Oral corticosteroids are considered the most effective medication for treating asthma; however, certain side effects have been reported during the prolonged use of this treatment method, including muscle weakness, lowered resistance to infection, and osteoporosis. A study conducted at the Seoul National University Medical Research Center in South Korea has revealed that asthma patients who have never been prescribed these drugs still run the risk of suffering a loss of bone density.

"We know prolonged use of corticosteroids in the treatment of asthma is a risk factor of osteoporosis, but we haven't had definite data showing the relationship between asthma itself and bone loss," one of the study’s lead authors, Dr. Jae-Woo Jung said in a statement. "This study has shown a meaningful association between the two conditions even in the absence of previous oral corticosteroid use."

Jung and his colleagues from the university recruited 7,034 patients who underwent bone mineral density (BMD) tests and methacholine bronchial challenge tests to participate in the study. After excluding participants who were prescribed corticosteroids, the research team identified 433 patients who reported a medical diagnosis of asthma or airway hyperresponsiveness (AHR). Compared to patients with no signs of a respiratory condition, patients with asthma or AHR were more likely to suffer from low lumber spine and femur bone density.

"It is difficult to pinpoint the cause of bone loss in this subset of patients," allergist Dr. John Oppenheimer said. "Reasons can include corticosteroid use, low levels of vitamin D or even race. This research has unveiled findings that need be further studied."

According to the American Academy of Allery, Asthma & Immunology, there are currently 26 million people in the United States suffering from asthma. While oral corticosteroids are the preferred treatment among allergists, adverse side effects have been reported, most notably osteoporosis. In hopes of avoiding bone density loss, many allergists and asthma experts will often prescribe the lowest dose of oral corticosteroids or opt for an inhalable form of the medication.

"Asthma is a serious disease that can be life-threatening," Dr. Oppenheimer added. "It is important that those with asthma and other breathing problems continue their prescribed treatment. It is also imperative that allergists discuss the potential of the disease itself or as a consequence of therapy in asthma sufferers."

Source: Kim J, Kang H, Jung J, et al. Are asthmatic patients prone to bone loss? Annals of Allergy, Asthma & Immunology. 2014