Chronic insomnia remitting after maxillomandibular advancement for mild obstructive sleep apnea: a case series

Background

Chronic insomnia and obstructive sleep apnea are both common sleep disorders. Chronic insomnia is thought to result from stress-related physiologic hyperarousal (somatic arousal) that makes it difficult for an individual to fall or stay asleep. Obstructive sleep apnea is thought to result from obstructive respiratory events causing arousals, sleep fragmentation, and recurrent oxygen desaturation. Although the two disorders seem different, they predispose to the same long-term, stress-related illnesses, and when they occur in the same individual, each affects the other’s response to treatment; they interact. This report of three cases describes patients with both chronic insomnia and obstructive sleep apnea in whom the chronic insomnia remitted with no specific treatment following treatment of obstructive sleep apnea with maxillomandibular advancement.

Case presentations

Our three Caucasians patients each presented with severe, chronic insomnia associated with somatic arousal and fatigue occurring either alone, in association with bipolar disorder, or with temporomandibular joint syndrome. Polysomnography revealed that each patient also had mild obstructive sleep apnea, despite only one snoring audibly. One patient experienced a modest improvement in her somatic arousal, insomnia severity, and fatigue with autotitrating nasal continuous positive airway pressure, but the other two did not tolerate nasal continuous positive airway pressure. None of the patients received treatment for insomnia. All three patients subsequently underwent maxillomandibular advancement to treat mild obstructive sleep apnea and experienced prolonged, complete resolution of somatic arousal, chronic insomnia, and fatigue. The patient with bipolar disorder also experienced complete remission of his symptoms of depression during the 1 year he was followed postoperatively.

Conclusions

These three cases lend support to the hypothesis that chronic insomnia and obstructive sleep apnea share a pathophysiology of chronic stress. Among patients with obstructive sleep apnea, the stress response is directed at inspiratory airflow limitation during sleep (hypopnea, snoring, and inaudible fluttering of the throat). Therefore, when chronic insomnia and obstructive sleep apnea occur in one individual, aggressive treatment of obstructive sleep apnea may lead to a reduction in chronic stress that causes the patient’s chronic insomnia to remit.