetes In addition, based on the 1976-80 Second National Health and Nutrition Examination Survey NHANES II, approximately half of both black and white adults who meet diagnostic criteria for non-insulin-dependent diabetes mellitus NIDDM are undiagnosed The frequency of diabetes in black adults is influenced by the same factors that are associated with NIDDM in other populations, including obesity, physical inactivity, insulin resistance, and genetic factors Data on the frequency of diabetes complications in African Americans are limited but suggest that this population experiences considerable morbidity and excess frequency of many diabetic complications

INTRODUCTION

black Caribbean populations are provided
CLASSIFICATION OF DIABETES

In recent years, there has been much concern about the excess frequency and complications from diabetes in minority populations in the United States In 1986, a Task Force on Black and Minority Health called attention to limitations in knowledge about diabetes in minorities and the need for increased research and intervention to
reduce the excess burden of diabetes in these groups1 In this chapter, data on the frequency of diabetes and associated risk factors in the black population of the United States are reviewed and implications for this ethnic group are discussed The African-American population includes many individuals who have immigrated to the United States from other parts of the Americas, particularly the Caribbean, for whom little is known of their diabetes status Thus, whenever possible, data on diabetes in
613

Epidemiological studies conducted to assess the impact of diabetes in black populations have examined a number of syndromes of glucose intolerance, some of which appear to be more common in black than in white Americans These include NIDDM, the major form of diabetes affecting all populations in the United States, IDDM, impaired glucose tolerance IGT, gestational diabetes mellitus GDM, and the malnutrition-related diabetes subtypes described by the World Health Organization WHO 2 as proteindeficient pancreatic diabetes PDPD and fibrocalculus pancreatic diabetes FCPD Other atypical diabetes syndromes characterized by

Table 311

Diagnostic Criteria and Description of Diabetes
Subtypes
Type of diabetes Diagnostic criteria Description

NIDDM FPG 140 mg/dl Also termed Type 2 diabetes; 2-hour OGTT 200 mg/dl usually develops after age 40; associated with obesity and family history of diabetes IDDM FPG 140 mg/dl Also termed Type 1 diabetes; 2-hour OGTT 200 mg/dl abrupt symptoms; insulinopenia and ketosis; may have subclinical period lasting many years; associated with HLA and autoimmunity FPG 140 mg/dl Diabetes during pregancy 2-hour OGTT 200 mg/dl with return to normal glucose status after delivery; associated with increased risk of developing NIDDM FPG 140 mg/dl 2-hour OGTT 140-199 mg/dl Increased risk of developing NIDDM; high frequency of cardiovascular risk factors

GDM

are formed by environmental and genetic influences that change throughout history To understand how rates of diabetes vary among African Americans, it is important to examine the historical origins of black populations in the Americas To a great extent, the sociodemographic characteristics that influence diabetes rates in African Americans have been shaped by the dynamics of European colonialization in the Americas African Americans are descended from Africans whose parent populations
were characterized by much cultural and genetic diversity13 The ships that brought Africans to the Americas contained individuals from a variety of ethnic groups of West and Central African origin Figure 31114-16 However, because of the system of slavery, ethnic distinctions did not persist in the New World14 Thus, the AfricanAmerican population became a hybrid population formed from genetic admixture across African ethnic groups and with other racial groups, primarily European and North American Caucasians17 Today, variations in the degree of European admixture exist across African origin populations in the Americas18-20 and by region within the United States17 Similar differences in culture have emerged that contribute to the environmental and lifestyle factors that influence variation in rates of diabetes in African-American populations The African-American population includes many individuals who have immigrated to the United States from other parts of the Americas, among whom cultural beliefs may influence lifestyle factors such as dietary behavior, physical activity patterns, and attitude toward body size and weight

IGT

PDPD

FPG 140 mg/dl Cases present very thin;
resis2-hour OGTT 200 mg/dl tant to ketosis; shows phasic insulin dependence FPG 140 mg/dl Characteristics similar to PDPD but with pancreatic calcification

FCPD

FPG, fasting plasma glucose; OGTT, oral glucose tolerance test; GDM, gestational diabetes mellitus; IGT, impaired glucose tolerance; PDPD, protein-deficient pancreatic diabetes; FCPD, fibrocalculus pancreatic diabetes Diagnostic criteria are those recommended by the World Health Organization; other criteria for GDM more commonly used in the US are based on a 3-hour OGTT and are described in Chapter 2 Source: References 2-12

resistance to ketosis and periods of normoglycemic remission with subsequent hyperglycemic relapse have been described in black populations These include atypical maturity-onset diabetes of the young MODY in African-American children 3 and the diabetic syndrome of phasic insulin dependence in Jamaica4 Similar atypical diabetes syndromes have been reported in the United States5 and Africa6 Diagnosis and classification of these diabetes subtypes see Chapters 2 and 5 are based on criteria of the National Diabetes Data Group NDDG7 and the WHO8 A summary description of the different forms of diabetes is
presented in Table 3112-12

Figure 311

Origin of African Americans from West and Central Africa

North America Africa South America

HISTORICAL ORIGINS OF AFRICAN AMERICANS
Source: References 14-16

The sociodemographic characteristics of populations
614

Figure 312

Incidence of Childhood IDDM in US Black and White Populations
20 Allegheny County, PA Jefferson County, AL Philadelphia, PA San Diego, CA

Black

White

Source: References 23-26

INCIDENCE OF DIABETES IN CHILDREN

rates of IDDM in African-American children was first suggested by MacDonald29, who observed that black American children had a frequency of IDDM that was lower than white American children but higher than black African children He hypothesized that rates of childhood IDDM were higher in African-American than in black African children because IDDM susceptibility genes, which are more common in the US white population, had become admixed into the African-American gene pool Studies using genetic markers30-32 and ancestral histories27 have provided support for this hypothesis When the association of European admixture with the frequency of childhood IDDM was assessed by grandparental race in the US
Virgin Islands, more admixture was found among those with IDDM than in those without diabetes, which supports the admixture hypothesis27 As with black populations in the United States, it is expected that the incidence of IDDM in African heritage peoples in the Americas will vary geographically, being influenced by environmental and lifestyle factors as well as the degree and type of European admixture33 It is possible that the almost fourfold variation in incidence seen in black children in IDDM registries in the United States, as well as gender differences, might result from differential exposure to etiologic agents Another possible explanation is that the geographic variation might reflect differences in susceptibility due to white genetic admixture This would be consistent with the observation that the incidence 118 per 100,000 per year of childhood IDDM among African Americans in a northern area like Allegheny County, PA, where the degree of white admixture is 212, is higher than the incidence 44 per 100,000 per year in a southern location like Jefferson County, AL, where genetic admixture is 17923,24,30,34

In contrast to diabetes in adults, the incidence of diabetes in
children predominantly IDDM is higher in white than in black Americans21,22 Among US black children age 15 years, estimates of IDDM incidence from population registries range from 33 to 118 per 100,000 per year Figure 31223-26 Corresponding rates for white Americans are nearly twice as high, ranging from 138 to 169 per 100,000 per year A racial difference also exists in the distribution of cases by gender, with a female excess in black children compared with a slight male preponderance in white children There have been few reports of the frequency of childhood diabetes in other black populations in the Americas An IDDM incidence of 56 per 100,000 per year for children age 0-14 years was found in the US Virgin Islands27 The incidence at age 0-14 years on the island of Barbados was reported to be 41 per 100,000 per year28 One report suggested that the incidence of IDDM on Martinique was lower than 2 per 100,000 per year, but an actual rate was not provided19

HLA AND IDDM IN AFRICAN AMERICANS
Possible genetic factors that admixture may have increased are genes in the major histocompatibility region the HLA complex of chromosome 6 Genes of this complex are involved in immunological
rejection of foreign cells and synthesis of complement components35 There is a strong association between the presence of HLA antigens, particularly DR3 and DR4, and the development of IDDM in a number of populations36-38 The highest risk for IDDM is associated with HLA DR3/DR4 heterozygosity39 African Americans with IDDM have HLA DR allelic associations that are similar to those in US whites36,40,41 When HLA DR frequencies were examined in black Nigerian IDDM patients, an association with DR3 but not DR4 was found, as is characteristic of black and white Ameri615

