Obstructive Sleep Apnoea in Sarcoidosis

Sarcoidosis is a multisystemic granulomatous disease of unknown origin. Fatigue is a common problem in sarcoidosis affecting between 50% and 80% of patients, and thus represents a major impairment of their quality of life. The findings of recent studies suggest a high prevalence of obstructive sleep apnoea (OSA) in patients with sarcoidosis, estimating a range from 17% to 67%. Pathomechanisms leading to this increased OSA prevalence are still unclear, yet likely to be multifactorial including sarcoid myopathy and neuropathy leading to impaired integrity of the upper airways as well as corticosteroid induced obesity. While both diseases, Sarcoidosis and OSA, could lead to fatigue and excessive daytime sleepiness (EDS) the current managing strategies differ significantly. OSA patients are mostly treated with continuous positive airway pressure (CPAP) whereas sarcoidosis associated fatigue may require increased immunosuppressive therapy. Little is known about treatment of fatigue and sleepiness in patients suffering from both conditions.This study aims to close this knowledge gap and define prevalence of OSA in a swiss cohort with sarcoidosis patients. Therefore, we plan a prospective, observational, controlled study to investigate the prevalence of sleepiness, fatigue, life quality and obstructive sleep apnoea in patients with Sarcoidosis. Patients treated in the University Hospital Zurich due to sarcoidosis will be invited by letter to take part in this study. After confirmed consent and baseline assessments at the University Hospital Zurich, these patients will undergo a single night, in-home sleep study to assess possible OSA. Sleepiness and fatigue specific questionnaires and in-home respiratory polygraphy (oRP) are obtained in all subjects. To assess inflammation status and other conditions connected to sleepiness like hypothyroidism and anaemia, sarcoidosis patients will undergo blood sampling.