Sex differences of post-Covid patients undergoing outpatient pulmonary rehabilitation

BACKGROUND

Following years of pandemic severe acute respiratory syndrome coronavirus 2 infections labelled Covid-19, long lasting impairment summarized as post-Covid syndrome (PCS) challenges worldwide healthcare. Patients benefit from rehabilitation programs, but sex specific aspects of improvement remain little understood. The aim of the study was to assess whether women and men differ in response to outpatient pulmonary rehabilitation for PCS.

METHODS

263 (54.4% female) patients partaking in outpatient pulmonary rehabilitation (OPR) due to PCS between March 2020 and July 2022 were included in a prospective observational cohort study. Outcomes were assessed at baseline and before discharge from OPR and included six-minute walking distance (6MWD), 1-second forced expiratory volume (FEV1), diffusion capacity for carbon monoxide, maximal inspiratory pressure (MIP), dyspnea (medical research council scale), and post-Covid functional status scale (PCFS). Sexspecific changes in outcomes following OPR were assessed by linear mixed model and presented as mean differences (MD) with 95% confidence intervals. Linear regression was applied to test whether 6MWD correlates with PCFS and the minimal clinically important difference (MCID) in 6MWD regarding an improvement of at least one point in PCFS was computed with logistic regression.

RESULTS

Significant improvement throughout OPR was observed for all outcomes (all p < 0.0001). Despite less severe Covid-19 infections, PCFS scores remained higher in females after OPR (p = 0.004) and only 19.4% of women compared to 38.5% of men achieved remission of functional impairment. At baseline as well as after OPR, females showed higher symptom load compared to men in dyspnea (p = 0.0027) and scored lower in FEV1 (p = 0.009) and MIP (p = 0.0006) assessment. Performance in 6MWD was comparable between men and women. An increase of 35 m in 6MWD was computed as minimal clinically important difference to improve functional impairment.

CONCLUSION

Both subjective symptoms such as fatigue and dyspnea and objective impairment in performance in pulmonary function were more frequently observed among women. Despite improvement throughout OPR in both women and men, the sex-gap in symptom load could not be closed as women less often achieved remission from functional impairment due to PCS. Intensified treatment of these symptoms should be considered in women undergoing rehabilitation for PCS.

Decreased phrenic nerve compound muscle action potential, inspiratory muscle strength, and exercise capacity after COVID-19

Objectives

Respiratory muscle weakness with higher ventilatory demands were reported even in patients recovering from only mild COVID-19 symptoms. Aim of this study was to assess the function of phrenic nerve and inspiratory respiratory muscle as well as cardiopulmonary exercise capacity in patients with prolonged exertional dyspnea after COVID-19 infection.

Methods

In this observational exploratory study, electrophysiological examination of the phrenic nerve, inspiratory muscle capacity as well as lung function test, 6-min walk distance (6MWD) and cardiopulmonary exercise test, have been performed in 22 patients post COVID-19 diagnosis (post-CoV).

Results

Exercise capacity (peak workload, Wpeak % predicted and peak oxygen uptake, VO2peak % predicted) were significantly affected in the post-CoV patients (61.8 ± 23.3 Wpeak % and 70.9 ± 22.3 VO2peak %). Maximum inspiratory pressure (MIP) was reduced (60.1 ± 25.5 mbar). In 6 of the 22 patients the electrophysiological response of the phrenic nerve was pathologically decreased (reduced compound muscle action potential, CMAP), while nerve conduction velocity (NCV) was normal, which corresponds to reduced muscle fiber contraction capacity. Positive relationships were demonstrated between 6MWD and MIP (rs = 0.88) as well as quality of life questionnaire (CRQ) and MIP (rs = 0.71) only in patients with reduced CMAP.

Discussion

Respiratory muscle weakness and exercise capacity is associated with reduced phrenic nerve CMAP without signs of neuropathy. This indicates that muscle fiber pathology of the diaphragm may be one pathophysiological factor for the prolonged respiratory symptoms after COVID-19 infections.

[Outpatient pulmonary rehabilitation]

BACKGROUND

Outpatient pulmonary rehabilitation (PR) plays a central role in the integrative care of patients with pulmonary diseases.

MATERIAL AND METHODS

The article gives an overview of the recent evidence on outpatient PR in various diseases, in various settings including the cost-effectiveness. This is based on a selective literature search in the PubMed and Medline databanks, current expert opinions and clinical experiences.

