Prevalence and risk factors of asthma in dairy farmers: Ancillary analysis of AIRBAg

BACKGROUND

Prolonged occupational agricultural exposure is associated with an increase in asthma diagnosis. This study aimed to identify the prevalence and risk factors for asthma in dairy farmers.

METHODS

AIRBAg was a cross-sectional study including 1203 representative dairy farmers. They completed a self-administered questionnaire and underwent a health respiratory check-up. Referral to a pulmonologist was made for any participant with wheezing, dyspnoea, chronic bronchitis, a chronic cough or a FEV₁/FEV₆ ratio<80%. They underwent further examinations such as spirometry with a reversibility test. Controls (non-asthmatic dairy farmers and non-farm employees) were matched to each asthma case for sex and age (±5 years). The odds ratios (OR) between asthma and different risk factors were estimated using conditional multivariate logistic regression models.

RESULTS

Active asthma was diagnosed in 107 (8.9%) farmers. Compared with control dairy farmers, there was a positive association with family history of allergy (OR = 8.68; 95% CI [4.26-17.69]), personal history of eczema (OR = 3.39; 95% CI [1.61-7.13]), hay manipulation (OR = 5.36, 95% CI [1.59-18.01]), and a negative association with farm area (OR = 0.92; 95% CI [0.85-0.99]) and handling treated seeds (OR = 0.47; 95% CI [0.23-0.95]). Compared with control non-farm employees, there was a positive association between asthma and family history of allergy (OR = 95.82, 95% CI [12.55-731.47]).

CONCLUSIONS

The prevalence of active asthma in dairy farmers was somewhat higher than the rate observed in the general population but may be controlled by reducing exposure to airborne organic contaminants through occupational adaptions on farms.

Abstract B06: ING2 loss sensitizes KRAS-mutated NSCLC to WEE1 inhibition through regulation of CHK1 expression

ING2 (Inhibitor of Growth 2) is a tumor-suppressor gene involved in chromatin acetylation whose loss has been observed in nearly 60% of NSCLC. The loss of ING2 expression has been associated with the progression of tumor cells from G1 to S phase, replication stress and genomic instability. The intra-S and the G2-M phase checkpoints are mainly regulated by the cell cycle tyrosine kinase WEE1. Therefore, we hypothesized that the loss of ING2 expression could sensitize NSCLC to the WEE1 inhibitor MK-1175, according to a synthetic lethality model. In silico analysis of the cancer gene dependency map (shRNAi Achilles library v.2016) was used to explore gene interactions with ING2. Antiproliferative effects of drugs were tested in vitro with AlamarBlue and MTT assays in a panel of NSCLC cells lines with varied mutational status. Multiple functional approaches were taken to decrease ING2 expression in RAS-mutated NSCLC cell lines (si-RNA, LNA-gapmer, and CrispR-Cas9). Pharmacologic inhibition of ING2 epigenetic functions was achieved using the HDAC inhibitor SAHA. Cell cycle and apoptosis analysis were performed using flow cytometry according to a BrdU-Pi and Annexin V-PI protocols, respectively. Compusyn software was used to model MK-1775 and SAHA drug interaction. NSCLC cell lines with mutant RAS that expressed high levels of ING2 protein were more resistant to the antiproliferative effect of MK-1775 than similar lines with low levels of ING2. Colony formation assays were consistent with these results. Multiple functional assays reproducibly showed that downregulation of ING2 expression increased MK-1775 sensitivity in vitro. Similar results were obtained with pharmacologic disruption of ING2 from the HDAC-SIN3A complex using SAHA, where disruption conferred a higher antiproliferative effect to MK-1775. Interestingly, combination treatment induced cell cycle progression and synergic cell death through apoptosis in RAS-mutated cell lines nondeficient for ING2. Since the synergistic effect of SAHA and WEE1 inhibitor was shown to be dependent on CHK1 activity in a previous report, we checked whether ING2 and CHK1 expression could be linked. Using public database and functional assays, we indeed find that ING2 downregulation represses CHK1 transcription through a mechanism that remains to be elucidated. Collectively, these findings demonstrate that inhibition of WEE1 by MK-1775 could represent a therapeutic approach to more effectively target ING2-deficient RAS-mutated NSCLC. Moreover, HDAC inhibitors targeting ING2 epigenetic functions synergize with MK-1775, possibly through regulation of CHK1 transcription. Consequently, this combination therapy could also be a promising strategy in ING2-proficient RAS-mutated NSCLC.

