Abstract P377: Insulin Resistance is Associated With Carotid Intima-media Thickness in Non-diabetic Subjects: the ELSA-Brasil Cohort Baseline

Abstract

Background: Epidemiological studies have analyzed the association between carotid intima-media thickness (CIMT) and insulin resistance, glucose levels or glycated hemoglobin with mixed results. Objective: To evaluate the association between CIMT and homeostasis model assessment - insulin resistance (HOMA-IR), fasting and post-load plasma glucose and glycated hemoglobin in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline. Methods: We included 8,028 participants (aged 35-74 years) without diabetes or overt cardiovascular disease who had complete CIMT data at baseline. We built crude and adjusted linear and binary logistic models to evaluate the association between CIMT and (a) HOMA-IR; (b) fasting plasma glucose; (c) post-load plasma glucose; and (d) glycated hemoglobin. We also built post-hoc models, stratified by sex. Results: In the fully-adjusted linear models, only the association between CIMT (in mm) and HOMA-IR remained significant (table). Consistent with these results, only the association between the highest age- sex- and race-specific CIMT quartile and HOMA-IR was significant in the adjusted model (odds ratio [OR]: 1.10; 95% CI: 1.04 - 1.17). The association between HOMA-IR and the highest CIMT quartile remained significant in sex-specific analyses (OR: 1.10; 95% CI: 1.02 - 1.20 for men and OR: 1.10; 95% CI: 1.02 - 1.20 for women). We did not find an independent association between CIMT and glucose or glycated hemoglobin levels. Conclusion: We found a direct, independent association between HOMA-IR and CIMT in a large sample of non-diabetic men and women. Mechanisms unrelated to glucose homeostasis, as a direct effect of insulin on atherosclerosis or medial hypertrophy, may be involved in this association.