RISK FACTORS FOR CHILDHOOD DIABETES IN AFRICAN AMERICANS

RACIAL ADMIXTURE
The importance of genetic admixture in determining

cans with IDDM42 Thus, the susceptibility determinant derived from admixture with Caucasians may be DR4 associated43 An amino acid substitution for aspartic acid at position 57 non-Asp 57 of the HLA-DQ beta chain was identified as a highly specific marker of IDDM susceptibility44 There is an almost 100 correlation of this marker with the incidence of IDDM in different ethnic populations45 The frequencies of these susceptibility phenotypes in the population vary among racial groups but tend to be
higher among European and North American Caucasians45,46 However, no significant difference was found between black and white patients with IDDM in Allegheny County, PA in the frequency of non-Asp57 homozygosity associated with the strongest risk of IDDM44 Relationships between HLA alleles and IDDM among African Americans that differ from other ethnic groups may provide important insight into the etiology of the disease47 Research on the association of HLA-DQ genes and HLA-DR7 and DR9, which are associated with IDDM in black populations but not in Caucasians, have provided evidence that both DQ A1 and B1 genes convey susceptibility to IDDM48,49 In black populations, the HLA-DQ A1/B1 combination A3, DQw2 may be an important marker of IDDM susceptibility49,50

Table 312

Percent of Persons Who Have Diagnosed Diabetes, US, 1991-92
Age years
45 45-64 65-74
75

1991 1992 Average, 1991-92 Black White Black White Black White
085 977 2194 1111 367 087 535 912 902 282 091 818 2232 1585 364 074 536 1044 992 291 088 898 2213 1348 366 081 536 978 947 286

Total

See Appendix 311 for 1993 prevalence rates Source: References 58 and 59

SOCIOECONOMIC STATUS
The relationship between socioeconomic
status and childhood IDDM appears to be weak Studies relating socioeconomic status to IDDM incidence have found positive54 and negative55 results and, in most research, no association at all24,56,57 Thus, it appears unlikely that racial differences in the frequency of childhood IDDM in the United States are significantly related to socioeconomic status

PREVALENCE OF DIABETES IN ADULTS

IDDM AND AUTOIMMUNITY
Differences in autoimmune phenomena associated with IDDM exist for black and white individuals with the disease The frequency of islet cell antibodies ICA and other organ-specific antibodies that characterize autoimmune beta cell destruction in IDDM is lower for black than white American cases ICA in 40 versus 60 of cases, respectively23,51 In Jamaica, ICA was not found in sera from 42 IDDM patients52 Similarly, only two of 24 sera from insulin-treated young Nigerian diabetic patients were ICA positive53 Diabetic syndromes resembling IDDM at clinical presentation but lacking the HLA associations occur in black populations and may possibly confound these ICA results However, the tendency to be less prone to ketosis and show lower frequency of autoantibodies may indicate that
black populations manifest a different form of IDDM from that which occurs in white individuals52 Additional research is needed to determine the reasons for the apparent differences in manifestations of autoimmune phenomena in black and white Americans with IDDM

Data on the rate of diagnosed diabetes in black and white adults based on the 1991-92 NHIS are shown in Table 312 and Figure 31358,59 At age 45 years, the prevalence of known, physician-diagnosed diabetes is 14 to 23 times as frequent in blacks as in whites This
Figure 313

Prevalence of Diagnosed Diabetes Among Blacks and Whites, US, 1991-92
25 Whites 20 15 10 5 0 Blacks

All Ages

45-64 Age Years

65-74

7 5

See Appendix 311 for 1993 prevalence rates Source: References 58 and 59

616

Figure 314

Figure 315

Prevalence of Diagnosed Diabetes Among Black and White Males and Females, US, 1989-91
25 20 15 10 5 0 White males Black males White females Black females

Prevalence of Undiagnosed and Diagnosed NIDDM and IGT in Black Adults, US, 1976-80
45 40 35 30 25 20 15 10 5 IGT Undiagnosed NIDDM Diagnosed NIDDM

Total

45-64 Age Years

65-74

7 5

0 20-44

45-54 Age Years

55-64

65-74

Source: References 59-61

IGT,
impaired glucose tolerance Source: Reference 62

excess occurs in both black men and black women Figure 31459-61 Approximately 114 million African Americans had been diagnosed as having diabetes in 1991-92 Table 313 In 1993, the rate increased to 41 and the number of African Americans known to have diabetes was 131 million Appendix 311 In the 1976-80 NHANES II, it was found that approximately half of both black and white adults who met diagnostic criteria for NIDDM were undiagnosed62 Total prevalence of diagnosed and undiagnosed NIDDM in adults in 1976-80 is shown in Figure 315 Prevalence increased with age and reached 25 of blacks age 65-74 years Rates were highest in black women, in whom one in four age 55 years had diabetes Table 314 Because the rate of diagnosed diabetes ascertained in the NHIS has continued to increase over time, it is likely that the NHANES II rates are low However, the excess prevalence in blacks versus whites seen in the NHIS is also seen when total prevalence of diabetes in NHANES II is examined62
Table 313

Estimates of the prevalence of diabetes from population-based studies of adult black Caribbean populations have ranged from 073 to 145; rates were
higher for females than males63-70 Unfortunately,
Table 314

Percent of Blacks and Whites Age 20-74 Years with Diagnosed and Undiagnosed Diabetes and IGT, US, 1976-80
Age years 20-44 45-54 55-64 65-74 20-74
Black males Diagnosed diabetes Undiagnosed diabetes IGT Total glucose intolerance Black females Diagnosed diabetes Undiagnosed diabetes IGT Total glucose intolerance White males Diagnosed diabetes Undiagnosed diabetes IGT Total glucose intolerance White females Diagnosed diabetes Undiagnosed diabetes IGT Total glucose intolerance 18 10 47 75 26 09 146 181 05 05 46 56 14 08 65 87 36 75 188 299 75 71 157 303 45 33 126 204 39 48 145 232 92 54 186 332 163 116 123 402 53 41 172 266 66 86 137 289 172 122 226 520 108 133 84 325 91 100 228 419 88 82 230 400 45 41 113 199 59 51 138 248 28 27 102 157 36 37 111 184

Number of Persons in Thousands with Diagnosed Diabetes, US, 1991-92
Age years
45 45-64 65-74
75

1991 1992 Average, 1991-92 Black White Black White Black White
200 475 353 106 1,134 1,218 2,175 1,489 981 5,863 216 408 367 155 1,146 1,033 2,238 1,710 1,106 6,087 208 442 360 131 1,140 1,126 4,413 1,600 1,044 5,975

Total

See Appendix 311 for 1993 prevalence rates Source:
References 58 and 59

IGT, impaired glucose tolerance; diabetes status determined by medical history and results of oral glucose tolerance test using World Health Organization criteria, 1976-80 Second National Health and Nutrition Examination Survey Source: Reference 62

617

many of these studies used varying population age structures and screening and diagnostic methods, such as glycosuria, which have low sensitivity63, thereby limiting comparisons among them However, given the variation in degree of economic development throughout the Caribbean islands, it is possible that large differences in diabetes prevalence do exist within the region It would be interesting to compare patterns of diabetes prevalence and risk factors between black populations in the United States and the Caribbean that are at various stages of economic development and epidemiologic transition

Figure 317

Prevalence of Diagnosed Diabetes by Sex and Race, US, 1963-90
5 4 3 2 1 0 Crossover Black male White male Black female White female

TIME TRENDS IN PREVALENCE OF DIABETES

1965

75 Year

Source: 1963-90 National Health Interview Surveys

Over the past 30 years, increases in the prevalence
of chronic diseases such as NIDDM and heart disease have occurred in societies where economic development has resulted in decreased infant mortality, increased life expectancy, and adoption of a Western lifestyle in place of more traditional living patterns71 Data from the 1963-92 NHIS in Figure 316 provide some evidence of the influence of this epidemiologic transition on the changing frequency of NIDDM among African Americans During this period, the percentage of US blacks who had been diagnosed with diabetes rose from 12 to 36 and the number of black Americans with diagnosed diabetes rose from 230,000 to 115 million Although there has been an overall increase in the prevalence of diabetes in the United States, the change has not been identical for both blacks and whites
Figure 316

