Sagittal abdominal diameter to triceps skinfold thickness ratio: a novel anthropometric index to predict premature coronary atherosclerosis.

OBJECTIVE We aimed to compare the accuracy of a novel index defined by us, as a ratio of Sagittal abdominal diameter (SAD) and triceps skinfold thickness (TSF) with other indices of adiposity for prediction of presence, severity and extension of premature coronary artery disease (CAD). METHODS A cross-sectional study was conducted on 238 younger patients (females <55 years; males <45 years) who underwent coronary angiography. Anthropometric indices including TSF, SAD, waist circumference, and hip circumference were measured before catheterization and body mass index, waist-to-hip ratio, abdominal diameter index, index of central obesity as well as our proposed index, SAD-to-TSF ratio, were calculated accordingly. Evaluation of severity and extension of coronary stenosis was by Gensini score and extent score, respectively. RESULTS After adjustment for age and sex in multivariate regression models, the SAD-to-TSF ratio was the best predictor for the presence (OR = 2.49, 95% CI = 1.44-4.30; p = 0.001) and extension (β = 1.10, p = 0.004) of premature CAD. TSF and the SAD-to-TSF ratio were the only indices that significantly predicted the Gensini score and the correlation remained significant even after adjustment for age and sex (β = -7.28, p < 0.0001 and β = 3.76, p < 0.0001, respectively). CONCLUSION We showed that our proposed index, SAD-to-TSF ratio, has a substantially better accuracy than do the known indices of obesity like body mass index, waist circumference, and waist-to-hip ratio for the prediction of premature CAD. Furthermore, our index was the only index that positively correlated with the severity of premature CAD.