Age- and sex-specific associations between body mass index and subendocardial viability ratio

The subendocardial viability ratio (SEVR) is a non-invasive indicator of myocardial oxygen supply-demand balance and coronary perfusion. This study aimed to investigate the associations of age, body mass index (BMI), and sex with SEVR. This cross-sectional observational study included 3,286 adults (1,419 men and 1,867 women). Anthropometric measurements, laboratory parameters, blood pressure, and SEVR were obtained using standardized protocols. Participants were categorized according to World Health Organization criteria for Asian populations as normal weight (BMI ≤ 22.9 kg/m²), overweight (BMI 23.0–24.9 kg/m²), and obese (BMI ≥ 25.0 kg/m²). The prevalence of low SEVR was compared across age-, sex-, and BMI-stratified groups. Multivariable logistic regression analysis was performed to identify factors independently associated with low SEVR. SEVR declined progressively with advancing age and was significantly lower in participants aged 55–66 years and > 66 years than in those aged ≤ 39 years and 40–54 years (all p < 0.001). Estimated 10-year ASCVD risk scores increased significantly with age (all p < 0.001). Among overweight participants, the prevalence of low SEVR varied significantly across age groups, whereas differences across BMI categories were observed only among participants aged 40–54 years. Among men, overweight and obese participants exhibited significantly higher SEVR values and a lower prevalence of low SEVR than normal-weight participants, whereas no significant associations were observed among women. Multivariable logistic regression analysis identified male as an independent protective factor against low SEVR (OR = 0.458, 95% CI: 0.320–0.656; p < 0.05). SEVR decreases with advancing age and is inversely associated with estimated 10-year ASCVD risk. Age appears to have a stronger influence on low SEVR than BMI, and significant sex-specific differences exist in the relationship between BMI and SEVR. SEVR may serve as a non-invasive marker of cardiovascular health and risk stratification.