Association between diastolic blood pressure and post-stroke cognitive impairment: a real-world retrospective cohort study.

BACKGROUND: Post-stroke cognitive impairment (PSCI) is a common complication after stroke, and blood pressure management is vital for stroke survivors. However, the association between diastolic blood pressure (DBP) during post-stroke rehabilitation and the risk of PSCI remains unclear. This study aims to evaluate this association in a real-world stroke cohort. METHODS: A total of 508 consecutive stroke patients admitted between May 2022 and March 2024 were included in this study. Univariate and multivariate logistic regression analyses were conducted to identify risk factors for PSCI. Restricted cubic spline (RCS) analysis was performed to explore the association between DBP and PSCI. Logistic regression models were used to evaluate the risk of PSCI in different DBP groups. Subgroup analysis was employed to assess the effect of DBP across different subgroups. RESULTS: During a median follow-up of 5.5 months, 41% of patients were identified as having PSCI. Univariate and multivariate logistic regression analyses indicated that low DBP is an independent risk factor for PSCI (odds ratio [OR] = 0.960 by 1 mmHg, 95% confidence interval [CI] = 0.933-0.988, p < 0.01). RCS analysis revealed a nonlinear relationship between DBP and PSCI incidence, with an inflection point of around 80 mmHg (P overall < 0.001, P nonlinear = 0.002). Logistic regression models suggested a higher risk of PSCI in the group with DBP < 75 mmHg compared with the group with 75-80 mmHg (OR = 2.606, 95% CI = 1.445-4.699, p < 0.01). CONCLUSION: DBP during post-stroke rehabilitation is associated with the incidence of PSCI in a non-linear manner. Specifically, a low DBP level during this period is an independent risk factor for PSCI. Maintaining a DBP above 80 mmHg during rehabilitation is beneficial for preventing PSCI.