Metformin treatment in elderly type II diabetic patients

Pharmacological treatment in elderly patients with type II, non-insulin dependent diabetes mellitus (NIDDM) is becoming a growing and complex problem in the clinical practice, since longevity in almost every population is increasing, and the prevalence of NIDDM also rises with age. It is generally indicated that age over 65-70 years represents a specific contraindication against the administration of the biguanides since the risk of the drug-associated lactic acidosis increases with age. However very few data exist in literature about the effect of biguanides, particularly metformin, in aging patients. Therefore, we aimed to evaluate the effects of adding metformin to poorly controlled sulfonylurea-treated elderly diabetic subjects for a one year period. Eighty-four type II diabetic patients aged more than 70 years and with a poor glycemic control were recruited after an informed consent. All diabetic patients were treated with various sulfonylureas at medium doses and presented renal and liver biochemical function tests within normal ranges and were free of severe macroangiopathy and respiratory or congestive heart failure. Metformin treatment was added to the previous sulfonylurea dosages in order to achieve a satisfactory glycemic control. All patients showed a marked improvement in the glycemic control with no significant modification in fasting blood lactate and a mild increase in the post-prandial lactate peak which, however, always felt largely within the normal ranges. Metformin also improved some metabolic vascular risk factors such as plasma cholesterol levels that were reduced, circulating HDL-cholesterol levels that mildly but significantly increased and uric acid that was lowered. In conclusion our data further support the opinion that metformin has not to be denied to diabetic patients on the sole basis of their age.