Abstract
INTRODUCTION: Time to surgery (TTS) increases mortality risk in old patients with proximal femur fractures (PFFs). Orthogeriatric care pathways reduce mortality and length of stay, but the interaction between TTS and geriatric intervention remains unclear. OBJECTIVE: To identify organisational variables-including geriatric intervention-that are predictive of 90-day mortality and explore their interactions with TTS. MATERIALS AND METHODS: This retrospective study included 7756 PFFs aged over 60 who underwent surgery between 2005 and 2017. Organisational factors influencing 90-day mortality (main outcome) were identified in an administrative database using log-rank tests. Variables such as a mobile geriatric team (MGT) intervening in the emergency department were screened. Selected variables were included in a Cox model alongside TTS and the AtoG score, a validated multidimensional prognostic tool (from 0 no comorbidity to ≥5). Statistical interactions between TTS and organisational variables were calculated. RESULTS: MGT was one of the rare organisational variables with a protective effect: hazard ratio (HR) = 0.81, CI 95% [0.68-0.98], P = 0.03. MGT's strongest effect was for TTS up to 1 day (HR = 0.70, CI95% [0.53-0.92], P = 0.01) and then decreased beyond 2 days (HR = 0.97, CI95% [0.73-1.3], P = 0.08). In patients with an AtoG score ≤ 2, MGT was the strongest parameter: HR = 0.76, CI95% [0.60-0.93], P = 0.03, while the HR for TTS was 1.01 CI 95% [0.99; 1.02], P = 0.15. In patients with an AtoG>2, there was a synergic interaction between MGT and reduced TTS (P = 0.05). CONCLUSION: Geriatric intervention modulated the effect of TTS on 90-day mortality up to a TTS of 2 days. MGT had a positive impact on both vulnerable and earthier patients.