Cardiorespiratory fitness is associated with inflammation and physical activity in HIV+ adults

Our objective was to examine the effect of a lifestyle diet and exercise intervention on cardiorespiratory fitness (CRF) and to examine predictors of change in CRF.

People living with HIV (PLHIV) are at increased risk for cardiovascular disease. CRF is a better predictor of cardiovascular disease-related mortality than established risk factors yet very little is known about CRF in PLHIV.

One-hundred and seven virally suppressed PLHIV were randomized to a group-based intervention to improve lifestyle behaviors or a control condition. All PLHIV maximal cardiorespiratory stress test to determine VO2 peak, VO2 at anaerobic threshold, and ventilatory efficiency/VCO2, at baseline and 6 months later. Participants wore an accelerometer to measure physical activity, completed waist-hip circumference measures, and had a fasting lipid profile, IL-6, and high sensitivity C-reactive protein analyzed. Generalized estimating equations were used to examine the effect of the intervention on CRF and predictors of change in CRF.

Participants were approximately 53 years old, 65% male (n = 70), and 86% African-American (n = 93). There was no effect of the intervention on markers of CRF over time (P > 0.05). After controlling for age, sex, waist-hip-ratio, the inflammatory biomarker IL-6 was inversely associated with a decline in both VO2 peak (P = 0.03) and VO2 at anaerobic threshold (P = 0.03). In addition, participants who walked an additional 10 000 steps per day had a 2.69 ml/kg per min higher VO2 peak (P = 0.02).

Despite HIV viral suppression, PLHIV had remarkably poor CRF and inflammation was associated with a clinically adverse CRF profile. However, increased physical activity was associated with improved CRF.