Body Mass Index but not Physical Activity Level Moderates Lowered Cardiac Baroreflex Sensitivity in People Living with HIV.

Reduced cardiac baroreflex sensitivity (cBRS) is an autonomic marker associated with a worse cardiovascular prognosis. Whether cBRS is lowered in people living with HIV (PLHIV) is yet unclear, as well as potential moderator effects of body mass index (BMI) or physical activity (PA) level. The present study aims to compare the spontaneous cBRS in PLHIV . HIV-uninfected controls, and to determine among PLHIV the relationship between cBRS body mass index (BMI) and PA level. Total, upward (cBRS+), and downward (cBRS-) cBRS gains were assessed using the sequential method from beat-to-beat blood pressure at rest in 16 PLHIV (46.5±8.4 years) under antiretroviral therapy for at least 6 months, and 16 HIV-uninfected controls (CTL; 42.1±8.0 years). PA level was assessed by the Physical Activity Questionnaire (IPAQ short version) overall score. PLHIV showed lower total cBRS (8.7±3.1 . 15.3±7.7 ms.mmHg; < 0.01), cBRS+ (9.2±4.9 . 16.0±6.8 ms.mmHg; < 0.01) and cBRS- (9.5±4.9 . 15.3±9.3 ms.mmHg; < 0.01) . CTL. No between-group difference was found for BMI (PLHIV: 25.2±2.6 . CTL: 26.8±3.2 kg.m; > 0.05) or IPAQ score (PLHIV: 2.4±1.0 . CTL: 2.0±1.4; > 0.05). In PLHIV, total cBRS was inversely correlated BMI (r = -0.44; = 0.04), but not IPAQ score (r = 0.17; = 0.26). HIV infection may reduce spontaneous cBRS, which seemed to be moderated by higher BMI, but not PA level of PLHIV.