quality indicators for diabetes (Singer et al., 1991, in Eddy, 1991; Diabetes is a heterogeneous, yet often serious, and common chronic …
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9
DIABETES MELLITUS
Steven Asch, MD, MPH
Several recent reviews provided the core references in developing quality indicators for diabetes Singer et al, 1991, in Eddy, 1991; Bergenstal, 1993; Gerich, 1989; Nathan, 1993, in Rubenstein and Federman, 1993; Garnick et al, 1994 Where these core references
cited studies to support individual indicators, we have included the original references We also performed narrow MEDLINE searches of the
medical literature from 1985 to 1995 to supplement these references for particular indicators Indicators of quality of care for gestational
diabetes are covered in Chapter 14 IMPORTANCE Diabetes is a heterogeneous, yet often serious, and common chronic condition prevalent throughout the world In 1992, the number of
diabetics in the United States alone was estimated to be 72 million The prevalence was estimated at 261 per 1,000 population, including all ages, while the prevalence in people under 44 was 68 Diabetes occurs
more frequently among women than men, and among nonwhites than whites American Diabetes Association [ADA], 1993 The complications of diabetes include visual loss and dysfunction of the heart, peripheral vasculature,
peripheral nerves, and kidneys Diabetes is the primary cause of blindness in the United States, and diabetics are at much higher risk of developing cataracts, glaucoma, and poor near vision The deleterious effect of diabetes on the
cardiovascular system contributes significantly to the risk of heart attacks, strokes, and, together with diabetic neuropathy, is the principal reason for amputations due to gangrene Garcia et al, 1974 About half of insulin-dependent diabetics develop kidney failure Bergenstal et al, 1993 All of these complications taken together
result in much higher death rates among diabetics than the remainder of the population Palumbo et al, 1976 Much of the benefit of high
quality care will accrue years later from the prevention of morbidity
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and mortality from such complications
Death rates from diabetes itself
increase with age ranging from 02 per 100,000 for those between 15 and 19 years of age to 146 per 100,000 for those between 50 and 54 years; older patients experience even higher rates National Center for Health Statistics [NCHS], 1994a The treatment of diabetes is resource intensive, with total costs estimated at 30-40 billion annually in
1992 ADA, 1993, or one of every seven dollars spent on health care in 1992 Rubin et al, 1994 Diabetes was the eighth most common reason for a patient visiting a physicians office in 1992 NCHS, 1994b EFFICACY AND/OR EFFECTIVENESS OF INTERVENTIONS Screening Indicators of the quality of screening diabetics for complications of diabetes are covered under diagnosis below This section covers Both the
screening patients not known to be diabetic for the disease
American College of Physicians ACP Singer et al, 1991, in Eddy, 1991 and the Canadian Task Force CTF on the Periodic Health Examination 1979 recommended that asymptomatic patients need not undergo screening for diabetes These recommendations were based on the
poor evidence that treatment of patients so identified would prevent complications Though many persons have asymptomatic hyperglycemia,
most complications of diabetes occur late in the course of the disease, limiting the benefits of early identification Since the publication of
those recommendations, the Diabetes Control and Complication Trial DCCT see below has added evidence for the efficacy of tight control in known diabetics in preventing complications DCCT, 1993a
However,
we have found no subsequent studies directly evaluating the efficacy of screening asymptomatic patients in reducing morbidity or mortality from diabetes Singer, 1988; CTF, 1979 Diagnosis The initial diagnosis of diabetes depends upon the measurement of a fasting blood sugar greater than 140/mg/dl or a postprandial blood sugar of greater than 200/mg/dl If a recorded blood sugar meets the above
