Relation of weight gain and weight loss on subsequent diabetes risk in overweight adults

Study objective-To determine whether long term weight gain and weight loss are associated with subsequent risk of type 2 diabetes in overweight, non-d iabetic adults. Design-Prospective cohort. Baseline overweight was defined as BMI greater t han or equal to 27.3 for women and BMI greater than or equal to 27.8 for me n. Annual weight change (kg/year) over 10 years was calculated using measur ed weight at subjects' baseline and first follow up examinations. In the 10 years after measurement of weight change, incident cases of diabetes were ascertained by self report, hospital discharge records, and death certifica tes. Setting-Community. Participants-1929 overweight, non-diabetic adults. Main results-Incident diabetes was ascertained in 251 subjects. Age adjuste d cumulative incidence increased from 9.6% for BMI<29 to 26.2% for BMI grea ter than or equal to 37. Annual weight change over 10 years was higher in s ubjects who become diabetic compared with those who did not for all BMI<35. Relative to overweight people with stable weight, each kg of weight gained annually over 10 years was associated with a 49% increase in risk of devel oping diabetes in the subsequent 10 years. Each kg of weight lost annually over 10 years was associated with a 33% lower risk of diabetes in the subse quent 10 years. Conclusions-Weight gain was associated with substantially increased risk of diabetes among overweight adults, and even modest weight loss was associat ed with significantly reduced diabetes risk. Minor weight reductions may ha ve major beneficial effects on subsequent diabetes risk in overweight adult s at high risk of developing diabetes.