Sleep-related groaning: prevalence and characteristics in a cohort of patients with suspected obstructive sleep apnea.

ABSTRACT

CONCLUSION: Nocturnal groaning has the same prevalence in patients referred for diagnosis of sleep-disordered breathing as among other populations referred for sleep studies. The respiratory tracings in these patients have a distinct appearance that is possible to recognize with a polygraphic recording and thereby prevent the pattern from being misdiagnosed as central apneas. OBJECTIVES: The aim of this study was first to estimate the prevalence of groaning in patients referred for diagnosis of sleep-related breathing disorders. Second, we wanted to describe the respiratory pattern in order to distinguish the patients from patients with sleep apnea. METHODS: This was a prospective study in 1004 patients, performed in the Sleep Unit in our ENT Department, during a 12 month period. RESULTS: Four patients were diagnosed with video polysomnography, and the diagnosis of nocturnal groaning was confirmed. The prevalence of groaning in our sleep laboratory was 0.4%. All the patients had a mild form of sleep-related disturbance, and all groaning episodes occurred during REM sleep. The groaning events appeared in clusters. The length of each groan varied between 4 and 38 s. The number of events in a period varied between 2 and 11, and the length of each groaning period ranged between 11 and 168 s.