Citation Format: Charles Ricordel, Subash Thalappilly, Jérome Archambeau, Angela Chan, Nancy Nixon, Benoît Desrues, Gwyn Bebb, Karl Riabowol, Rémy Pedeux. ING2 loss sensitizes KRAS-mutated NSCLC to WEE1 inhibition through regulation of CHK1 expression [abstract]. In: Proceedings of the AACR Special Conference on Targeting RAS-Driven Cancers; 2018 Dec 9-12; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(5_Suppl):Abstract nr B06.

[Lung metastases of pancreatic adenocarcinoma: Watch for the second train!]

Pulmonary metastases due to a pancreatic cancer are difficult to diagnose and demonstrate a wide range of radiological patterns. We report the case of a 37-year-old female patient, without past medical history, with multicystic lung disease in a context of chronic abdominal pain, fatigue and weight loss. After several months of diagnostic delay, pathological examination of surgical lung biopsies led to the diagnosis of secondary deposits of pancreatic cancer. The clinical and radiogical situation deteriorated quickly with the development of alveolar consolidation and Aspergillus superinfection was then diagnosed. This case illustrates the value of an early decision to undertake surgical lung biopsy in the work-up of multicystic lung disease when cancer is suspected. In addition, in the specific context of cancer, faced with clinical and/or radiological deterioration, it is essential to look for infection, particularly aspergillosis.

Prevalence and risk factors of chronic obstructive pulmonary disease in dairy farmers: AIRBAg study

BACKGROUND

The AIRBAg study was designed to assess the prevalence of chronic obstructive pulmonary disease (COPD) in dairy farmers and to define its associated risk factors.

METHODS

Between March 2012 and February 2017 randomly selected dairy farmers in the French region of Brittany were asked to complete a self-administered questionnaire and undergo an occupational health check-up with electronic mini-spirometry and standard spirometry. Those having one or more of the following features: chronic cough, chronic bronchitis, wheezing, dyspnea and/or a ratio FEV₁/FEV₆ < 80% were then referred to a pulmonologist for further check-up including spirometry with a reversibility test. Each COPD case was matched with three controls (dairy farmers and non-farm employees), for sex and age ( ± 5 years). Conditional multivariate logistic regression models were used to estimate the odds ratios between COPD occurrence and various risk factors.

RESULTS

The 1203 farmers examined included 525 (43.6%) who were "at risk of bronchial obstruction" and 432 (35.9%) of these saw the pulmonologist. This screening identified 16 (1.3%) cases of COPD, including eight non-smokers and five with an FEV₁ < 80% of predicted values. Their average age was 54.6 ( ± 7.7) years and 10 of them were men. None complained of illness before the study. Multivariate analyses revealed no significant occupational risk factors for COPD.

CONCLUSIONS

This unexpected result may be because Breton dairy farms began to modernize early (1950s), giving rise to conditions with much lower exposure to airborne contaminants.

Purification of a Tumoral Marker Recognized by Monoclonal Antibody Po66 and Associated with Human Lung Squamous Cell Carcinoma

Monoclonal antibody (MAb) Po66, a murine IgG1, was raised by immunization against human lung squamous cell carcinoma. When injected intravenously, Po66 showed prolonged retention in the tumor. It recognized an intracellular antigen. The human lung squamous carcinoma cell line SK-MES-1 expresses the antigen recognized by MAb Po66 and was used as a source of biological material for its purification. The SK-MES-1 cell line was labeled in culture with [35S]methionine and its lysate was immunoprecipitated with Po66 immobilized on Protein G-Sepharose. The precipitate contained three proteins (47, 50 and 69 kDa) absent in the controls. The 69 kDa polypeptide was further purified by anion exchange and immunoaffinity chromatographies. To date, no other tumor marker expressed in non-small cell lung cancer with these characteristics has been described and as such this marker is interesting for future use in immunotherapy and in diagnosis.

[Interstitial lung disease and pancreatic cancer: Series of two cases]

INTRODUCTION

Pancreatic cancer is often not diagnosed until at a metastatic stage at which point the prognosis is very poor. Pulmonary metastases are pleomorphic, often present at the time of diagnosis and can lead to the discovery of an asymptomatic primary disease.

