Acute pain trajectories in elderly patients with fragility hip fractures

Background: Pain management for hospitalized elderly patients with fragility hip fractures (FHF) remains challenging. This study aims to distinguish acute pain trajectories in FHF patients that can inform personalized analgesia management. Methods: We conducted a prospective observational study of patients aged 65 and older with FHF at a Level I trauma center. The primary outcome was daily average pain assessed for five days post-injury using the Brief Pain Inventory (BPI). We used group-based trajectory modeling (GBTM) to distinguish acute pain trajectories. Then, factors and secondary outcomes (opioid use and hospital length of stay [LOS]) associated with more severe pain trajectories were identified. Results: We enrolled 100 consecutive patients with FHF between June 2022 and June 2023. We identified three distinct acute pain trajectories: minimal pain, subsiding pain, and persistent pain. Factors associated with more severe pain trajectories included higher initial pain on admission (OR 1.17, 95 % CI 1.02-1.36, P = 0.047), higher BMI (OR 1.15, 95 % CI 1.02-1.29, P = 0.021), and intertrochanteric fracture type (OR = 6.46, 95 % CI 1.49-27.98, P = 0.013). The persistent pain trajectory was significantly associated with 40 % more opioid use (P = 0.01) and a longer LOS (LOS ratio = 1.45, 95 % CI 1.21-1.74, P < 0.001). Conclusion: Acute pain in FHF patients can be classified into distinct trajectories, providing a basis for personalized pain management. More severe pain trajectories are associated with higher opioid use and longer length of hospital stay.