Pulse Wave Velocity and Autonomic Modulation Across Physical Activity Levels in Youth: Evidence From the Epi-Family Health Study.

BACKGROUND AND OBJECTIVES: Cardiovascular risk factors originating in childhood and adolescence may persist into adulthood and increase cardiovascular morbidity and mortality. Arterial stiffness, measured by pulse wave velocity (PWV), and impaired cardiac autonomic modulation (CAM) are early indicators of cardiovascular dysfunction, yet their relationship during growth is not fully understood. The potential role of moderate-to-vigorous physical activity (MVPA) in this association also remains unclear. This study examined whether MVPA influences the association between PWV and CAM in children and adolescents. METHODS: This cross-sectional study included 169 participants (mean age 10.5 years; 69 girls). PWV was assessed using the Arteris AOP device. CAM was evaluated through heart rate variability indices (SDNN, RMSSD, LF, HF, SD1, SD2). MVPA was measured using the Actigraph GT3-X accelerometer. Associations between PWV and CAM were analyzed using quantile regression adjusted for sex, age, and body mass index (Model 1), with additional adjustment for MVPA (Model 2). RESULTS: PWV was inversely associated with RMSSD (β = -15.77; 95% CI: -31.15 to -0.40; p = 0.045) and SD1 (β = -13.15; 95% CI: -23.81 to -2.84; p = 0.033). After adjustment for MVPA, these associations were attenuated: PWV-RMSSD remained borderline significant (β = -14.08; 95% CI: -28.11 to -0.24; p = 0.049), while PWV-SD1 was no longer significant (p = 0.055). No associations were observed for SDNN, LF, HF, or SD2. CONCLUSION: Higher PWV was associated with lower parasympathetic modulation in youth, but this relationship was attenuated after accounting for MVPA. These findings suggest that physical activity may partially mitigate the adverse effects of arterial stiffness on autonomic function during early life.