Predictors of very early stroke recurrence in the POINT trial population

Abstract

Background Recent trials of acute secondary prevention in patients with minor ischemic stroke or transient ischemic attack (TIA) have demonstrated high rates of early recurrence within days of the initial event. Identifying clinical features associated with early recurrence may guide focused management. Methods Using logistic regression applied to the data of the Platelet Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial, we evaluated what baseline clinical factors predict outcome events occurring within 7 days of randomization. Results In the POINT trial, 181 subjects (3.7%) had early recurrence, defined as primary outcome events within 7 days of trial entry, whereas only 100 outcome events occurred over the remainder of the 90 day trial. Protective effects of dual antiplatelet therapy with clopidogrel plus aspirin were seen only as a reduction in these early recurrences, without any impact on later events. In univariate analysis, systolic blood pressure, diastolic blood pressure, serum glucose, initial carotid imaging results, study cohort (minor stroke or TIA), and treatment assignment were significantly associated with early recurrence. Multivariate logistic regression analysis identified a number of factors with significant independent associations with early recurrence, including carotid stenosis or occlusion (Odds Ratio [OR] 2.77; 95% confidence interval [CI] 1.78–4.31), cohort (minor stroke versus TIA) (OR 1.86; 95% CI 1.33–2.58), race (OR 1.57; 95% CI 1.10–2.25), baseline statin use (OR 0.68; 95% CI 0.49–0.95), systolic blood pressure (OR 1.10; 95% CI 1.03–1.18), serum glucose (OR 1.03; 95% CI 1.01–1.05), and age (OR 1.02; 95% CI 1.00–1.03). Receiver Operator Characteristic (ROC) analysis showed a 70% accuracy of the resulting logistic model in predicting early recurrence. Conclusions Early recurrence is high, and is concentrated in the first 7 days, in patients with minor stroke or TIA. A number of baseline clinical factors, including carotid disease, presentation with minor stroke rather than TIA, race, absence of statin usage, systolic blood pressure, and serum glucose, are independently associated with early event recurrence in the POINT trial population.

Statin Initiation and early stroke recurrence in the POINT Trial Population

“…As expected, based on known ischemic stroke preventive effects of statin treatment 12 , baseline statin treatment was found to be associated with reduced odds of both early ischemic stroke recurrence and recurrence over the extended 90-day period. The estimated protective effects of baseline statin were similar over the 7-day and 90-day periods, perhaps because most of the subjects on statin treatment at baseline continued to be treated with statin throughout their time in the trial.…”

“…153 subjects censored before 7 days (most on the day of randomization) were excluded from this logistic regression analysis. Previous multivariate logistic regression analysis, that had included these early censored subjects, and had imputed values of '0' for missing values of relevant variables, had shown significant associations (p<0.01) of recurrent ischemic stroke with presence of known carotid disease, patient cohort, treatment assignment to placebo, baseline systolic blood pressure, baseline serum glucose, age, prior statin use, and dichotomized race 12 . The present logistic regression analysis adjusted for these variables.…”