A new study from Columbia University’s Mailman School of Public Health has shed light on a previously unknown correlation between air pollution and bone density in postmenopausal women. The study has found that exposure to elevated levels of air pollutants, particularly nitrogen oxides, is associated with bone damage in these women. It was the first to explore the effects of air pollution mixtures on bone outcomes and the first to connect air pollution and bone mineral density in postmenopausal women.
Data Population: The study analyzed data from an ethnically diverse population of over 161,000 postmenopausal women in a long-running U.S. women's health study, using participants' home addresses to estimate levels of exposure to pollutants, including PM10 (small air pollution particles), nitrogen monoxide, nitrogen dioxide, and sulfur dioxide.
Bone density was measured at enrollment in the study and after one, three, and six years using dual-energy X-ray absorptiometry (DEXA) scans, which included whole-body, total hip, femoral neck, and lumbar spine scans.
Results: The results of the study showed that high levels of nitrogen oxides in the air nearly doubled the effects of normal aging on bone density in the spine. Specifically, the study found that nitrogen oxides caused a 1.22% annual loss of bone density in the lumbar spine, nearly double the annual effect of aging on any of the anatomical sites evaluated. The researchers suspect that the effects occur through bone cell death by way of oxidative damage and other mechanisms.
More Research is Needed!.. While the study only found an association between pollution levels and bone density, and not a cause-and-effect link, the researchers urge further efforts to detect those at higher risk of air pollution-related bone damage. This is due to the high cost burden associated with osteoporosis-related fractures.
Findings!.. According to the study, about 2.1 million osteoporosis-related bone fractures occur each year, resulting in up to $20.3 billion in annual direct health costs. About 80% of the 10 million Americans with osteoporosis are women, and women who have gone through menopause are at higher risk, with about 1 in 2 women over 50 experiencing a bone fracture because of osteoporosis.
Lead author Dr. Andrea Baccarelli, chair of environmental health sciences at Columbia University, notes that "improvements in air pollution exposure, particularly nitrogen oxides, will reduce bone damage in postmenopausal women, prevent bone fractures, and reduce the health cost burden associated with osteoporosis among postmenopausal women."
Alert, Poor Air Quality is a Risk!.. The study's first author, Dr. Diddier Prada, an associate research scientist at the Mailman School, adds that "our findings confirm that poor air quality may be a risk factor for bone loss. For the first time, we have evidence that nitrogen oxides, in particular, are a major contributor to bone damage and that the lumbar spine is one of the most susceptible sites of this damage."
In conclusion, this groundbreaking study from Columbia University has identified a previously unknown link between air pollution and bone density in postmenopausal women. While the study only found an association between pollution levels and bone density, and not a cause-and-effect link, it highlights the need for further efforts to detect those at higher risk of air pollution-related bone damage.
The study's findings also underscore the importance of improving air quality, particularly with regard to nitrogen oxides, in order to reduce the risk of bone damage and related health costs among postmenopausal women.
