title: Reduction of exercise capacity in sarcoidosis in relation to disease severity.
abstract: BACKGROUND
  Pulmonary function tests (PFTs) do not always predict functional limitations during exercise in sarcoidosis. Cardiopulmonary exercise testing (CPET) may facilitate the recognition of exercise intolerance in these patients.
  
  
  OBJECTIVE
  As relevant data in sarcoid patients are limited, the aim of the study reported here was to assess exercise capacity impairment during a maximal CPET and to evaluate potential correlations with PFT measurements and radiological stages of the disease.
  
  
  METHODS
  A total of 83 sarcoid patients consecutively referred for evaluation of exertional dyspnea over a 3-year period were studied retrospectively with PFTs, including spirometry, diffusing capacity of the lung for carbon monoxide (DLCO) and lung volumes, and CPET using standard protocol. Patients were grouped according to their radiological stages: Stage I (n=43), Stages II-III (n=31), and Stage IV (n=9).
  
  
  RESULTS
  Forced expiratory volume in 1 second, forced vital capacity, and total lung capacity were mildly impaired only in Stage IV (means ± standard deviation: 72.44±28.00, 71.33±26.70, and 59.78±21.72, respectively), while DLCO was mildly and moderately reduced in Stages II-III and IV (72.68±14.13 and 51.22±18.50, respectively) and differed significantly between all stages (I vs II-III: P=0.003, I vs IV: P=0.003, and II-III vs IV: P=0.009). Exercise capacity (as expressed by peak oxygen consumption <84% predicted) was decreased in 53% of patients (Stage I: 48%, Stages II-III: 52%, Stage IV: 78%); however, significant differences were noticed only between Stages I and IV (P=0.0025). Of note, significant correlations were found between peak oxygen consumption and DLCO (P=0.0083), minute ventilation (P<0.0001), oxygen pulse (P<0.0001), lactate threshold (P<0.0001), and peak ventilatory threshold (P<0.0001).
  
  
  CONCLUSIONS
  CPET could be considered a useful tool in exercise intolerance evaluation in sarcoid patients with mild PFT abnormalities. Exercise limitation in sarcoidosis may be attributed to both ventilatory and cardiocirculatory impairment.
authors: 2nd Pulmonary Department, Sotiria Chest Diseases Hospital, Athens, Greece.
authors: Anastasios
authors: A
authors: Kallianos
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors: Paul
authors: P
authors: Zarogoulidis
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors: Fotini
authors: F
authors: Ampatzoglou
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece ; Pulmonary Laboratory, Therapeutic Clinic Alexandra Hospital, University of Athens, Athens, Greece.
authors: Georgia
authors: G
authors: Trakada
authors: Heart Diseases Department Aiginitio Hospital, University of Athens, Athens, Greece.
authors: Elias
authors: E
authors: Gialafos
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors: Georgia
authors: G
authors: Pitsiou
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors: Athanasia
authors: A
authors: Pataka
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors: Lemonia
authors: L
authors: Veletza
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors: Konstantinos
authors: K
authors: Zarogoulidis
authors: Medical Clinic I, "Fuerth" Hospital, University of Erlangen, Fuerth, Germany.
authors: Wolfgang
authors: W
authors: Hohenforst-Schmidt
authors: Department of Food Technology, School of Food Technology and Nutrition, Alexander Technological Educational Institute, Thessaloniki, Greece.
authors: Dimitris
authors: D
authors: Petridis
authors: Pulmonary Department-Oncology Unit, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors: Ioannis
authors: I
authors: Kioumis
authors: 2nd Pulmonary Department, Sotiria Chest Diseases Hospital, Athens, Greece.
authors: Aggeliki
authors: A
authors: Rapti
keywords: cardiopulmonary exercise testing; exercise; pulmonary function tests