CASE REPORT

We describe two cases aged 60 and 74 years, where imaging identified what was thought to be an interstitial lung disease but which was actually metastasis from pancreatic cancer. In the first case, CT showed multiple excavated pulmonary nodules but the presentation with medullary compression led rapidly to pathological diagnosis on bone lesions. In the second patient, a history of rheumatoid arthritis and the lack of abdominal symptoms led to an initial search for disease related to the rheumatoid disease. Histopathology, from lung and bone biopsies, enabled a correct diagnosis to be achieved.

CONCLUSION

Where atypical interstitial lung disease occurs, biopsy should be considered in order not to delay a diagnosis of cancer, especially pancreatic cancer.

Prise en charge des exacerbations : de la ville à l’hôpital

La Société de pneumologie de langue française définie l’exacerbation aiguë de bronchopneumopathie chronique obstructive comme une majoration des symptômes respiratoires au-delà des variations quotidiennes (en pratique, d’une durée ≥ 48 h ou justifiant une modification thérapeutique).

La cause de ces exacerbations est principalement infectieuse : virale (rhinovirus, virus influenzae et parainfluenzae, coronavirus, adénovirus et virus respiratoire syncytial) ou bactérienne (principalement, Haemophilus influenzae, Streptococcus pneumoniae et Moraxella catarrhalis). Elles peuvent également résulter de l’exposition à certains polluants : NO₂, SO₂, ozone et pollution particulaire (PM10 et PM2,5). Elle reste indéterminée dans près de 30 % des cas.

Les diagnostics différentiels incluent les pneumopathies infectieuses, les pneumothorax, les poussées d’insuffisance cardiaque et les embolies pulmonaires.

La présence de signes de gravité conditionne l’hospitalisation : signes d’insuffisance respiratoire aiguë, de choc ou de défaillance neurologique, mais aussi en cas de patient fragile, d’absence de soutien familial à domicile ou de réponse au traitement initial.

Le traitement consiste en une majoration des bronchodilatateurs, une kinésithérapie respiratoire, une antibiothérapie en cas d’expectoration franchement purulente. La prescription de corticoïdes systémiques ne doit pas être systématique. La dose recommandée est de 0,5 mg/kg sur une courte période (5–7 jours). Lors d’une hospitalisation, une oxygénothérapie et une thromboprophylaxie peuvent être instaurées. La ventilation non invasive est principalement indiquée en cas de persistance d’une hypercapnie malgré un traitement médical optimal. Que le patient soit pris en charge en ambulatoire ou en hospitalisation, une réévaluation clinique à 48–72 h est indispensable.

[The management of complicated parapneumonic effusions in France]

INTRODUCTION

There are no French guidelines for the management of complicated parapneumonic effusions. A national observational study was carried out to assess the main features of current clinical practice for this condition.

MATERIAL AND METHODS

A questionnaire was sent by email to the 1500 members of the Société de Pneumologie de Langue Française (SPLF) between 15th November and 15th December 2012.

RESULTS

There were 92 responders, i.e. a response rate of 6%. Of these, 87 physicians mentioned that they were involved in the management of patients with complicated parapneumonic effusions with a median number of cases of 10 per year (IQR: 5-20). Chest tube drainage was the main approach used for pleural fluid aspiration (n=51/87), followed by repeated thoracentesis (n=29/87) and early surgery (1/87). Five physicians answered both chest tube drainage or repeated thoracentesis and one physician either chest tube drainage or early surgery. Pleural fibrinolytics were never used by 20% of physicians, only in case of loculations by 70% and by 10% of respondents in all cases. Only 3 physicians combined fibrinolytics with DNAse. A double antibiotic dose was used by one third of physicians. All the physicians used respiratory physiotherapy during hospitalization and to aid recovery. Follow-up practices were heterogeneous.

CONCLUSIONS

The management of complicated parapneumonic effusions varies significantly in France. National guidelines may be helpful to define best practice and aid in its implementation.

