The neutrophil-to-lymphocyte ratio (NLR) after surgery for hip fracture (HF)

Background The NLR is a prognostic factor for outcome and survival in cardiology, oncology and digestive surgery. NLR has not yet been studied in HF. Methods Retrospective analysis of a prospective cohort of 247 consecutive patients, older than 65 years, operated for HF. Mortality at 12 months was registered, as the perioperative NLR values. Results After hip surgery in the 247 patients (women 71%, median age 85 years, range: 66–102), the mortality was 27.2% [95%confidence interval (CI): 21.4–33.0] at 12 months. Univariate analysis detected four risk factors for mortality: age (Hazard Ratio (HR) – by 10 year-increments: 2.08 [95%CI: 1.37–3.17], P < 0.001), male gender (HR: 1.92 [95%CI: 1.17–3.14], P = 0.009, MCM (≥3) (HR: 1.71 [95%CI: 1.006–2.92], P = 0.047 and NLR > 5 at day 5 (HR: 1.8 [95%CI: 1.11–2.94], P = 0.002). In multivariate analysis, two factors remained significantly associated with mortality: age (HR: 2.28 [95%CI: 1.49–3.47], P < 0.001) and male gender (HR: 2.26 [95%CI: 1.38–3.72], P = 0.001). Two independent risk factors of postoperative cardiovascular complications were identified: NLR > 5 at day 5 (Odds Ratio (OR): 3.34 [95%CI: 2.33–4.80], P = 0.001) and MCM (OR: 3.04 [95%CI: 2.16–4.29], P = 0.006). A higher risk of infection was independently associated with a NLR > 5 at day 5 (OR: 2.12 [95%CI: 1.44–3.11], P = 0.02). Conclusions The NLR at fifth postoperative day is a risk factor of postoperative mortality and cardiovascular complications.