Abstract WP22: Cognitive Decline Among Older Adults With Stroke And Hospital-acquired Infections: The Cardiovascular Health Study

Introduction: Hospital-Acquired Infections (HAIs) are contracted during hospitalization for another disorder. We hypothesized that older adults with incident stroke and HAI experience faster subsequent cognitive decline than those having stroke without HAI and those without stroke. Methods: The Cardiovascular Health Study (CHS) is a cohort of Medicare-eligible participants aged ≥ 65 years. Incident ischemic stroke was ascertained from medical records. HAIs were assessed by hospital discharge ICD-9 codes. Global cognitive function was measured annually by modified mini-mental state examination (3MSE) and executive function by digit symbol substitution test (DSST). We used linear mixed models to estimate decline in mean 3MSE and DSST scores over a mean of seven years by incident stroke and HAI status among participants free of stroke at baseline. Results: In the 3MSE analysis, 393 participants had incident stroke and HAI, 766 had stroke only, and 4,284 had no stroke. With no stroke ( Fig 1A, black line), cognitive decline accelerated with age: mean declines of 0.27 points/year at age 70, 1.10 points/year at age 80, and 2.47 points/year at age 90. After stroke with HAI (red line), mean decline was 0.29 points/year faster than with no stroke (95% CI: 0.17, 0.40; p < 0.001). In contrast, after stroke without HAI (blue line), mean decline was similar to that with no stroke (0.09 points/year faster; 95% CI: -0.13, 0.32; p = 0.410). Mean decline was 0.19 points/year faster after stroke with HAI than after stroke without HAI, though these differences were not statistically significant (95% CI: -0.05, 0.44; p = 0.123). Mean decline in DSST score ( Fig 1B ) after stroke with HAI was similar to stroke without HAI (0.09 points/year faster decline after stroke with HAI; 95% CI: -0.08, 0.27; p = 0.297). Conclusions: Mean cognitive decline after stroke with HAI was faster than with no stroke but may be similar to that after stroke without HAI. As a limitation, we did not have data on stroke severity.