Recently published research reports a possible link between prescriptions of non-steroidal anti-inflammatory drugs (NSAIDs) and increased risk of stress fracture in the US Army active duty population. Stress fractures are common amongst these individuals and also exceedingly costly. By some estimates, approximately $100 million per year is spent by the Department of Defense caring for these injuries. While NSAIDs have a variety of known side-effects, they have also been targeted as possible inhibitors of bone healing through their anti-prostaglandin effects. This study used NSAID prescriptions as a proxy for NSAID use amongst recruits to see if those prescribed more NSAIDs might also have a higher risk of stress fractures.
The team performed a nested case-control study with data from the Total Army Injury and Health Outcomes Database (TAIHOD), which contains a variety of health information on active duty military personnel. They found that prescription for NSAIDs was associated with a 2.9-fold increase in the risk of fracture amongst the whole Army population. When recruits in basic combat training were examined separately, the team found an even stronger association with a 5.3-fold increase. The prescription of acetaminophen was, surprisingly, also associated with an increased risk amongst both the whole Army population and basic combat training group.
The researchers point out that prostaglandins play a central role in signaling mechanical loading in the bone. They surmise that medically suppressing that signal may mute the body’s healing response to mechanical loading, leading to stress fracture over time. The association with acetaminophen was unexpected, but the researchers think this likely indicates that acetaminophen still has some systemic COX inhibitory effects, even if it is generally considered to only act in the brain. Their research may give you reason to pause before prescribing NSAIDs or acetaminophen in military contexts and potentially to active individuals in general.
Full article in Journal of Bone and Mineral Research: Nonsteroidal Anti‐Inflammatory Drug Prescriptions Are Associated With Increased Stress Fracture Diagnosis in the US Army Population