Prevalence and Number of Persons with Diagnosed Diabetes in Blacks, US, 1963-92
45 4 35 3 25 2 15 1 05 0 1963 70 75 Year
Source: 1963-92 National Health Interview Surveys

From 1963-85, the rates of known diagnosed diabetes doubled for whites but tripled for black Americans Figure 317 An intriguing pattern emerges when these data are examined by sex and race During 196385, diabetes rates for black
females were consistently higher than rates for white females Black males, however, had a lower rate than white males until 1973 After that year, there was a reversal such that the rate for black males became slightly higher than the rate for white males It is possible that this crossover represents a true increase in the prevalence of diabetes among black males, with this change possibly being brought about by a concomitant increase in the prevalence of diabetes risk factors in the black male population On the other hand, the observed pattern in diabetes prevalence for black males might only reflect an increase in the proportion of diagnosed to undiagnosed cases Another possibility is that the increase in diabetes prevalence among black men resulted from increased survival, rather than an increase in the underlying rate of diabetes occurrence

1,200 Percent Number

INCIDENCE OF NIDDM
1,000 800 600 400 200 0 92

Additional evidence of the increased frequency of NIDDM in blacks in the United States is available from incidence data of the Epidemiologic Follow-up Study of the 1971-75 NHANES I The patterns of race-sex differences in diabetes incidence were consistent with NHIS
prevalence data Of 11,097 individuals age 25-70 years in 1971-75 who were followed to 1987, 880 were diagnosed with diabetes The age-adjusted incidence of diabetes diagnosis was 15 for black women, 109 for black men, and 70 and 69 for white men and women, respectively72
618

NIDDM RISK FACTORS IN AFRICAN AMERICANS

Table 315

Obesity in Blacks and Whites Age 20-74 Years, by Diabetes Status, US, 1976-80
Black White

A combination of factors, including lifestyle changes associated with the improving economic conditions of African Americans such as changes in diet, levels of physical activity, patterns of obesity, together with longer life expectancy and increased genetic susceptibility, may account for the observed racial patterns in diabetes prevalence over the past 30 years This is only speculation, however Unlike other nonwhite populations in which there is evidence of the relationship between economic development, lifestyle changes, and increased rates of NIDDM73, little is known about changes in risk factors or diagnostic methods that may have precipitated the dramatic increase in the prevalence of NIDDM among African Americans The frequency of NIDDM in the African-American
population is influenced by individual characteristics such as age and sex, which have been discussed above Other factors associated with an increased risk of developing NIDDM include genetics and lifestyle factors such as socioeconomic status, obesity, and physical activity

Men Women Men Women
Previously diagnosed diabetes Newly diagnosed diabetes No diabetes percent with PDW 120 445 834 392 623 644 781 385 787 321 558 272 350

PDW, percent desirable weight; diabetes status determined by medical history and results of oral glucose tolerance test using World Health Organization criteria, 1976-80 Second National Health and Nutrition Examination Survey Source: Reference 80

which relates weight in kilograms to height in meters squared or as percent desirable weight PDW based on the Metropolitan Life Insurance tables In the US population, rates of obesity BMI 273 for women, 278 for men are higher for African-American women compared with white women, white men, and black men79 The close association of obesity with diabetes can be seen in Table 315, where data from respondents age 20-74 years in the NHANES II cohort show the prevalence of obesity PDW 120 among diabetic black men and
women to be substantially greater than their nondiabetic counterparts80 In addition to the degree of overweight, regional distribution of body fat truncal versus peripheral is also associated with increased risk of developing NIDDM, with the risk being greater for individuals with truncal central obesity81 Thus, it is possible that a greater tendency for African Americans to store fat centrally82, together with high rates of total obesity, may partly explain their higher prevalence of NIDDM compared with white Americans The excess risk of NIDDM in blacks relative to whites increases with increasing level of obesity, particularly for black females72,83 Obesity cannot account for all the excess prevalence of NIDDM in black compared with white Americans, however Rates of diabetes are higher for African Americans relative to whites, even after controlling for age, adiposity, and socioeconomic status83,84 It appears that other factors, such as genetics, contribute to the observed racial differences in the frequency of NIDDM in the United States

GENETICS: THE THRIFTY GENE HYPOTHESIS
Neel suggested that populations exposed to periodic famines, which occur in Africa, would through natural
selection increase the frequency of certain genetic traits, thrifty genes, which would protect against starvation during times of famine74 These genes would allow for efficient energy conservation and fat storage during times of abundance In circumstances of relative plenty, as in the United States in the absence of feast and famine cycles, these genes would become disadvantageous, predisposing to the development of obesity and an increased frequency of NIDDM The higher rates of diabetes and obesity in African Americans and urban Africans compared with black Africans in traditional environments is consistent with this hypothesis75 An active search for NIDDM genes is being conducted see Chapter 9 for a detailed discussion

OBESITY SOCIOECONOMIC STATUS
The association of obesity as a major risk factor for NIDDM has been established in many ethnic groups, including African Americans76-78 In most studies, obesity is usually measured as body mass index BMI,
619

In the United States, an inverse relationship has been noted for socioeconomic status education and income and the prevalence of diabetes in adults for

both black and white Americans Data from the NHIS show that for both black
and white Americans diabetes frequency decreases with increasing level of education and family income85 However, rates for the African-American population are higher than for whites at each level of education and income If age and obesity are controlled for, the association of income and education with NIDDM prevalence is significantly reduced80,83 Thus, whether socioeconomic status has any direct role in the etiology of NIDDM is unclear

PHYSICAL ACTIVITY
Physical inactivity is an independent risk factor for NIDDM, and physical activity is a strong protective factor against the development of NIDDM 86,87 However, data on levels of physical activity based on validated measures are not available for the AfricanAmerican population Given the general inverse relationship between physical activity and obesity, it is likely that, relative to black males and white Americans, African-American females have lower levels of physical activity, which may contribute to their higher rates of obesity and diabetes It is important that studies using validated measures of activity88 be conducted on representative samples of African Americans to evaluate the role of physical activity in the
development and prevention of diabetes in the black population

women at age 55 years92 If IGT is a stage in the natural history of diabetes, then higher rates of NIDDM risk factors such as obesity among black females may contribute to this decrease by precipitating rapid conversion of IGT to overt diabetes92 However, comparison of the rates of total glucose intolerance IGT plus diabetes for the race-sex groups shows that the total intolerance rate remains lower for black females at age 65-74 years This suggests that conversion from IGT to diabetes cannot completely account for the age pattern of IGT rates seen in black women92 One possible explanation for the decrease in IGT rates for black women at age 55 years is increased mortality in the older age groups80 However, further research in this area is needed

ATYPICAL DIABETES

INSULIN RESISTANCE
Elevated levels of fasting insulin are associated with an increased risk of NIDDM89 Hyperinsulinemia can predate the development of diabetes for years90, and black adolescents are more hyperinsulinemic than white children91 Although insulin resistance characterizes several atypical diabetic syndromes occurring in African heritage
populations4,5, there are no prospective data on the relationship of insulin resistance and/or hyperinsulinemia to subsequent development of NIDDM in African Americans Clearly, more research is needed in this important area

Atypical diabetic syndromes that display insulin and ketosis resistance and intermittent periods of normoglycemic remission have been reported in AfricanAmerican patients4,5 An insulin-resistant variant of NIDDM associated with HLA-DQW7 has led to suggestions that NIDDM in African Americans occurs in insulin-sensitive and insulin-resistant forms that differ genetically93,94 An atypical diabetes that presents with features of IDDM but lacks the characteristic HLA associations has been found in young African Americans3 This syndrome may be more common in black than white Americans95 and may account for 10 of cases of youth-onset diabetes among African Americans in the southeastern United States In the Caribbean, a ketosis-resistant diabetic syndrome displaying phasic insulin dependence and associated with malnutrition has been described in Jamaica96 It will be useful to obtain population-based prevalence estimates of these atypical diabetes Future research into
the genetic basis for the occurrence of atypical diabetes among black populations in the Americas may provide important clues about the etiology of NIDDM

