COPD Patients at Altitude Have Better Sleep Quality With Dexamethasone

By David Douglas

March 06, 2019

NEW YORK (Reuters Health) - Preventive dexamethasone treatment improved nocturnal oxygenation in certain chronic obstructive pulmonary disease (COPD) patients traveling to high altitudes, in a randomized controlled trial.

As Dr. Michael Furian explained to Reuters Health in an email, "There are concerns that patients with impaired pulmonary gas exchange by COPD are exposed to hazards caused by the reduced oxygen tension during high altitude travel."

Dexamethasone has been shown to prevent acute mountain sickness due to oxygen lack in healthy mountaineers, Dr. Furian of University Hospital Zurich in Switzerland and colleagues noted in JAMA Network Open, online February 22.

The glucocorticoid is also used to treat COPD exacerbations, and the researchers hypothesized that it might mitigate nocturnal hypoxemia in patients with mild to moderate COPD during a stay at high altitude.

The team enrolled 118 patients with a median lung function (FEV1) of 91% predicted and a peripheral capillary oxygen saturation (SpO2) measured by pulse oximetry at or beyond 92%. All lived in the Kyrgyz Republic at altitudes below 800 m.

The participants underwent baseline evaluation at 760 m, were taken by bus to a clinic at 3,100 m, and stayed there for two days and nights. They had earlier been randomized to oral dexamethasone twice daily or placebo. Treatment started 24 hours before their ascent and while staying at 3,100 m.

In the 58 patients receiving placebo, median nocturnal SpO2 at 760 m was 92% and their apnea/hypopnea index (AHI), which combines the average number of apneas and hypopneas that occur per hour of sleep, was 20.5. In the 60 who received dexamethasone, the corresponding values were 92% and 25.9.

During the first night at 3,100 m, the placebo group's SpO2 fell significantly to 84% and their AHI rose significantly to 39.4. In the active-treatment group, SpO2 also fell significantly (to 86%) but their AHI remained essentially unchanged at 24.7.

Overall, compared with placebo, dexamethasone reduced altitude-induced changes in Sp02 by a mean of 3% and reduced increases in AHI by 18.7 events. The differences were statistically significant, and the results were similar on the second day.

Patients receiving dexamethasone also perceived better sleep quality than patients receiving placebo, though the effects were only borderline significant. The mean difference with active treatment was 11% on the first night and 12% on the second.

Sixteen participants on dexamethasone (27.6%) had drug-induced hyperglycemia. There were no other relevant adverse effects.

The trial is "the first to provide evidence that preventive dexamethasone therapy starting before an altitude sojourn improves nocturnal oxygen saturation in the blood, prevents altitude-induced breathing instability with frequent apneas and improves sleep quality," said Dr. Furian.

"The results of this trial are good news for patients with COPD because they suggest that preventive dexamethasone treatment may serve as an alternative treatment for improving well-being during altitude travel if oxygen is not feasible," he added. "Since dexamethasone may increase blood glucose concentration it is not suitable for patients with diabetes."

Commenting by email, Dr. Peter Hackett, director of the Institute of Altitude Medicine, in Ridgway, Colorado, told Reuters Health the findings are "important for patients with mild to moderate COPD who do not require oxygen at their low-altitude homes, and do not need CPAP for obstructive sleep apnea."

Dr. Hackett, who was not involved in the study, added that the drug "was not compared to oxygen, which would work even better, but two pills a day is much more convenient and less expensive than providing oxygen. Dexamethasone is also very effective in preventing acute mountain sickness, a common problem with rapid ascent to altitudes over 8,000 feet."


JAMA Netw Open 2019.