Aggressive control of blood sugar levels in type 1 and type 2 diabetes may reduce the risk for diabetic neuropathy

08-30-2012

Diabetic neuropathy affects nearly 10% of patients with diabetes at diagnosis, and 40% to 50% of patients after 10 years. Yet no systematic reviews have assessed the role of enhanced glucose control in preventing neuropathy.

In this current analysis, Dr. Callaghan and colleagues searched several databases for randomized controlled trials of enhanced glucose control in diabetes mellitus.

A meta-analysis of 2 studies (from the Diabetes Control and Complications Trial) that reported incidence of clinical neuropathy in 1228 participants with type 1 diabetes indicated a significantly reduced risk of developing clinical neuropathy in those patients with enhanced glucose control. Intensive control also resulted in favorable secondary outcomes in studies of both type 1 and type 2 diabetes.

Unfortunately, the incidence of hypoglycemic events and other serious adverse events, such as brain injury, was significantly higher with intensive glucose control in both types of diabetes.

The authors add that in type 2 diabetes mellitus, enhanced glucose control was associated with a reduced incidence of neuropathy, but the trend was not statistically significant (P = 0.06).

The authors note that the conclusions of the current review are heavily dependent on a limited number of trials. In type 1 diabetes, the Diabetes Control and Complications Trial accounted for 97.4% of the evidence, and in type 2 diabetes, the conclusions depended heavily on the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, published in 2010, which accounted for 70.6% of the evidence.

"In both types of diabetes there is a need for further research to discover the optimal target level which will reduce the development of neuropathy without increasing the risk of death, weight gain, hypoglycemia, and other adverse events," Dr. Callaghan and colleagues suggest.

The bottom line for all diabetic patients is that though we know that enhanced glucose control can prevent neuropathy, it is not known how strict that control should be. The take away is that the closer you monitor your blood glucose levels and keep them normal, the more likely it is that you will prevent neuropathy and all the complications arising from it.

 

* Brian C. Callaghan, MD, assistant professor from the Department of Neurology at the University of Michigan in Ann Arbor, and colleagues.

The researchers reported the results of their systematic review in the June issue of The Cochrane Library