Egg consumption and risk of acute stroke in the Million Veteran Program

Abstract

Background: While observational data suggest a higher risk of coronary artery disease with frequent egg consumption, only limited and inconsistent data are available on the relation of egg consumption with stroke.

Objective: The primary objective was to assess whether egg consumption is associated with a higher risk of ischemic and hemorrhagic stroke among US veterans.

Methods: In a prospective cohort study of US veterans from the Million Veteran Program (MVP), egg intake was collected through a self-reported food frequency questionnaire at baseline. Incidence of stroke was ascertained via ICD9/ICD10 codes from the electronic health records. Multivariable Cox proportional hazard models were used to estimate the multivariable adjusted hazard ratios.

Results: A total of 233,792 veterans (91.6% men) were studied with a mean age of 65.6 ± 11.7 years. During a mean follow-up of 3.3 years, a total of 5740 cases of fatal and non-fatal ischemic stroke and 423 cases of fatal and non-fatal hemorrhagic stroke occurred. Median egg consumption was 2-4 eggs/week. Crude incidence rates for acute ischemic stroke were 6.5, 7.2, 7.1, 7.4, 8.0, 8.1, and 8.6 cases per 1000 person-years for egg consumption of <1/month, 1-3/month, 1/week, 2-4/week, 5-6/week, 1/day, and ≥2/day, respectively. Corresponding multivariable adjusted hazard ratios (95% CI) were 1.00 (ref), 1.10 (0.96-1.25), 1.09 (0.96-1.23), 1.10 (0.98-1.25), 1.16 (1.01-1.33), 1.20 (1.03-1.40), and 1.22 (1.03-1.45) controlling for age, sex, ethnicity, body mass index, diabetes, smoking, alcohol intake, modified DASH score, and education (p linear trend 0.0085). For hemorrhagic stroke, multivariable adjusted hazard ratios (95% CI) after controlling for age, sex, ethnicity, body mass index, modified DASH score, and level of education were 1.00 (ref), 1.28 (0.96-1.72), 1.22 (0.93-1.61), and 1.19 (0.88-1.61) for egg consumption of <1/week, 1/week, 2-4/week, 5+/week, respectively.

Conclusion: Our data are consistent with a positive association of egg consumption with acute ischemic stroke but not hemorrhagic stroke among veterans.

Keywords: Egg consumption; Epidemiology; Nutrition; Risk factors; Stroke.