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criteria, we recommend looking for notation of the diagnosis of diabetes in the progress notes or problem list Most experts also recommend a
complete history and physical examination, dietary evaluation, urinalysis for protein, measurement of blood creatinine, and a lipid panel at the time of initial diagnosis ADA, 1989 We do not propose
any of these as quality indicators for the initial diagnosis because of the small number of incident cases in our sample and the difficulty of defining the time of initial diagnosis We instead concentrate on the routine diagnostic tests that known diabetics should undergo regardless of their clinical status and stage of disease The first of these is the measurement of glycosylated A randomized controlled trial
hemoglobin to monitor
glycemic control
of 240 patients found that measuring hemoglobin A1c every three months led to changes in diabetic treatment and improvement in metabolic control, indicated by a lowering of average hemoglobin A1c values Larsen et al, 1990 The landmark DCCT followed 1,441 insulin-
dependent diabetics for 9 years and found that tight glycemic control and lower hemoglobin A1c values decreased rates of diabetic complications DCCT, 1993a Despite recommendations from a number of
specialty and generalist physician societies, there is great variation in the use of this test ADA, 1993; Bergenstal et al, 1993; Garnick et al, 1994; Goldstein et al, 1994 We propose as a quality indicator a
hemoglobin A1c test be done for all diabetics at six-month intervals, the longest recommended interval Home blood glucose monitoring has been shown to aid glycemic control in diabetics treated with insulin The DCCT employed home blood
glucose monitoring for its population of insulin-dependent diabetics, rather than the more easily tolerated urine glucose monitoring to achieve tight control, because moderate hyperglycemia 180 mg/dl may not cause glycosuria At least one small randomized trial n23
has
shown home blood glucose monitoring to improve glycemic control in obese insulin-dependent diabetics Allen et al, 1990 The optimal frequency
of monitoring has not yet been determined, though some studies have questioned patients ability to comply with frequent measurement Bergenstal et al, 1993; Health and Public Policy Committee, 1983;
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Muchmore et al, 1994; Gordon, 1991
Observational data have failed to
find any strong relationship between home blood glucose monitoring and glycemic control in noninsulin-dependent diabetics Patrick, 1994; Allen et al, 1990 Specialty societies recommend that patients on insulin
be offered training and equipment for home glucose monitoring, and we propose this as another indicator of diagnostic quality ADA, 1993 For patients not taking insulin, randomized trials have not shown home blood glucose to be any more effective at maintaining glycemic control than urine testing Allen et al, 1990 Because of the frequency of vision, cardiovascular, and renal complications among diabetics, many of which may be asymptomatic, the ADA 1989 has recommended several screening tests on an annual basis: eye exam, tests of triglycerides, total
cholesterol, HDL cholesterol, urinalysis, and total urinary protein excretion An annual eye and
vision exam conducted by an ophthalmologist, beginning five years after diagnosis, has also been recommended by the ACP, the ADA, and the American Academy of Ophthalmology AAO ACP, ADA and AAO, 1992 Retinal examination by generalists has been shown to be much less effective in detecting retinopathy at an early treatable stage Reenders et al, 1992 The routine evaluation of the other screening
recommendations has never been tested in controlled trials, but the conditions screened for hyperlipidemia, nephropathy, and ESRD are both more common in diabetics and amenable to intervention The Carter Center, 1985 Compliance with ADA screening recommendations has been
estimated to vary from 20 to 50 percent Garnick et al, 1994; Brechner et al, 1993 Other common treatable complications of diabetes include hypertension, cellulitis, and osteomyelitis The ADA recommends blood pressure measurement and examination of the feet at every visit to detect these complications early in their course as well as a careful history to elicit signs and symptoms of hypoglycemia and hyperglycemia No controlled
