Fish consumption and all‐cause mortality in a cohort of Swedish men and women

Abstract

Epidemiological studies of fish consumption and all-cause mortality have provided inconsistent results. We examined the dose-response association between fish consumption and mortality from all causes in a large population-based cohort of Swedish men and women. The study included 72 522 participants (33 973 women and 38 549 men), aged 45-83 years, from the Swedish Mammography Cohort and the Cohort of Swedish Men. Information on fish consumption was obtained through a self-administered questionnaire in 1997. Participants were followed for 17 years (1 January 1998 to 31 December 2014), and data on death and causes of death were ascertained through linkage to the Swedish Cause of Death Register. We used Cox proportional hazard regression to estimate hazard ratios (HRs) of death. Fish consumption was evaluated as a continuous predictor, flexibly modelled with restricted cubic splines to assess potential nonlinear associations. During follow-up, 16 730 deaths (7168 women and 9562 men) were recorded. The dose-response association between fish consumption and all-cause mortality was U-shaped. Compared with the median fish consumption (women: 25.0; men: 30.5 g day-1 ), lower levels of consumption were progressively associated with higher mortality risk up to 25% for women [HR 1.25; 95% confidence interval (CI): 1.11, 1.40] and 19% for men (HR 1.19; 95% CI: 1.07, 1.32) with no reported consumption. Increasingly higher levels of fish consumption were associated with higher mortality risk only amongst women, with a 39% higher mortality risk amongst women reporting the highest level of fish consumption (80 g day-1 ; HR 1.39; 95% CI: 1.15, 1.68). These results indicate a U-shaped association between fish consumption and all-cause mortality, particularly amongst women.