GESTATIONAL DIABETES

IMPAIRED GLUCOSE TOLERANCE
IGT, a category of glucose intolerance in which postchallenge values are between diabetic and normal, is a strong risk factor for NIDDM IGT rates are higher for black than white Americans Table 314 While IGT prevalence rates increase with age for black men, white men, and white women, they decrease for black
620

GDM is defined as glucose intolerance that develops during pregnancy and returns to normal tolerance after delivery Among 3,744 patients screened for GDM at Northwestern University Medical School, the relative risk of developing GDM was 181 95 confidence interval CI 113-299 for black compared with white women97

Figure 318

Figure 319

Percent of Birth Certificates Listing Diabetes in the Mother, US, 1991
8 7 6 5 4 3 2 1 0 20 20-24 25-29 30-34 35-39 Maternal Age Years 40-49 All Ages White Black

Prevalence of Retinopathy in Adults with Diagnosed NIDDM, Age 40 Years, US, 1988-91
40 Age years 40-59 60

Non-Hispanic White

Black

Mexican American

Source:
Reference 98

Source: Reference 104

The US birth certificate has a section in which diabetes in the mother can be recorded Figure 318 shows the percent of birth certificates in which diabetes was recorded98 However, it is not possible to determine whether the diabetes was IDDM, NIDDM, or GDM In addition, there may be underrecording of maternal diabetes on these records It is estimated that 50 of women who develop GDM will subsequently develop overt diabetes over a 20year period99 Among African-American women, risk factors for GDM include older age, gravidity, hypertension, obesity, and family history of diabetes100 These are also risk factors for GDM in other racial/ethnic groups

eyes have reported the prevalence of blindness secondary to diabetic retinopathy to be twice as high in black compared with white individuals103 The frequency of severe visual impairment has also been reported to be 40 higher among African Americans with diabetes than their white counterparts80 The prevalence of retinopathy in a sample of US blacks with diagnosed NIDDM in the 1988-91 phase of NHANES III was substantially higher than the rate in non-Hispanic whites but was similar to the rate in Mexican
Americans Figure 319104 Diabetic retinopathy may be more frequent among US blacks than whites because of higher rates of hypertension and inadequate metabolic control105

DIABETIC COMPLICATIONS IN AFRICAN AMERICANS

DIABETIC KIDNEY DISEASE NEPHROPATHY
Diabetes is the second leading cause of end-stage renal disease ESRD in the black population, accounting for 325 of new ESRD cases in 1988-91, with the leading cause, hypertension, accounting for 379106 During this 4-year period, an annual average of 4,036 new cases of diabetic ESRD occurred in blacks; the average number of black diabetic ESRD patients was 11,411 during 1988-91106 The increased frequency of diabetic nephropathy including ESRD in black compared with white Americans with diabetes ranges from 26 to 56 times excess107-110 However, it appears that survival after the development of ESRD may be better for black than white individuals with diabetes111 Prevalence of nephropathy among individuals with diabetes has been associated with hyperglycemia and hyperten621

Data on the frequency of diabetes complications in African Americans are limited However, evidence suggests that African Americans experience considerable morbidity
and excess frequency of many diabetic complications compared with the US white popula tion1,75,80,101

DIABETIC EYE DISEASE RETINOPATHY
Diabetic retinopathy, which is characterized by alterations in the small blood vessels in the retina, is the leading cause of new cases of blindness in the United States in individuals age 20-74 years102 Studies on the frequency of complications of diabetes affecting the

sion112 Therefore, it is possible that higher rates of these factors may contribute to the excess prevalence of clinically diagnosed nephropathy in diabetic African Americans

Table 316

Factors That Influence Risk of Diabetes Complications
Type of diabetes IDDM versus NIDDM; insulin-sensitive versus insulin-resistant Delay in diagnosis and treatment Socioeconomic conditions limited education, no insurance Personal lifestyle factors smoking, alcoholism, etc Psychosocial factors mental illness, denial of disease

AMPUTATION
Based on a sample of all hospital discha rges in the United States in 1990, the rate of lower extremity amputations was 82 per 1,000 diabetic population for blacks versus 69 per 1,000 for whites113

CARDIOVASCULAR DISEASE
African Americans with diabetes are
at increased risk of macrovascular disease, including heart disease and stroke, relative to those without diabetes114,115 However, the prevalence of cardiovascular disease in diabetic patients appears to be lower in blacks than in whites The frequency of angina and myocardial infarction in the 1976-80 NHANES II cohort was 23 and 30 times as great among newly diagnosed diabetic whites, and 50 and 20 higher, respectively, among previously diagnosed diabetic whites compared with diabetic African Americans80 Most diabetic African-Americans may have an insulin-sensitive form of diabetes that is associated with reduced levels of cardiovascular disease risk factors, and this may partially account for the lower rates of angina and myocardial infarction in the black population116

retinopathy, the mean duration between diagnosis of diabetes and time of examination was 115 years; 373 of these individuals had severe retinopathy at the initial examination117 A higher frequency of hospital readmissions mainly for diabetic ketoacidosis in African-American patients was associated with socioeconomic factors, including being from a one-parent home and lacking third-party insurance118 Overall,
however, medical care for diabetes appears to be similar for blacks and whites with NIDDM Table 317119-121 Personal and lifestyle factors may also increase the risk of diabetic complications in African Americans In the NHANES II cohort there was an almost 50 greater frequency of cigarette smoking, a risk factor for cardiovascular disease and diabetic neuropathy,
Table 317

Medical Care for Black and White Adults with NIDDM, US, 1989
Black
One physician for regular care of diabetes 873 4 visits to regular physician per year 624 Mean no of visits to regular physician in past year 69 Insulin treated 519 Oral agent treated 501 Following a diet for diabetes 889 Self-monitors blood glucose 1/day Insulin-treated 140 Not insulin-treated 40 Seen a dietitian in past year 275 Patient education in managing diabetes 433 Mean no of health checks by a professional in past year Blood pressure 109 Blood glucose 45 Sores on feet 19 Visit to ophthalmologist in past year 436 Eye examination in past year 640 Dilated eye examination in past year 473 Visit to podiatrist in past year 191 Visit to cardiologist in past year 267
Source: References 119-121

RISK FACTORS FOR DIABETES
COMPLICATIONS

White
927 589 58 359 399 882 298 51 189 315 80 37 16 447 600 475 162 215

Many of the factors that influence the frequency of diabetic complications in African Americans and contribute to the excess morbidity seen in this ethnic group are amenable to intervention A list of some important factors is presented in Table 316 The type of diabetes may be an important determinant of the severity of diabetes complications in black Americans Among African Americans, the probability of developing ESRD is greater for individuals who have IDDM compared with those with NIDDM105 Individuals who have insulin-resistant diabetes have higher levels of cardiovascular disease risk factors, including LDLcholesterol and triglycerides116 Delay in diagnosis and treatment for diabetic complications may increase the likelihood of more severe morbidity and disability For 51 African Americans with diabetes who received an initial examination for
622

Figure 3110

Figure 3111

Frequency of Cigarette Smoking in Black and White Adults with NIDDM, US, 1989
50 40 30 20 10 0 White men Black men White women Black women

Prevalence of Hypertension in Black and White Adults with NIDDM, US,
1976-80
Diabetic whites US whites Diabetic blacks US blacks

100 80 60 40 20

18-39

6 0 40-59 Age Years

25-34

35-44 45-54 Age Years

55-64

65-74

Source: 1989 National Health Interview Survey Diabetes Supplement

Source: Reference 80

among newly diagnosed black versus white diabetic subjects 42 versus 287, respectively80 This differential was also found for males in the 1989 NHIS, where 34 of black men with diagnosed diabetes were current smokers compared with 20 of white men; rates for women with diagnosed diabetes were 15 and 17, respectively Figure 3110 Psychosocial factors including personal and family denial of the disease and limited education may lead to less compliance and poorer metabolic control of diabetes in African Americans122

