Factors associated with cognitive improvement in subacute stroke survivors

Objective: To elucidate the characteristics of subacute stroke survivors with poststroke cognitive impairment, and examine the factors associated with cognitive improvement. Design: Retrospective cohort study. Participants: A total of 218 consecutive stroke survivors, who were admitted to a rehabilitation hospital between April 2014 and March 2015, were included. Methods: The prevalence of poststroke cognitive impairment, defined as having a Mini-Mental State Examination (MMSE) score <24 was investigated. Among those with poststroke cognitive impairment, the characteristics of patients with clinically significant improvement in MMSE scores (change ≥4) were explored. Univariable and multivariable regression analyses were performed to examine the relationship between Functional Independence Measure (FIM) items and improvement in post-stroke cognitive impairment. Results: Poststroke cognitive impairment occurred in 47.7% of participants. The mean improvement in their MMSE scores was 3.43. Participants who showed improvement had significantly higher FIM scores at discharge than those who did not show improvement. Regarding FIM items, eating (odds ratio 1.3; 95% confidence interval 1.0–1.7; p=0.041) and social interaction (odds ratio 1.5, 95% CI 1.1–2.1, p=0.010) were associated with cognitive improvement. Conclusion: Approximately half of subacute stroke survivors have poststroke cognitive impairment. Eating and social interaction are significantly associated with cognitive improvement.