CHD, Diabetes Linked to Worse Outcomes in Women With Ischemic Stroke

New research shows increased prestroke comorbidity, particularly diabetes and coronary heart disease (CHD), is independently associated with poorer poststroke functional status among women with ischemic stroke.

The prospective study showed prestroke diabetes and CHD were independently associated with poststroke disability in women at 90 days or more.

Study Investigator, Cheryl Bushnell, MD stated that, “It appears there is a slight influence of other comorbidities on poststroke disability, but the vast majority of it is explained by these 2 premorbid conditions [CHD and diabetes].”  It is well-known, said Dr. Bushnell, that women with ischemic stroke have poorer functional outcomes than their male counterparts, with higher rates of institutionalization and greater disability. However, she added, until now the reasons behind this phenomenon have not been investigated.

“We previously found the presence of prestroke CHD was independently associated with more severe strokes in women. This led us to hypothesize that prestroke heart disease might also be associated with worse poststroke functional outcomes. But we also wanted to look at the ‘big picture’ and examine whether other comorbidities might influence poststroke outcomes [in women].”

To identify specific outcome predictors, the researchers prospectively assessed baseline comorbid conditions in 133 consecutive women older than 18 years who presented within 24 hours of onset of acute ischemic stroke between September 2001 and February 2005.

The primary outcome was poststroke disability at 90 days or more evaluated with the modified Rankin Scale (mRS). The researchers also examined potential predictors of stroke severity, which was assessed using the National Institutes of Health Stroke Scale (NIHSS) 24 to 48 hours after admission and at 7 days or discharge, whichever came first.
Information on hypertension, hypercholesterolemia, prior stroke or transient ischemic attack, CHD, congestive heart failure, atrial fibrillation, peripheral vascular disease, and venous thrombosis were determined by medical records or self-report.

The modified Charlson Index was used to measure comorbidities and was hypothesized to be a predictor of outcome. This well-validated comorbidity index predicts 1-year mortality by weighting 16 conditions, including CHD and diabetes, and assigning a single score.

In multivariable modeling adjusted for initial NIHSS, independent predictors of disability were CHD and diabetes. It was only when diabetes and CHD were excluded that the Charlson Index became the sole predictor of poststroke disability, accounting for about 14% of the variance.

The study also revealed prestroke CHD was the only clinical factor associated with initial stroke severity.
According to Dr. Bushnell, the study results indicate a need for optimal management of women with diabetes and CHD, where evidence indicates there is room for improvement.

“We know, for example, that women are not well managed with respect to their lipids, both with respect to medication adherence and achieving target [serum cholesterol] levels,” she said.

She added that, based on these results, stroke outcome studies need to be adjusted for the presence of baseline comorbid conditions.

Presented Oct. 7, 2007, at the 132nd Annual Meeting of the American Neurological Association by researchers from Duke University Medical Center. in Durham, North Carolina.