Objective: To investigate the association between fish consumption and subclinical brain abnormalities.
Methods:In the population-based Cardiovascular Health Study, 3,660 participants age Ն65 underwent an MRI scan in 1992-1994. Five years later, 2,313 were scanned. Neuroradiologists assessed MRI scans in a standardized and blinded manner. Food frequency questionnaires were used to assess dietary intakes. Participants with known cerebrovascular disease were excluded from the analyses.
Results:After adjustment for multiple risk factors, the risk of having one or more prevalent subclinical infarcts was lower among those consuming tuna/other fish Ն3 times/week, compared to Ͻ1/month (relative risk 0.74, 95% CI ϭ 0.54 -1.01, p ϭ 0.06, p trend ϭ 0.03). Tuna/other fish consumption was also associated with trends toward lower incidence of subclinical infarcts. Additionally, tuna/other fish intake was associated with better white matter grade, but not with sulcal and ventricular grades, markers of brain atrophy. No significant associations were found between fried fish consumption and any subclinical brain abnormalities.
Conclusions:Among older adults, modest consumption of tuna/other fish, but not fried fish, was associated with lower prevalence of subclinical infarcts and white matter abnormalities on MRI examinations. Our results add to prior evidence that suggest that dietary intake of fish with higher eicosapentaenoic acid and docosahexaenoic acid content, and not fried fish intake, may have clinically important health benefits. Neurology ® 2008;71:439-446 GLOSSARY ARR ϭ absolute risk reduction; BMI ϭ body mass index; CHD ϭ coronary heart disease; CHS ϭ Cardiovascular Health Study; DHA ϭ docosahexaenoic acid; EPA ϭ eicosapentaenoic acid; FFQ ϭ food frequency questionnaire; HDL-C ϭ high-density lipoprotein cholesterol; LDL-C ϭ low-density lipoprotein cholesterol; PUFA ϭ polyunsaturated fatty acid; RR ϭ relative risk.Clinically unrecognized or "silent" brain infarcts are very common, particularly with advancing age. Among adults age Ն65 without infarcts on initial brain MRI, nearly 20% had at least one new infarct when MRI was performed about 5 years later, but without recognized TIA or clinical stroke in nearly 90% of cases.1 Persons with MRI-defined infarcts experience greater cognitive decline than persons without infarcts, and such individuals are also at higher risk of future clinical stroke.