¹Quinn R, ¹LaFleur A, ¹Baker C, ²Mahmud K, ¹Calvert J, ¹Sherman C
¹Riverside University Health System Medical Center, Moreno Valley, CA, United states; ²University of California – Riverside, Riverside, CA, United states

Introduction
Hip fractures have been considered an independent risk factor for developing dementia. However, whether patients with osteoporosis are at an elevated risk of developing dementia following a hip fracture remains to be studied. The aim of this study was to evaluate if patients with osteoporosis are at an increased risk of developing dementia within 5 years of a femoral neck fracture.

Methods
A retrospective cohort study was performed using the TriNetX database. Cohorts were defined using Common Procedural Terminology and International Classification of Diseases-10 codes. Inclusion criteria included patients over the age of 60 with osteoporosis who received a total hip arthroplasty or hemiarthroplasty of the hip. Exclusion criteria included the diagnosis of dementia prior to hip arthroplasty or a history of fragility fractures, including vertebral compression, proximal humerus, distal radius/ulna, intertrochanteric, and subtrochanteric fractures. Patients were divided into two groups (elective group and fracture group) based on whether they had a femoral neck fracture. The cohorts were propensity score–matched based on demographics and risk factors for dementia. The primary outcome was the development of dementia within 5 years of hip arthroplasty. Risk analysis and Kaplan-Meier survival analysis were performed.

Results
After balancing the cohorts, 2,652 patients were included in each group. There were no significant differences in age, sex, race/ethnicity, neurocognitive disorders, diabetes, thyroid disorders, hypertension, hyperlipidemia, ischemic heart disease, nicotine dependence, vitamin D use, bisphosphonate use, or teriparatide use. Within 5 years of hip arthroplasty, 141 patients in the elective group and 228 patients in the fracture group developed dementia with a risk ratio of 1.617 (95% CI: 1.320, 1.981).

Conclusion
In patients with osteoporosis, a femoral neck fracture significantly increases the chances of developing dementia. Prospective longitudinal cohort studies are needed to further investigate the link between fragility fractures in patients with osteoporosis and the risk of developing dementia.