Comorbid insomnia and obstructive sleep apnea: challenges for clinical practice and research.

STUDY OBJECTIVES: To review studies examining the cooccurrence of insomnia and obstructive sleep apnea (OSA), explore evidence for the effect of OSA therapy on insomnia symptoms and the effect of insomnia treatments on breathing and sleep in patients with OSA, and discuss challenges in the evaluation and treatment of comorbid insomnia and OSA.

METHODS/RESULTS: Seven pertinent studies were identified that assessed the prevalence of comorbid insomnia and OSA or sleep disordered breathing. Four studies were identified that examined the effects of OSA treatment in patients with insomnia, and 8 studies were found that examined hypnotic use in patients with OSA or sleep disordered breathing. A high prevalence (39%-58%) of insomnia symptoms have been reported in patients with OSA, and between 29% and 67% of patients with insomnia have an apnea-hypopnea index of greater than 5. Combination therapy, including both cognitive behavior therapy and OSAtreatment, resulted in greater improvements in insomnia than did either cognitive behavior therapy or OSA treatment alone. The use of GABAergic nonbenzodiazepine agents has been associated with improvements in sleep and has little to no effect on the apnea-hypopnea index in patients with OSA.

CONCLUSIONS: Insomnia and OSA frequently cooccur. The optimal strategy for adequately treating comorbid insomnia and OSA remains unclear. Future research examining the impact of insomnia on continuous positive airway pressure therapy is needed. Given the substantial overlap in symptoms between insomnia and OSA, evaluation and treatment of these 2 conditions can be challenging and will require multidisciplinary collaboration among sleep specialists.