Is FEV₁ an indicator of low bone mineral density in adults? The Fifth Korea National Health and Nutrition Examination Survey

The association between forced expiratory volume in 1 s (FEV₁) and bone mineral density (BMD) is heterogeneous in population-based studies. This study aimed to investigate this relationship when sex and menopausal status in women, BMD sites, and anthropometric measures were taken into account. In 3,975 Koreans (1,783 men, 662 premenopausal women, 1,530 postmenopausal women, aged 40–91 years) participating in the Fifth Korea National Health and Nutrition Examination Survey in 2010–2011, this relationship for BMD at femur (total and neck) and lumbar spine was examined in each subgroup after adjusting for age, smoking, and alcohol habit, physical activity, calcium intake, osteoporosis treatment, and anthropometry (weight and height, height and BMI, or height, lean mass, and fat mass). Airflow limitation (FEV₁ ≥ 80, 50–80, and < 50 % of predicted FEV₁) and lower vs. higher BMD using BMD values at site and subgroup-specific 10 percentile of BMD distribution were defined. In multiple regression analysis, the association between FEV₁ and BMD was significant in premenopausal women [B = 0.027–0.031 (total femur), 0.035–0.037 (femoral neck), p < 0.05] but not in other subgroups. In logistic regression analysis, severe airflow limitation was associated with lower BMD in postmenopausal women [OR 2.21–2.37 (total femur), 2.25 (femoral neck), p < 0.05] and premenopausal women (OR 2.14, 95 % CI, 1.01–4.50 for femoral neck in height and body composition-adjusted model), but not exhibit these associations in men. As a whole, the associations with spine BMD were non-significant. Therefore, the associations were sex-, menopausal status in women-, and BMD site-specific, while the types of anthropometry had similar effects on the associations.