Reduction of exercise capacity in sarcoidosis in relation to disease severity

Abstract

Anastasios Kallianos,1 Paul Zarogoulidis,2 Fotini Ampatzoglou,2 Georgia Trakada,2,3 Elias Gialafos,4 Georgia Pitsiou,2 Athanasia Pataka,2 Lemonia Veletza,2 Konstantinos Zarogoulidis,2 Wolfgang Hohenforst-Schmidt,5 Dimitris Petridis,6 Ioannis Kioumis,2 Aggeliki Rapti112nd Pulmonary Department, Sotiria Chest Diseases Hospital, Athens, 2Pulmonary Department-Oncology Unit, “G Papanikolaou” General Hospital, Aristotle University of Thessaloniki, Thessaloniki, 3Pulmonary Laboratory, Therapeutic Clinic Alexandra Hospital, University of Athens, Athens, 4Heart Diseases Department Aiginitio Hospital, University of Athens, Athens, Greece; 5Medical Clinic I, “Fuerth” Hospital, University of Erlangen, Fuerth, Germany; 6Department of Food Technology, School of Food Technology and Nutrition, Alexander Technological Educational Institute, Thessaloniki, GreeceIntroduction: 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.Aim: 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.Method: 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).Conclusion: 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.Keywords: cardiopulmonary exercise testing, pulmonary function tests, exercise