1. Introduction
cancer, n−3 fatty acid, time-to-first, CVD
CARDIOVASCULAR DISEASE, CVD, CANCER, EVENT, SECONDARY, EVENTS
This study aimed to investigate whether n−3 fatty acid supplementation reduced cardiovascular disease (CVD) events in a novel analysis using hierarchical composite CVD outcomes based on win ratio in the VITamin D and OmegA-3 TriaL (VITAL). This was a secondary analysis of our VITAL randomized trial, which assessed the effects of marine n−3 fatty acids (1 g/day) and vitamin D3 on incident CVD and cancer among healthy older adults (Effects of marine n−3 fatty acids’ (also called omega−3 polyunsaturated fatty acids) supplementation on cardiovascular disease (CVD) events have been inconsistent in meta-analyses summarizing randomized controlled trials (RCTs) [The inconclusive evidence for the effect of n−3 fatty acid supplementation on CVD events may be due to the fact that most trials modeled composite outcomes as time-to-first event (i.e., ignoring the clinical severity of individual components of composite outcomes) or generally did not account for baseline fish or n−3 intake [The problem of ignoring the differences in the clinical severity of individual components can be solved with a recently introduced statistical method named “win ratio” [