RESUMO
OBJECTIVES: Human immunodeficiency virus (HIV) is associated with cardiovascular (CV) and autonomic dysfunction, however the effects of fitness on vascular and autonomic mechanisms in HIV disease are unknown. METHODS: We studied forty-eight subjects (40.4 +/- 4.2 years) in a cross-sectional design matched for age, gender, BMI, and fitness. Participants were assigned to 1 in 4 groups: 1) Healthy Unfit (HU), 2) Healthy Fit (HF), 3) HIV Positive Unfit (HPU), and 4) HIV Positive Fit (HPF). Fitness was assessed via open-circuit spirometry; arterial compliance and autonomic modulations were measured via applanation tonometry and power spectral analysis, respectively, and baroreflex sensitivity was obtained using the alpha index. RESULTS: Arterial compliance was augmented in HPF vs. HPU [7.4 +/- 1.9 mmHg x second vs. 4.4 +/- 1.7 mmHg x second (P = 0.006)]. Parasympathetic modulation was higher in HPF vs. HPU [2244.5 +/- 2997.6 msecond(2) vs. 489.1 +/- 552.9 msecond(2) (P < 0.05)]. Sympathetic modulation was lower in HPF vs. HU [4.7 +/- 5.0 mmHg(2) vs. 12.9 +/- 9.7 mmHg(2) (P < 0.05)]. Baroreflex sensitivity was higher in HPF vs. HPU [17.3 +/- 10.2 msecond/mmHg vs. 7.4 +/- 3.8 msecond/mmHg (P = 0.003)], and HPF vs. HU [17.3 +/- 10.2 msecond/mmHg vs. 6.2 +/- 3.0 msecond/mmHg (P = 0.004)]. CONCLUSIONS: Augmentations in arterial compliance and baroreflex sensitivity associated with fitness portent an improved CV and autonomic profile for HIV-positive individuals. Physical activity may be an adjuvant method to enhance the overall vascular health in HIV-compromised individuals.
