Dietary Choline and Betaine Intake and 2-year Changes in Cognitive Function in Older Adults With Overweight or Obesity and Metabolic Syndrome: A Prospective Cohort Analysis

Dietary choline and betaine may protect against cognitive decline.

To examine longitudinal associations between dietary choline and betaine intake and 2-y cognitive changes in older adults.

This prospective cohort study is a secondary analysis nested within the PREDIMED-Plus trial. Participants included 6610 older adults aged 55-75 y with metabolic syndrome. Dietary choline and betaine intake were estimated at baseline, 1, and 2 y using a validated 143-item food frequency questionnaire. Cumulative averages were calculated. Cognitive function was assessed at baseline and 2 y using 5 composite scores based on 8 neuropsychological tests covering global cognition, general cognition, attention, executive function, and language. Multivariable-adjusted linear regression models evaluated associations between energy-adjusted cumulative average intakes and 2-y cognitive changes.

Over a median follow-up of 2 y (interquartile range: 1.95-2.05), each 1 mg/d higher energy-adjusted cumulative average dietary choline intake was associated with slower decline in attention [β = 5.20 × 10^-4; 95% confidence interval (CI): 1.61 × 10^-4, 8.79 × 10^-4; P = 0.005] and beneficial changes in language (β = 3.79 × 10^-4; 95% CI: 0.62 × 10^-4, 6.95 × 10^-4; P = 0.019). Participants in the highest choline tertile showed greater 2-y improvements in attention (β = 7.50 × 10^-2; 95% CI: 2.12 × 10^-2, 12.88 × 10^-2; P-trend = 0.006) and language (β = 5.82 × 10^-2; 95% CI: 1.04 × 10^-2, 10.59 × 10^-2; P-trend = 0.016) compared with the lowest tertile. Similarly, each 1 mg/d higher betaine intake was associated with more favorable changes in executive function (β = 7.48 × 10^-4; 95% CI: 1.71 × 10^-4, 13.20 × 10^-4; P = 0.011) and language (β = 9.13 × 10^-4; 95% CI: 2.96 × 10^-4, 15.31 × 10^-4; P = 0.004). Participants in the highest betaine tertile also exhibited greater 2-y improvements in language (β = 4.71 × 10^-2; 95% CI: 0.25 × 10^-2, 9.17 × 10^-2; P-trend = 0.036) compared with the lowest tertile.

Higher dietary choline and betaine intake were associated with modest short-term improvements in cognitive performance over 2 y in older adults. Longer-term studies are warranted. This trial was registered at www.isrctn.com as ISRCTN89898870.