RESULTS

Early rehabilitation after exacerbation in COPD patients leads to a reduction of rehospitalizations (hazard ratio 0.83) and to a reduction of mortality (hazard ratio 0.63) over a period of 12 months. Telerehabilitation is a promising future perspective in specific settings. Recent publications on bronchiectasis, interstitial lung diseases and pulmonary hypertension could confirm the safety and feasibility of outpatient PR and the cost-effectiveness could be demonstrated. Also, the evidence for inpatient as well as outpatient PR settings for patients with post-COVID and long COVID is growing.

CONCLUSION

There is growing equivalence with respect to the evidence on PR, independent of whether it is carried out in an outpatient or inpatient setting.

Outpatient Pulmonary Rehabilitation in Patients with Long COVID Improves Exercise Capacity, Functional Status, Dyspnea, Fatigue, and Quality of Life

BACKGROUND

COVID-19 survivors face the risk of long-term sequelae including fatigue, breathlessness, and functional limitations. Pulmonary rehabilitation has been recommended, although formal studies quantifying the effect of rehabilitation in COVID-19 patients are lacking.

METHODS

We conducted a prospective observational cohort study including consecutive patients admitted to an outpatient pulmonary rehabilitation center due to persistent symptoms after COVID-19. The primary endpoint was change in 6-min walk distance (6MWD) after undergoing a 6-week interdisciplinary individualized pulmonary rehabilitation program. Secondary endpoints included change in the post-COVID-19 functional status (PCFS) scale, Borg dyspnea scale, Fatigue Assessment Scale, and quality of life. Further, changes in pulmonary function tests were explored.

RESULTS

Of 64 patients undergoing rehabilitation, 58 patients (mean age 47 years, 43% women, 38% severe/critical COVID-19) were included in the per-protocol-analysis. At baseline (i.e., in mean 4.4 months after infection onset), mean 6MWD was 584.1 m (±95.0), and functional impairment was graded in median at 2 (IQR, 2-3) on the PCFS. On average, patients improved their 6MWD by 62.9 m (±48.2, p < 0.001) and reported an improvement of 1 grade on the PCFS scale. Accordingly, we observed significant improvements across secondary endpoints including presence of dyspnea (p < 0.001), fatigue (p < 0.001), and quality of life (p < 0.001). Also, pulmonary function parameters (forced expiratory volume in 1 s, lung diffusion capacity, inspiratory muscle pressure) significantly increased during rehabilitation.

CONCLUSION

In patients with long COVID, exercise capacity, functional status, dyspnea, fatigue, and quality of life improved after 6 weeks of personalized interdisciplinary pulmonary rehabilitation. Future studies are needed to establish the optimal protocol, duration, and long-term benefits as well as cost-effectiveness of rehabilitation.

[S1 Guideline Post-COVID/Long-COVID]

The German Society of Pneumology initiated the AWMFS1 guideline Post-COVID/Long-COVID. In a broad interdisciplinary approach, this S1 guideline was designed based on the current state of knowledge.The clinical recommendation describes current post-COVID/long-COVID symptoms, diagnostic approaches, and therapies.In addition to the general and consensus introduction, a subject-specific approach was taken to summarize the current state of knowledge.The guideline has an expilcit practical claim and will be continuously developed and adapted by the author team based on the current increase in knowledge.

Management of patients with SARS-CoV-2 infections and of patients with chronic lung diseases during the COVID-19 pandemic (as of 9 May 2020) : Statement of the Austrian Society of Pneumology (ASP)

The coronavirus disease 2019 (COVID-19) pandemic is currently a challenge worldwide. In Austria, a crisis within the healthcare system has so far been prevented. The treatment of patients with community-acquired pneumonia (CAP), including SARS-CoV‑2 infections, should continue to be based on evidence-based CAP guidelines during the pandemic; however, COVID-19 specific adjustments are useful. The treatment of patients with chronic lung diseases has to be adapted during the pandemic but must still be guaranteed.

Abstract 4880: Disruption of STAT3 signaling promotes K-Ras induced lung tumorigenesis

