What Accounts for Rib Fractures in Older Adults?

Lisa-Ann Wuermser,Sara J Achenbach,Sundeep Khosla,Shreyasee Amin,L Joseph Melton

doi:10.4061/2011/457591

Abstract

To address the epidemiology of rib fractures, an age- and sex-stratified random sample of 699 Rochester, Minnesota, adults age 21–93 years was followed in a long-term prospective study. Bone mineral density (BMD) was assessed at baseline, and fractures were ascertained by periodic interview and medical record review. During 8560 person-years of followup (median, 13.9 years), 56 subjects experienced 67 rib fracture episodes. Risk factors for falling predicted rib fractures as well as BMD, but both were strongly age-related. After age-adjustment, BMD was associated with rib fractures in women but not men. Importantly, rib fractures attributed to severe trauma were associated with BMD in older individuals of both sexes. Self-reported heavy alcohol use doubled fracture risk but did not achieve significance due to limited statistical power. Bone density, along with heavy alcohol use and other risk factors for falling, contributes to the risk of rib fractures, but no one factor predominates. Older women with rib fractures, regardless of cause, should be considered for an osteoporosis evaluation, and strategies to prevent falling should be considered in both sexes.

Highlights

Fractures occur when loads on the skeleton exceed the breaking strength of bone
Most fractures in older individuals of both sexes are related to impaired bone strength, as assessed clinically by bone densitometry [4], and an association between areal bone mineral density (BMD) and rib fracture risk was documented in the Osteoporotic Fractures in Men (MrOS) cohort that was independent of other risk factors [2]
Associations of rib fractures with low bone density have been observed among older women [5, 6], who account for the majority of all fractures in the population, but other potential risk factors have not been addressed in that group

Summary

Introduction

Fractures occur when loads on the skeleton exceed the breaking strength of bone. Among young adults, the skeletal loads causing rib fractures are generally due to high-energy traumatic events. Associations of rib fractures with low bone density have been observed among older women [5, 6], who account for the majority of all fractures in the population, but other potential risk factors have not been addressed in that group This is an important limitation as interventions for bone loss and for other determinants of fracture risk (e.g., falls) would likely differ. Since rib fractures are associated with significant morbidity, mortality, and cost [7,8,9], as well as an increased risk of subsequent fractures of other types [2, 10], it is important to evaluate the relative impact of bone density versus other contributors to rib fracture risk We address this issue in an analysis of prospective data from a cohort of women and men randomly sampled from the community

Methods

Results

Discussion

Conclusion