Evaluation of ventilatory and peripheral muscle function in post-COVID-19 syndrome

Abstract

Introduction: Patients with COVID-19 who required hospitalization over the course of the disease seem to have worse functional outcomes over the evolutionary course after the acute phase of COVID-19. The mechanisms involved in the genesis of these dysfunctions are still not clearly elucidated. Objective: The objective of the study was to evaluate the prevalence of muscle dysfunctions, including sarcopenia, in addition to the functional status in patients with post-COVID-19 syndrome. Methods: Crosssectional study in a convenience sample that recruited 262 volunteers after approval by CEP under number CAAE: 48074921.7.0000.5235. Of these, 195 patients were evaluated, three months after hospital discharge or three months after laboratory
diagnosis of COVID-19. All patients were evaluated by handgrip dynamometry, the 1 RM test and the quadriceps endurance test, in addition to the maximum static (PImax) and dynamic (S-index) respiratory pressures and the Post-COVID-19 functional assessment scale (PCFS). Prevalence were compared using Fisher's exact test. Continuous variables were compared using the Kruskal-Wallis test. A p<0.05 was considered significant with the mean differences contained within the 95% confidence interval (95%CI). Results: The sample consisted of adults and elderly (58.2 ± 19.14 years), mostly male (136 [69.76%]), overweight or obese grade I (median BMI = 30.2 [5 .78] kg/m2). Regarding lung function, the median (%predicted) [IQR] of FVC, FEV1/FVC, TLC, FRC and DLCO were 65 [19.4]; 98
[20.5]; 66 [15.6]; 58 [13.0]; and DLCO: 62[21.5], respectively. Patients who required Hospitalization represented 58% of the evaluated patients (n=114) with an average of hospitalization’s days of 25.03 ± 1.04 days. Of these, 81 patients required IMV (71.05%) with a mean duration of 17.87 ± 0.79 days. The overall prevalence of sarcopenia was 55.4%. Patients who required hospitalization had a prevalence of sarcopenia of 67% (n=76) while patients with COVID-19 who did not require hospitalization had a prevalence of 14% with an odds ratio of 12.7( p<.0001 [95%CI 6.04 – 26.82]). However, among hospitalized patients, those who required IMV have
an even higher prevalence of sarcopenia (67% [n=76] and 79%[n=64]; p < 0.001), with an odds ratio of 6.73 in relation to hospitalized patients who were not mechanically ventilated. Patients who required hospitalization showed reduced ventilatory function (mean difference of 32 cmH2O; 95%CI [24 – 40] , p< 0.001 and mean difference of 11.0 cmH2O; 95%CI[6.0 – 20.0] , p< 0.001) of the maximum
static (Pimax) and estimated dynamic (S-Index) inspiratory pressures, respectively. In addition, these patients also showed a reduction in peripheral muscle strength and endurance (HGS, MSd: mean difference of 11 kgs; 95%CI [8 – 14] , p< 0.001, T1RM:
mean difference of 10.0 kgs; 95%CI [5.0 – 15.0] , p< 0.001 and Endurance test: mean difference of 7.0 s; 95%CI [5.0 – 11.0] , p< 0.001). Conclusion: Our results expose that ventilatory and peripheral muscle dysfunctions are associated with the most severe forms of COVID-19 and that this has a negative impact on the post-COVID-19 functional status in these patients.