Fish consumption and CHD mortality: an updated meta-analysis of seventeen cohort studies

Results of studies on fish consumption and CHD mortality are inconsistent. The present updated meta-analysis was conducted to investigate the up-to-date pooling effects.

A random-effects model was used to pool the risk estimates. Generalized least-squares regression and restricted cubic splines were used to assess the possible dose-response relationship. Subgroup analyses were conducted to examine the sources of heterogeneity.

PubMed and ISI Web of Science databases up to September 2010 were searched and secondary referencing qualified for inclusion in the study.

Seventeen cohorts with 315,812 participants and average follow-up period of 15·9 years were identified.

Compared with the lowest fish intake (<1 serving/month or 1-3 servings/month), the pooled relative risk (RR) of fish intake on CHD mortality was 0·84 (95% CI 0·75, 0·95) for low fish intake (1 serving/week), 0·79 (95% CI 0·67, 0·92) for moderate fish intake (2-4 servings/week) and 0·83 (95% CI 0·68, 1·01) for high fish intake (>5 servings/week). The dose-response analysis indicated that every 15 g/d increment of fish intake decreased the risk of CHD mortality by 6% (RR = 0·94; 95% CI 0·90, 0·98). The method of dietary assessment, gender and energy adjustment affected the results remarkably.

Our results indicate that either low (1 serving/week) or moderate fish consumption (2-4 servings/week) has a significantly beneficial effect on the prevention of CHD mortality. High fish consumption (>5 servings/week) possesses only a marginally protective effect on CHD mortality, possibly due to the limited studies included in this group.