Electrocardiographic abnormalities associated with obesity in adolescents and young adults: physiologic variants or true pathology? A cross-sectional study

Background Obesity is defined by the World Health Organization as abnormal or excessive fat accumulation that poses a risk to health. It has reached epidemic proportions globally and carries significant cardiovascular risk, particularly in adolescents and young adults. Electrocardiographic (ECG) changes are well documented in obese adults; however, the extent and nature of these changes in healthy obese and non-obese young people remain poorly characterized. This study aimed to determine whether obesity-related ECG abnormalities are confined to obese adolescents and young adults or are equally observed across other body mass index (BMI) categories. Methods A cross-sectional descriptive study was conducted among 172 apparently healthy participants aged 10 to 24 years, recruited using a multi-stage stratified random sampling method. Participants were categorized into three BMI groups (normal weight, overweight and obese) according to CDC-BMI percentile for age criteria. A 12-lead resting ECG was performed on each participant using a Grandfield Medical three-channel ECG machine with automated analysis secondarily validated by a clinician. Anthropometric, clinical, and biochemical parameters were also obtained. Data were analyzed using SPSS version 23.0, and a p-value below 0.05 was considered statistically significant. Results Females constituted 59.3% of participants (M: F ratio approximately 1:1.5), with a mean age of 18.1 years (SD 3.77) and mean BMI of 27.2 kg/m² (SD 5.74). ECG abnormalities were observed overall in 43% of participants after excluding physiologic variants. Statistically significant findings included prolonged P-wave duration consistent with left atrial enlargement ( p = 0.01), prolonged PR interval ( p = 0.025), and T-wave flattening in inferior and lateral leads ( p = 0.017). T-wave flattening was most prevalent in the normal BMI group (42%). Age-related differences were identified for pulse rate and early repolarization pattern (ERP), both were significantly higher in early adolescents aged 10 to 14 years ( p < 0.001). P-axis values were significantly higher in young adults aged 20 to 24 years than in middle adolescents aged 15 to 19 years ( p = 0.005). T-axis measurements was significantly greater in males than females ( p = 0.016). Other findings including arrhythmias, left ventricular hypertrophy, right ventricular hypertrophy, atrial enlargement, and early repolarization pattern (ERP) were observed but did not reach statistical significance across BMI groups. QTc interval and QRS voltage were normal across all groups. Conclusion The majority of ECG findings observed in this study are consistent with physiologic variants distributed across all BMI categories. These findings are not confined to obese individuals, which challenges the assumption that such ECG changes are obesity-specific. Early screening in this age group may assist in differentiating true cardiac pathology from normal physiological variants, which has normal healthy spectrum of body functions or structure and requires no treatment modality because it represent the natural range of human diversity. Clinical trial number Not applicable