Associations of dietary choline intake with risk of incident dementia and with cognitive performance: the Kuopio Ischaemic Heart Disease Risk Factor Study

Moderate egg intake has been associated with better cognitive performance in observational studies. This association may be due to the rich content of choline, especially phosphatidylcholine, in eggs because choline has been suggested to have a role in the prevention of cognitive decline. We investigated the associations of dietary choline intake with the risk of incident dementia and with cognitive performance in middle-aged and older men in the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor Study. A population-based sample of 2497 dementia-free men aged 42–60 y was examined in 1984–1989. A subset of 482 men completed 5 different cognitive performance tests 4 y later. Dementia and Alzheimer disease diagnoses were retrieved from Finnish health registers. Dietary intakes were assessed with the use of 4-d food records at baseline. Cox regression and ANCOVA were used for the analyses. All analyses were also stratified by the apolipoprotein E phenotype (APOE-ε4 compared with other phenotypes). These data were available for 1259 men. The mean ± SD total choline intake was 431 ± 88 mg/d, of which 188 ± 63 mg/d was phosphatidylcholine. During a 21.9-y follow-up, 337 men were diagnosed with dementia. Those in the highest compared with the lowest phosphatidylcholine intake quartile had 28% (95% CI: 1%, 48%; P-trend = 0.02 across quartiles) lower multivariable-adjusted risk of incident dementia. Total choline intake had no association with the risk of incident dementia. However, both total choline and phosphatidylcholine intakes were associated with better performance in cognitive tests assessing frontal and temporal lobe functioning. For example, higher intakes were associated with better performance in verbal fluency and memory functions. The APOE phenotype had little or no impact on the associations. Higher phosphatidylcholine intake was associated with lower risk of incident dementia and better cognitive performance in men in eastern Finland. This trial was registered at clinicaltrials.gov as NCT03221127.