Association between exposure to fine particulate matter and osteoporosis: a population-based cohort study

SUMMARY: Long-term environmental air pollution exposure was associated with osteoporosis’ risk in a cohort of women at high risk of fracture. Cortical sites seemed to be more susceptible to the exposure’s effect. INTRODUCTION: Environmental air pollution has been associated with disruption of bone health at a molecular level. Particulate matter (PM) exposure can simultaneously stimulate bone resorption and halt bone formation. The primary aim of the present study is to describe the association between long-term exposure to PM and osteoporosis in a large cohort of women at high risk of fracture. METHODS: Clinical, demographic, and densitometric data were extracted from the DeFRAcalc79 dataset, which gathers data on women at risk for osteoporosis. Data on the monitoring of PM10 and PM2.5 concentrations were retrieved from the Italian institute of environment protection and research (Istituto Superiore per la Protezione e la Ricerca Ambientale, ISPRA). Generalized linear models with robust estimators were employed to determine the relationship between BMD and PM long-term exposure. RESULTS: A total 59,950 women from 110 Italian provinces were included in the study. PM 2.5 exposure was negatively associated with T-score levels at the femoral neck (β −0.005, 95 CI −0.007 to −0.003) and lumbar spine (β −0.003, 95% CI −0.006 to −0.001). Chronic exposure to PM2.5 above 25 μg/m(3) was associated with a 16% higher risk of having osteoporotic T-score at any site (aOR 1.161, 95% CI 1.105 to 1.220), and exposure to PM10 above 30 μg/m(3) was associated with a 15% higher risk of having osteoporotic T-score at any site (aOR 1.148, 95% CI 1.098 to 1.200). CONCLUSION: Long-term exposure to air pollution was associated with higher risk of osteoporosis. Femoral neck site seemed to be more susceptible to the detrimental effect of PM exposure than lumbar spine site. KEY MESSAGE: Exposure to air pollution is associated with osteoporosis, mainly at femoral site.