Obesity Phenotypes and Electrocardiographic Characteristics in Physically Active Males: CHIEF Study.

Metabolically unhealthy obesity (MUO) has been associated with surface electrocardiographic (ECG) left ventricular hypertrophy (LVH), left atrial enlargement (LAE), and inferior wave inversions (TWI) in the middle- and old-aged populations. However, the relationship between obesity phenotypes and these ECG abnormalities in physically active young adults is yet to be determined. A total of 2,156 physically active military males aged 18-50 in Taiwan were analyzed. Obesity and metabolically unhealthy status were, respectively, defined as the body mass index ≥27 kg/m and the presence of metabolic syndrome based on the ATPIII criteria for Asian male adults. Four groups were classified as the metabolically healthy non-obesity (MHNO, = 1,484), metabolically unhealthy non-obesity (MUNO, = 86), metabolically healthy obesity (MHO, = 376), and MUO ( = 210). ECG-LVH was based on the Sokolow-Lyon and Cornell voltage criteria, ECG-LAE was defined as a notched wave ≥0.12 s in lead II or a notch of ≥0.04 s, and inferior TWI was defined as one negative wave axis in limb leads II, III, or aVF. Physical performance was evaluated by time for a 3-km run. Multiple logistic regression analysis with adjustment for age, smoking, alcohol drinking, and physical performance was utilized to investigate the associations between obesity phenotypes and the ECG abnormalities. As compared to MHNO, MUNO, MHO, and MUO were associated with lower risk of Sokolow-Lyon-based ECG-LVH [odds ratios (OR) and 95% confidence intervals: 0.80 (0.51-1.25), 0.46 (0.36-0.58), and 0.39 (0.28-0.53), respectively; for trend <0.001], and with greater risk of ECG-LAE [OR: 0.87 (0.44-1.72), 2.34 (1.77-3.10), and 3.02 (2.13-4.28), respectively; for trend <0.001] and inferior TWI [OR: 2.21 (0.74-6.58), 3.49 (1.97-6.19), and 4.52 (2.38-8.60), respectively; for trend <0.001]. However, no associations between obesity phenotypes and Cornell-based ECG-LVH were found. In physically active young males, obesity was associated with higher risk of ECG-LAE and inferior TWI, whereas the risk between obesity and ECG-LVH might vary by the ECG criteria, possibly due to a high prevalence of exercise induced-LVH in military and greater chest wall thickness in obesity. The cardiovascular prognosis of ECG-LVH in physically active obese adults requires further study.