[Parapneumonic pleural effusions: Epidemiology, diagnosis, classification and management]

Parapneumonic pleural effusions represent the main cause of pleural infections. Their incidence is constantly increasing. Although by definition they are considered to be a "parapneumonic" phenomenon, the microbial epidemiology of these effusions differs from pneumonia with a higher prevalence of anaerobic bacteria. The first thoracentesis is the most important diagnostic stage because it allows for a distinction between complicated and non-complicated parapneumonic effusions. Only complicated parapneumonic effusions need to be drained. Therapeutic evacuation modalities include repeated therapeutic thoracentesis, chest tube drainage or thoracic surgery. The choice of the first-line evacuation treatment is still controversial and there are few prospective controlled studies. The effectiveness of fibrinolytic agents is not established except when they are combined with DNase. Antibiotics are mandatory; they should be initiated as quickly as possible and should be active against anaerobic bacteria except for in the context of pneumococcal infections. There are few data on the use of chest physiotherapy, which remains widely used. Mortality is still high and is influenced by underlying comorbidities.

[Management of COPD exacerbations: from primary care to hospitalization]

The Société de pneumologie de langue française defines acute exacerbation of chronic obstructive pulmonary disease (AE COPD) as an increase in daily respiratory symptoms, basically duration ≥ 48h or need for treatment adjustment. Etiology of EA COPD are mainly infectious, viral (rhinovirus, influenzae or parainfluenzae virus, coronavirus, adenovirus and respiratory syncytial virus) or bacterial (Haemophilus influenzae, Streptococcus pneumoniae, or Moraxella catarrhalis). Pollutant exposure can also lead to AE COPD, such as NO2, SO2, ozone or particulates (PM10 and PM2.5). In 30% the etiology remains unknown. Differential diagnoses of AE COPD include infectious pneumonia, pneumothorax, acute heart failure and pulmonary embolism. Presences of signs of severity impose hospitalization: signs of respiratory distress, shock, acute confusion but also fragile patients, insufficient home support or absence of response to initial treatment. AE COPD treatments consist on increase in bronchodilators, chest physiotherapy, and antibiotics if sputum is frankly purulent. Systemic corticosteroids should not be systematic. Recommended dose is 0.5 mg/kg on short course (5-7 days). During hospitalization, oxygen supplementation and thromboprophylaxis could be prescribed. The main interest in non-invasive ventilation is persistent hypercapnia despite optimal medical management. During ambulatory management or hospitalization, clinical assessment at 48-72 h is mandatory.

[Long-term macrolide treatment in adult chronic bronchial diseases: benefits and limits]

Decreased frequency of pulmonary exacerbations, mainly related to immunomodulatory effects of macrolide antibiotics, has been demonstrated in bronchiectasis and chronic obstructive pulmonary diseases (COPD). Due to its tolerance, azithromycin is the antibiotic of choice for maintenance therapy at the dose of 250 mg per day or 500 mg × 3 per week (for body weight >55 kg). Maintenance therapy with macrolide could be proposed in selected patients with bronchiectasis or COPD with more than 3 acute exacerbations in the previous year or decreased lung function despite compliance with optimum treatment. The risk of sudden cardiac death with azithromycin is rare and controversial. It should be avoided in patients with a high baseline risk of cardiovascular disease, QT>450 msec, pulse rate>100 bpm and potential drug interactions, particularly those known to cause QT prolongation. It is recommended to search for hearing deficit (audiometry) and sputum culture positive for mycobacteria. Patients must also be aware that it can rapidly lead to macrolide resistance in commensal or pathogenic flora. Follow-up evaluation every 3 month can be proposed with medical history (hearing deficit) and electrocardiography. After one year, the treatment should be stopped in the absence of reduction in the frequency of exacerbations.

[Hydroxyurea-induced pneumonia]

INTRODUCTION

Hydroxyurea is an antimetabolite drug used in the treatment of myeloproliferative disorders. Common adverse effects include haematological, gastrointestinal cutaneous manifestations, and fever. Hydroxyurea-induced pneumonitis is unusual.

CASE REPORT

A female patient was treated with hydroxyurea for polycythemia vera. She was admitted 20 days after commencing treatment with a high fever, productive cough, clear sputum and nausea. A chest CT-scan showed diffuse ground-glass opacities. Microbiological investigations were negative. The symptoms disappeared a few days after discontinuation of the drug and rechallenge led to a relapse of symptoms.

CONCLUSION

Our case and 15 earlier cases of hydroxyurea-induced pneumonitis are reviewed. Two patterns of this disease may exist: an acute febrile form occurring within 1 month of introduction of hydroxyurea and a subacute form without fever. Even if uncommon, one should be aware of this complication of hydroxyurea.

