Association of bone mineral density with lung function in a Chinese general population: the Xinxiang rural cohort study

Background: Bone mineral density (BMD) has been positively associated with lung function in patients diagnosed with respiratory diseases such as chronic obstructive pulmonary disease (COPD) and cystic fibrosis. However, the relationship between BMD and lung function is inconsistent in the general population. Methods: To investigate the association between BMD and lung function in a Chinese general population, a total of 1024 adults aged 40-70 years old from Qiliying (an industrial polluted exposure area) and Langgongmiao (the reference area with non-industrial pollution) were recruited and underwent BMD and spirometry tests. Results: Both BMD and lung function levels were lower in the exposed area compared to the reference area. In addition, BMD and lung function levels were also lower in females compared to males. Both Spearman and partial correlation analyses showed that BMD was positively correlated with FVC and FEV1. After adjusting linear regression analyses for potential confounding factors, every 0.1 g/cm(2) drop in BMD was associated with 53.0 mL decrease in FVC and 33.5 mL decrease in FEV1. Conclusions: A reduction of BMD is associated with lower lung function in a general population from China.