Depressive Symptoms before and after Treatment of Obstructive Sleep Apnea in Men and Women.

STUDY OBJECTIVES

To determine prevalence of depressive symptoms in obstructive sleep apnea (OSA) and the impact of OSA treatment on depression scores.

METHODS

Consecutive new patients referred for investigation of suspected OSA were approached. Consenting patients completed a patient health questionnaire (PHQ-9) for depressive symptoms when attending for laboratory polysomnography. Those with moderate/severe (apneahypopnea index [AHI] ≥ 15 events/h) and/or symptomatic mild OSA (AHI 5-14.99 events/h) were offered continuous positive airway pressure (CPAP) therapy. PHQ-9 was repeated after 3 months of CPAP with compliance recorded. Of a maximum PHQ-9 score of 27, a cut point ≥ 10 (PHQ-9 ≥ 10) was used to indicate presence of clinically significant depressive symptoms.

RESULTS

A total of 426 participants (243 males) were recruited. Mean ± standard deviation body mass index (BMI) was 32.1 ± 7.1 kg/m2 and AHI 33.6 ± 28.9 events/h. PHQ-9 was 10.5 ± 6.1 and independently related to AHI (p < 0.001) and BMI (p < 0.001). In those without OSA, PHQ-9 ≥ 10 was more common in women, but no gender difference was evident with OSA. Of 293 patients offered CPAP, 228 were compliant (mean nightly use > 5 h) over 3 months of therapy. In them, with therapy, AHI decreased from 46.7 ± 27.4 to 6.5 ± 1.6 events/h, PHQ-9 from 11.3 ± 6.1 to 3.7 ± 2.9 and PHQ-9 ≥ 10 from 74.6% to 3.9% (p < 0.001 in each case). Magnitude of change in PHQ-9 was similar in men and women. Antidepressant use was constant throughout.

CONCLUSIONS

Depressive symptoms are common in OSA and related to its severity. They improve markedly with CPAP, implying a relationship to untreated OSA.