Peripheral Artery Disease and Long-Term Risk of Femur Fracture Among Older Adults: The Atherosclerosis Risk in Communities Study

Introduction: Femur fracture can have devastating consequences in older patients. Lower extremity peripheral artery disease (PAD) reduces physical function, which can in turn increase the risk of falls. However, less is known regarding the association of PAD with incident femur fracture in older adults. Hypothesis: PAD is associated with a higher risk of incident femur fracture independent of potential confounders. Methods: We included 5,276 participants from ARIC Visit 5 (2011-2013) (mean age 76 [standard deviation: 5] years, 57% women and 22% self-identified Black race). Femur fractures were defined as an outpatient encounter or hospitalization with ICD-9 codes: 820-821 or ICD-10 codes: S72. We quantified the association of PAD status at baseline, based on ankle-brachial index (ABI) ≤0.9 or clinical history of PAD, with incident femur fracture using multivariable Cox regression and follow-up until 2019. Results: There were 224 incident femur fractures over a median follow-up of 7.2 [IQI 5.6-7.8] years. The incidence rate of femur fracture was almost 2-times higher in participants with PAD compared to those without a history of PAD and ABI 1.11-1.20 (reference group) (10.5 [7.5-14.8] vs. 5.5 [4.3-6.9] per 1,000 person-years). This association persisted after accounting for demographic (hazards ratio [HR]: 1.86 [95% CI 1.23-2.84] in Model 1) and other confounders (HR 1.59 [1.04-2.46] in Model 2) (Table). When we excluded participants with a clinical history of PAD, low ABI (≤0.9) remained significantly associated with incident femur fracture compared to the reference group (HR 1.94 [1.18-3.19]). Our findings were consistent in demographic and clinical subgroups (e.g., by sex and diabetes status). Conclusions: In community-dwelling older adults, PAD, even when not clinically diagnosed, was associated with an increased risk of femur fracture. Clinicians and patients should be aware of this complication of PAD and consider preventive measures to avoid falls (e.g., exercise counseling, and making home safer).