Preventing type 2 diabetes mellitus.

Type 2 diabetes is a serious, costly, and increasingly common disease. Several conditions commonly seen in family medicine settings confer increased risk of developing diabetes. Among these conditions are impaired glucose tolerance, impaired fasting glucose, obesity, gestational diabetes, hypertension, hyperlipidemia, and menopause. We here present the results of a systematic review of the literature examining the evidence for different strategies aimed at preventing type 2 diabetes in patients with these conditions. The strongest evidence supports an intensive lifestyle intervention designed to induce modest weight loss. The greatest degree of prevention, based on lesser quality evidence, may be imparted by bariatric surgery. Metformin and troglitazone have appreciable evidence in specific populations, and orlistat and acarbose have slightly less evidence among obese patients, for preventing diabetes. Ramipril, captopril, losartan, pravastatin, and estrogens show some very preliminary promise for preventing diabetes in patients treated for hypertension, hyperlipidemia, and menopause, but each needs a more rigorous evaluation. Although more questions remain to be answered, family physicians now have tools available to help our patients lead lives free of diabetes.