Impaired functions of macrophage from cystic fibrosis patients: CD11b, TLR-5 decrease and sCD14, inflammatory cytokines increase

BACKGROUND

Early in life, cystic fibrosis (CF) patients are infected with microorganisms. The role of macrophages has largely been underestimated in literature, whereas the focus being mostly on neutrophils and epithelial cells. Macrophages may however play a significant role in the initiating stages of this disease, via an inability to act as a suppressor cell. Yet macrophage dysfunction may be the first step in cascade of events leading to chronic inflammation/infection in CF. Moreover, reports have suggested that CFTR contribute to altered inflammatory response in CF by modification of normal macrophage functions.

OBJECTIVES

In order to highlight possible intrinsic macrophage defects due to impaired CFTR, we have studied inflammatory cytokines secretions, recognition of pathogens and phagocytosis in peripheral blood monocyte-derived macrophages from stable adult CF patients and healthy subjects (non-CF).

RESULTS

In CF macrophage supernatants, concentrations of sCD14, IL-1β, IL-6, TNF-α and IL-10 were strongly raised. Furthermore expression of CD11b and TLR-5 were sorely decreased on CF macrophages. Beside, no difference was observed for mCD14, CD16, CD64, TLR-4 and TLR1/TLR-2 expressions. Moreover, a strong inhibition of phagocytosis was observed for CF macrophages. Elsewhere CFTR inhibition in non-CF macrophages also led to alterations of phagocytosis function as well as CD11b expression.

CONCLUSIONS

Altogether, these findings demonstrate excessive inflammation in CF macrophages, characterized by overproduction of sCD14 and inflammatory cytokines, with decreased expression of CD11b and TLR-5, and impaired phagocytosis. This leads to altered clearance of pathogens and non-resolution of infection by CF macrophages, thereby inducing an exaggerated pro-inflammatory response.

[An unusual cause of cystic lung disease: light chain deposition disease]

INTRODUCTION

Light chain deposition disease is a rare clinical entity characterized by deposition of monoclonal immunoglobulin light chains in organs. The kidneys are almost always affected, while the lung manifestations that have been reported, including nodular or diffuse disease, especially cystic lesions, are unusual.

CASE REPORT

We report the case of a 60-year-old man with a diffuse infiltrative lung disease characterized by numerous apical cysts. The diagnosis of light chain deposition cystic lung disease was obtained by surgical lung biopsy. Light chain deposits in the salivary glands were the only extrapulmonary manifestation. Despite 12 chemotherapy cycles, the patient's lung function and radiological appearances worsened.

CONCLUSION

This is the fourth case describing a cystic lung disease due to light chain deposition in the literature. It highlights the need for comprehensive investigations so as not to miss this rare cause of cystic lung disease, which appears to be related to a primary pulmonary lymphoproliferative disorder. The only treatment that appears to be effective is lung transplantation.

Which patients should be tested for viruses on bronchoalveolar lavage fluid?

Bronchoalveolar lavage (BAL) is a major diagnostic tool in lung diseases, including viral respiratory infections. We aimed to better define the situations where viral tests should be performed on BAL fluid (BALF). We retrospectively studied all cases where viral tests [immunofluorescence, immunocytochemistry, viral culture, and/or polymerase chain reaction (PCR)] were performed on BALF during a period of 1 year (2008) in our institution. We compared the characteristics of patients with virus-positive versus virus-negative BALF. Of the 636 BALF samples sent to the microbiology laboratory, 232 underwent viral tests. Of these, 70 (30 %) were positive and identified 85 viruses: herpes simplex virus (HSV)-1 (n = 27), cytomegalovirus (CMV, n = 23), Epstein–Barr virus (EBV, n = 18), human herpesvirus (HHV)-6 (n = 12), respiratory syncytial virus (RSV, n = 3), rhinovirus (n = 1), and adenovirus (n = 1). The variables associated with positive viral tests on univariate analysis were immunosuppression [human immunodeficiency virus (HIV), corticosteroids >10 mg/day for ≥3 weeks, or other immunosuppressive therapy], ground-glass attenuations on computed tomography (CT) scanning, late-onset ventilator-associated pneumonia (VAP), and durations of (i) hospital stay, (ii) intensive care unit (ICU) stay, and (iii) mechanical ventilation before BAL (p < 0.01 for each comparison). On multivariate analysis, only immunosuppression [odds ratio (OR) 6.4, 95 % confidence interval (CI) [2.8–14.3], p < 0.0001] and ground-glass attenuations (OR 3.7, 95 % CI [1.8–7.7], p = 0.0004) remained associated with virus-positive BAL. None of the viral tests performed on BALF for the initial assessment of diffuse infiltrative lung disease (n = 15) was positive. PCR improved the diagnostic yield of viral tests on BALF by 50 %. Testing for viruses on BALF should be mostly restricted to immunocompromised patients with acute respiratory diseases and/or patients with unexplained ground-glass attenuations on CT scanning.

