Associations of anthropometric markers with arterio-venous ratio in the general population

Background Overweight and obesity are major contributors to the worldwide burden of cardiovascular diseases. Structural changes within the human retinal vasculature may reflect early cardiovascular aging. Purpose The aim of our analyses was to investigate the associations of traditional anthropometry markers, body composition and fat distribution with parameters of retinal fundoscopy in a population-based study. Methods We performed cross-sectional analyses of 3,162 participants (1,659 women, 52.5%) aged 20 to 82 years from the baseline examination of the second independent population-based cohort of the Study of Health in Pomerania (SHIP-TREND-0) realized between 2008 and 2012. The associations of anthropometric parameters (body height and weight, body mass index [BMI], waist circumference [WC], hip circumference [HC], waist-to-hip ratio [WHR], waist-to-height ratio [WHtR]), body composition (fat mass [FM] and relative fat-free mass [RFFM] assessed by bioelectrical impedance analysis), and fat distribution markers (subcutaneous adipose tissue [SAT], and visceral adipose tissue [VAT] from magnetic resonance imaging) with the arterio-venous ratio (AVR) were analyzed by multivariable linear and logistic regression models adjusted for age, sex and smoking status. All exposure variables were standardized in the regression models. The AVR was calculated from the measurements of the central retinal artery equivalent (CRAE) and the central retinal vein equivalent (CRVE), which reflect the estimated diameter of the central retinal artery and vein. CRAE and CRVE were measured by fundus photography and static vessel analysis of the central retina. Moreover, an AVR < 0.8 was defined as decreased AVR. Results While RFFM was positively associated with the AVR (ß=1.11; 95% confidence interval [CI]: 0.81 to 1.41; p<0.001), all the other markers were inversely associated with AVR. Specifically, VAT showed the strongest inverse association with AVR (ß= -1.07; 95% CI: -1.49 to -0.65; p<0.001). In line with these results, RFFM was associated with a 0.76 (95%CI: 0.68 to 0.86; p<0.001) lower chance for a prevalent decreased AVR, while VAT was associated with a higher chance for a prevalent decreased AVR (odds ratio [OR]=1.40, 95%CI: 1.20 to 1.63; p<0.001) (Table 1). Conclusions Our results substantiate evidence of a deleterious inverse association between body markers derived from fat content, composition and distribution with the arterio-venous ratio. Importantly, and oppositely to that, we found a beneficial positive association of fat-free mass with the arterio-venous ratio. Our findings suggest a health effect of fat-free mass and a detrimental influence of fat mass on the circulatory system.