Positive airway pressure therapy in patients with opioid-related central sleep apnea

This study aims to compare treatment response and adherence rate to positive airway pressure (PAP) in patients with opioid-related central sleep apnea (O-CSA) and idiopathic central sleep apnea (I-CSA).

We performed a retrospective chart over a 5-year period performed at a VA sleep center. Continuous PAP (CPAP) was prescribed initially for all participants. For those nonresponders (apnea hypopnea index (AHI) of >10/h), bi-level PAP (BiPAP) or adaptive servoventilation (ASV) was instituted upon provider's discretion. Adherence to therapy was checked with the built-in meter.

Thirty-four patients with O-CSA and 61 with I-CSA were included in the analysis. The two groups were comparable with respect to age, body mass index (BMI), Epworth Sleepiness Scale, and burden of comorbidities. The mean daily equivalent dose of morphine in the O-CSA was 168 mg (range 30-1,217 mg). In the O-CSA group, 24% of PAP-naïve patients responded to CPAP compared to 38% in the I-CSA group. BiPAP and ASV were comparable in eliminating central events in both O-CSA (66 versus 60 %) and I-CSA (93 versus 90%), respectively. Eight patients (24%) with O-CSA and six patients (10%) with I-CSA were considered nonresponders. The adherence rate was 48 and 24% in the I-CSA group compared to 23 and 18% in the O-CSA group at 3 and 12 months following initiation of effective treatment (p = 0.04 and p = 0.6).

The presence of O-CSA does not preclude an adequate response to CPAP. Adherence rate to PAP was poor in both the O-CSA and I-CSA groups. Further studies are needed to define optimal adherence rate and long-term benefits of PAP in CSA.