trials have examined the efficacy of a regular history and physical examination
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Treatment Recent debate in the area of diabetic treatment hinges on the utility of tight glycemic control The goal of tight control and
prevention of long-term complications through aggressive treatment is supported by the DCCT DCCT, 1993a The DCCT randomized 1,441 insulin-
dependent diabetics into conventional therapy or intensive therapy that included daily adjustments of insulin dosage, frequent home glucose monitoring, and nutritional advice Under the optimal circumstances
present in the DCCT trial, 44 percent of the intervention group achieved glycosolated hemoglobin values under the goal of 605 mg/dl percent at least once, but only 5 percent maintained average values in that range The intervention group developed 76 percent less retinopathy, 57 percent less albuminuria, and 60 percent less clinical neuropathy, but this reduction in diabetic complications may come at the expense of quality of life Nerenz et al, 1992 For example, the tight control group in
DCCT experienced a two- to three-fold increase in hypoglycemic episodes The efficiency of such methods in general practice has not
received adequate evaluation Nonetheless, the ADA recommends that all diabetics
over the age of seven be offered similar aggressive therapy Treatment strategies are different for Type I diabetes complete pancreatic deficiency of insulin and Type II diabetes abnormal secretion of insulin and resistance to insulin action In Type I
diabetes, emphasis is placed on avoidance of diabetic ketoacidosis and tight control of blood sugar levels through the judicious use of insulin In Type II diabetes, the focus shifts to control of symptoms,
usually with a combination of diet, exercise, and oral hypoglycemic agents If these measures fail to maintain adequate control in Type II We will review the
diabetics, then insulin therapy is warranted
evidence for quality indicators for each of these treatment modalities in turn Adherence to the ADA-recommended diet decreases insulin and oral hypoglycemic requirements and serum lipids Bantle, 1988 The DCCT
trial relied on dieticians and revealed that greater adherence to dietary instructions resulted in better control DCCT, 1993b Exercise
improves glucose tolerance and may reduce or eliminate the need for drug
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therapy Raz et al,
1994
The ADA and the American Board of Family
Practice recommend dietary and exercise counseling at both the initial diagnosis and before starting oral hypoglycemics or insulin ADA, 1989; Bergenstal et al, 1993 We recommend evaluating the medical record
for evidence that all diabetics have received dietary and exercise counseling and that Type II diabetics have undergone a trial of this conservative therapy prior to pharmaceutical intervention Randomized controlled trials have shown oral hypoglycemic agents to effectively improve glycemic control and prevent hyperglycemic coma Although the effectiveness of these agents in preventing longer-term complications of Type II diabetes has been questioned, particularly in the controversial UGDP Trial of the 1970s Gerich, 1989; Kilo et al, 1980; Knatterud, 1978, we recommend evaluating the medical record to determine if oral hypoglycemic therapy has been offered to symptomatic Type II diabetics who have already received a trial of dietary therapy Insulin treatment is essential for Type I diabetics and a treatment of last resort for Type II diabetics The literature contains varied recommendations as to the optimal timing and content of
insulin injections Gregerman, 1991, in Barker et al, 1991; Knatterud, 1978, and no single regimen has emerged as superior However, the ADA
recommends that all diabetics taking insulin receive formal instruction in the technique of injection ADA, 1989; Bergenstal et al, 1993 We
recommend evaluating the medical record for evidence that this has taken place We also recommend that symptomatic Type II diabetics who have
failed oral hypoglycemics be offered insulin Though quality indicators for treatment of hypertension are covered elsewhere Chapter 12, the intersection of diabetes and hypertension poses special treatment challenges Control of hypertension is perhaps In
