Managing type 2 diabetes mellitus in patients with obesity.

Obesity is the most important modifiable risk factor for type 2 diabetes mellitus and most patients with diabetes are overweight or obese. It is well known that excess bodyweight induces or aggravates insulin resistance, which is a characteristic feature of type 2 diabetes. Thus, bodyweight plays a central role in the prevention and treatment of diabetes. Recent data suggest that lifestyle intervention in patients with impaired glucose tolerance results in an impressive reduction in the conversion to overt diabetes, which is greater than the effect of early intervention with drugs such as metformin or acarbose. The prevention of diabetes has been shown to be associated with the extent of weight loss. In patients with type 2 diabetes, weight loss by any means is followed by an improvement of metabolic control and associated risk factors. The most appropriate recommendation for obese patients with type 2 diabetes is a nutritionally balanced, moderately hypocaloric diet with a reduced intake of saturated fat and an increase in physical activity. If this standard approach is only partly successful or not at all, additional strategies such as weight-lowering drugs, very low-calorie diets for limited periods of up to 12 weeks, and, for severely obese patients, bariatric surgery should be carefully considered. A large body of data suggests that such measures can be very effective in this patient group by improving metabolic disturbances and blood pressure. However, it is extremely important for the long-term outcome that the treatment is tailored to the needs and wishes of the individual patient. There is growing agreement that due to the low success rate of conventional therapies and the overwhelming benefit from weight loss, more determined and aggressive strategies may be appropriate to achieve the central goal of weight reduction in obese patients with type 2 diabetes.