Abstract Body: Prior studies suggest associations between egg consumption, serum cholesterol levels, subclinical atherosclerosis and cardiovascular diseases (CVD). However, existing evidence remains controversial and limited. This study aimed to investigate the association between egg consumption, serum cholesterol profiles, subclinical atherosclerosis incidence, and CVD incidence among American Indians.

The Strong Heart Family Study (SHFS) is a multicenter, family-based, prospective cohort study of CVD among American Indian communities. We evaluated SHFS participants at the baseline between 2001 and 2003 (n=2147). Carotid ultrasounds were used to detect plaque at baseline and follow-up examinations between 2006 and 2009, with a median follow-up of 5.3 years (Q1, Q3: 4.8, 6.4 years). We identified 422 incident CVD events through 2022, with a median follow-up of 20.2 years (Q1, Q3: 16.6, 21.1 years). General linear mixed models were used to evaluate the association between egg consumption and changes in serum total cholesterol, triglycerides, LDL-C, and HDL-C levels. The analysis revealed very weak associations, with respective regression coefficients of -0.06, 0.0004, -0.02, and -0.05, and corresponding P-values of 0.005, 0.68, 0.05, 0.01. These findings suggested that egg consumption had minimal impact on serum cholesterol levels.

Shared frailty proportional hazards models were used to assess the association between egg consumption and subclinical atherosclerosis or CVD. We did not find a significant association between egg consumption and the development of carotid plaque. After adjusting for age, study site, hypertension, diabetes, and total caloric intake, the hazards ratios for incident CVD in the 2^nd, 3^rd, and 4^th quartiles of egg consumption were 0.77(95%CI: 0.56-1.05; P: 0.1), 0.74 (95%CI: 0.55-0.98; P: 0.04), and 1.12 (95%CI: 0.8-1.49; P: 0.42), compared to those in the 1^st quartile. Participants in the 3^rd quartile had a significantly lower risk of developing CVD.

This study found weak associations between egg consumption and serum cholesterol levels in the SHFS. Moderate egg consumption was associated with a significantly lower risk of developing CVD compared to the lowest consumption in this population. This association was not observed in the group with the highest egg consumption. Moderate egg consumption appeared to be a way for low-income communities to obtain essential nutrients, particularly proteins, without burdening on the cardiovascular system.