Influence of intensive diabetes treatment on body weight and composition of adults with type 1 diabetes in the diabetes control and complications trial

OBJECTIVE - To examine the differential effects of intensive and convention al diabetes therapy on weight gain and body composition in adults With type 1 diabetes. RESEARCH DESIGN AND METHODS - Between 1982 and 1989,1,246 adults (aged 18-3 9 years) in the Diabetes Control and Complications Trial were randomly assi gned to either conventional therapy (1-2 injections of insulin per day) or intensive therapy (multiple daily injections or continuous subcutaneous inf usion With frequent blood-glucose testing). Height and weight were measured at baseline and at annual Visits for an average of 6 years (range 3-9). Bo dy Composition was assessed cross-sectionally with bioelectrical impedance analysis during 1992, at which time waist and hip circumferences were measu red. RESULTS - Intensively treated patients gained an average of 4.75 kg more th an their conventionally treated counterparts (P < 0.0001). This represented excess increases in BMI of 1.5 kg/m(2) among men and 1.8 kg/m(2) among wom en. Growth-curve analysis showed that weight gain was most rapid during the first year of therapy. Intensive therapy patients were also more likely to become overweight (BMI greater than or equal to 27.8 kg/m(2) for men, grea ter than or equal to 27.3 kg/m(2) for women) or experience major weight gai n (BMI increased greater than or equal to5 kg/m(2)). Waist-to-hip ratios, h owever, did not differ between treatment groups, Major weight gain was asso ciated with higher percentages of body fat and greater fat-free mass, but a mong patients without major weight gain, those receiving intensive therapy had greater fat-free mass with no difference in adiposity. CONCLUSIONS - Intensive therapy for type I diabetes produces substantial ex cess weight gain compared with conventional therapy. However, the additiona l weight appears to include lean tissue as well as fat.