Family history of type 2 diabetes predicts excess weight gain in type 1 diabetic patients on intensive therapy

Patients with type 2 diabetes mellitus gain weight when treated with insulin or oral sulfonylureas. A subset of type I diabetic subjects in the intensive therapy (IT) group of the Diabetes Control and Complications Trial (DCCT) gained excess weight following IT. In both types of diabetes, this weight gain was associated with increased central obesity, insulin resistance, and adverse lipoprotein changes. To determine if family history of type 2 diabetes predisposes an individual to weight gain in type 1 diabetes, we evaluated the effect of family history of type 2 diabetes in the DCCT IT subjects age ≥ 18 at baseline for whom complete lipid data was available (n = 582). After mean follow-up of 6.2 years, the subjects with a family history of type 2 diabetes (IT-type 2+) had gained more weight than those without such a history (change in BMI = 3.8 ± 2.8 vs. 2.9 ± 3.2 kg/m², respectively, p = 0.004) and had higher triglyceride (91.6 ± 56.5 vs. 76.3 ± 41.9 mg/dL, p = 0.024), higher LDL (118.5 ± 26.0 vs. 111.2 ± 27.2 mg/dL, p = 0.016), and higher apo B (89.5 ± 32.7 vs. 81.8 ± 19.0 mg/dL. p = 0.034). IT-type 24 subjects also required a greater insulin dose to maintain glycemic control at follow-up (0.726 ± 0.211 vs. 0.662 ± 0.206 u/kg per day, p = 0.0291. However, these changes were not accompanied by differences in HDL, LDL buoyancy, or waist-to-hip ratio. The only baseline variable significantly different between the two groups was plasma triglyceride (90.9 ± 45.2 vs. 77.9 ± 37.3 mg/dL, p = 0.009). We conclude that intensive therapy of type I diabetic subjects with a family history of type 2 diabetes may permit expression of a syndrome of central obesity, insulin resistance, and dyslipidemia similar to that found among type 2 diabetic patients.