Study: Oxygen prescription may not help some COPD sufferers
Some doctors might rethink prescribing oxygen to help certain patients with chronic lung disease based on results of a study published Wednesday.
The New England Journal of Medicine study showed that oxygen has no benefit for a subset of people with moderate forms of chronic obstructive pulmonary disease, a finding that could reduce how often doctors prescribe it.
The study was the first large, high-quality study of oxygen for COPD since the 1970s, when researchers determined the treatment extended lives of people with low levels of oxygen in their blood.
The new study analyzed patients with moderate levels of oxygen in their blood. The study divided 738 patients with moderate blood oxygen levels into two groups; one group used oxygen, and the other didn't. The study found those who received oxygen had the same rates of hospitalization and death as those who didn't.
Affecting an estimated 24 million Americans, COPD is the nation's third-leading cause of death, according to the National Institutes of Health. It affects primarily smokers or former smokers, impeding their lungs' ability to transfer oxygen from air to the blood.
Oxygen delivered from a tank through nasal prongs or a mask is the only treatment proven to prolong life in patients with severely decreased oxygen levels, according to pulmonologists. Doctors agree on its use for those patients, but their recommendations vary for patients with moderate levels of oxygen in their blood.
Some recommend the treatment for patients who register moderate blood oxygen levels while resting. Doctors more commonly recommend it for patients whose blood oxygen levels drop dangerously low during exercise. The study found no benefit for either of those patient groups, but study authors said the finding doesn't mean oxygen won't help anyone with a similar form of the disease, particularly when it comes to relief of symptoms.
“What that leaves us with, then, is that on a case-by-case basis, physicians who are in discussion with their patients who are symptomatic and (whose oxygen levels) drop down during exercise should be considered on a case-by-case basis,” said Dr. Frank Sciurba, director of UPMC's pulmonary function and exercise physiology laboratory and a co-author of the study.
Many people with COPD are undiagnosed, Sciurba said, making it difficult to estimate how many live with the moderate blood oxygen levels.
Some patients like using oxygen to avoid shortness of breath, while others are willing to endure breathing difficulties rather than haul around an oxygen tank.
The study, which involved 42 medical centers, notes that oxygen tanks aren't without dangers — five patients reported fires or burns, with one requiring hospitalization; 23 patients reported tripping over equipment, with two going to the hospital because of injuries.
Sciurba said the study could help reduce pressure on patients to use oxygen and doctors to prescribe it when patients don't want it.
“I think that a reasonable interpretation of this study is that patients who don't want it or don't feel they benefit from it, don't feel it improves the quality of life, that there is not a medical indication,” he said.
Sciurba said a pending update of the Global Obstructive Lung Disease Guidelines will incorporate the study's findings.
Dr. Tariq Cheema, an Allegheny Health Network pulmonologist who is co-director of the Breathing Disorders Center at the Wexford Health + Wellness Pavilion, said he is less convinced by the study's results. Cheema was not involved in the study.
“It's one of the studies out there that will be talked about for a while, but I don't think it changes much,” he said. “This kind of reinforces things that we already knew.”
The study helps show there isn't data to support using oxygen for comfort, Cheema said, but its analysis of people whose blood oxygen drops during exercise isn't sufficient to support a change in his practice.
For one, the study doesn't discuss the role of pulmonary hypertension, which affects some people with COPD, in blood oxygen levels during exercise, he said.
The study doesn't measure blood oxygen levels during sleep, which is important because many people with COPD have obstructive sleep apnea, he said.
“We'll probably need more studies in the future,” he said.
Wes Venteicher is a Tribune-Review staff writer. Reach him at 412-380-5676 or firstname.lastname@example.org.