Impacto da força muscular respiratória no desempenho funcional em pacientes com hipertensão pulmonar: um estudo transversal observacional

Abstract

Introduction: Pulmonary hypertension (PH) is a pathophysiological disorder in which pulmonary vessels undergo changes that increase the mean pulmonary arterial pressure at rest (mPAP ≥ 20 mmHg), thereby impairing pulmonary blood flow. Due to the difficulty in blood passing through the lungs caused by increased vascular resistance, the right side of the heart experiences an overload as it needs to pump blood with greater intensity. Consequently, patients with PH present symptoms such as exertional dyspnea, fatigue, and muscle weakness, which affect their functionality and quality of life. Objective: To analyze the correlation between functional performance in the 1-Minute Sit-to-Stand Test (1MSTS) and respiratory muscle strength in patients with Pulmonary Hypertension. Methodology: This is a crosssectional observational analytical study that included individuals aged 18 to 75 years. Participants were divided into the PH Group, with a clinical diagnosis of Pulmonary Hypertension, and the Control Group, composed of healthy individuals. The groups were matched by gender and age and underwent clinical and anthropometric evaluations. Pulmonary function was assessed using spirometry, and respiratory muscle strength was measured using maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), SNIP (nasal inspiratory pressure), and SNEP (nasal expiratory pressure) tests. Results: Seventeen individuals with PH were compared with 17 healthy individuals matched by gender and age (45.5 ± 15.6 years). The PH group showed significantly reduced values in pulmonary function, including both volumes and capacities, as well as respiratory muscle strength. Additionally, their performance in the 1MSTS was 30% lower than that of the control group. A moderate correlation was observed between MEP values and the number of repetitions in the 1MSTS (R = 0.56, p = 0.02) in the PH group. Conclusion: The PH group exhibited reduced values of pulmonary function and muscle strength, as well as lower functional performance. Moreover, a moderate relationship was found between reduced functional test performance and MEP, suggesting that assessing respiratory muscle strength may be useful for monitoring functional capacity and prognosis in patients with Pulmonary Hypertension