The following is a summary of “Chronotropic Incompetence among People with HIV Improves with Exercise Training in the Exercise for Healthy Aging Study,” published in the May 2024 issue of Infectious Disease by Durstenfeld et al.

HIV can limit exercise ability due to chronotropic incompetence (CI), which is the inability to increase heart rate during physical activity adequately.

Researchers conducted a retrospective study investigating whether exercise training improves CI in people with HIV (PWH).

They enrolled adults aged 50-75 in the Exercise for Healthy Aging Study, both with and without HIV. The participants underwent 12 weeks of moderate-intensity exercise, followed by randomization to either moderate or high intensity for another 12 weeks. Adjusted heart rate reserves (AHRR with CI <80%) were analyzed during cardiopulmonary exercise testing, comparing results by HIV status and examining changes from baseline to 12 and 24 weeks using mixed effects models.

The results showed that among the 32 people with HIV and 37 control subjects (median age 56, 7% female, mean BMI 28 kg/m²), 28% of PWH had CI at baseline compared to 11% of controls (P=0.067). The adjusted heart rate reserve (AHRR) was lower in PWH (91% vs. 101%; a 10% difference, 95% CI 1.9-18.9; P=0.02). However, after 12 weeks of exercise, AHRR in PWH improved (+8%, 95% CI 4-11; P<0.001) and remained improved at 24 weeks (+5%, 95% CI 1-9; P=0.008), whereas no significant changes were observed in controls (95% CI -4 to 4; P=0.95; P interaction = 0.004). Following 24 weeks of exercise, CI prevalence dropped to 15% in PWH and 10% in controls (P=0.70).

Investigators concluded that PWH has a lower capacity for exercise activity due to CI, which improved with exercise training.

Source: academic.oup.com/jid/advance-article-abstract/doi/10.1093/infdis/jiae284/7683794