Coronary Plaque Volume and Atherosclerotic Burden in an Asymptomatic Population: The Bahia Heart Study – A Community-Based Cohort in Northeastern Brazil

Abstract Background: The burden and distribution of coronary atherosclerotic plaque volume in asymptomatic individuals remain understudied in diverse populations, particularly in low- and middle-income regions with unique ethnic admixture and cardiovascular risk profiles. This study aimed to quantify total and subtype-specific coronary plaque volumes using advanced imaging in a community-based cohort from Bahia, Brazil, and to explore associations with demographic, clinical, and lifestyle factors. Methods: The Bahia Heart Study is an ongoing prospective cohort of 2,500 asymptomatic adults aged 40-65 years, recruited from the general population in Porto Seguro and surrounding areas in Bahia, Brazil. Participants underwent coronary computed tomography angiography (CCTA) with artificial intelligence-guided quantitative analysis for plaque volume assessment, alongside coronary artery calcium (CAC) scoring and comprehensive evaluation of traditional risk factors (e.g., age, sex, hypertension, diabetes, dyslipidemia, smoking, obesity, and physical activity). Cross-sectional baseline data were analyzed to determine plaque volume distribution, prevalence of any plaque, noncalcified vs. calcified components, and high-risk features. Results: The cohort (mean age 54 years, 52% women, diverse ethnic admixture including significant African, European, and Indigenous ancestry) showed a substantial burden of subclinical atherosclerosis. Median total plaque volume was approximately 60 mm³ (interquartile range: 20-140 mm³), increasing with age and higher in men than women (P < 0.001). Any coronary plaque was present in ~52% of participants, with noncalcified plaque predominant in younger individuals. Prevalence of plaque volume ≥20 mm³ was 78% in men and 65% in women. Among those with CAC = 0, ~18% had detectable plaque. Independent predictors of higher plaque volume included older age, male sex, diabetes, hypertension, and abdominal obesity, with ethnic-specific patterns suggesting potential influences from regional lifestyle and genetic factors. Conclusions: This study reveals a notable prevalence and volume of coronary plaque in an asymptomatic Bahian population, highlighting the value of quantitative CCTA for early detection in primary prevention settings. Age- and sex-specific nomograms for plaque volume provide reference standards for this underrepresented region. Longitudinal follow-up will evaluate prognostic implications and inform tailored cardiovascular risk stratification in Northeastern Brazil.