Objective: To determine if the stroke risk factor profile of participants in a large, multicenter secondary stroke prevention trial changed over the recruitment period. Methods: The 3,680 participants in the Vitamin Intervention for Stroke Prevention (VISP) were categorized into four groups by enrollment date. Baseline patient characteristics and stroke risk factors were compared across groups. Results: Hypertension and hypercholesterolemia management improved but prevalence of three major stroke risk factors did not change. Patients enrolled later had better Mini-Mental State and lower NIH Stroke Scale scores, higher multivitamin use, lower prevalence of cortical infarctions, cardiac symptoms and prior stroke, and lower serum creatinine levels. Conclusions: Those participants enrolled in the later recruitment periods had a different risk factor profile and risk factors were managed differently compared to those enrolled earlier. Copyright © 2006 S. Karger AG.