Chronic insomnia, postmenopausal women, and sleep disordered breathing: part 1. Frequency of sleep disordered breathing in a cohort.

OBJECTIVES: A cohort of postmenopausal women complaining of chronic insomnia for over 6 months and free of hypnotic intake was recruited mostly from the community. Three hundred and ninety-four women were included. The following questions were addressed: How many presents sleep disordered breathing (SDB)? Which type of SDB (upper airway resistance syndrome [UARS] or obstructive sleep apnea syndrome [OSAS]) is the most frequent? Is there a specific upper airway anatomical abnormality in SDB patients predisposing to the syndrome?

POPULATION: Subjects were recruited in the community or referred by the Sleep Clinic and all had complaint of chronic poor sleep.

METHODOLOGY: First step. Questionnaires, visual analog scales, clinical interview, clinical evaluation with work-up, actigraphy, and ambulatory monitoring were used. Second step. Otolaryngologic evaluation, ambulatory sleep monitoring, and reading of results were used. Subjects negative for SDB at ambulatory monitoring had polysomnography (PSG) with pressure transducer/nasal cannula system and esophageal manometry measurements.

RESULTS: Population. Three hundred and ninety-four individuals responded to all entry criteria. Ambulatory monitoring identified 194 subjects with OSAS. Two hundred individuals were not recognized with SDB and were submitted to PSG. This further testing showed that 68 subjects had normal breathing, 62 had UARS, and 100 mild OSAS. Based on otolaryngological evaluation, subjects were classified based on the presence or absence of narrow upper airway, and the location of narrowing was assessed.

CONCLUSION: A total of 326 postmenopausal women complaining of chronic insomnia had a SDB, usually with low apnea-hypopnea index (AHI). This total represents about 83% of the studied women. Questions of the role of SDB in the complaint of chronic insomnia are raised.