Osteoporosis Common in COPD and Vitamin D Insufficiency Could be Key

Osteoporosis is common in patients with chronic obstructive pulmonary disease (COPD), Japanese researchers found in a review of the literature.

The review was completed by Daisuke Inoue, MD, of the Division of Endocrinology and Metabolism, Third Department of Medicine, Teikyo University, Chiba Medical Center, in Chiba, Japan and colleagues, and was published in the International Journal of COPD on March 29, 2016.

The researchers found one large study of osteoporosis, GLOW, in which 6.2% of the participants sustained a clinical fracture in the course of 2 years. COPD was found to be one of the most significant comorbidities in those who suffered fractures. Other, similar results were seen in studies from around the world. Although studies involving bone mass density in women with COPD have not shown a conclusive link, the researchers say, “bone biopsy is by far the best way to directly assess bone microarchitecture at the tissue level,” and that connectivity density has been found to be negatively correlated with smoking.

“Mechanisms by which osteoporosis occurs in COPD patients are mostly unknown,” according to the authors. They go on to say that “older age and smoking are common risk factors for osteoporosis and COPD.” Another possibility is that the systemic inflammation that characterizes COPD could be a potential cause of COPD-related osteoporosis, as could pulmonary dysfunction.

The researchers note that “Vitamin D deficiency has been shown to be highly prevalent in COPD.” Vitamin D deficiency results in less calcium absorption and in greater risk of fracture. The studies the researchers reviewed “support a role for vitamin D insufficiency/deficiency in COPD-associated osteoporosis, but its contribution to the fracture risk in COPD patients should be more precisely evaluated in a larger prospective study in the future.”

Regarding the management of COPD-associated osteoporosis, the researchers say, “First of all, clinicians, particularly pulmonologists, should be aware that COPD-associated osteoporosis is extremely undertreated.” They go on to say that patients with COPD over the age of 50 should be screened and evaluated for risk. They add that the lifestyle changes that improve the general condition of COPD patients also lead to increased BMD, although they add, “specific evidence that exercise improves COPD-associated osteoporosis is lacking.”

The researchers conclude with “although we definitely need a specific treatment guideline for COPD-associated osteoporosis, we propose to act immediately to screen every COPD subject for osteoporosis, identify patients at high risk of fracture, and treat them with the standard medications established for primary osteoporosis.”