Study finds diabetes is associated with worse outcomes for young stroke survivors

A new study led by researchers at Sunnybrook Research Institute, ICES and the University of Ottawa has found that diabetes is associated with poor long-term outcomes in young and midlife stroke survivors under 65 years of age.

The study, recently published in the Journal of the American Heart Association, builds upon earlier research demonstrating that diabetes is a risk factor for worse outcomes in older stroke patients. Although stroke incidence has declined overall in recent years, ischemic strokes among young people have increased. Ischemic strokes occur when blood flow to the brain is blocked, which can be caused by blood clots or plaque building up inside an artery wall.

“Even though outcomes for recovery in younger stroke patients are generally better, we know recovery can be variable. Few studies have explored risk factors associated with long-term outcomes in younger stroke survivors,” says Dr. Bradley MacIntosh, lead author of the study and senior scientist in the Hurvitz Brain Sciences Program at Sunnybrook Research Institute. “We were particularly interested in diabetes because we know it’s a risk factor for stroke and because it’s associated with poor long-term outcomes in older stroke survivors.”

Using data from the Ontario Stroke Registry, the researchers followed patients with or without diabetes who were admitted for acute ischemic stroke at an age of 65 years or younger. From 2003 to 2013, they found diabetes increased the likelihood of death while patients were still in hospital by 46 per cent and increased the need for discharge to long-term care by 65 per cent compared to those without the chronic condition. The authors note that although the mechanisms behind the association between diabetes and poor stroke outcomes aren't entirely clear, high blood sugar is associated with vascular changes and reduced benefits from clot-busting treatments which are typically given in a limited timeframe after onset of stroke to potentially improve the chance of recovery.

Dr. MacIntosh says the results showcase the need for more aggressive prevention and management strategies to address the poor outcomes associated with younger patients with pre-existing diabetes. “More research is needed to better understand if factors such as blood sugar control, diet, physical activity and medication compliance can lead to greater time living independently after stroke for young and midlife stroke survivors with diabetes,” says Dr. MacIntosh.

The researchers also emphasize the importance of collaboration between endocrinology and stroke neurology clinics to better understand the barriers to recovery for younger stroke survivors.

This study was supported by the Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, the Canadian Institutes of Health Research (CIHR), the Alzheimer’s Association (USA), Brain Canada and the Dr. Sandra Black Centre for Brain Resilience & Recovery.