The impact of biological age and age acceleration on 1-year mortality rates in elderly hip fracture patients: a prospective cohort study.

Abstract

This study examines how biological age, calculated from routine lab tests, predicts 1-year mortality in elderly hip fracture patients better than chronological age. Our findings highlight that increased biological aging is linked to higher mortality, emphasizing its potential for improving preoperative risk assessment.

Introduction: Geriatric hip fractures cause high morbidity and up to 30% 1-year mortality. Incorporating biological age and age acceleration into traditional assessments may improve predictions of outcomes and guide clinical interventions and perioperative counseling.

Methods: In this prospective study, patients aged ≥ 50 with low-energy hip fractures had demographic data, chronological age, comorbidities, and nine laboratory parameters collected preoperatively. Biological age was computed per Levine et al. (2018), and age acceleration was defined as the difference between biological and chronological age. Patients were categorized by age acceleration (< 20 vs. ≥ 20 years) and into four subgroups (-15 to 5, 5-20, 20-30, and ≥ 30 years) for survival analysis.

Results: Ninety-one patients were included. Mean chronological age was 76.6 (SD 9.2) years, biological age 90.5 (SD 15.0) years, and age acceleration 13.9 (SD 13.1) years; the mean Charlson Comorbidity Index was 4.1 (SD 3.1). One-year mortality was 25.3%. Those who died had higher CCI (6.0 vs. 3.5; p = 0.001), biological age (102.6 vs. 86.4; p < 0.001), and age acceleration (23.8 vs. 10.7; p < 0.001). Mortality increased from 7.7% in the lowest (-15 to 5 years) to 63.6% in the highest (≥ 30 years) age acceleration bracket. Cox regression-adjusted for ambulation, race, sex, CCI, and smoking-confirmed age acceleration ≥ 20 years as an independent predictor (HR 3.27; 95% CI 1.28-8.38; p = 0.014).

Conclusion: Biological age and age acceleration outperform chronological age in predicting 1-year mortality, supporting their role in risk stratification for geriatric hip fracture patients.