WEDNESDAY, Oct. 31 (HealthDay News) -- Intake of omega-3 fatty acids from fish, but not circulating biomarkers or supplements, correlates with modestly reduced cerebrovascular risk, according to a meta-analysis published online Oct. 30 in BMJ.
Rajiv Chowdhury, M.D., from the University of Cambridge in the United Kingdom, and colleagues reviewed the literature to identify prospective cohort studies and randomized controlled trials examining the associations of fish consumption and long-chain omega-3 fatty acids, omega-3 fatty acids biomarkers, or omega-3 fatty acids supplementations with cerebrovascular disease.
From 26 prospective cohort studies and 12 randomized controlled trials, including data on 794,000 non-overlapping people, the researchers identified 34,817 cerebrovascular outcomes. The pooled relative risk for cerebrovascular disease for two to four or five or more servings of fish a week versus one serving or less a week was 0.94 (95 percent confidence interval [CI], 0.90 to 0.98) and 0.88 (95 percent CI, 0.81 to 0.96), respectively. Comparing the top third of baseline long-chain omega-3 fatty acids with the bottom third for circulating biomarkers and for dietary exposures, the relative risk for cerebrovascular disease was 1.04 (95 percent CI, 0.90 to 1.20) and 0.90 (95 percent CI, 0.80 to 1.01), respectively. Compared with the control group, in primary and secondary prevention trials of long-chain omega-3 supplementation, the relative risk for cerebrovascular disease was 0.98 (95 percent CI, 0.89 to 1.08) and 1.17 (95 percent CI, 0.99 to 1.38), respectively.
"The beneficial effect of fish intake on cerebrovascular risk is likely to be mediated through the interplay of a wide range of nutrients abundant in fish," the authors write.