Sleep disordered breathing in a cohort of patients with sporadic inclusion body myositis.

OBJECTIVE The aims of the study were: (1) to evaluate subjective sleep quality and daytime sleepiness in patients affected by sporadic inclusion-body myositis (IBM); (2) to define the sleep and sleep-related respiratory pattern in IBM patients. METHODS Thirteen consecutive adult patients affected by definite IBM were enrolled, six women and seven men, mean age 66.2 ± 11.1 years (range: 50-80). Diagnosis was based on clinical and muscle biopsy studies. All patients underwent subjective sleep evaluation (Pittsburgh Sleep Quality Index, PSQI and Epworth Sleepiness Scale, ESS), oro-pharingo-esophageal scintigraphy, pulmonary function tests, psychometric measures, anatomic evaluation of upper airways, and laboratory-based polysomnography. Findings in IBM patients were compared to those obtained from a control group of 25 healthy subjects (13 men and 12 women, mean age 61.9 ± 8.6 years). RESULTS Disease duration was >10 years in all. Mean IBM severity score was 28.8 ± 5.4 (range 18-36). Dysphagia was present in 10 patients. Nine patients had PSQI scores ≥ 5; patients had higher mean PSQI score (IBM: 7.2 ± 4.7, CONTROLS: 2.76 ± 1.45, p=0.005); one patient (and no controls) had EES>9. Polysomnography showed that IBM patients, compared to controls, had lower sleep efficiency (IBM: 78.8 ± 12.0%, CONTROLS 94.0 ± 4.5%, p<0.001), more awakenings (IBM: 11.9 ± 11.0, CONTROLS: 5.2 ± 7.5, p=0.009) and increased nocturnal time awake (IBM: 121.2 ± 82.0 min., CONTROLS 46.12 ± 28.8 min., p=0.001). Seven Patients (and no controls) had polysomnographic findings consistent with sleep disordered breathing (SDB). CONCLUSION Data suggest that sleep disruption, and in particular SDB, might be highly prevalent in IBM. SIGNIFICANCE Data indicate that IBM patients have poor sleep and high prevalence of SDB.