Systemic symptoms are common in sarcoidosis and are associated with a decreased quality of life. Excessive daytime sleepiness (EDS) is often associated with obstructive sleep apnea (OSA), but may be a systemic symptom independently associated with sarcoidosis. The aim of this study was to assess the relationship between sarcoidosis and EDS.
In a retrospective analysis, we compared sleepiness by the Epworth Sleepiness Scale score in 62 patients with sarcoidosis to 1,005 adults without sarcoidosis referred for polysomnography for suspicion of OSA. Linear regression models controlled for covariates. In a subgroup analysis of sarcoidosis patients, sleepiness scores and polysomnogram results were compared between those with normal and abnormal pulmonary function based on total lung capacity.
EDS was more common in sarcoidosis than in controls, and sarcoidosis remained an independent predictor of increased sleepiness after controlling for covariates. Compared to controls referred for polysomnography, fewer sarcoidosis patients had clinically significant OSA. However, among sarcoidosis patients, OSA was more severe in those with abnormal lung function.
Sarcoidosis is independently associated with EDS. Sleepiness may contribute to the morbidity of sarcoidosis, and should be followed even after treating for potentially co-existing OSA or depression. Abnormal lung function in sarcoidosis may contribute to OSA, although the mechanisms for this are not known.