Functional status at 30 and 90 days after mild ischaemic stroke

Abstract

Background/objective: This study compares the global disability status of patients who had a mild ischaemic stroke at 30 and 90 days poststroke, as measured by the modified Rankin Scale (mRS), and identifies predictors of change in disability status between 30 and 90 days.

Methods: The study population included 1339 patients who had a ischaemic stroke enrolled in the Mild and Rapidly Improving Stroke Study with National Institutes of Health (NIH) stroke score 0-5 and mRS measurements at 30 and 90 days. Outcomes were (1) Improvement defined as having mRS >1 at 30 days and mRS 0-1 at 90 days OR mRS >2 at 30 days and mRS 0-2 at 90 days and (2) Worsening defined as an increase of ≥2 points or a worsening from mRS of 1 at 30 days to 2 at 90 days. Demographic and clinical characteristics at hospital arrival were abstracted from medical records, and regression models were used to identify predictors of functional improvement and decline from 30 to 90 days post-stroke. Significant predictors were mutually adjusted in multivariable models that also included age and stroke severity.

Results: Fifty-seven per cent of study participants had no change in mRS value from 30 to 90 days. Overall, there was moderate agreement in mRS between the two time points (weighted kappa=0.59 (95% CI 0.56 to 0.62)). However, worsening on the mRS was observed in 7.54% of the study population from 30 to 90 days, and 17.33% improved. Participants of older age (per year OR 1.02, 95% CI 1.00 to 1.03), greater stroke severity (per NIH Stroke Scale (NIHSS) point at admission OR 1.17, 95% CI 1.03 to 1.34), and those with no alteplase treatment (OR 1.72, 95% CI 1.11 to 2.69) were more likely to show functional decline after mutual adjustment.

Discussion: A quarter of all mild ischaemic stroke participants exhibited functional changes between 30 and 90 days, suggesting that the 30-day outcome may insufficiently represent long-term recovery in mild stroke and longer follow-up may be clinically necessary.

Trial registration number: NCT02072681.

Keywords: Risk Factors; Stroke.

Conflict of interest statement

Competing interests: JGR: grant from Genentech to U Miami to support role as PI of MaRISS; personal fees from Genentech for role as a member of the steering committee for the PRISMS trial and member of the independent data monitoring committee of the TIMELESS Trial. HG: grant from Genentech to U Miami to support role as MaRISS Study Epidemiologist EE Smith: none I Campo-Bustillo: grant from Genentech to U Miami to support role as MaRISS Study Manager. YK: none S Tai: none N Riley: none. HMA: none. BMG: none. DG: none. NSS: none. KEO: none. CGB: none. AGK: none. SSB: none. ACK: none. RLS: grants from NIH grants (NINDS, NIMHD, NCATS), from the Florida Department of Health for the support of the Florida Stroke Registry, and fees from American Heart Association for work as Editor-in-Chief of Stroke. PK: funds to her institution from Genentech (PRISMS Trial National PI, HAMLET Steering Committee member), Diamedica (Scientific Advisory Board), Lumosa (Consultant and DSMB Representative), Nervive (NIH SBIR Co-Investigator) and Cerenovus (Investigator-Initiated ENDOLOW Trial MPI); fees from Bayer (PACIFIC-Stroke Trial National Leader). HMA: none. LHS: scientific consultant and steering committee member, TIMELESS Trial (Genentech); consultant (LifeImage); consultant on stroke systems of care, Massachusetts Department of Public Health; DSMB member, MIND Study (Penumbra) and PHAST-TSC Study (Diffusion Pharmaceutical); National PI, Stroke AF Study (Medtronic); National Co-PI, MR WITNESS Study (NINDS) (alteplase provided free of charge to Massachusetts General Hospital, supplemental per-patient payments sites by Genentech); Site PI, New England Regional Coordinating Center, StrokeNet (NINDS).

© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Change in modified Rankin Scale (mRS) between 30 and 90 days.

Figure 2

Distribution of modified Rankin Scale (mRS) at 30 and 90 days poststroke (%).