Predictors of coronary artery calcium incidence and progression: The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

Background and aims: There are limited data on serial coronary artery calcium (CAC) assessments outside North American and European populations. We sought to investigate risk factors for CAC incidence and progression in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Methods: We included individuals with no prior cardiovascular disease and two CAC measurements in ELSA-Brasil. Incident CAC was defined as a baseline CAC of 0 followed by CAC >0 on the second study. CAC progression was defined according to multiple published criteria. We performed logistic and linear regression to identify risk factors for CAC incidence and progression. We also examined risk factor effect modification by baseline CAC (0 vs. >0). Results: A total of 2707 individuals were included (57% women, age 48.6 ± 7.7 years). Participants self-identified as white (55%), brown (24%), black (16%), Asian (4%) and Indigenous (1%). The mean period between CAC assessments was 5.1 ± 0.9 years. CAC incidence occurred in 282 (13.3%) of 2127 individuals with baseline CAC of 0. CAC progression occurred in 319 (55%) of 580 participants with baseline CAC >0. Risk factors for CAC incidence included older age, male sex, white race, hypertension, diabetes, higher BMI, smoking, lower HDL-C, higher LDL-C and triglycerides, and metabolic syndrome. Older age and elevated LDL-C were associated with CAC incidence, but not progression. Risk factors consistently associated with CAC progression were hypertension, diabetes, hypertriglyceridemia, and metabolic syndrome. On interaction testing, these four risk factors were more strongly associated with CAC progression as compared to CAC incidence. Conclusions: CAC incidence was associated with multiple traditional risk factors, whereas the only risk factors associated with progression of CAC were hypertension, diabetes, hypertriglyceridemia, and metabolic syndrome.