Sleep-disordered breathing in facio-scapulo-humeral dystrophy: A case-control study

Abstract

Background: Patients with severe facioscapulohumeral dystrophy (FSHD) are at risk of sleep-disordered breathing (SDB) which may comprise obstructive sleep apnea (OSA) or nocturnal hypoventilation (NH). Transcutaneous capnometry allows for detection of NH in patients with respiratory muscle weakness but concerning FSHD, capnometric data have not yet been published. Methods: We collected sleep study and capnometry results in 31 adult patients with proven FSHD and 31 insomnic control subjects. Results: OSA was present in 17 patients (55%), and 8 patients (26%) showed NH. NH would have been missed in up to 7/8 patients if onlyoxymetric criteria of hypoventilation had been applied. Capnographic measures were correlated with disease severity in FSHD patients as reflected by the Clinical Severity Score (CSS). Non-invasive ventilation (NIV) was initiated in 6 patients with NH and 3 patients with OSA. Positive airway pressure (PAP) treatment was started in 2 patients, and positional therapy was sufficient in 4 individuals. In patients initiated on NIV, gas exchange significantly improved in the very first night of treatment. Conclusions: SDB is common in adult patients with FSHD, and nocturnal carbon dioxide tension is associated with disease severity. Transcutaneous capnometry is superior to pulse oxymetry in detecting NH.