the most crucial step in preventing diabetic nephropathy
particular, ACE inhibitors and possibly calcium channel blockers have been shown to reduce hyperalbuminuria and delay the progression to diabetic nephropathy Lederle, 1992; Anderson, 1990 Beta blockers on
the other hand may block the symptoms of hypoglycemia, and thus may be contraindicated in treated diabetics Hamilton, 1990 We propose that
diabetics with hypertension receive ACE inhibitors or calcium channel
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blockers as first-line pharmacotherapy
if diet has failed to control blood pressure Follow-up A study of internists and family practitioners using patient vignettes found wide variation in recommended follow-up intervals for diabetics Petitti and Grumbach, 1993 The ADA 1989 guidelines
recommend that regular visits be scheduled every three months for insulin-dependent diabetics and every six months for other diabetics As a minimum standard of care for patients with diabetes, we suggest a visit every six months
RECOMMENDED QUALITY INDICATORS FOR DIABETES MELLITUS
The following criteria apply to nonpregnant women age 18-50 Diagnosis Indicator 1 Patients with fasting blood sugar 140 or postprandial blood sugar 200 should have diabetes noted in progress notes or problem list Patients with the diagnosis of diabetes should have glycosylated hemoglobin every 6 months Quality of evidence III Literature ADA, 1989 Benefits Prevent diabetic complications Comments This definition of diabetes is accepted worldwide Blood sugar tests are often ordered as part of panels; this indicator will test the timeliness of follow-up on an abnormal result Randomized controlled trial of 240 patients indicated a significant decrease in hemoglobin
A1c among those whose hemoglobin A1c was monitored Time interval is that used in most clinical trials Eye and visual exam shown to detect retinopathy at an earlier treatable stage Other recommendations based on expert opinion, though studies have shown conditions they screen for to be more common in diabetics and all are susceptible to treatment with improved outcomes resulting from earlier detection These are ADA recommendations Earlier detection of treatable disease reduces probability of developing serious complications Exam provides an opportunity for patient education A small RCT found that home glucose monitoring increases glycemic control in insulin dependent diabetics Another study found no difference in control by frequency of monitoring Recommended by the ADA
2
I, III
ADA, 1989; Larsen et al, 1990; ACP, ADA and AAO, 1992 ADA, 1989; Larsen et al, 1990; ACP, ADA and AAO, 1992
Prevent diabetic complications
3
Patients with the diagnosis of diabetes should have each of the following at least once a year: a Eye and visual exam; b Triglycerides; c Total cholesterol; d HDL cholesterol; and e Urinalysis Patients with the diagnosis of diabetes should have each of the
following at every visit: f examination of feet; and g measurement of blood pressure Patients taking insulin should monitor their glucose at home
I, III
Prevent diabetic complications Prevent retinopathy, hyperlipidemia, atherosclorotic complications, and renal disease
4
I, III
ADA, 1989; Larsen et al, 1990; ACP, ADA and AAO, 1992 ADA, 1993
Prevent diabetic complications Prevent lower renal disease, extremity amputation, reduced morbidity from foot infections Prevent hypoglycemic episodes Prevent diabetic complications
5
III
132
Treatment Indicator 6 Diabetics should receive dietary and exercise counseling Quality of evidence II Literature Raz et al, 1994; Delahanty and Halford, 1993; ADA, 1989; Bergenstal et al, 1993 Benefits Reduce diabetic complications Comments Adherence to ADA diet decreases insulin and oral hypoglycemic requirements and serum lipids Exercise improves glucose tolerance and may reduce or eliminate need for drug therapy DCCT used dieticians and found that adherence to diet improved control and the ADA and the ABFP recommend their use No study has found that dietary counseling reduces diabetic complications Observational trials have shown oral
