Youth, Diabetes and Ischemic Stroke:A Deadly Combination?

Diabetes had a greater impact on risk of post-stroke death in younger patients than in older patients in recent research.

San Diego—With a conclusion that initially may seem counterintuitive, a study presented at the 2005 annual meeting of the American Neurological Association suggests that the risk of death from a first ischemic stroke is greater in younger patients than in older ones.

In fact, younger patients with diabetes and ischemic stroke were nearly twice as likely to die as patients without diabetes, according to the retrospective study led by Yong-Jin Cho, MD, assistant professor of neurology at Inje University Ilsan Paik Hospital, in South Korea.

"In general, older people have more comorbidities than younger people. If patients already have several diseases, such as hypertension, atrial fibrillation, myocardial infarction or hypercholesterolemia, than adding diabetes onto the list may not make a big difference in mortality," Dr. Cho said. "However, we can speculate that the impact of diabetes would be greater in patients who have fewer comorbidities—in other words, younger patients."

Dr. Cho and his team examined the records of all patients aged 18 years and older (n=1,543) who were hospitalized for a first ischemic stroke in the greater Cincinnati/Northern Kentucky region between July 1993 and June 1994. Subjects were followed for an average of eight years; 192 (12.4%) were excluded from the study because they died within 30 days of the stroke.

Of the 1,351 remaining patients, 442 (32.7%) had diabetes. The analysis showed that long-term mortality was increased for patients with diabetes in all age groups. The risk was greatest for the youngest age group (1.76; 18-64 years) compared with the middle age group, (1.58; 65-74 years) and the oldest age group (1.46; >75 years).

Rebecca Gottesman, MD, a stroke specialist and chief resident at Johns Hopkins Hospital in Baltimore, called the results "provocative," noting that severity and type of diabetes are keys to further understanding its contribution to mortality. "It may be that the younger patients were more likely to have more severe [type 1] diabetes, which could help explain why their mortality was higher."

The researchers are planning further study of their findings, including a comparison of the impact of diabetes on short- and long-term mortality after ischemic stroke.

—Andrew N. Wilner, MD, FAAN, FACP

Comment From the Field

The major risk factors for stroke are hypertension, dyslipidemia and poorly controlled diabetes. The younger patients may have had a significant difference in these risk factors to account for their increased susceptibility to mortality. What is more likely, however, is that older people have generalized ischemia that has been present for a long time and have developed collaterals sparing brain destruction. In addition, we need to differentiate ischemic from hemorrhagic stroke, the latter having graver consequences than the former.

Aaron Vinik, MD, PhD

Professor of Medicine, Pathology and Neurobiology, and Director of Research at the Strelitz Diabetes Institutes at Eastern Virginia Medical School in Norfolk