Relationship between pulmonary function and bone mineral density in the Korean National Health and Nutrition Examination Survey (KNHANES)

Abstract

Background: Osteoporosis is common in chronic obstructive pulmonary disease (COPD) patients. The relationship between osteoporosis and COPD has been primarily reported in patients with moderate to severe COPD, but there is no report in the general population. The aim of this study is to investigate the relationship between bone mineral density (BMD) and lung function in the general Korean population. Methods: This study was based on data acquired from the Fourth and Fifth Korea National Health and Nutrition Examination Surveys (KNHANES IV and V), conducted from 2008 to 2010. The study population included 4,501 subjects (aged ≥50 years) who underwent both spirometry and BMD. The study populations were divided into two groups by sex to correct for the effects of gender on BMD. Results: The participants included 2100 (46.7%) males and 2401 (53.3%) females. All female participants were postmenopausal women. For both genders, the BMD of the femur neck, total femur, and L-spine correlated significantly with age, body mass index (BMI), fat free mass index (FFMI), body fat percentage, smoking amount, parathyroid hormone levels(PTH), daily calcium and phosphorus intake, alkaline phosphatase levels (ALP), and FEV1/FVC by simple linear analysis. After adjusting for age, BMI, FFMI, body fat percentage, smoking amount, serum 25(OH) levels, daily calcium and phosphorus intake, ALP, BMD of the femur neck, total femur, and Lumbar spine in both males and females were reduced significantly as age, and ALP levels increased. There were no correlations between BMD and severity of airway obstruction. Conclusion: In the general population, diminution of BMD does not lower pulmonary function. Further work including other factors is needed to determine the possible role of BMD in pulmonary function.