hypoglycemics to be effective in treating hyperglycemia and improving glycemic control No studies have shown reduction of diabetic complications Specialty societies and review articles widely recommend their use in mild to moderate disease before starting insulin Recommended by the ADA and ABFP
7
Type II diabetics who have failed dietary therapy should receive oral hypoglycemic therapy
III
ADA, 1989; Gerich, 1989; Bergenstal et al, 1993
Reduce diabetic complications
8
Type II diabetics who have failed oral hypoglycemics should be offered insulin If patient is receiving other antihypertensive therapy in the absence of ACE inhibitors or calcium channel blockers, progress note should document failure of ACE inhibitors and calcium channel blockers to control blood pressure
III
ADA, 1989; Bergenstal et al, 1993 Lederle, 1992; Anderson, 1990
Reduce diabetic complications
9
I
Reduce rate of renal failure
Randomized controlled trials have demonstrated a reduction in albuminuria and progression of diabetic nephropathy in hypertensive patients treated with ACE inhibitors and possibly calcium channel blockers
133
Follow-up Indicator 10 Patients with diabetes should have a
follow-up visit at least every 6 months Quality of evidence III Literature Bergenstal et al, 1993; ADA, 1989 Benefits Reduce probability of severe diabetic complications Comments Visits for diabetic patients in control should be every 3-6 months per ABFP Routine monitoring facilitates early detection and treatment of complications
Diabetic complications include visual loss and dysfunction of the heart, peripheral vasculature, peripheral nerves, and kidneys
Quality of Evidence Codes: I: II-1: II-2: II-3: III: RCT Nonrandomized controlled trials Cohort or case analysis Multiple time series Opinions or descriptive studies
134
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REFERENCES - DIABETES Allen BT, ER DeLong, and JR Feussner October 1990 Impact of glucose self-monitoring on non-insulin-treated patients with type II diabetes mellitus: Randomized controlled trial comparing blood and urine testing Diabetes Care 13 10: 1044-50 American College of Physicians, American Diabetes Association, and American Academy of Ophthalmology 15 April 1992 Screening guidelines for diabetic retinopathy Annals of Internal Medicine 116 8: 683-5 American Diabetes Association 1993 Direct and Indirect Costs of Diabetes in the United States
in 1992Alexandria, VA: American Diabetes Association American Diabetes Association May 1989 Standards of medical care for patients with diabetes mellitus Diabetes Care 12 5: 365-8 Anderson S 1990 Renal effects of converting enzyme inhibitors in hypertension and diabetes Journal of Cardiovascular Pharmacology 15 Suppl 3: S11-S15 Bantle JP 1988 The dietary treatment of diabetes mellitus Medical Clinics of North America 72 6: 1285-99 Bergenstal RM, WE Hall, and JA Haugen 1993 Diabetes Mellitus: Reference Guide, Fourth edLexington, KY: American Board of Family Practice Brechner RJ, CC Cowie, LJ Howie, et al 13 October 1993 Ophthalmic examination among adults with diagnosed diabetes mellitus Journal of the American Medical Association 270 14: 1714-7 Canadian Task Force on the Periodic Health Examination 3 November 1979 The periodic health examination Canadian Medical Association Journal 121: 1193-1254 The Carter Center July 1985 Closing the gap: The problem of diabetes mellitus in the United States Diabetes Care 8 4: 391-406 Delahanty LM, and BN Halford November 1993 The role of diet behaviors in achieving improved glycemic control in intensively treated patients in the Diabetes Control
and Complications Trial Diabetes Care 16 11: 1453-8 The Diabetes Control and Complications Trial Research Group 30 September 1993 The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-
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dependent diabetes mellitus New England Journal of Medicine 329 14: 977-86 The Diabetes Control and Complications Trial Research Group July 1993 Expanded role of the dietitian in the Diabetes Control and Complications Trial: Implications for clinical practice Journal of the American Dietetic Association 93 7: 758-67 Garcia MJ, PM McNamara, T Gordon, et al February 1974 Morbidity and mortality in diabetics in the Framingham population: Sixteen-year follow-up study Diabetes 23 2: 105-11 Garnick DW, J Fowles, AG Lawthers, et al 18 February 1994 Focus on quality: Profiling physicians practice patterns In Press, Journal Ambulatory Care Management Gerich JE 2 November 1989 Oral hypoglycemic agents New England Journal of Medicine 321 18: 1231-45 Golden MP, and DL Gray 1992 Diabetes Mellitus In Textbook of Adolescent Medicine McAnarney ER, RE Kriepe, DP Orr, et al,Philadelphia, PA: W B Saunders Company Goldstein DE, RR Little, H