DYSLIPIDEMIA
Figure 3112 shows the prevalence of dyslipidemia in blacks and whites with NIDDM in the 1976-80 NHANES II cohort127 For each lipid, the frequency of an abnormal value is lower in blacks than in whites Compared with nondiabetic blacks, diabetic blacks had a lower frequency of total cholesterol 240 mg/dl men, a lower frequency of low-density lipoprotein LDL cholesterol 160 mg/dl both sexes, a higher frequency of
high-density lipoprotein HDL cholesterol 35 mg/dl both sexes, and a higher frequency of fasting triglycerides 250 mg/dl women127

HYPERTENSION
Hypertension is a major risk factor for micro- and macrovascular disease in diabetes In the United States, hypertension occurs more frequently among black than white Americans with diabetes80 Figure 3111 About 60 of hypertension in diabetic blacks is controlled Table 318 Hypertension also occurs frequently among African-heritage populations with diabetes in the Caribbean123,124 The consistency of higher rates of hypertension among individuals of African decent in the Americas compared with other ethnic groups in the United States and Caribbean has led to the hypothesis that Western Hemisphere blacks are descendants of a highly selected group of Africans who were able to survive the long sea voyages from Africa by efficiently retaining salt, thereby maintaining blood volume homeostasis125 The high rates of hypertension among African Americans might be related to hyperinsulinemia and abnormal renal sodium transport126

Table 318

Hypertension in Persons with Diabetes Age 20-74 Years, US, 1976-80
Black
Hypertensive Diagnosed hypertension
Controlled Not controlled Using antihypertensive medications Undiagnosed hypertension Not hypertensive 703 637 399 238 319 66 297

White
632 537 321 216 331 96 368

Hypertension is defined as a medical history of physician-diagnosed hypertension and/or systolic blood pressure 160 mmHg and/or diastolic blood pressure 95 mmHg Source: Reference 80

623

Figure 3112

Dyslipidemia in Black and White Adults with NIDDM, US, 1976-80
60 50 40 30 20 10 0 Black men White men 60 50 40 30 20 10 0 Black women White women

Total Cholesterol LDL-Cholesterol HDL-Cholesterol 240 160 35

Triglycerides 250

Total Cholesterol LDL-Cholesterol HDL-Cholesterol 240 160 35

Triglycerides 250

Source: Reference 127

DIABETES MORTALITY IN AFRICAN AMERICANS

Unfortunately, there is no study of diabetes mortality in a population of African Americans To assess mortality from diabetes, death certificate data can be used, but there is substantial underreporting of diabetes on the death certificates of people known to have had diabetes For example, in a national sample of deaths in 1986, only 362 of blacks with diabetes and 386 of whites with diabetes had diabetes listed anywhere on their death certificates128
Data using diabetes as the underlying cause of death are even more problematic: Only 125 of blacks and 92 of whites with diabetes had diabetes listed as the underlying cause of death128 Despite this underreporting on death certificates and their serious inaccuracy, death certificates are frequently used to assess diabetes mortality Prior to World War II, diabetes was identified more frequently on death certificates as a cause of death among whites than among blacks in the United States75 However, since about 1950, diabetes mortality rates for African Americans have been consistently higher than for whites In 1993, diabetes was the ninth most frequently listed underlying cause of death in African-American males 3,620 deaths and the fourth most frequently listed underlying cause in African-American females 6,170 deaths129 The death rate per 100,000 population based on diabetes listed as the underlying cause of death was 237 for black males and 365 for black females Mortality rates based on death certificates in which diabetes was listed as either the underlying cause of
624

death or as a contributing cause are shown in Figure 3113113 Rates are based on the diabetic population,
estimated from the NHIS It appears that mortality rates may be higher for blacks at age 75 years and lower at age 75 years, but these data must be viewed with caution because of the documented substantial underreporting of diabetes on death certificates 128 and the differential reporting by black and white race128 Among other black populations in the Americas, mortality rates based on diabetes as the underlying cause listed on death certificates range from 8 per 100,000 to 63 per 100,000130-132 This wide range includes low
Figure 3113

Diabetes Mortality Based on Death Certificates Listing Diabetes as the Underlying or Contributing Cause of Death, US, 1989
25 2 15 1 05 0 White males Black males White females Black females

0-44

45-64

65-74 Age Years

7 5

Age-Adjusted

These data probably include only 36 of deaths of blacks with diabetes, based on the study in Reference 128 Source: Reference 113

rates that are similar to those of developing African countries and rates that are nearly twice as high as for African Americans in the United States Because diabetes death rates may depend on factors such as the physicians decision concerning what to assign as cause of death, the
prevalence of diabetes, access to medical care, and the adequacy of medical care, comparison of these rates is questionable The vast majority of the deaths attributed to diabetes relate to the more prevalent NIDDM subtype, and little is known of IDDM-specific diabetes mortality rates in African Americans In an evaluation of the 20-year mortality experience of IDDM cases in Allegheny County, PA, black subjects experienced a mortality rate nearly 25 times greater than whites 96 per 1,000 person-years versus 39 per 1,000 person-years, respectively133 Data from death certificates show a similar diabetes mortality rate for blacks and whites 01 per 100,000 population at age 15 years, where IDDM is the predominant form of diabetes113 Little is known of IDDM-specific mortality rates in black Caribbean populations, although it has been estimated that the diabetes mortality rate at age 0-14 years in Jamaica may be as much as 20 times that of African Americans in the United States134 Much of the IDDMassociated mortality in African Americans may be preventable133,134

tes in African Americans has more than tripled The recent focus on diabetes in African Americans has led to new insights
concerning the variability in clinical manifestations of the disease in black populations eg, insulin-resistant NIDDM and insulin-sensitive NIDDM, which have different cardiovascular disease risk profiles Such discoveries suggest the potential for improved diabetes treatment and care among African Americans However, new intervention strategies developed to reduce current levels of diabetes complications among African Americans must consider the socioeconomic and psychosocial factors that contribute to poor compliance to diabetes management strategies, in addition to smoking, diet, hypertension, and other risk factors for diabetes complications Data on the epidemiology and impact of diabetes in African Americans suggest several major needs, including: 1 identifying factors responsible for the increasing frequency of NIDDM in African Americans; 2 determining the etiology of the unusual types of diabetes in black populations; 3 addressing the high rates of morbidity and mortality associated with diabetes in blacks; 4 determining reasons for the high prevalence of diabetes-associated risk factors in blacks, particularly obesity and hypertension, and developing effective intervention
programs; and 5 increasing awareness in the black community of the problem of diabetes

CONCLUSION

Diabetes is of public health importance for all ethnic groups in the United States However, there is a need to address this problem specifically in the black population Over the past 30 years, the prevalence of diabe-

Dr Eugene S Tull is Assistant Professor, Diabetes Research Center, Department of Epidemiology, University of Pittsburgh School of Public Health, Pittsburgh, PA, and Dr Jeffrey M Roseman is Professor, Department of Epidemiology, University of Alabama School of Public Health, Birmingham, AL

