Objective: To assess the prevalence of insomnia symptoms in patients with objectively diagnosed sleep-disordered breathing (SDB).
Design: Retrospective medical chart review of a representative sample of patients with SDB.
Setting: University sleep-disorders clinic and laboratory.
Patients: Two hundred thirty-one patients with SDB were selected from a pool of approximately 2,000 patients with sleep disorders.
Measurements: Data were extracted from intake questionnaires and polysomnographic studies.
Results: Of 231 patients with SDB diagnoses, 115 patients reported no insomnia complaints (SDB-only patients) and 116 patients reported clinically meaningful insomnia complaints (SDB-plus patients). Compared to SDB-only patients, SDB-plus patients reported significantly worse mean sleep characteristics consistent with insomnia, including sleep latency (17 min vs 65 min), total sleep time (7.2 h vs 5.6 h), and sleep efficiency (92% vs 75%). SDB-plus patients experienced significantly more psychiatric disorders, cognitive-emotional symptoms, and physical and mental symptoms that disrupted or prevented sleep. SDB-plus patients also reported greater use of sedative and psychotropic medications and had significantly more primary complaints of insomnia, restless legs or leg jerks, and poor sleep quality despite having relatively similar referral rates for sleep apnea or complaints of loud snoring.
Conclusions: Problematic insomnia symptoms were reported by 50% of a representative sample of patients with objectively diagnosed SDB. Research is needed to determine the degree to which insomnia and related symptoms and behaviors interfere with SDB treatment.