The effect of vitamin D and omega-3 fatty acid supplementation on pain prevalence and severity in older adults: a large-scale ancillary study of the VITamin D and OmegA-3 triaL (VITAL).

ABSTRACT

ABSTRACT A diet supplemented with vitamin D and marine omega-3 fatty acids may prevent and treat painful disorders by promoting the resolution of inflammation. However, large, randomized placebo-controlled trials evaluating the effects of supplementation with omega-3 fatty acids and vitamin D on the presence and severity of pain are lacking. VITamin D and OmegA-3 triaL-Pain (VITAL-Pain) is an ancillary study to the VITAL trial, a large randomized, double-blind, placebo-controlled trial of vitamin D (2000 IU/day) and omega-3 supplementation (1 g/day) over 5.3 years of median follow-up, among 25,871 older men and women. We assessed pain among those reaching the end of the VITAL intervention phase using questions from the 2012 National Health Interview Survey. We used ordinal logistic regression to test the effect of vitamin D and omega-3 fatty acids on the odds ratio (OR) and 95% confidence interval [CI] of reporting higher pain prevalence or severity. Overall, 19,611 participants provided complete pain information at the end of the VITAL trial. The ORs for higher pain prevalence or severity for vitamin D and omega-3 supplementation vs placebo were 0.99 ([CI] 0.94-1.05) and 0.99 ([CI] 0.94-1.04), respectively. There was no interaction between the 2 active treatments. Dietary supplementation with commonly used moderate doses of vitamin D or omega-3 fatty acids over a median of 5.3 years did not result in a lower prevalence or severity of pain in middle-aged and older U.S. adults.