Effects of hypoglycemic agents on mortality and major cardiovascular outcomes in patients with type 2 diabetes mellitus: a narrative review [88].

Type 2 diabetes mellitus acts as a risk factor for cardiovascular disease. It has been hypothesized that control of plasma glucose levels would reduce cardiovascular disease in type 2 diabetic patients--thus lowering parameters such as mortality rate, myocardial infarction or stroke. A narrative review was carried out looking at data on mortality and cardiovascular disease outcomes, including myocardial infarction and stroke, associated with hypoglycemic therapy in type 2 diabetic patients, starting with the University Group Diabetes Trial (1970-1978) and ending with the Veterans Affairs Diabetes Trial (2009). The data reviewed in the present text fail to confirm the hypothesis presented above. No consistent relation between lowering plasma glucose and favorable effects either on mortality rate or on major cardiovascular disease has been clearly shown to exist. However, there are interesting data concerning drugs that lower plasma insulin levels, particularly metformin, but also, to a certain degree, pioglitazone. Also of interest are data on a possible legacy effect observed in the long-term follow-up of patients previously under intensive plasma glucose control. Consistent evidence in favor of lowering glycated hemoglobin levels to values under 7% also seems to be lacking at present, at least concerning mortality and cardiovascular outcomes. For the time being, it can be argued that efforts should be centered on interventions with clear evidence of benefit, such as treatment of hypertension or excessive weight, as well as the use of statins.