Global cognitive function before, surrounding, and after ischemic stroke: the role of risk and protective factors varies with time among ischemic stroke survivors

Abstract

An estimated 65% of individuals demonstrate multidomain cognitive impairment poststroke, although little is known about the varying role of cognitive risk and protective factors in preischemic, peri-ischemic, and postischemic stroke phases. Longitudinal changes in global cognitive function after ischemic stroke are not well characterized, especially in older adults over age 80. We examined global cognitive function trajectories in these three phases across a mean follow-up of 8.12 (2.30) years in 159 female stroke survivors aged 65–79 at baseline using linear mixed models with change points. In separate models controlling for demographic variables, we tested the interaction of baseline risk and protective factors with stroke phase on global cognitive function. None of the prestroke global cognitive function means or trajectories differed significantly. At the time of ischemic stroke, higher body mass index (BMI), the presence of hypertension (HTN), low optimism, and higher physical function were all associated with significantly greater mean decreases in global cognition (all p’s <.0.0001), but were not significantly different from the contrasting level (all p’s >0.05). Higher BMI, the presence of HTN, low optimism, and higher physical function were in turn protective of global cognitive decline postischemic stroke (all contrasting p values <.01). Baseline factors may play either a risk or a protective role in global cognitive function depending on the phase of ischemic stroke.

Keywords:

• aging
• stroke
• global cognitive function
• ischemic
• longitudinal

Additional information

Funding

WHIMS was funded by the National Heart, Lung and Blood Institute, Contract No. HHSN-268-2004-6-4221C through the initial follow-up period, WHIMS-ECHO is funded by the National Institute on Aging, Contract No. HHSN-271-2011-00004C, and the WHI program is funded by the National Heart, Lung and Blood Institute, U.S. Department of Health and Human Services.