A Randomized Controlled Trial of Weight Reduction and Exercise for Diabetes Management in Older African-American Subjects

Abstract

OBJECTIVE To evaluate a weight loss and exercise program designed to improve diabetes management in older African-Americans. RESEARCH DESIGN AND METHODS Overweight African-Americans (n = 64) ages 55–79 years with NIDDM were randomized to either an intervention (12 weekly group sessions, 1 individual session, and 6 biweekly group sessions) or usual care (1 class and 2 informational mailings). Clinical and behavioral variables were assessed at 0, 3, and 6 months of treatment. RESULTS Significant net differences in the intervention versus usual care were observed for weight (−2.0 kg, P = 0.006), physical activity, and dietary intake of fat, saturated fat, cholesterol, and nutrition knowledge at 3 months (all P < 0.05) and for weight at 6 months (−2.4 kg; P = 0.006) and mean HbA_1c values at 3 and 6 months (respectively, −1.6 and −2.4%, both P < 0.01). After the adjustment for changes in weight and activity, the intervention participants were ∼ twice as likely to have a one unit decrease in HbA_1c value as those in usual care. Blood pressure increase sin usual care participants resulted in net differences (intervention minus control) at 3 and 6 months of −3.3 (P = 0.09) and −4.0 (P = 0.05) mmHg diastolic, respectively, and −8.4 (P = 0.06) and −5.9 (P > 0.10) mmHg systolic, respectively. Blood lipid profiles improved more in intervention than usual care participants, but not significantly. CONCLUSIONS The intervention program was effective in improving glycemic and blood pressure control. The decrease in HbA_1c values was generally independent of the relatively modest changes in dietary intake, weight, and activity and may reflect indirect program effects on other aspects of self-care.