Lower Cognitive Function May Increase Stroke Risk
(HealthDay News) — Lower cognitive function is associated with increased risk of stroke in older adults, and cognitive decline increases after stroke vs. before stroke, according to a study published online August 7 in Stroke.
To examine the bidirectional association of incident stroke and cognitive decline, Kumar B. Rajan, PhD, from Rush University in Chicago, and colleagues interviewed 7,217 older adults from a biracial community without a history of stroke at three-year intervals. Standardized global cognitive scores were used to assess cognitive function, and stroke was ascertained by linkage with Medicare claims. The National Death Index was used to determine mortality during follow-up.
The researchers found that 16% of participants had incident stroke during follow-up. Lower baseline cognitive function correlated with a higher risk of incident stroke (hazard ratio, 1.61) after adjustment for known confounders. Before and after incident stroke occurrence, cognitive function declined by 0.064 U and 0.122 U per year, respectively, representing a nearly 1.9-fold increase after stroke. Mortality risk was increased in association with stroke (hazard ratio, 1.17) and cognitive decline (hazard ratio, 1.90).
"Cognitive decline increased mortality risk independent of the risk attributable to stroke and should be followed as a marker for both stroke and mortality," the authors write.