Long-acting inhaled medications used by millions of people with chronic obstructive pulmonary disease (COPD) may raise the risk of cardiovascular complications among older patients, a new large Canadian study reveals.
The finding centers around patients over age 65 who are prescribed long-acting bronchodilators - either anticholinergics (such as Spiriva) or beta-agonists (such as Serevent). Both medications are commonly used to relieve the shortness of breath that characterizes moderate to severe COPD and to improve lung function.
The team found that compared with patients who do not use either medication, those using either of these bronchodilators face a notably higher risk for experiencing a cardiac event, such as heart attack or heart failure.
"The bad news is that, although everybody's different, there's a chance that by using these long-acting bronchodilators you may have a mild to moderate risk for cardiovascular problems," said study lead author Dr. Andrea Gershon, a scientist and respirologist in the department of medicine at Sunnybrook Health Sciences Center in Toronto. "The good news is that each of the medications we looked at can also help you if you have COPD."
Benefits and risks
Gershon said she wouldn't recommend a medication if she didn't think that the benefits outweighed the risks. "And I do. But at the same time I feel the choice has to be made on an individual basis," she said. "And there's an obligation to inform our patients that the risk is there, based on the best evidence we have available, which is this study."
The study appears in JAMA Internal Medicine.
More than one-quarter of Americans over the age of 35 have COPD, which is the nation's number one cause of hospitalization due to chronic illness and the third most common cause of death. Emphysema and chronic bronchitis are commonly associated with COPD.
At issue is not the effectiveness of long-acting bronchodilators. Though they do not slow down disease progression, such medications have long been viewed as solid first-line interventions that help improve a patient's overall quality of life. There is no cure for COPD.
Out of concern over drug-related cardiovascular implications, the study team pored through health care database records for more than 191,000 Ontario residents aged 66 and up, all of them COPD patients newly prescribed long-acting bronchodilator medication at some point between 2003 and 2009.
What the study found
The investigators found that during the study time frame, 28% of the patients experienced a cardiovascular "event" that resulted in their being taken to an emergency department and/or being hospitalized.
Both long-acting medications were linked to a higher risk for experiencing events such as a heart attack or heart failure. Neither drug was linked, however, to a boost in the risk for an irregular heart rhythm or stroke. (Use of anticholinergics appeared to offer a measure of protection against ischemic stroke among newly prescribed users, something not found among beta-agonist users.)
In sum, the authors said the findings indicated that all COPD patients using either type of medication need to be closely monitored for signs of related heart trouble.
"The thing is that we tend to treat diseases as if they're each in a silo," said Gershon, "but in reality they all interact with one another. People with COPD have a number of co-morbidities [or co-existing conditions]. And cardiovascular disease is one of the major ones. So questions regarding risk of this kind are very important for this type of patient population."
Dr. Prescott Woodruff, author of an accompanying editorial and a pulmonologist and critical care specialist at University of California, San Francisco Medical Center, suggested that while the fresh findings are "provocative," much of the prior research has indicated the inhalers are safe to use.
"This study suggests that these dilators might have cardiovascular side effects," he acknowledged, "but it doesn't really prove the point. And, meanwhile, there have been some really, really big clinical trials, done under very controlled conditions, which support the safety of these drugs."
It's possible that those studies may have excluded people with heart disease, Woodruff noted. "So perhaps this research is offering a more real-life point of view," he added, but admitted he's skeptical.
Patients should never stop taking a medication without talking to their doctor first, he said. "But it's certainly worth discussing," Woodruff added.
Although the study found an association between the use of long-acting bronchodilators and cardiovascular complications in older patients, it did not prove a cause-and-effect relationship.
For more on COPD, visit the American Thoracic Society.