625

REFERENCES
1 Department of Health and Human Services: Report of the Secretarys Task Force on Black and Minority Health, Volume 1: Executive Summary DHHS publ no 241-80-841/05306, 1989 2 World Health Organization: Diabetes Mellitus Report of a WHO Study Group Technical Report Series, no 727 Geneva, Switzerland, World Health Organization, 1985 3 Winter WE, Maclaren NK, Riley WJ, Clarke DW, Kappy S, Spillar RP: Maturity-onset diabetes of youth in black Americans N Engl J Med 316:285-91, 1987 4 Morrison EY: Diabetes mellitus–a third syndrome phasic insulin dependence International
Diabetes Federation Bulletin 26:6, 1981 5 Banerji MA, Lebovitz HE: Remission in non-insulin-dependent diabetes mellitus: Clinical characteristics of remission and relapse in black patients Medicine 69:176-85, 1990 6 Abu-Bakare A, Taylor R, Gill GV Alberti KGM: Tropical or , malnutrition-related diabetes: A real syndrome? Lancet 1:1135-38, 1986 7 National Diabetes Data Group: Classification and diagnosis of diabetes mellitus and other categories of glucose intolerance Diabetes 26:1039-57, 1979 8 World Health Organization: Report of the Expert Committee on Diabetes Mellitus Technical Report Series, no 646 Geneva, Switzerland, World Health Organization, 1980 9 Gorsuch AN, Spencer KM, Lister J, McNally JM, Dean BM, Bottozzo GF Cudworth AG: Evidence for a long pre-diabetic , period in type 1 insulin-dependent diabetes mellitus Lancet 2:1363-65, 1981 10 Trucco M, Dorman JS: Immunogenetics of insulin-dependent diabetes mellitus in humans Crit Rev Immunol 9:201-45, 1989 11 Permutt MA: Genetics of NIDDM Diabetes Care 13 Suppl 4: 1150-53, 1990 12 Ali Z, Alexis SD: Occurrence of diabetes mellitus after gestational diabetes mellitus in Trinidad Diabetes Care 13:527-29, 1990 13 Mclarty DG,
Pollitt C, Swai ABM: Diabetes in Africa Diabetic Medicine 9:670-84, 1991 14 Higman BW: Slave Populations of the British Caribbean: 18071834 Baltimore, MD, Johns Hopkins University Press, 1984, p 100-57 15 Engerman SL, Genovese ED: Race and Slavery in the Western Hemisphere Princeton, NJ, Princeton University Press, 1975, p 107-28 16 Klein HS: The Middle Passage Princeton, NJ, Princeton University Press, 1978, p 23-50 17 Reed ET: Caucasian genes in American Negroes Science 165:762-68, 1969 18 Hanis CL, Hewett-Emmett D, Bertin TK, Schull WJ: Origins of US Hispanics Diabetes Care 14:618-27, 1991 19 Valette I, Monplaisir N, Sorel G, Rigal C, Dijon V Raffoux C: , HLA A,B,C, and DR association with insulin-dependent diabetes in Martinique Tissue Antigens 32:1-5, 1988 20 Saha N, Samuel APW: A genetic study of blacks from Trinidad Hum Hered 37:365-70, 1987 21 Schultz HA, Schlesinger ER, Mosher WE: The Erie County survey of long term childhood illness: II Incidence and prevalence Am J Pub Health 58:491-98, 1978 Gorwitz K, Howen GG, Thompson T: Prevalence of diabetes in Michigan school-age children Diabetes 25:122-27, 1976 LaPorte RE, Tajima N, Dorman JS, Cruickshanks KJ, Eberhardt MS, Rabin
BS, Atchinson RW, Wagner DK, Becker DJ, Orchard TJ, Slemenda CW, Kuller LA, Drash AL: Differences between blacks and whites in the epidemiology of insulindependent diabetes mellitus in Allegheny County, Pennsylvania Am J Epidemiol 123:592-603, 1986 Wagenknecht LE, Roseman JM, Alexander WJ: Epidemiology of IDDM in black and white children in Jefferson County, Alabama, 1979-1985 Diabetes 38:629-33, 1989 Lorenzi M, Cogliero E, Schmidt NJ: Racial differences in incidence of juvenile-onset type 1 diabetes: Epidemiologic studies in southern California Diabetologia 28:734-38, 1985 Lipman TH: The epidemiology of type 1 diabetes in children 0-14 yr of age in Philadelphia Diabetes Care 16:922-28, 1993 Tull ES, Roseman JM, Christian CLE: Epidemiology of childhood insulin-dependent diabetes mellitus in the US Virgin Islands from 1979-1988: Evidence of an epidemic in the early 1980s and variation by degree of racial admixture Diabetes Care 14:558-64, 1991 Jordan OW, Lipton RB, Stupnicka E, Cruickshanks JK, Fraser HS: Incidence of Type 1 diabetes in people under 30 years of age in Barbados, West Indies: 1982-1991 Diabetes Care 17:428-31, 1994 MacDonald MJ: Lower frequency of diabetes among
hospitalized Negro than white children Theoretical implications Acta Genet Med Gamelol 24:119-26, 1975 Reitnauer PJ, Go RCP Acton RT, Murphy CC, Budowle B, , Barger BO, Roseman JM: Evidence of genetic admixture as a determinant in the occurrence of insulin-dependent diabetes mellitus Diabetes 31:532-37, 1982 Dunston GM, Henry LQ, Christian JO, Callender CO: HLADR3, DQ heterogeneity in American blacks is associated with susceptibility and resistance to insulin-dependent diabetes mellitus Transplantation Proceedings 21:653-55, 1989 Reitnauer PJ, Roseman JM, Barger BD, Murphy CC, Kirk A, Acton RF: HLA associations in a sample of the American black population Tissue Antigens 1:286-93, 1981 Tull ES, Makame MH, DERI Group: Evaluation of Type 1 diabetes in black African-heritage populations: No time for further neglect Diabetic Medicine 9:513-21, 1992 Chakraborty R, Mohammed KI, Nwankwo M, Ferrell RE: Caucasian genes in African-Americans Am J Human Genetics 50:145-55, 1992 Friedman JM, Failkow J: Genetics In Diabetes Mellitus and Obesity, Broduff BN, Bleicher SJ, eds Baltimore, MD, Williams and Wilkins, 1982, p 364-73 Dunston GM, Henry LW, Christian J, Ofosu MD, Callender CO: HLA-DR
heterogeneity in American blacks is associated with susceptibility and resistance to insulin-dependent diabetes mellitus Transplant Proc 21:653-55, 1992 Zeidler A, Loon J, Frasier D, Kumar D, Penny R, Teraski P: HLA-DRW antigens in Mexican-American and black-American diabetic patients Diabetes 29:247-50, 1980 Lee BW, Chan SH, Tan SH, Wee GB, Yap HK, Wong HB, Tan CL, Tan KW: HLA-system in Chinese children with insulin dependent diabetes mellitus: A strong association with DR3

22 23

26 27

626

Metabolism 33:1102-05, 1984 39 Platz P Jakobsen BK, Morling N, Ryder LP Svjgaard T, , , Christy M, Kromann H, Benn J, Nerup J, Green A, Hauge M: HLA-D and DR antigens in genetic analysis of insulin-dependent diabetes mellitus Diabetologia 21:108-15, 1981 40 Wang C, Rivas ML, Burghen GA, Hudson EC, Wyatt RJ: C4 and Bf phenotypes in black and Caucasian patients with childhood onset insulin-dependent diabetes mellitus J Clin Lab Immunol 30:183-90, 1989 41 Rodey GE, White N, Frazer TE, Dudquesnoy RJ, Santiago JV: HLA-DR specificities among black Americans with juvenileonset diabetes N Engl J Med 301:810-12, 1979 42 MacDonald MJ, Famuyiwa OO,
Nwabuelo IA, Bella AF Ju, naid TA, Marrari M, Duquesnoy RJ: HLA-DR associations in black type 1 diabetics in Nigeria: Further support for models of inheritance Diabetes 35:583-89, 1986 43 MacDonald MJ: Speculation on the evolution of insulin-dependent diabetes genes Metabolism 37:1182-84, 1988 44 Todd JA, Bell JI, McDevitt HO: HLA-DQ gene contributes to susceptibility and resistance to insulin-dependent diabetes mellitus Nature 329:599-604, 1987 45 Dorman JS, LaPorte RE, Stone RA, Trucco M: Worldwide differences in the incidence of type 1 diabetes are associated with the amino acid variation at position 57 of the HLA-DQ chain Proc Natl Acad Sci 87:7370-74, 1990 46 Reijonen H, Ilonen J, Knip M, Akerblom HK: HLA-DQ alleles and absence of Asp57 as susceptibility factors for IDDM in Finland Diabetes 40:1640-44, 1991 47 Serjeantson SW, Easteal S: Cross-ethnic group comparisons of HLA class II alleles and insulin dependent diabetes mellitus Baillieres Clin Endocrinol Metab 5:299-320, 1991 48 Todd JA, Mijovic C, Fletcher J, Jenkins D, Bradwell AR, Barnett AH: Identification of susceptibility loci for insulindependent diabetes by transracial gene mapping Nature 338:587-89, 1989 49 Mijovic
CH, Jenkins D, Jacobs KH, Penny MA, Fletcher JA, Barnett A: HLA-DQA1 and -DQB1 alleles associated with genetic susceptibility to IDDM in a black population Diabetes 40:748-53, 1991 50 Todd JA: Genetic control of autoimmunity in Type 1 diabetes Immunol Today 111:122-29, 1990 51 Neufeld M, MaClaren NK, Riley WJ, Lezotte D, McLaughlin JV Silvestein J, Rosenbloom AL: Islet cell and other organ , specific antibodies in US Caucasians and blacks with insulin-dependent diabetes mellitus Diabetes 29:589-93, 1980 52 Morrison ESY, Rosenbloom AL, MacLaren NK, Riley WJ, Kooperman S: Absence of islet cell antibodies in Jamaican blacks with diabetes mellitus West Indian Med J 35:35-37, 1986 53 Oli JM, Botazzo G, Doniach D: Autoimmunity of juvenile diabetes mellitus in Nigeria Ghana Med J 9:140-42, 1980 54 Christau B, Kroman H, Anderson O, Christy M, Buxchard K, Arnung K, Kristensen I, Petersen J, Steinrud J, Nerup J: Incidence, seasonal, and geographic patterns of juvenile onset insulin-dependent diabetes mellitus in Denmark Diabetologia 13:281-84, 1977 55 Colle E, Siemiatycki J, West R, Belmonte MM, Crepeau MP , Poirier R, Wilkins J: Incidence of juvenile onset diabetes in
Montreal–demonstration of ethnic differences and socioeconomic class differences J Chron Dis 34:611-16, 1984 56 LaPorte RE, Orchard TJ, Kuller LH, Wagner DK, Drash AL,

