Measures of Disease Control in Medicare Beneficiaries with Diabetes Mellitus

Objective: To investigate measures of disease control for Medicare beneficiaries with diabetes and their outpatient care in the fee-for-service setting.

Design: Retrospective cohort study.

Settings: Office practices in Alabama, Iowa, and Maryland of 293 primary care physicians (PCPs) who volunteered to participate in the Ambulatory Care Quality Improvement Project.

Participants: A total of 5980 patients with an average age of 75.2 years.

Measurements: For an 18-month period (1/1/94-6/30/95), medical records were abstracted for clinical parameters, including up to four blood glucose values; two blood pressure measurements; one total cholesterol value; two serum creatinine values; medication use, including antihypertensives, angiotensin-converting enzyme (ACE) inhibitors, and lipid-lowering agents; and frequency of glycosylated hemoglobin (GHb) determinations.

Results: During the study, 44% of patients received at least one GHb determination, 94% received at least one blood glucose, 68% at least one total serum cholesterol, 74% at least one serum creatinine test, and 97% at least one blood pressure measurement. Ten percent of patients had mean blood glucose levels > or = 250 mg/dL. Eighty-five percent had evidence of hypertension. Of this group of hypertensive patients with blood pressure readings available, 70% had blood pressure readings > or = 140/90 mm Hg, even though there were on medication that could have been prescribed for hypertension. Thirty-six percent of those who had evidence of hypertension were taking an ACE inhibitor. Thirty-two percent of those taking lipid-lowering medication had a total serum cholesterol value > or = 240 mg/dL. Statistically significant differences were noted for age and gender, with men and patients more than 85 years old generally having better measures of disease control.

Conclusions: Many older Medicare patients with diabetes did not achieve recommended target levels of blood glucose, blood pressure, and lipids. GHb and serum cholesterol are not being monitored at recommended intervals. Significant opportunities exist to improve diabetes care for this population.