Association Between Dietary Fish and PUFA Intake in Midlife and Dementia in Later Life: The JPHC Saku Mental Health Study

J Alzheimers Dis. 2021;79(3):1091-1104. doi: 10.3233/JAD-191313.

Abstract

Background: The relationship between midlife dietary habits and risk of dementia remains unclear.

Objective: To investigate the association between dietary fish and n-3 polyunsaturated fatty acid (PUFA) consumption in midlife and risk of dementia in later life.

Methods: This population-based cohort study assessed food frequency (average intake in 1995 and 2000) and cognition (2014-2015) in 1,127 participants (aged 45-64 in 1995). We used logistic regression analyses to calculate odds ratios (ORs) for dementia and mild cognitive impairment (MCI) diagnoses for consumption quartiles of fish, PUFA-rich fish, total n-3 PUFAs, total n-6 PUFAs, types of PUFAs, and n-3/n-6 PUFA ratio. Estimated ORs were adjusted for age; sex; education; smoking status; alcohol consumption frequency; physical activity; histories of cancer, myocardial infarction, and diabetes mellitus; and depression.

Results: Significantly reduced risks of dementia over non-dementia (MCI plus cognitively normal) were observed in the second (OR = 0.43 (95% CI = 0.20-0.93)), third (OR = 0.22 (95% CI = 0.09-0.54)), and highest quartiles (OR = 0.39 (95% CI = 0.18-0.86)) for fish; the third (OR = 0.39 (95% CI = 0.16-0.92)) and highest quartiles (OR = 0.44 (95% CI = 0.19-0.98)) for eicosapentaenoic acid (EPA); the second (OR = 0.39 (95% CI = 0.18-0.84)), third (OR = 0.30 (95% CI = 0.13-0.70)), and highest quartiles (OR = 0.28 (95% CI = 0.12-0.66)) for docosahexaenoic acid (DHA); and the third (OR = 0.36 (95% CI = 0.16-0.85)) and highest quartiles (OR = 0.42 (95% CI = 0.19-0.95)) for docosapentaenoic acid (DPA).

Conclusion: High intake of fish in midlife might aid in preventing dementia.

Keywords: Cognitive dysfunction; dementia; diet; epidemiology; habits; longitudinal studies; observational study; risk factors; unsaturated fatty acids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Animals
  • Cognitive Dysfunction / epidemiology
  • Cognitive Dysfunction / prevention & control
  • Dementia / epidemiology
  • Dementia / prevention & control*
  • Diet Surveys
  • Fatty Acids, Omega-3 / administration & dosage*
  • Fatty Acids, Omega-6 / administration & dosage
  • Feeding Behavior*
  • Female
  • Fishes*
  • Humans
  • Japan / epidemiology
  • Logistic Models
  • Male
  • Middle Aged

Substances

  • Fatty Acids, Omega-3
  • Fatty Acids, Omega-6