Pre-stroke Disability and Long-Term Functional Limitations in Stroke Survivors: Findings From More of 12 Years of Follow-Up Across Three International Surveys of Aging

Abstract

Background: Almost 50% of the post-stroke disabled population already have a premorbid disability before stroke. These patients may be offered a different care pathway in the acute and subacute phase than those without pre-morbid disability. Therefore, the aim of this study was to assess the association of the severity of premorbid disability with change of limitations in basic and instrumental activities of daily living (ADL/IADL) 1 year after stroke and over the following decade.

Methods: Among 3,432 participants from HRS, SHARE and ELSA cohorts with a first stroke, ADL/IADL limitations were measured at 1-2 years prior to stroke, at 1 year post-stroke, and during the chronic phase. Modified Ranking Scale (P-mRS) was used to categorize the participants by level of premorbid disability (1-2 years pre-stroke). Change in ADL/IADL limitations by P-mRS level (0-1, 2-3, and 4-5) was assessed using a piecewise linear mixed model with a breakpoint set at 1 year post-stroke, stratified by median age groups.

Results: Increase in ADL limitations at 1 year post-stroke was less pronounced in P-mRS ≥2 (p < 0.005). After years of relative stability, limitations of ADL increased for all P-mRS levels (p = 0.003). In those aged ≥75 years at stroke event, the increase was similar irrespective of P-mRS (p = 0.090). There were no significant differences in IADL trajectories between P-mRS levels (p ≥ 0.127).

Conclusion: These results suggest similar trajectories of functional limitations between P-mRS levels up to 9 years post-stroke, highlighting the possible benefit of including patients with pre-morbid disability to certain treatments during the acute phase.

Keywords: chronic phase; functioning; limitation; premorbid disability; stroke.

Figure 1

Flowchart of the study samples.

Figure 2

Long-term trajectories of score of ADL limitations in stroke survivors by premorbid modified Rankin scale (P-mRS) stratified by age*. *Estimated from piecewise linear mixed model adjusted for socioeconomic variables, pre-stroke wave data collection, heath behaviors, BMI, and number of comorbidities. Breakpoint was set at 1 year post-stroke. Detailed changes in limitations between pre-stroke and 1 year post-stroke could not be modeled due to lack of information and was assumed linear for the sake of the analysis. ADL score range from 0 = no limitation to 7 = maximum limitation. Estimations are presented for a 16 year follow-up (corresponding to maximum follow-up with at least 5 participants by level of mRS) for population aged 50–74 years and a 11 year follow-up for those aged ≥75 years. Supplementary Table 4.

Figure 3

Long-term trajectories of score of IADL limitations in stroke survivors by premorbid modified Rankin scale (P-mRS) stratified by age*. *Estimated from piecewise linear mixed model adjusted for socioeconomic variables, pre-stroke wave data collection, heath behaviors, BMI, and number of comorbidities. Breakpoint was set at 1 year post-stroke. Detailed changes in limitations between pre-stroke and 1 year post-stroke could not be modeled due to lack of information and was assumed linear for the sake of the analysis. IADL score range from 0 = no limitation to 6 = maximum limitation. Estimations are presented for a 16 year follow-up (corresponding to maximum follow-up with at least 5 participants by level of mRS) for population aged 50–74 years and a 11 year follow-up for those aged ≥75 years. Supplementary Table 5.