Combination inhaler might simplify asthma treatment

People suffering from chronic asthma might have a new treatment option that allows them to manage their condition with a single prescribed inhaler that contains two medicines, according to a new review.

Asthma sufferers use maintenance or preventive medication regularly to control their symptoms and improve lung function. Preventive medication is usually a low-dose corticosteroid administered with an inhaler device.

However, when their symptoms deteriorate, they turn to a different "rescue" inhaler containing a short-acting beta2-agonist, to relieve their wheezing and shortness of breath. If not controlled, this type of asthma exacerbation can lead to hospitalization, a visit to an emergency department or treatment with a course of oral steroids.

Researchers have been investigating the use of both a low-dose corticosteroid (budesonide) and beta2-agonist (formoterol) in a single inhaler. The systematic review compares the effectiveness of the new inhaler to the current "best practice" of separate inhalers for different phases of asthma treatment.

The review appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates research in all aspects of health care. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing trials on a topic.

Asthma is one of the leading chronic diseases worldwide and affects about 20 million people in the United States, according to the Centers for Disease Control and Prevention. Asthma is accountable for nearly 2 million visits to U.S. emergency rooms each year. Proper management of the condition with medication might help patients avoid many of these emergency room visits.

"Encouraging people to use their preventive medication is important, as it is often the case that people with asthma default on their inhaled corticosteroids," said lead reviewer Christopher Cates, M.D., at the Community Health Sciences of St. George's at the University of London. "This is partly because inhaled steroids do not make an immediate difference to asthma symptoms."

In most studies, participants had treatment with a single inhaler - one inhalation of 80/4.5 milligrams of budesonide/formoterol twice daily, and as needed. Patients in the control groups used their prescribed inhaled corticosteroid with a separate reliever inhaler. Cates and his colleague evaluated three studies that included more than 4,200 adults and adolescents with chronic asthma. One study also included 224 children.

The Cochrane reviewers found no significant reduction in the number of asthma exacerbations that required hospitalization among the patients who used single inhaler therapy.

However, the reviewers did find that fewer adults on single inhaler therapy had exacerbations needing a course of oral corticosteroids. Compared with 18 people of 100 in the control inhaled corticosteroid group who had an exacerbation treated with oral steroids over 11 months, there were 11 of 100 for the single inhaler therapy group.

"One attraction of the combined inhalers is that the inhaled corticosteroid is automatically taken with the beta-agonist, which does relieve symptoms," said Cates. "Single-inhaler therapy takes this one stage further, as the inhaled corticosteroid is automatically increased, with the beta-agonist, if the asthma symptoms worsen. This approach shows clear advantages in comparison to taking inhaled corticosteroids alone, but is less convincing when compared to current best practice."

Carlos Camargo, M.D., an associate professor of medicine at Harvard Medical School, specializes in asthma and chronic obstructive pulmonary disease, commented that the single-inhaler therapy is an interesting, new approach to chronic asthma treatment.

"The therapy has some support in the literature but requires further study," he said. "If studies confirm that it works, I do anticipate that it will become a popular maintenance therapy for those with moderate-to-severe persistent asthma."

The reviewers wrote that five large studies currently awaiting publication that compare single-inhaler therapy with the current separate inhaler therapy should provide further information about this approach to asthma management.

The Cochrane Collaboration is an international nonprofit, independent organization that produces and disseminates systematic reviews of health care interventions and promotes the search for evidence in the form of clinical trials and other studies of interventions. Visit http://www.cochrane.org for more information.

Cates CJ, Lasserson TJ. Combination formoterol and budesonide as maintenance and reliever therapy versus inhaled steroid maintenance for chronic asthma in adults and children. Cochrane Database of Systematic Reviews 2009, Issue 2.