Análise de concordância do VO2pico predito pelo TC6min vs teste de esforço cardiopulmonar em pessoas vivendo com HIV

Abstract

INTRODUCTION: Cardiopulmonary exercise testing (CPET) is considered the gold standard for assessing cardiorespiratory fitness (CRF) and identifying peak oxygen consumption (VO2peak). However, in clinical groups such as People Living with HIV (PLHIV), the requirement for maximal effort may limit its feasibility. The 6-minute walk test (6MWT), requiring submaximal effort and being more accessible, appears to be of interest. Predictive equations can calculate VO2peak, but is the result consistent with the gold standard method in PLHIV? OBJECTIVE: To investigate whether the VO2peak identified through the 6MWT and predictive equation is consistent with the result found in CPET in PLHIV. METHODOLOGY: The study is characterized as an observational study, with a sample composed of 14 men living with HIV under antiretroviral therapy (ART). All had undetectable viral loads and had an average age of 41.39 ± 12.37 years. Participants visited the laboratory on two occasions: the 6MWT was performed on the first visit, and the CPET on a cycle ergometer coupled with a gas analyzer was conducted on the second visit. VO2peak by the 6MWT was calculated by a predictive equation, while VO2peak was identified by the maximal effort reached in CPET at voluntary exhaustion. RESULTS: A concordance analysis was conducted using the Bland-Altman plot. The mean difference between VO2peak obtained by the two methods was 16.85 (ml/kg/min) with confidence intervals, lower and upper, respectively, of [6.07–27.62]. A one-sample T-test showed a statistically significant difference in the mean differences (p=0.001). CONCLUSION: All participants except one fell within the confidence intervals, but it was noticeable that the difference was smaller when CRF was lower. On the other hand, when CRF was higher, the difference also increased. Thus, we conclude that VO2peak through a predictive equation should not be used as a measure in PLHIV as it may mask the actual VO2peak of this population. Ultimately, only PLHIV with low CRF could have a smaller difference in their respective VO2peak in CPET.