Fatigue in patients with sarcoidosis, compared with the general population Andreas Hinz, Ph.D. a, ⁎ , Michael Fleischer a , Elmar Brähler, Ph.D. a , Hubert Wirtz, M.D. b , Andrea Bosse-Henck, M.D. b a Department of Medical Psychology and Medical Sociology, University of Leipzig, 04103 Leipzig, Germany b Department of Respiratory Medicine, University of Leipzig, 04103 Leipzig, Germany Received 9 February 2011; accepted 16 May 2011 Abstract Objective: Fatigue is a significant symptom in sarcoidosis patients. The causes for this symptom are unclear. The aims of this study were to analyze age and gender differences in fatigue, compared with the general population, and to test the psychometric properties of two questionnaires measuring fatigue in sarcoidosis. Method: A sample of 1197 patients diagnosed with sarcoidosis was examined in Germany with the Fatigue Assessment Scale (FAS) and the Multidimensional Fatigue Inventory (MFI). Results: The percentages of patients exceeding the fatigue cut-offs were 70% (FAS) and 68% (MFI), respectively. While in the general population there is a nearly linear age trend (high fatigue scores with increasing age), among the patients there is only a very slight and nonlinear age trend. Female patients are more affected by fatigue than male patients, but this relationship is also true in the general population. Both questionnaires (FAS and MFI) are equally suited to test fatigue; their psychometric properties are good. They should not be replaced with a single question concerning tiredness. Conclusion: The comparison to norm data is highly recommended for the evaluation of age and gender differences. Compared with the general population, young sarcoidosis patients are especially affected by fatigue. © 2011 Elsevier Inc. All rights reserved. Keywords: Fatigue; Sarcoidosis; Psychometrics; Age differences; Gender differences 1. Introduction Sarcoidosis is an inflammatory disease, characterized by noncaseating granuloma. All organs in the body can be affected by sarcoidosis. Besides the lungs, the most often affected organs are the lymph nodes, skin and eyes. Symptoms often reported by sarcoidosis patients are pain, cough, breathlessness, reduced exercise capacity and arthralgia [1]. Generally, sarcoidosis patients report reduced health-related quality of life and mental health [2–6]. One symptom very often found in sarcoidosis patients is fatigue. Although fatigue is a common complaint in general medical practice, there are several diseases where fatigue is often found, e.g., cancer, multiple sclerosis, rheumatoid arthritis and depression [7]. Among sarcoidosis patients, fatigue was elevated in many studies. De Kleijn et al. [8] performed a systematic review, comprising 20 studies. The incidence rates of fatigue in these studies ranged from 33% to 100%. Four of the 20 studies had more than 200 patients, with the frequency of fatigue ranging from 71% to 80%. There are several questionnaires measuring fatigue. Among the 20 studies reported in the review on fatigue in sarcoidosis [8], the most often used questionnaire was the Fatigue Assessment Scale (FAS) [9]. Other fatigue scales adopted to assess sarcoidosis patients were the Energy and Fatigue Scale of the World Health Organization Quality of Life Assessment Instrument–100 (WHOQOL-100) [10], the Fatigue Scale (FS) [11] and the Functional Assessment of Chronic Illness Therapy–Fatigue (FACIT-F) [12]. Another fatigue questionnaire is the Multidimensional Fatigue Inventory (MFI). This instrument was developed by Smets et al. [13], especially for use in cancer patients. Although the MFI has not been validated in sarcoidosis patients, it seems Available online at www.sciencedirect.com General Hospital Psychiatry 33 (2011) 462 – 468 ⁎ Corresponding author. Tel.: +49 341 9718820; fax: +49 341 9718809. E-mail address: andreas.hinz@medizin.uni-leipzig.de (A. Hinz). 0163-8343/$ – see front matter © 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.genhosppsych.2011.05.009