Lifestyle intervention in overweight individuals with a family history of diabetes.
OBJECTIVE
To assess the effect of lifestyle intervention over 2 years on changes in weight, coronary heart disease (CHD) risk factors, and incidence of diabetes in overweight individuals with a parental history of diabetes.


METHODS
Participants (n = 154), who were 30-100% over ideal body weight, had one or both parents with diabetes, and were currently nondiabetic, were randomly assigned to 2-year treatments focused on diet (decreasing calories and fat intake), exercise (goal of 1,500 kcal/week of moderate activity), or the combination of diet plus exercise or to a no-treatment control group. Subjects were reassessed at 6 months, 1 year, and 2 years.


RESULTS
At 6 months, the groups differed significantly on measures of eating, exercise, and fitness; weight losses in the diet and diet-plus-exercise groups were significantly greater than in the exercise and control conditions. Weight losses were associated with positive changes in CHD risk factors. After 6 months, there was gradual deterioration of behavioral and physiological changes, so that at 2 years, almost no between-group differences were maintained. Differences between groups in risk of developing diabetes were of borderline significance (P = 0.08). Strongest predictors were impaired glucose tolerance at baseline, which was positively related to risk of developing diabetes, and weight loss from baseline to 2 years, which was negatively related; in all treatment groups, a modest weight loss of 4.5 kg reduced the risk of type 2 diabetes by approximately 30% compared with no weight loss.


CONCLUSIONS
Although initially successful, the interventions studied here were not effective in producing long-term changes in behavior, weight, or physiological parameters. However, weight loss from 0 to 2 years reduced the risk of developing type 2 diabetes. Since modest weight loss significantly reduced risk of type 2 diabetes, further research is needed to determine how best to increase the percentage of subjects achieving at least a modest weight loss.
Wing
R R
RR
Department of Psychiatry, University of Pittsburgh School of Medicine, Pennsylvania 15213, USA.
Venditti
E
E
Jakicic
J M
JM
Polley
B A
BA
Lang
W
W
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D001835:Body Weight / Q000235:genetics / Q000502:physiology*; D003327:Coronary Disease / Q000097:blood / Q000503:physiopathology; D003627:Data Interpretation, Statistical; D003920:Diabetes Mellitus / Q000178:diet therapy / Q000235:genetics* / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology / Q000235:genetics / Q000503:physiopathology; D018752:Diet, Fat-Restricted; D015444:Exercise; D005192:Family Health; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000097:blood; D008019:Life Style; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D009765:Obesity; D012016:Reference Values; D013997:Time Factors; D015431:Weight Loss / Q000502:physiology
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007328:Insulin; D008055:Lipids