Eighteen-Year Trends in Motor Recovery During Inpatient Rehabilitation After Ischemic Stroke.

Abstract

Background Trends in functional recovery after ischemic stroke within inpatient rehabilitation settings are not well-described. This study evaluated 18-year trends in functional motor improvement among adults receiving inpatient rehabilitation for ischemic stroke. Methods We conducted a retrospective cohort study of adults with ischemic stroke admitted to a large rehabilitation system from December 2001 to September 2019. The primary outcome was the attainment of a minimal clinically important difference (MCID) in the Functional Independence Measure Motor score, defined as a ≥20-point increase in Functional Independence Measure Motor score. Multivariable logistic regression was used to evaluate temporal trends and their interaction with insurance. Sensitivity analyses evaluated changes in case-mix index, Charlson Comorbidity Index, and length of stay. Results Among 9809 ischemic stroke rehabilitation admissions representing 9126 unique patients, 4445 (45.3%) admissions attained MCID. The adjusted odds of MCID attainment increased annually (odds ratio, 1.085 [95% CI, 1.067-1.104]). Model-based predicted probabilities for MCID attainment increased from 0.239 (95% CI, 0.192-0.286) in 2001 to 0.555 (95% CI, 0.509-0.601) in 2019 for Medicare Fee-for-Service and from 0.345 (95% CI, 0.307-0.383) to 0.564 (95% CI, 0.530-0.598) for non-Medicare patients. The year-by-insurance interaction was significant, indicating smaller annual gains for non-Medicare patients (odds ratio, 0.973 [95% CI, 0.953-0.993]; P =0.007). The case-mix index showed no temporal change, while the Charlson Comorbidity Index increased and length of stay declined over time. However, neither the Charlson Comorbidity Index, case-mix index, nor rehabilitation duration explains the temporal improvement in MCID attainment. Conclusions Functional motor recovery improved substantially over 18 years, independent of patient complexity and comorbidity burden, establishing contemporary benchmarks for inpatient stroke rehabilitation outcomes.