Type 2 Diabetes a Greater Risk for Stroke than Previously Thought

KISSIMMEE, Fla?The risk that patients with newly diagnosed diabetes will have a stroke is double that of the general population, reported Canadian researchers at the American Stroke Association's Inter?national Stroke Conference 2006.

"One would think that the consequences of diabetes would occur over a long period, but we found that new-onset diabetics have double the rate of stroke in the first 5 years after diagnosis as the general population," said lead investigator Thomas Jeerakathil, MD, of the University of Alberta, Edmonton, Canada. "The finding suggests some of the cardiovascular effects of diabetes are already established at the time of diagnosis, and aggressive prevention is justified in this patient group."

In this new study, a database of ?residents of Saskatchewan, Canada, was used to identify 12,272 patients who received a new antidiabetes drug prescription between 1991 and 1996.

Of these, 9.14% had a stroke-related admission, and 21.9% of patients newly diagnosed with type 2 diabetes died during the 5-year follow-up.

The stroke rate was 642 per 100,000 person-years in patients with new diabetes compared with 315 per 100,000 person-years in the general population, corresponding to a 2.04 increased risk.

These findings suggest that patients with a new diagnosis of diabetes should have all cardiovascular risk factors managed optimally, Dr Jeerakathil said.

In another study, diabetes was identified as one of the most important risk ?factors for ischemic stroke; African Americans and persons <55 years old were at greatest risk, reported Brett Kissela, MD, of the University of Cincinnati in Ohio.

One third of the patients who suffered a total of 2432 strokes had a previous diagnosis of diabetes. Ischemic stroke patients with diabetes were younger than those without diabetes (70 vs 73 years) and were more likely to be African American (25% vs 15%) and to have a history of hypertension, hyperlipidemia, and myocardial infarction.

Among African Americans, those with diabetes had a 7- to 9-fold increased risk for stroke before age 45 compared with those without diabetes. Among whites, the risk of stroke before age 55 in those with diabetes was 6- to 17-fold higher compared with those without ?diabetes.

"If you look across the age spectrum, diabetes increases the risk for stroke by about 3-fold," said Dr Kissela. "But our study suggests that a lot of that risk is front-loaded. It's a bigger risk for younger than older people and probably higher for blacks than for whites."

Dr Kissela believes that diabetes should now be considered second only to hypertension as a risk factor for ischemic stroke.