Introduction of insulin therapy and its effect on body weight in type 2 diabetes patients
Should one be afraid of insulin therapy in the obese patients?

Weight reduction is the foundation of non-pharmacological treatment of diabetes. However, it is also the most difficult part of diabetes therapy. A number of antidiabetic drugs, e.g. sulfonylureas or insulin, facilitate weight gain, which might be a serious obstacle on the track to optimal glucose control. Insulin initiation in type 2 diabetes is usually associated with 5 kg weight increase in the first year of treatment. This unfavourable effect of early insulin treatment in type 2 diabetes patients results in widespread unwillingness of physicians to introduce insulin, despite the presence of clear indications for this treatment. Since 2006 the European Association for the Study of Diabetes and the American Diabetes Association have recommended early insulin use in the natural course of type 2 diabetes, thus acknowledging the central role of beta cell dysfunction and deficit of insulin secretion in the pathophysiology of type 2 diabetes. The results of the studies conducted so far indicate that body weight increase following insulin therapy initiation is more likely to occur in younger patients and in those subjects in whom weight loss during the late period of oral antidiabetic treatment was more pronounced. In the elderly and more obese patients, however, body weight may actually decrease within the first year of insulin therapy. This observation should prevent physicians from withholding insulin treatment in this group of patients. Insulin therapy combined with metformin use is a well documented method of decreasing the risk of insulin treatment-associated weight gain. Concomitant use of metformin results in a decrease of insulin dose and leads to a reduction in calorie intake. Moreover, initiating insulin therapy with small doses and maintaining a slow rate of insulin dose increase may also significantly reduce the risk of insulin therapy related weight gain in type 2 diabetes patients.