Lead Investigator: Adam de Havenon, Yale University
Title of Proposal Research: Baseline Stroke Severity in Secondary Prevention Trials
Vivli Data Request: 8611
Funding Source: None
Potential Conflicts of Interest: None
Summary of the Proposed Research:
An ischemic stroke happens when a blockage cuts off the blood supply to part of your brain, killing brain cells. Damage to brain cells can affect how the body works. It can also change how you think and feel. Trials of medications to prevent a recurrent (second) ischemic stroke have historically not included participants who had disability from their first stroke. This may have influenced the results of these trials because a lot of stroke survivors have disability. The exception is the Prevention Regimen for Effectively Avoiding Second Strokes (PRoFESS) trial, which did include participants with disability. We are conducting an analysis of PRoFESS to better understand the possible benefits of including participants with disability in clinical trials, which could have a major impact on future trials and lead to more inclusive studies. We selected PRoFESS because it is a large cohort of patients with stroke and has a a large number of recurrent events during several years of follow-up. In the proposed project, we will report the number and rate of recurrent stroke in different categories of disability at the beginning of the trial. We will also examine if the level of baseline disability had an impact on how long participants stayed in the trial and if it influenced the effectiveness of the medications used in the trial. This study could have major public health impact by leading to more inclusive stroke prevention trials that include participants with disability at baseline.
Statistical Analysis Plan:
The primary study outcome is recurrent stroke. The secondary outcome is loss to follow-up. The tertiary outcomes include age, gender, race/ethnicity, and trial of ORG 10172 in acute stroke treatment (TOAST) classification of the qualifying stroke. We will report the outcomes after stratification by NIHSS (0-1, 2-3, 4-5, 6- 14, >14), consistent with original PRoFESS SAP stratification) and test for intergroup differences using the chi-square or FIsher’s exact tests depending on cell frequency. We may lump the top category into NIHSS ≥6 depending on cell counts. We will fit a time to event model to the primary outcome with the exposure of NIHSS categories, adjusted for covariates selected with least absolute shrinkage and selection operator (LASSO) methodology. Next we will fit a time to event model to the primary outcome with the interaction term of treatment arm (2×2) and NIHSS to understand if the trial results differed based on baseline NIHSS. Finally, as an exploratory analysis, we will repeat the analysis using the modified Rankin scale in place of the NIHSS, with the categories of 0, 1, 2, and 3-5. We will assume missing data is random and will not impute missing data in our analysis.
Requested Studies:
PRoFESS – Prevention Regimen For Effectively Avoiding Second Strokes: A Double-blind, Active and Placebo Controlled Study of Aggrenox vs. Clopidogrel, With and Without Micardis
Data Contributor: Boehringer Ingelheim
Study ID: NCT00153062
Sponsor ID: 9.159
Public Disclosures:
de Havenon, A., Viscoli, C., Kleindorfer, D., Sucharew, H., Delic, A., Becker, C., Robinson, D., Yaghi, S., Li, V., Lansberg, M.G. and Cramer, S.C., 2024. Disability and Recurrent Stroke Among Participants in Stroke Prevention Trials. JAMA Network Open, 7(7), pp.e2423677-e2423677. Doi : 10.1001/jamanetworkopen.2024.23677