63 64

65 66 67

69 70

71 72

74 75

Schneider BB, Fishbein HA: The Pittsburgh Insulin-Dependent Diabetes Mellitus Registry The relationship of insulindependent diabetes mellitus incidence to social class Am J Epidemiol 114:379-84, 1981 Allen C, Palta M, DAlessio DJ: Incidence and differences in urban-rural seasonal variation of Type 1 insulin-dependent diabetes in Wisconsin Diabetologia 29:629-33, 1986 National Center for Health Statistics: Current estimates from the National Health Interview Survey, 1992 Vital and Health Statistics, Series 10, no 189, 1994 National Center for Health Statistics: Current estimates from the National Health Interview Survey, 1991 Vital and Health Statistics, Series 10, no 184, 1992 National Center for Health Statistics: Current estimates from the National Health Interview Survey, 1989 Vital and Health Statistics, Series 10, no 176, 1990 National Center for Health Statistics: Current estimates from the National Health Interview Survey, 1990 Vital and
Health Statistics, Series 10, no 181, 1991 Harris MI, Hadden WC, Knowler WC, Bennett PH: Prevalence of diabetes and impaired glucose tolerance and plasma glucose levels in US population aged 20-74 yr Diabetes 36:523-34, 1987 Tulloch JA, Johnson HM: A pilot survey of the incidence of diabetes in Jamaica W Ind Med J 7:134-36, 1958 Wright HB, Taylor B: The incidence of diabetes in a sample of the adult population in South Trinidad W Ind Med J 7:123, 1958 Tulloch JA: The prevalence of diabetes in Jamaica Diabetes 10:286-88, 1961 Poon-King T, Henry MV: Prevalence and natural history of diabetes in Trinidad Lancet i:155-59, 1962 Ashcroft MT, Beadnell HM, Bell R, Miller GJ: Characteristics relevant to cardiovascular disease among adults of African and Indian origin in Guyana WHO Bulletin 42:205, 1970 Florey CV McDonald HJ, Miall WE: The prevalence of dia, betes in a rural population of Jamaican adults Int J Epidemiol 1:157-66, 1972 Patrick AL, Boyd HA: Blood sugar levels, weights and heights of Tobagonians W Ind Med J 34:114, 1985 Beckles GLA, Kirkwood BR, Carson DC, Miller GJ, Alexis SD, Byam NTA: High total cholesterol and cardiovascular disease mortality in adults of Indian decent in
Trinidad, unexplained by major coronary risk factors Lancet i:129899, 1986 Omran AR: The epidemiologic transition theory: A preliminary update J Trop Pediat 29:305-16, 1983 Lipton RB, Liao Y, Cao G, Cooper RS, McGee D: Determinants of incident non-insulin-dependent diabetes mellitus among blacks and whites in a national sample: The NHANES I Epidemiologic Follow-up Study Am J Epidemiol 138:82639, 1993 Zimmet P Serjeantson S, Drowse G, Finch C, Collins V: , Diabetes mellitus and cardiovascular disease in developing populations: Hunter-gatherers in the fast lane In Sugars in Nutrition, Gracey L, Kretchmer N, Rosi P eds New York, NY, , Raven Press, 1991, p 197-209 Neel JV: Diabetes mellitus–a thrifty genotype rendered detrimental by progress? Am J Human Genetics 14:353-62, 1962 Roseman JM: Diabetes in black Americans In Diabetes in America, Harris MI, Hamman RF eds DHHS publ no NIH ,

627

85-1468, 1985, p VII 1-24 76 Stern MP Gaskill SP Hazuda HP Gardner LI, Haffner SM: , , , Does obesity explain excess prevalence of diabetes among Mexican-Americans? Results from San Antonio Heart Study Diabetologia 24:272-78, 1983 77 Lipscomb LG, Kato-Palmer S, Boggs WL, Moore D, Pope A: Black
Americans Diabetes Forecast 41:34-42, 1988 78 Brosseau JD: Native Americans Diabetes Forecast 41:42-48, 1988 79 Kuczmarski RJ, Flegal KM, Campbell SM, Johnson CL: Increasing prevalence of overweight among US adults JAMA 272:205-11, 1994 80 Harris MI: Noninsulin-dependent diabetes mellitus in black and white Americans Diabetes Metabolism Reviews 6:71-90, 1990 81 Hartz AJ, Rupley DC Jr, Kalkhoff R, Rimm AA: Relationship of obesity to diabetes: Influence of obesity and body fat distribution Prev Med 12:351-57, 1983 82 Kumanyika S: Obesity in black women Epidemiol Rev 9:3150, 1988 83 Cowie CC, Harris MI, Silverman RE, Johnson EW, Rust KF: Effect of multiple risk factors on differences between blacks and whites in the prevalence of non-insulin-dependent diabetes mellitus in the United States Am J Epidemiol 137:71932, 1993 84 OBrien TR, Flanders WD, Decoufle P Boyle CA, DeStefano , F Teutch S: Are racial differences in prevalence of diabetes in , adults explained by differences in obesity? JAMA 262:148588, 1989 85 Drury TF Powell AL: Prevalence of known diabetes among , black Americans In Diabetes in America, Harris MI, Hamman RF eds DHHS publ no NIH 87-1250, 1987 , 86 Zimmet PZ, Collins
VR, Dowse GK, Alberti KGGM, Toumilehto J, Gareeboo H, Chitson P: The relation of physical activity to cardiovascular disease risk factors in Mauritians Am J Epidemiol 134:862-75, 1991 87 Helmrich SP Ragland DR, Leung RW, Paffenbarger RS: Physi, cal activity and reduced occurrence of non-insulin-dependent diabetes mellitus N Engl J Med 325:147-52, 1991 88 Kriska AM, Bennett PH: An epidemiological perspective of the relationship between physical activity and NIDDM: From activity assessment to intervention Diabetes Metabolism Reviews 8:355-72, 1992 89 Sicree RA, Zimmet P King H, Coventry JS: Plasma insulin , response among Nauruans: Prediction of deterioration in glucose tolerance over 6 years Diabetes 36:179-86, 1984 90 Bogardus C, Lillioja S, Foley J, Christin L, Freymond D, Nyomba B, Bennett PH, Raven G, Salans L: Insulin resistance predicts the development of non-insulin dependent diabetes mellitus in Pima Indians Diabetes 36 Suppl 1:47A, 1987 91 Svec F Nastasi K, Hilton C, Bao W, Srinivasan SR, Berenson , GS: Black-white contrasts in insulin levels during pubertal development Diabetes 41:313-17, 1992 92 Harris MI: Impaired glucose tolerance in the US population Diabetes Care
12:464-74, 1989 93 Banerji MA, Lebovitz HE: Insulin-sensitive and insulin-resistant variants in NIDDM Diabetes 38:784-92, 1989 94 Banerji MA, Allen JN, Chaiken RL, Lebovitz HE: HLA-DQ associations distinguish insulin-resistant and insulin-sensitive variants of NIDDM in black Americans Diabetes Care 16:429-33, 1994

