Does Inflammation Increase Fracture Risk?

By Salynn BoylesReviewed by Vrunda Bhavsar Desai, MD, FACOG, Assistant Professor of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CTAging is associated with chronic, low-grade, systemic inflammation characterized by an increase in circulating levels of inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and interleukin 1 (IL-1).This pro-inflammatory response has been linked to a wide range of chronic conditions associated with aging, including cardiovascular disease,1 diabetes,2 and dementia.3 There’s mounting evidence implicating chronic systemic inflammation in osteoporosis and fracture risk in adults.

Most studies in older white womenAt least 10 observational studies have examined the association of inflammatory markers with bone loss and fracture risk in humans. Most included only older women, and most of these subjects were white, says Centers for Disease Control and Prevention epidemiologist and researcher Kamil Barbour, PhD, MPH, who led 3 of the studies examining inflammation and osteoporosis-related fractures while at the University of Pittsburgh. But despite this limitation, he says, the studies offer compelling evidence that inflammation could be a significant risk factor for bone loss and fracture in aging.The trials conducted by the University of Pittsburgh research team showed a 1.5-fold to 2.5-fold greater risk for fracture in older women with the highest levels of inflammation compared to those with the lowest levels.“Two of our studies looked at hip fractures and 1 examined nontraumatic fractures, and we did find very strong associations,” Dr. Barbour said. “In 2 of the 3 studies there was a 2.5-fold greater risk for hip fractures in women with high levels of inflammation.”

More study neededWhile the majority of the studies suggest a causal role for inflammation in age-related bone loss and fracture risk, Dr. Barbour says more research is needed to strengthen the association, especially in men.“I know a lot of people will remain skeptical and say inflammation is just a marker for frailty or something else,” he says. “But in our studies we controlled for frailty, and this did not change our results.”Published: 06/03/2014

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