Introduction:
Low serum 25-hydroxyvitamin D (25(OH)D) and low marine omega-3 fatty acid (n-3) intake are associated with increased stroke risk in observational studies. Among stroke patients, low serum 25(OH)D at admission predicts poor outcomes and animal studies suggest that higher n-3 intake may diminish brain damage in ischemic stroke. However, few studies have examined effects of vitamin D or n-3 supplements on stroke outcomes.
Hypothesis:
We hypothesized that vitamin D (cholecalciferol, 2,000 IU/day) or n-3 (840 mg/day of EPA/DHA [ratio of 1.3:1]) supplementation initiated prior to stroke would reduce risk of functional limitations or physical disability after stroke compared to placebo.
Methods:
We used data from the completed VITamin D and OmegA-3 TriaL (VITAL) which randomized 25,871 men aged ≥50 years and women aged ≥55 years without cardiovascular disease or cancer at baseline and followed them for incident events over 5.3 years. Individuals experiencing a stroke were mailed a questionnaire to assess functional limitations (with the physical performance scale adapted from Nagi) and physical disability (with the modified Katz Activities of Daily Living and Rosow-Breslau Functional Health scales). We used logistic regression to analyze associations between randomized treatment assignments and limitations on each scale.
Results:
290 individuals experienced their first stroke during the trial (including 42 fatal strokes). 197 stroke survivors completed the stroke outcomes questionnaire a mean of 1.6 years after diagnosis. We observed no associations between randomized treatment to vitamin D and functional limitations (odds ratio (OR)=1.01, 95% confidence interval (CI): 0.52, 1.97) or physical disability on the Rosow-Breslau (OR=1.03, 95% CI: 0.31, 3.42) or Katz (OR=0.92, 95% CI: 0.50, 1.67) scales. Although not statistically significant, those randomized to n-3 had lower risk of functional limitations (OR=0.55, 95% CI: 0.28, 1.09) and physical disability on the Katz scale (OR=0.32, 95% CI: 0.50, 1.67) but not on the Rosow-Breslau scale (OR=1.03, 95% CI: 0.31, 3.42).
Conclusion:
Supplementation with vitamin D or omega-3 fatty acids prior to stroke did not result in significantly improved outcomes after stroke among older individuals.
Effect of vitamin D and/or omega‐3 fatty acid supplementation on stroke outcomes: A randomized trial