95 Winter WE, Riley WJ, McClaren NK: Maturity-onset diabetes in young black Americans N Engl J Med 317:380-82, 1987 96 Morrison EY, Ragoobirsingh D: J Type diabetes revisited J Natl Med Assn 84:603-08, 1992 97 Dooley SL, Metzger BE, Cho NH: Gestational diabetes mellitus: Influence of race on disease prevalence and perinatal outcome in a US population Diabetes 40 Suppl 2:25-29, 1991 98 National Center for Health Statistics: Advance report of maternal and infant health data from the birth certificate, 1991 Monthly Vital Statistics Report, Vol 42, no 11, Suppl, 1994 99 OSullivan JB, Mahan CM: Prospective study of 352 young patients with chemical diabetes New Eng J Med 278:103841, 1968 100 Roseman JM, Go RCP Perkins LL, Barger BD, Beel DA, , Goldenberg RL, DuBard MB, Huddelestone JF Sedaceck CM, , Acton RT: Gestational diabetes among African American women Diab Metab Reviews
7:93-104, 1991 101 Tull ES, Makame MH, Roseman JM: Diabetes mellitus in the African-American population In Handbook of Black American Health: The Mosiac of Conditions, Issues, Policies, and Prospects Livingston IL, ed Westport, CT, Greenwood Publishing Group Inc, 1994, p 94-109 102 Klein R, Klein BEK: Vision disorders in diabetes In Diabetes in America, Harris MI, Hamman RF eds DHHS publ no , NIH 85-1468, 1985, p XIII 1-36 103 Khan HA, Hiller R: Blindness caused by diabetic retinopathy Amer Ophthal 78:58-67, 1981 104 Harris MI, Rowland M, Klein R: Racial differences in the prevalence, severity, and treatment of retinopathy among adults with diabetes in the US population, 1995 105 Rabb MF Gagliano DA, Sweeney HE: Diabetic retinopathy in , blacks Diabetes Care 13 Suppl 4:1202-06, 1990 106 National Institute of Diabetes and Digestive and Kidney Diseases: US Renal Data System, 1994 Annual Data Report National Institutes of Health, 1994 107 Eggers PW, Connerton R, McMullen M: Health Care Financing Review 5:69-88, 1984 108 Cowie CC, Port FK, Wolfe RA, Savage PJ, Moll PP Haw, thorne VM: Disparities in incidence of diabetic end-stage renal disease according to race and type of diabetes N
Engl J Med 321:1074-79, 1989 109 Rostand SG, Kirk RA, Rutsky EA, Pate BA: Racial differences in the incidence of treatment for end-stage renal disease N Engl J Med 306:1276, 1982 110 Smith SR, Svetkey LP Dennis VW: Racial differences in the , incidence and progression of renal diseases Kidney International 40:815-22, 1991 111 Cowie CC, Port FK, Rust KF Harris MI: Differences in sur, vival between black and white patients with diabetic endstage renal disease Diabetes Care 17:681-87, 1994 112 West KM: Diabetes in American Indians and other native populations of the New World Diabetes 23:841-55, 1974 113 Centers for Disease Control: Diabetes Surveillance, 1993 Division of Diabetes Translation, CDC, 1993 114 Robertson WB, Strong JP: Atherosclerosis in persons with hypertension and diabetes mellitus Lab Invest 18:538-51, 1968 115 Shafer SQ, Bruun B, Richter RW: Brain infarction risk factors in black New York City stroke patients J Chron Dis 27:12733, 1990

628

116 Banerji MA, Lebovitz HE: Coronary heart disease risk factor profiles in black patients with non-insulin-dependent diabetes mellitus: Paradoxic patterns Am J Med 91:51-58, 1991 117 Appiah AP Ganthier R Jr, Watkins N: Delayed
diagnosis of , diabetic retinopathy in black and Hispanic patients with diabetes mellitus Ann Opthalmol 23:156-58, 1991 118 Glasgow AM, Weissberg-Benchell J, Tyann WD, Epstein SF , Driscoll C, Turek J, Beliveau E: Readmissions of children with diabetes to a childrens hospital Pediatrics 88:98-104, 1991 119 Cowie CC, Harris MI: Ambulatory medical care for diabetic blacks and whites in the US population Diabetes 43 Suppl 1:84A, 1994 120 Harris MI, Cowie CC, Howie LJ: Self-monitoring of blood glucose by adults with diabetes in the US population Diabetes Care 16:1116-23, 1993 121 Brechner RJ, Cowie CC, Howie LJ, Herman WH, Will J, Harris MI: Ophthalmic care for persons with diabetes mellitus in the US population JAMA 14:1714-18, 1993 122 Delamater AM, Albrecht DR, Postellon DC, Gutai JP: Racial differences in metabolic control of children and adolescents with type 1 diabetes mellitus Diabetes Care 14:20-25, 1991 123 Odugbesan O, Rowe B, Fletcher J, Walford S, Barnett AH: Diabetes in the UK West Indian community: The Wolverhampton survey Diabetic Medicine 6:48-52, 1988 124 Grell GAC: Hypertension in the West Indies Postgrad Med J 59:616-21, 1983 125 Grim CE: On slavery, salt and the
greater prevalence of hypertension in black Americans Clinical Research 36:426A, 1988 126 Douglas JG: Hypertension and diabetes in blacks Diabetes Care 13 Suppl 4:1191-95, 1990

127 Cowie CC, Howard BV Harris MI: Serum lipoproteins in , African Americans and whites with non-insulin-dependent diabetes in the US population Circulation 90:1185-93, 1994 128 Bild DE, Stevenson JM: Frequency of recording of diabetes on US death certificates: Analysis of the 1986 National Mortality Followback Survey J Clin Epidemiol 45:275-81, 1992 129 National Center for Health Statistics: Annual summary of births, marriages, divorces, and deaths: United States, 1993 Monthly Vital Statistics Report, Vol 42, no 13, October 11, 1994 130 World Health Organization: World Health Statistics Annual Geneva, Switzerland, World Health Organization, 1986, p 92-289 131 World Health Organization: World Health Statistics Annual Geneva, Switzerland,World Health Organization, 1987, p 92-181 132 World Health Organization: World Health Statistics Annual Geneva, Switzerland,World Health Organization, 1988, p 90-203 133 Tull ES, LaPorte RE, Vergona R, Gower I, Makame MH: A two-fold excess mortality among African-American
IDDM cases compared to whites: The Diabetes Epidemiology Research International experience Diabetes 41 Suppl 1:34A, 1992 134 Tull ES: Diabetes mellitus in the West Indies: Current aspects and future prospects IDF Bulletin 38:21-23, 1993 135 National Center for Health Statistics: Current estimates from the National Health Interview Survey, 1993 Vital and Health Statistics, Series 10, no 190, 1994

629

APPENDIX

Appendix 311

Number and Percent of Persons Who Have Diagnosed Diabetes, US, 1993
Black Age No years thousands
45 45-64 65-74
75

White No thousands
1,151 2,413 1,576 1,161 6,300

Percent
126 1125 1744 1411 411

Percent
082 563 954 1016 298

Total

304 578 292 141 1,315

Source: Reference 135

630

Source:diabetesvoice.org