The mortality burden of frailty in hip fracture patients: a nationwide retrospective study of cause-specific mortality

Maximilian Peter Forssten; Ahmad Mohammad Ismail; Ioannis Ioannidis; Per Wretenberg; Tomas Borg; Yang Cao; Marcelo A F Ribeiro Jr; Shahin Mohseni

doi:10.1007/s00068-022-02204-6

The mortality burden of frailty in hip fracture patients: a nationwide retrospective study of cause-specific mortality

Eur J Trauma Emerg Surg. 2023 Jun;49(3):1467-1475. doi: 10.1007/s00068-022-02204-6. Epub 2022 Dec 26.

Authors

Maximilian Peter Forssten^{1

2}, Ahmad Mohammad Ismail^{1

2}, Ioannis Ioannidis^{1

2}, Per Wretenberg^{1

2}, Tomas Borg^{1

2}, Yang Cao³, Marcelo A F Ribeiro Jr^{4

5}, Shahin Mohseni^{6

7}

Affiliations

¹ Department of Orthopedic Surgery, Orebro University Hospital, 701 85, Orebro, Sweden.
² School of Medical Sciences, Orebro University, 702 81, Orebro, Sweden.
³ Clinical Epidemiology and Biostatistics, School of Medical Sciences, Orebro University, 701 82, Orebro, Sweden.
⁴ Pontifical Catholic University of São Paulo, São Paulo, Brazil.
⁵ Trauma, Burns, Critical Care and Acute Care Surgery, Department of Surgery, Sheikh Shakhbout Medical City-Mayo Clinic, Abu Dhabi, United Arab Emirates.
⁶ Division of Trauma and Emergency Surgery, Department of Surgery, Orebro University Hospital, 701 85, Orebro, Sweden. mohsenishahin@yahoo.com.
⁷ School of Medical Sciences, Orebro University, 702 81, Orebro, Sweden. mohsenishahin@yahoo.com.

Abstract

Purpose: Frailty is a condition characterized by a reduced ability to adapt to external stressors because of a reduced physiologic reserve, which contributes to the high risk of postoperative mortality in hip fracture patients. This study aims to investigate how frailty is associated with the specific causes of mortality in hip fracture patients.

Methods: All adult patients in Sweden who suffered a traumatic hip fracture and underwent surgery between 2008 and 2017 were eligible for inclusion. The Orthopedic Hip Frailty Score (OFS) was used to classify patients as non-frail (OFS 0), pre-frail (OFS 1), and frail (OFS ≥ 2). The association between the degree of frailty and both all-cause and cause-specific mortality was determined using Poisson regression models with robust standard errors and presented using incidence rate ratios (IRRs) with corresponding 95% confidence intervals (CIs), adjusted for potential sources of confounding.

Results: After applying the inclusion and exclusion criteria, 127,305 patients remained for further analysis. 23.9% of patients were non-frail, 27.7% were pre-frail, and 48.3% were frail. Frail patients exhibited a 4 times as high risk of all-cause mortality 30 days [adj. IRR (95% CI): 3.80 (3.36-4.30), p < 0.001] and 90 days postoperatively [adj. IRR (95% CI): 3.88 (3.56-4.23), p < 0.001] as non-frail patients. Of the primary causes of 30-day mortality, frailty was associated with a tripling in the risk of cardiovascular [adj. IRR (95% CI): 3.24 (2.64-3.99), p < 0.001] and respiratory mortality [adj. IRR (95% CI): 2.60 (1.96-3.45), p < 0.001] as well as a five-fold increase in the risk of multiorgan failure [adj. IRR (95% CI): 4.99 (3.95-6.32), p < 0.001].

Conclusion: Frailty is associated with a significantly increased risk of all-cause and cause-specific mortality at 30 and 90 days postoperatively. Across both timepoints, cardiovascular and respiratory events along with multiorgan failure were the most prevalent causes of mortality.

Keywords: Cause-specific mortality; Frailty; Hip fracture; Poisson regression; Postoperative mortality.

MeSH terms

Adult
Aged
Cause of Death
Frail Elderly
Frailty* / epidemiology
Hip Fractures* / surgery
Humans
Retrospective Studies
Risk Factors