Association of dietary cholesterol and egg intakes with the risk of incident dementia or Alzheimer disease: the Kuopio Ischaemic Heart Disease Risk Factor Study.

BACKGROUND: There is little information about the associations of intakes of cholesterol and eggs, a major source of dietary cholesterol, with the risk of cognitive decline in general populations or in carriers of apolipoprotein E ɛ4 (APO-E4), a major risk factor for dementia. OBJECTIVE: We investigated the associations of cholesterol and egg intakes with incident dementia, Alzheimer disease (AD), and cognitive performance in middle-aged and older men from Eastern Finland. DESIGN: A total of 2497 dementia-free men, aged 42-60 y in 1984-1989 at the baseline examinations of the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor Study, were included in the study. Information on the apolipoprotein E (Apo-E) phenotype was available for 1259 men. Data on cognitive performance tests at the 4-y re-examinations were available for 480 men. Dietary intakes were assessed with the use of 4-d food records at baseline. Dementia and AD diagnoses were based on Finnish health registers. Cox regression and ANCOVA were used for the analyses. RESULTS: During the 21.9-y follow-up, 337 men were diagnosed with dementia, and 266 men were diagnosed with AD. Neither cholesterol nor egg intake was associated with a higher risk of incident dementia or AD. For example, when evaluated continuously, each intake of 100 mg cholesterol/d was associated with a multivariable-adjusted HR of 0.90 (95% CI: 0.79, 1.02) for incident dementia, and each additional 0.5 egg (27 g)/d was associated with an HR of 0.89 (95% CI: 0.78, 1.01). However, egg intake was associated with better performance on neuropsychological tests of the frontal lobe and executive functioning, the Trail Making Test, and the Verbal Fluency Test. The Apo-E4 phenotype did not modify the associations of cholesterol or egg intake (P-interactions > 0.11). CONCLUSIONS: Neither cholesterol nor egg intake is associated with an increased risk of incident dementia or AD in Eastern Finnish men. Instead, moderate egg intake may have a beneficial association with certain areas of cognitive performance.

Associations of egg and cholesterol intakes with carotid intima-media thickness and risk of incident coronary artery disease according to apolipoprotein E phenotype in men: the Kuopio Ischaemic Heart Disease Risk Factor Study.

BACKGROUND: In general populations, the effects of dietary cholesterol on blood cholesterol concentrations are modest. However, the relation is stronger in those with an ɛ4 allele in the apolipoprotein E gene (APOE). There is little information on the association between cholesterol intake and the risk of coronary artery disease (CAD) among those with the ApoE4 phenotype. OBJECTIVE: We investigated the associations of intakes of cholesterol and eggs, a major source of dietary cholesterol, with carotid intima-media thickness and the risk of incident CAD in middle-aged and older men from eastern Finland. DESIGN: The study included 1032 men aged 42-60 y in 1984-1989 at the baseline examinations of the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor Study. Data on common carotid artery intima-media thickness (CCA-IMT) were available for 846 men. Dietary intakes were assessed with 4-d food records. Associations with incident CAD and baseline CCA-IMT were analyzed by using Cox regression and ANCOVA, respectively. RESULTS: The ApoE4 phenotype was found in 32.5% of the men. During the average follow-up of 20.8 y, 230 CAD events occurred. Egg or cholesterol intakes were not associated with the risk of CAD. Each 1 additional egg (55 g)/d was associated with a multivariable-adjusted HR of 1.17 (95% CI: 0.85, 1.61) in the ApoE4 noncarriers and an HR of 0.93 (95% CI: 0.50, 1.72) in the ApoE4 carriers (P-interaction = 0.34). Each 100-mg/d higher cholesterol intake was associated with an HR of 1.04 (95% CI: 0.89, 1.22) in the ApoE4 noncarriers and an HR of 0.95 (95% CI: 0.73, 1.25) in the ApoE4 carriers (P-interaction = 0.81). Egg or cholesterol intakes were also not associated with increased CCA-IMT. CONCLUSION: Egg or cholesterol intakes were not associated with increased CAD risk, even in ApoE4 carriers (i.e., in highly susceptible individuals).

Egg consumption and risk of incident type 2 diabetes in men: the Kuopio Ischaemic Heart Disease Risk Factor Study.

BACKGROUND: The prevalence of type 2 diabetes (T2D) is increasing around the world. Eggs are a major source of cholesterol, which has been associated with elevated blood glucose and an increased risk of T2D. However, there are limited and conflicting data from prospective population studies on the association between egg consumption and risk of T2D. OBJECTIVE: We investigated the association between egg consumption and risk of incident T2D in middle-aged and older men from eastern Finland. DESIGN: The study included 2332 men aged 42-60 y in 1984-1989 at the baseline examinations of the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor Study. Dietary intakes were assessed with 4-d food records at baseline. Incident T2D was assessed by self-administered questionnaires; by fasting and 2-h oral-glucose-tolerance-test blood glucose measurement at re-examination rounds 4, 11, and 20 y after baseline; and by record linkage to a hospital discharge registry and reimbursement register of diabetes medication expenses. Cox proportional hazards regression analyses were used to estimate associations with the risk of incident T2D. Associations with the metabolic risk markers at baseline and at the 4-y examinations were analyzed by ANCOVA. RESULTS: During an average follow-up of 19.3 y, 432 men developed T2D. After adjustment for potential confounders, those in the highest compared with the lowest egg intake quartile had a 38% (95% CI: 18%, 53%; P-trend across quartiles <0.001) lower risk of incident T2D. Analyses with metabolic risk markers also suggested an inverse association with fasting plasma glucose and serum C-reactive protein but not with serum insulin. The associations between cholesterol intake and risk of T2D, plasma glucose, serum insulin, and C-reactive protein were mainly nonsignificant, especially after accounting for egg consumption. CONCLUSION: Higher egg intake was associated with a lower risk of T2D in this cohort of middle-aged and older men.