Correlation between workload-indexed blood pressure response to exercise (SBP/MET slope) and clinical and echocardiographic parameters among normotensive Olympic athletes

Introduction: The workload-indexed systolic blood pressure response to exercise (SBP/MET slope) has been proposed as a novel parameter for evaluating abnormal blood pressure response to exercise (ABPR) and its potential risks. Aim of our study was to assess the association between SBP/MET slope and clinical and cardiac dimensional parameters in normotensive athletes. Methods: A cohort of 292 normotensive Olympic athletes (155 male, 53.1 %) underwent a pre-participation evaluation that included clinical, echocardiographic, and exercise-stress test parameters. The SBP/MET slope was calculated as the increase in systolic blood pressure indexed to metabolic equivalents achieved during maximal exercise. Athletes were stratified into quartiles based on their SBP/MET slope, and comparisons across quartiles were made. Results: Athletes in the highest SBP/MET slope quartile exhibited increased left ventricular wall thickness, i.e., interventricular septum (IVS) compared to those in lower quartiles (10.3 ± 0.9 vs. 9.5 ± 1.1, p = 0.014). Male athletes predominated in higher quartiles (p = 0.047), and endurance athletes were absent in the higher groups (p = 0.006). No differences were observed for systolic or diastolic function across quartiles. At multivariate analysis, SBP/MET slope was indipendently correlated to IVS (p = 0.040; R2 = 0.566, standardized beta coefficient = 0.368) and inversely correlated to W/Kg (p = 0.014; R2 = 0.566, standardized beta coefficient = −0.507). After a follow-up of 10.3 ± 2.6 years, 13.6 % of athletes in the highest quartile developed hypertension. Conclusion: Athletes with higher SBP/MET slope exhibited increased wall thickness and lower exercise capacity and showed higher risk for late-onset hypertension. Long-term follow-up studies are warranted to further elucidate its prognostic implications.