Long-term effectiveness of weight-loss interventions in adults with pre-diabetes - A review

Objective: To assess the effectiveness of weight-loss and weight-control interventions for adults with pre-diabetes (impaired fasting glucose and impaired glucose tolerance), an important risk factor for the development of type 2 diabetes. Methods: Computerized searches were conducted of multiple electronic bibliographic databases tip to August 2003. Randomized controlled trials in any language were selected that examined weight-loss or weight-control strategies rising at least one dietary, physical activity, or behavioral intervention, and with a follow-up interval of aparts per thousandY12 months. Effects were combined using a random effects model. Results: Studies were identified, with a total of 5168 participants. Follow-up ranged front 1 to 10 years. Quantitative synthesis was limited by the heterogeneity of populations, settings, and interventions, and by the small number of studies that examined outcomes other than weight. Overall, compared to usual care, font Studies with a follow-up of 1 year reduced weight by 2.8 kg (95% confidence interval [CI] 1.0-4.7) (3.3% of baseline body weight) and decreased body mass index by 1.4 kg/m(2) (CI=0.5-2.3). Weight loss at 2 bears was 2.7 kg (CI=1.9-3.4) (two studies). Modest improvements were noted in the few studies that examined glycemic control, blood pressure, and lipid concentrations (p>0.05). The incidence of diabetes was significantly lower in the intervention groups versus the controls in three of five studies examining this outcome at 3 to 6 years follow-up. Conclusions: Overall, weight-loss strategies rising dietary, physical activity, or behavioral interventions produced significant improvements in weight among persons with pre-diabetes, and a significant decrease in diabetes incidence. Further work is needed on the long-term effects of these interventions on morbidity and mortality and on how to implement these interventions in the community setting. (C) 2005 American Journal of Preventive Medicine.