Greater fish consumption tied to lower cerebrovascular disease risk

Eating more fish appeared linked to lower cerebrovascular disease risk, particularly among individuals younger than 75 years, according to results of a population-based study published in Neurology.

“Fish intake may favor brain vascular health through various endophenotypes or mechanisms, including ischemic events and small vessel disease,” Aline Thomas, MSc, of the University of Bordeaux in France, and colleagues wrote. “When investigating factors with a pleiotropic effect such as fish, there is interest to capture a global picture of the pathophysiological burden combining correlated biomarkers of underlying mechanisms into a continuous indicator, that may provide more power than studying each phenotype individually.”

The investigators aimed to examine the link between fish intake and global cerebrovascular burden according to brain MRI markers. In the current cross-sectional analysis, they included data of 1,623 participants (mean age, 72.3 years; 63% were women) from a population-based cohort who were aged 65 years or older and did not have dementia, stroke or history of hospitalized cardiovascular disease. Participants received a brain MRI with automated assessment of white matter hyperintensities, visual detection of covert infarcts and grading of dilated perivascular spaces. Thomas and colleagues used a frequency questionnaire to assess fish intake, with the first component of a factor analysis of mixed data applied to MRI markers serving as the primary outcome measure. Via linear regressions, they examined the association between fish intake and the cerebrovascular burden indicator.

Results showed an association between the first component of factor analysis and higher levels of all three MRI markers, as well as between greater fish intake and lower cerebrovascular disease burden. Participants who consumed fish two to three times per week and four or more times per week had beta scores of –0.19 and –0.3, respectively, as well as a lower indicator of cerebrovascular disease burden, compared with those who consumed fish less than once per week, in a model adjusted for total intracranial volume. Thomas and colleagues noted evidence of effect modification by age, with the association between fish and cerebrovascular disease burden stronger among participants aged 65 to 69 years and not significant among those aged 75 years or older. Among the younger age group, those who consumed fish two to three times per week exhibited a roughly equivalent but opposite direction effect of hypertension.

“If confirmed in prospective studies or clinical trials, the beneficial role of fish intake for the preservation of cerebrovascular health in very early brain aging stages may lead to relatively simple and inexpensive preventive strategies,” Thomas and colleagues wrote.