Fish and Shellfish Consumption, Cognitive Health and Mortality from Alzheimer's Disease among US Adults Aged 60 and Older.

Background: Relationships of fish-shellfish consumption, cognitive health and mortality from Alzheimer's disease (AD) among US adults aged 60 years and older have not been adequately studied.

Objectives: To determine the relationship of fish-shellfish consumption, cognitive health and mortality from AD in US adults aged 60 years and older.

Design, Setting And Participants: The data of this cross-sectional study of US adults aged 60 years and older were from the National Nutrition and Health Examination Survey (NHANES) datasets. Frequency of fish-shellfish consumption, its association with subjective cognitive decline (SCD) and AD mortality of these participants between 1999 and 2018 and cognitive assessment scores between 2011 and 2014 were analyzed.

Measurements And Results: US adults aged 60 years and older consumed fish-shellfish 1.2 times/week and had a blood Hg of 1.63 ug/L on average between 1999 and 2018. Participants aged 60 years and older in the highest quartile of fish-shellfish consumption (~3 times/week) had significantly higher cognitive assessment scores than those in the lowest quartile (rare or no fish-shellfish consumption). Adults in the highest quartile of fish-shellfish consumption had a 30% lower risk (odds ratio 0.7, 95%CI 0.57-0.87) of SCD, and 44% lower risk (hazard ratio 0.56, 95%CI 0.35-0.9) of AD mortality than those in the lowest quartile.

Conclusion: Increased fish-shellfish consumption was associated with improved scores of cognitive assessment and reduced risks of SCD and AD mortality.