Wiedmeyer, et al 1994 Is glycohemoglobin testing useful in diabetes mellitus? Lessons from the Diabetes Control and Complications Trial Clinical Chemistry 40 8: 1637-40 Gordon D, CG Semple, and KR Paterson 1991 Do different frequencies of self-monitoring of blood glucose influence control in type 1 diabetic patients Diabetic Medicine 8: 679-82 Gregerman RI 1991 Diabetes mellitus In Principles of Ambulatory Medicine, Third ed Editors Barker LR, JR Burton, and PD Zieve, 91351 Baltimore, MD: Williams and Wilkins Hamilton BP October 1990 Diabetes mellitus and hypertension American Journal of Kidney Diseases 16 4-Suppl1: 20-9 Health and Public Policy Committee, and American College of Physicians August 1983 Selected methods for the management of diabetes mellitus Annals of Internal Medicine 99 2: 272-4 Kilo C, JP Miller, and JR Williamson 1 February 1980 The Achilles heel of the University Group Diabetes Program Journal of the American Medical Association 243 5: 450-7 Knatterud GL, CR Klimt, ME Levin, et al 7 July 1978 Effects of hypoglycemic agents on vascular complications in patients with adult-onset diabetes Journal of the American Medical Association 240 1: 37-42
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Larsen
ML, M Horder, and EF Mogensen 11 October 1990 Effect of longterm monitoring of glycosylated hemoglobin levels in insulindependent diabetes mellitus New England Journal of Medicine 323 15: 1021-5 Lederle RM 1992 The effect of antihypertensive therapy on the course of renal failure Journal of Cardiovascular Pharmacology 20 Suppl 6: S69-S72 Muchmore DB, J Springer, and M Miller 1994 Self-monitoring of blood glucose in overweight type 2 diabetic patients Acta Diabetologica 31: 215-9 Nathan DM 1993 Diabetes mellitus In Scientific American Medicine Editor Rubenstein E, and D Federman,New York, NY: Scientific American Illustrated Library National Center for Health Statistics 18 August 1994 National Ambulatory Medical Care Survey: 1992 summary US Department of Health and Human Services, Hyattsville, MD National Center for Health Statistics 1994 Vital statistics of the United States, 1990, vol II: Mortality-part A US Department of Health and Human Services, Hyattsville, MD Nerenz DR, DP Repasky, FW Whitehouse, et al May 1992 Ongoing assessment of health status in patients with diabetes mellitus Medical Care Supplement 30 5, Supplement: MS112-MS123 Palumbo PJ, LR Elveback, C Chu, et al July
1976 Diabetes mellitus: Incidence, prevalence, survivorship, and causes of death in Rochester, Minnesota 1945-1970 Diabetes 25 7: 566-73 Patrick AW, GV Gill, IA MacFarlane, et al 1994 Home glucose monitoring in type 2 diabetes: Is it a waste of time? Diabetic Medicine 11: 62-5 Petitti DB, and K Grumbach September 1993 Variation in physicians recommendations about revisit interval for three common conditions Journal of Family Practice 37 3: 235-40 Raz I, E Hauser, and M Bursztyn 10 October 1994 Moderate exercise improves glucose metabolism in uncontrolled elderly patients with non-insulin-dependent diabetes mellitus Israel Journal of Medical Sciences 30 10: 766-70 Reenders K, E De Nobel, H Van Den Hoogen, et al 1992 Screening for diabetic retinopathy by general practitioners Scandinavian Journal of Primary Health Care 10: 306-9
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Rubin RJ, WM Altman, and DN Mendelson 1994 Health care expenditures for people with diabetes mellitus, 1992 Journal of Clinical Endocrinology and Metabolism 78 4: 809A-F Singer DE, JH Samet, CM Coley, et al 15 October 1988 Screening for diabetes mellitus Annals of Internal Medicine 109: 639-49 Singer DE, JH Samet, CM Coley, et al 1991 Screening for
diabetes mellitus In Common Screening Tests Editor Eddy DM, 154-78 Philadelphia, PA: American College of Physicians
Source:ssfcm.org
