Is lung function associated with bone mineral density? Results from the Hertfordshire Cohort Study

Abstract

Given limited information available regarding associations between lung function and bone mineral density among healthy subjects, we undertook these analyses in the Hertfordshire Cohort Study. Forced expiratory volume in 1s (FEV(1)), forced vital capacity (FVC) and FEV(1)/FVC were not associated with bone mineral density at any site; associations with bone mineral content were removed by adjustment for body size. There is limited information available regarding the association between lung function and bone mineral density among healthy elderly subjects. We addressed this issue in the Hertfordshire Cohort Study. From the above cohort, 985 subjects (496 men and 489 women) aged 60-72years were recruited. All subjects underwent bone density measurements using dual energy X-ray absorptiometry and lung function tests using standardised spirometry. Chronic obstructive pulmonary disease (COPD) was defined as a FEV(1)/FVC ratio <lower limit of normal, calculated using separate equations for men and women. Measures of lung function (FEV(1), FVC and FEV(1)/FVC) were not associated with bone mineral density at the lumbar spine, femoral neck and total hip in men or women; associations with bone mineral content and bone area were removed by adjustment for body size and lifestyle confounders. In this cohort, there were no associations observed between COPD and any measure of bone mass. There was no association between lung function and bone mass in this community dwelling cohort after adjustment for body size and other confounders.