Abstract P53: Long-Term Mortality Among Ischemic Stroke Patients With Pre-Existing Mild Cognitive Impairment or Dementia

Abstract

Introduction: The contribution of preexisting mild cognitive impairment (MCI) or dementia (MCID) towards long term mortality in Ischemic Stroke (IS) patients is under studied. Methods: We conducted a propensity score (PS) matched analysis of pooled data from 39 healthcare organizations to evaluate the association between MCID and post stroke mortality (PSM) through a 5-year period. Using ICD-10 codes for MCI, Alzheimer disease, vascular/other dementias, and MCID specific medications; we flagged preexisting MCID diagnoses up till 1 month prior to the index IS event (MCID group). The non-MCID group had no documented MCID diagnoses till after 1 month of the index event. Groups were PS matched on demographic (age, sex, race, ethnicity) and comorbidity variables. Risk Ratios (RR) and 95% confidence intervals (CI) were calculated. Results: Among 544,700 IS patients, 124,892 (22.9%) had preexisting MCID. MCID patients (vs. non-MCID) were older (mean age: 67.8 vs. 64.8 years), had higher proportion (%) of females (52.8 vs. 49.4) and Blacks (21.1 vs. 17.1). A higher proportion (%) of MCID patients had hypertension (77.3 vs. 36.0), diabetes (36.9 vs. 17.4), ischemic heart disease (31.6 vs 13.5), chronic kidney disease (21.4 vs. 7.8) and liver disease (9.5 vs. 3.1). Optimal co-variate balance was achieved post PS match (figure). In the unmatched sample, 8.6% of MCID and 6.0% of non-MCID patients experienced PSM by the 1-year time point; representing 56.2% and 64.2% of the total 5-year PSM, respectively. Matched and unmatched RR (CI) for PSM at 3 month and 1,3,5-year are reported (figure). An increasing risk of PSM was observed across the four time-points which was significantly higher for years 1,3, and 5 in the matched sample. Conclusion: A 24% long term increased risk of PSM was observed in a large national sample of IS patients with preexisting MCID. Majority of PSM burden is experienced by 1 year. MCID screening and exploring mechanisms of MCID-linked PSM is critical among IS patients.