Durstenfeld MS; Division of Cardiology at ZSFG and Department of Medicine, University of California, San Francisco (UCSF), USA.
Wilson MP; Jankowski CM; Ditzenberger GL; Longenecker CT; Erlandson K

The Journal of infectious diseases [J Infect Dis] 2024 May 28.
Date of Electronic Publication: 2024 May 28.

Background: People with HIV (PWH) have lower exercise capacity compared to peers without HIV, which may be explained by chronotropic incompetence (CI), the inability to increase heart rate during exercise.
Methods: The Exercise for Healthy Aging Study included adults ages 50-75 with and without HIV. Participants completed 12 weeks of moderate intensity exercise, before randomization to moderate or high intensity for 12 additional weeks. We compared adjusted heart rate reserve (AHRR; CI <80%) on cardiopulmonary exercise testing by HIV serostatus and change from baseline to 12 and 24 weeks using mixed effects models.
Results: Among 32 PWH and 37 controls (median age 56, 7% female, mean BMI 28 kg/m2), 28% of PWH compared to 11% of controls had CI at baseline (p = 0.067). AHRR was lower among PWH (91 vs 101%; difference 10%, 95% CI 1.9-18.9; p = 0.02). At week 12, AHRR normalized among PWH (+8%, 95% CI 4-11; p < 0.001) and was sustained at week 24 (+5, 95%CI 1-9; p = 0.008) compared to no change among controls (95%CI -4 to 4; p = 0.95; pinteraction = 0.004). After 24 weeks of exercise, only 15% PWH and 10% of controls had CI (p = 0.70).
Conclusions: Chronotropic incompetence contributes to reduced exercise capacity among PWH and improves with exercise training.