Evaluation of functional capacity, muscle function, lung function and quality of life in post-COVID-19 patients

Abstract

Introduction: Coronavirus disease 2019 (COVID-19) is part of one of the diseases caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).This is part of a group of viruses responsible for predominantly causing acute respiratory syndromes, which can range from mild symptoms to severe conditions, with hospitalization, need for mechanical ventilation and a significant mortality rate. Changes in the pulmonary functional pattern interfere with the clinical severity of the disease, putting the function of the respiratory muscles at risk, causing intolerance to physical exercise and directly impacting the quality of life (QoL). Importantly, patients recovering from COVID-19 may experience persistent and debilitating symptoms that are still present at least 12 weeks after the initial infection, constituting the so-called post-acute COVID-19 syndrome (PCS). Patients with PCS often have limitations in performing activities of daily living (ADLs). Considering that most ADLs are performed at submaximal levels of effort, the Glittre-ADL test (TGlittre) was designed to assess functional capacity during exercise. Objective: This study verified whether the TGlittre time is useful in the evaluation of non-hospitalized patients with sequelae resulting from COVID-19 and, secondarily, whether the TGlittre time is associated with measures of pulmonary function, muscle function, physical activity and HRQoL. Methods: A cross-sectional study with 37 women with PCS who underwent TGlittre. Pulmonary function tests and handgrip strength (HGS) and quadriceps strength (QS) measurements were performed. Additionally, they were submitted to the International Physical Activity Questionnaire (IPAQ), Post-COVID-19 Functional Status (PCFS) scale and Short Form-36 (SF-36) questionnaire. Results: The mean value of TGlittre time was 4.8 ± 1.1 min, which was 163.7 ± 39.7 % predicted. The TGlittre time correlated negatively with maximum inspiratory pressure (r = -0.391, P = 0.015), QS (r = -0.591, P = 0.0001) and HGS (r = -0.453, P = 0.005). There was a negative correlation of TGlittre time with forced vital capacity-FVC (r = -0.588, P = 0.0001) and diffusing capacity for carbon monoxide-DLco (r = -0.671, P < 0.0001). Additionally, we also observed significant correlations between the TGlittre time and various dimensions of the SF-36. In the stepwise forward regression analysis, DLco, QS, FVC and physical role limitations in SF-36 explained 70% of the TGlittre time variability. The results indicate that patients with PCS spend a lot of time to perform the TGlittre multitasking, thus, there is a relationship between the TGlittre time and respiratory and peripheral muscle strength, pulmonary function and HRQoL. Conclusion: A new sphere of clinical follow-up of these patients is awakened by this pandemic reality, thus being a growing demand. The need to understand, based on evidence, the post-infection changes and the importance of promoting the return to full functionality of these recovered patients is highlighted.