Abstract P171: Occupational, Sport and Leisure Physical Activity Have Contrasting Effects on Neural Baroreflex Sensitivity. The Paris Prospective Study III

Abstract

Background: Physical activity (PA) is beneficial for baroreflex sensitivity (BRS), but it is unclear whether the type of PA has similar effects on the neural (nBRS) or vascular (carotid stiffness) components of BRS. We sought to determine this in healthy adults from a community- based study via assessment of occupational (OPA), sport (SPA), leisure (LPA) and total PA (TPA). Methods: In 8649 adults aged 50 to 75 years, resting nBRS (estimated by low frequency gain, from carotid distension rate and heart rate) and carotid stiffness were measured by high-precision carotid echotracking. PA was self-reported using the Baecke questionnaire, which distinguishes OPA, SPA, LPA and TPA. The associations between PA and nBRS and carotid stiffness were quantified using multivariate linear regression analysis. Analyses were conducted separately in the working and non- working population. Results: In working adults (n=5039), OPA was associated with lower nBRS function (p=0.026) and borderline higher carotid stiffness (p=0.08). The associations between OPA and nBRS remained independent after additionally adjusting for SPA (p=0.03) and exaggerated exercise blood pressure (p=0.005), a predictor of future hypertension and cardiovascular events. When examining the type of OPA separately (i.e. lifting heavy loads, standing or walking at work) lifting heavy loads only was associated with impaired nBRS (p=0.048). When stratified by education, this association remained only in those with less than tertiary education. SPA was associated with higher nBRS (p=0.0005) and borderline lower carotid stiffness (p=0.052). Neither LPA nor TPA was associated with nBRS or carotid stiffness. In non-working adults (n=3610), SPA and TPA were both associated with lower carotid stiffness (p=0.012 and p=0.020), but not nBRS. LPA was not associated with either parameter. Conclusion: Occupation-related PA, in particular lifting heavy loads, is associated with lower nBRS function, especially in those with lower education. Higher amounts of sport-related PA are associated with higher nBRS and lower carotid stiffness.