[Pancytopenia in disseminated tuberculosis: Think of macrophage activation syndrome]

INTRODUCTION

The macrophage activation syndrome (MAS), also known as haemophagacytosis, is a non-specific clinical syndrome, which includes, among other things general debility, fever and hepatospleneomegaly. The most frequent pathological abnormalities are pancytopenia, hypertryglyceraemia, and hyperferrititinaemia. These clinical and biological criteria, which determine the severity of MAS, must be associated with a histological criterion - haemophagocytosis (with histiocytosis), which is usually medullary but can more rarely be splenic, hepatic or ganglionic. MAS can be primary or secondary. In the latter case, it is frequently associated with an infection of which tuberculosis is the most common.

OBSERVATION

We describe the case of a young immunocompetent patient who had disseminated tuberculosis complicated by MAS.

CONCLUSION

It is important to be aware of MAS, because its occurrence is associated with a poor prognosis and its optimal treatment, which requires a multidisciplinary approach, has not been fully defined. The optimum strategy in relation to specific aetiologies remains to be clarified.

[Swallowing disorders, pneumonia and respiratory tract infectious disease in the elderly]

Swallowing disorders (or dysphagia) are common in the elderly and their prevalence is often underestimated. They may result in serious complications including dehydration, malnutrition, airway obstruction, aspiration pneumonia (infectious process) or pneumonitis (chemical injury caused by the inhalation of sterile gastric contents). Moreover the repercussions of dysphagia are not only physical but also emotional and social, leading to depression, altered quality of life, and social isolation. While some changes in swallowing may be a natural result of aging, dysphagia in the elderly is mainly due to central nervous system diseases such as stroke, parkinsonism, dementia, medications, local oral and oesophageal factors. To be effective, management requires a multidisciplinary team approach and a careful assessment of the patient's oropharyngeal anatomy and physiology, medical and nutritional status, cognition, language and behaviour. Clinical evaluation can be completed by a videofluoroscopic study which enables observation of bolus movement and movements of the oral cavity, pharynx and larynx throughout the swallow. The treatment depends on the underlying cause, extent of dysphagia and prognosis. Various categories of treatment are available, including compensatory strategies (postural changes and dietary modification), direct or indirect therapy techniques (swallow manoeuvres, medication and surgical procedures).

Fatigue and respiratory disorders

OBJECTIVES

To analyze the factors at the origin of fatigue in respiratory disorders. To assess fatigue and its functional impact on patients affected from respiratory diseases. To evaluate the results of comprehensive care on fatigue and functional capacity.

MATERIALS AND METHODS

We systematically reviewed the literature in Medline and the Cochrane Library, using the following keywords: fatigue, respiratory disorders, questionnaire, evaluation, assessment, randomized controlled trial, meta-analysis.

RESULTS

Fatigue is a high frequency symptom (90%) and takes an important place, as much as dyspnea, in the genesis of the respiratory induced handicap. Its assessment is varied, according to the studies. It originates from multiple causes, as shown from clinical and experimental studies. The main treatment consists in rehabilitation, using physical exercises. Its efficacy is demonstrated on physical endurance, but is not clear in terms of general fatigue.

CONCLUSION

Although fatigue is very frequent complaint, along with a major disabling condition, the comprehensive assessment of fatigue, in respiratory disorders, including its physical and cognitive components, is not still really codified. Rehabilitation is the main treatment. Its efficiency has been demonstrated on the physical and functional components of fatigue. Its results on perceived fatigue remains to be evaluated.