Lung cancer related and unrelated to smoking is still leading cause of cancer deaths worldwide with an overall survival rate of 15%. Several genetic alterations have been associated with lung cancer: loss of tumor suppressor genes such as p53, INK4a, LKB1 and mutations/amplifications in several oncogenes like K-Ras, EGFR, or c-Myc. Most frequent smoking-related mutations impair GTP hydrolysis in K-Ras, an oncogene downstream of the EGFR pathway, causing persistent cell growth and proliferation in 20-30% of lung adenocarcinomas. Another important downstream effector of EGFR signaling is the signal transducer and activator of transcription (STAT)-3. STAT-3 regulates important pathways in tumorigenesis, through upregulation of genes encoding apoptosis inhibitors (Bcl-XL, Bcl-2, Mcl-1, survivin). In patient samples and NSCLC cell lines nuclear, phosphorylated STAT3 is enhanced and correlates with subsequent suppression of apoptosis of NSCLC tumors. However, the role of STAT-3 in lung cancer in vivo has not yet been established. In order to investigate the role of STAT-3 in lung tumors, we have established a genetic mouse model that allows inducing K-RasG12D-dependent lung tumors and simultaneously genetically ablating STAT-3. Survival analysis of this model showed a significant advantage of K-RasG12D male mice harbouring STAT-3 compared to K-RasG12D mice lacking one or both alleles of Stat-3, indicating a hapoloinsufficient tumor suppressor role in oncogenic K-RasG12D tumor formation. Furthermore, animals with deleted STAT-3 and activated K-RasG12D have a significant increase in tumor burden and develop more adenomas and adenocarcinomas than age-matched animals, harbouring only oncogenic K-RasG12D. This data suggest that disruption of STAT-3 signaling promotes tumorigenesis in K-Ras induced tumors. We are currently investigating the molecular and cellular mechanisms responsible for this observation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4880. doi:1538-7445.AM2012-4880

Recruitment of Mycobacterium tuberculosis specific CD4+ T cells to the site of infection for diagnosis of active tuberculosis

Accurate and early diagnosis of active tuberculosis (TB) is problematic as current diagnostic methods show low sensitivity (acid-fast bacilli smears), are time-consuming (culture of biological samples) or show variable results [Mycobacterium tuberculosis (MTB)-specific PCR].

OBJECTIVES

In the course of infection, MTB-specific T cells clonally expand at the site of infection and may thus be used as diagnostic marker for active disease.

DESIGN

In this cohort study, the frequency of MTB-specific, interferon (IFN)-gamma expressing CD4(+) T cells obtained from peripheral blood and the site of disease in 25 patients with suspected TB was assessed (n = 11, bronchoalveolar lavage; n = 7, pleural fluid; n = 1, ascites; n = 1, joint fluid; n = 5, cerebrospinal fluid).

RESULTS

Amongst 15 patients who showed proven active TB infection, a striking increase of MTB-specific T cells was detected at the site of infection compared with peripheral blood (median increase: 28.5-fold, range: 7.25-531 fold; median of IFN-gamma-producing CD4(+) T cells from blood: 0.02%, range: 0-0.52%; median of IFN-gamma-producing CD4(+) T cells from the site of infection: 1.81%, range: 0.29-6.55%, P < 0.001).

MAIN OUTCOME MEASURE

Recruitment of MTB-specific T cells to the site of infection yielded a sensitivity of 100% and specificity of 90%, irrespective of the compartment affected.

CONCLUSIONS

The accumulation of MTB-specific T cells at the site of infection may prove as useful diagnostic marker for an accurate and rapid diagnosis of active TB.

Impact of Exercise Capacity on Myocardial High-Energy Phosphate Metabolism

31-Phosphorous magnetic resonance spectroscopy (31P MRS) is a unique tool to investigate IN VIVO high-energy phosphates (HEP) in the human heart. We hypothesized that physical capacity may be associated with myocardial HEP status. Healthy, male volunteers (n = 105, mean age 51 +/- 7 years) underwent bicycle ergometry with a stepwise increasing workload to determine maximal working capacity (MWC). Heart rate (HR) and blood pressure (BP) were measured continuously during exercise and 4 minutes of recovery. Further 31-Phosphorous 2-dimensional chemical shift imaging (31P 2D CSI) MRS was performed to assess myocardial HEP metabolism by determining phosphocreatinine to beta-ATP ratios (PCr/b-ATP) using a 1.5 tesla scanner. Volunteers with MWC > 230 Watt had significantly higher PCr/b-ATP ratios than those with MWC < 200 Watt (1.93 +/- 0.36 vs. 1.59 +/- 0.35; p < 0.001). Additionally, those with a recovery systolic (S)BP < 195 mmHg had significantly higher ratios than those with a recovery SBP > 195 mmHg (1.74 +/- 0.3 vs. 1.51 +/- 0.2; p < 0.05). We observed a linear correlation between the PCr/b-ATP ratio and MWC (r = 0.411; p < 0.001) and recovery SBP (r = - 0.290; p < 0.01). After statistical correction for age, these correlations remained significant. In this study, we observed a correlation of parameters of physical fitness determined by bicycle exercise testing and cardiac PCr/b-ATP ratios.