A meta-analysis of mortality with intensive glucose lowering therapy

Several recent studies raised doubts as to the efficacy of intensive glucose control in diabetic patients. These French and Canadian researched performed a meta-analysis of randomized controlled trials looked at all cause and cardiovascular mortality with intensive glucose lowering treatment in type 2 diabetics. They searched Medline, Embase, and the Cochrane database of systematic reviews. The quality of clinical trials was measured using Jadad scores.

The researchers found: "13 studies were included. Of 34?533 patients, 18?315 received intensive glucose lowering treatment and 16?218 standard treatment. Intensive treatment did not significantly affect all cause mortality (risk ratio 1.04) or cardiovascular death (1.11). Intensive therapy was, however, associated with reductions in the risk of non-fatal myocardial infarction (0.85), and microalbuminuria (0.90) but a more than twofold increase in the risk of severe hypoglycaemia (2.33). Over a treatment period of five years, 117 to 150 patients would need to be treated to avoid one myocardial infarction and 32 to 142 patients to avoid one episode of microalbuminuria, whereas one severe episode of hypoglycaemia would occur for every 15 to 52 patients. In analysis restricted to high quality studies (Jadad score >3), intensive treatment was not associated with any significant risk of reductions but resulted in a 47% increase in risk of congestive heart failure."

The researchers concluded: "The overall results of this meta- analysis show limited benefits of intensive glucose lowering treatment on all cause mortality and deaths from cardiovascular causes. We cannot exclude a 9% reduction or a 19% increase in all cause mortality and a 14% reduction or a 43% increase in cardiovascular death. The benefit:risk ratio of intensive glucose lowering treatment in the prevention of macrovascular and microvascular events remains uncertain. The harm associated with severe hypoglycaemia might counterbalance the potential benefit of intensive glucose lowering treatment. More double blind randomised controlled trials are needed to establish the best therapeutic approach in people with type 2 diabetes."

Fuente: BMJ 2011; 343:d4169 doi: 10.1136/bmj.d4169 (Published 26 July 2011)     
http://www.bmj.com/content/343/bmj.d4169