Racial disparities in electrical and structural cardiac adaptation among adolescent athletes: A systematic review and meta-analysis.

BACKGROUND: In pediatric and adolescent athletes, there is a lack of understanding about the impact of factors such as race on the structural or cardiovascular adaptations in response to exercise which may unnecessarily disqualify athletes from the competitive sport. We hypothesized that race has an impact on cardiac adaptions in non-adult athletes. AIM: To explore the racial disparity in electrocardiographic (ECG) and echocardiographic (ECHO) parameters in healthy adolescent athletes. METHODS: A comprehensive electronic systematic literature search using MEDLINE database was performed from inception to September 20, 2024. Inclusion criteria included randomized or observational cohort studies that recruited adolescent competitive athletes in any sport discipline and compared between the Black and White races with an age range of 12-18 years. RESULTS: Of 723 records that were identified by the literature search, seven studies (n = 5036) were included. The mean age was 13.0-18.0 years old with male predominance. Black athletes had significantly longer PR interval [mean difference (MD) = 17.49 millisecond, 95%CI: 11.70-23.29] and shorter QRS complex duration (MD = -7.35 millisecond, 95%CI: -9.17 to -5.53) and corrected QT interval (MD = -4.95 millisecond, 95%CI: -7.69 to -2.22) than the White athletes. Black athletes were approximately four times more likely to have first-degree atrioventricular (AV) block, inverted T wave, ST-segment elevation, and left atrium (LA) enlargement than their White counterparts. In terms of ECHO parameters, Black athletes had significantly greater septal wall thickness (MD = 0.85 mm, 95%CI: 0.62-1.07), posterior wall thickness (MD = 1.07 mm, 95%CI: 0.36-1.78), relative wall thickness (MD = 0.03, 95%CI: 0.001-0.06), maximal wall thickness (MD = 1.05 mm, 95%CI: 0.28-1.83), and LA diameter (MD = 1.64 mm, 95%CI: 0.16-3.12). CONCLUSION: Race has an impact on the ECG and ECHO parameters that reflect cardiac adaptations in adolescent athletes. Black athletes tend to have an increased prevalence of distinct ECG changes such as first-degree AV block and T-wave inversions compared with their White counterparts. Despite having thicker septal and posterior walls, the overall prevalence of left ventricular hypertrophy did not differ between the races.