RELATIONSHIPS AMONG OBESITY, CENTRAL ADIPOSITY AND AUTONOMIC CARDIAC MODULATION IN WOMEN
Obesity; anthropometric measures; autonomic cardiac function; cardiometabolic disorders.
We investigated to what extent anthropometric measures can predict autonomic cardiac modulation. Cross-sectional study with 65 apparently healthy sedentary women (age 18-45) divided into three groups (eutrophic, overweight and obese). We collected anthropometric measures including weight, height, and abdominal, waist and hip circumferences. Obesity and central adiposity were expressed as body mass index, waist-to-hip and waist-to-height ratios. Total body and trunk fat percentages were examined by dual-energy X-ray absorptiometry and results used as diagnostic criterion. Autonomic cardiac modulation was expressed by linear and non-linear measures of heart rate variability. All anthropometric measures yielded strong correlations with criterion results of body composition (above r=0.581, p<0.001). Waist circumference yielded the highest diagnostic accuracy for obesity (AUC 0.994 [95% CI 0.981, 1.000]) followed by waist-to-height ratio (AUC 0.993 [95% CI 0.977, 1.000]). Overweight group had lower parasympathetic activity than eutrophic (HFn.u MΔ = - 13.11 [95% CI, -25.88, -0.34], g = 0.65, CL = 68.1%). Obese presented even lower measure (HFn.u MΔ = -21.22 [95% CI, -31.89, -10.55], g = 1.17, CL = 79.2%). Sympathetic activity behaved on opposing direction (LFn.u MΔ = 13.06 [95% CI, 1.65, 24.47], g = 0.65, CL 67.9%, and LFn.u MΔ = 21.07 [95% CI, 10.32, 31.82], g = 1.15, CL 78.9%, respectively). Estimation equations presented adjusted R2 from 5.0% to 15.8%. Here we demonstrate that traditional anthropometric measures can predict autonomic cardiac modulation and simplify clinical risk stratification in nonsymptomatic, apparently healthy female population.