Effects of Positive Airway Pressure on Patients with Obstructive Sleep Apnea during Acute Ascent to Altitude

Abstract

Rationale: In acute ascent to altitude, untreated obstructive sleep apnea (OSA) is often replaced with central sleep apnea (CSA). In patients with obstructive sleep apnea who travel to altitude, it is unknown whether their home positive airway pressure (PAP) settings are sufficient to treat their obstructive sleep apnea, or altitude-associated central sleep apnea.Methods: Ten participants with positive airway pressure-treated obstructive sleep apnea, who reside at 1,320 m altitude, underwent polysomnography on their home positive airway pressure settings at 1,320 m and at a simulated altitude of 2,750 m in a hypobaric chamber. Six of the participants were subsequently studied without positive airway pressure at 2,750 m.Measurements and Main Results: At 1,320 m, all participants' sleep apnea was controlled with positive airway pressure on home settings; at 2,750, no participants' sleep apnea was controlled. At higher altitude, the apnea-hypopnea index was higher (11 vs. 2 events/h; P , 0.01), mostly due to hypopneas (10.5 vs. 2 events/h; P , 0.01). Mean oxygen saturations were lower (88 vs. 93%; P , 0.01) and total sleep time was diminished (349 vs. 393 min; P = 0.03). Four of six participants without positive airway pressure at 2,750 m required supplemental oxygen to prevent sustained oxygen saturation (as determined by pulse oximetry) less than 80%. Positive airway pressure also was associated with reduced central sleep apnea (0 vs. 1; P = 0.03), improved sleep time (358 vs. 292 min; P = 0.06), and improved sleep efficiency (78 vs. 63%; P = 0.04).Conclusions: Acute altitude exposure in patients with obstructive sleep apnea treated with positive airway pressure is associated with hypoxemia, decreased sleep time, and increased frequency of hypopneas compared with baseline altitude. Application of positive airway pressure at altitude is associated with decreased central sleep apnea and increased sleep efficiency.

BTS Clinical Statement on air travel for passengers with respiratory disease

“…The changes are more marked in those with severe OSAS. Use of CPAP at altitude is associated with decreased central sleep apnoea and increased sleep efficiency 116…”

“…Using hypobaric chamber simulation testing, studies have shown that there is an association between hypoxaemia, decreased sleep time and an increased frequency of hypopneas for patients with OSAS who are acutely exposed to high altitude. 116 There are further adverse effects on sleep and OSAS if alcohol 117 or sedatives 118 are taken.…”

“…Use of CPAP at altitude is associated with decreased central sleep apnoea and increased sleep efficiency. 116 Consideration must be given to the whole journey including the return flight. This is especially important if the flight involves an overnight element and patients expect to drive the next day.…”

Socioeconomic Inequities in Adherence to Positive Airway Pressure Therapy in Population-Level Analysis

“…We performed a bioinformatics-based study whereby de-identified data obtained from the national-level adherence database (EncoreAnywhere ® ™, Philips-Respironics, Inc., Murrysville, PA, USA) was geo-linked to publicly available de-identified data that provides median household income information by 5-digit ZIP code of residence contained in both datasets [22,23]. Similarly, information regarding altitude was obtained and geo-linked because there is data suggesting that central apneas are worsened by high altitude and in a population-level analysis such apneas could influence adherence adversely [18,24]. Institutional Review Board approval was obtained from the University of Arizona (Protocol #1609849884).…”