The Effects of Exercise Therapy Moderated by Sex in Rehabilitation of COVID-19

Abstract BackgroundPulmonary rehabilitation serves as a key component in the recovery of COVID-19 and standardized exercise therapy programs in pulmonary rehabilitation have been shown to significantly improve physical performance and lung function parameters in post-acute COVID-19 patients. However, it has not been investigated if these positive effects are equally beneficial for both sexes, especially considering a more severe physical impact of COVID-19 in men when compared to women. Therefore, the purpose of this study was to analyze outcomes of a pulmonary rehabilitation program with respect to sex differences, in order to identify sex-specific pulmonary rehabilitation requirements.MethodsData of 233 patients were analyzed before and after a three-week standardized pulmonary rehabilitation program. Patients were admitted to rehabilitation due to post-acute COVID-19 illness and staged using the COVID-19 Severity Scale by Huang et al. (2021). Lung function parameters were assessed as part of the clinical routine using spirometry (ICmax, maximal inspiratory capacity) and body plethysmography (FVC, forced vital capacity; FEV1, forced expiratory volume in the first second) and functional exercise capacity was measured by the Six-Minute Walk Test (6MWT). For the comparison of lung function and walking parameters by sex, Welch-ANOVA was used, as results of Levene's test suggested significant heteroscedasticity regarding the investigated parameters (p > 0.05). When comparing post-treatment 6MWT, FEV1 and FCV to corresponding reference values, paired t-tests were used.ResultsAt post-rehabilitation, ICmax, FVC, FEV1 and 6MWT has been improved in both sexes. Females showed a significantly smaller improvement in FEV1 and ICmax (F = 5.86, ω2 = .02; p < 0.05) than males. There was no statistically significant difference in FVC and 6MWT performance improvements between men and women. After the rehabilitation stay, females made greater progress towards reference values of 6MWT (T(231) = -3.04; p < 0.01) and FEV1 (T(231) = 2.83; p < 0.01) than males.ConclusionsSex differences in the improvement of lung function parameters seem to exist when completing a three-week pulmonary rehabilitation program and should be considered when personalizing standardized exercise therapies in pulmonary rehabilitation.Trial registrationthis study was registered in the German Clinical Trials Register (DRKS00026936) on 2021/10/19.