Prognostic value of the preoperative HALP score for 30-day and 1-year mortality in older adults undergoing hemiarthroplasty for intracapsular hip fracture: a retrospective cohort study

Hip fracture mortality in older adults reflects biological reserve as well as the acute injury. The hemoglobin, albumin, lymphocyte, and platelet (HALP) score integrates anemia, nutritional status, immune competence, and systemic inflammatory burden. We evaluated whether preoperative HALP was associated with mortality after hemiarthroplasty for intracapsular hip fracture. This single-center retrospective cohort included 906 consecutive patients aged > 60 years who underwent hemiarthroplasty between 1 January 2013 and 1 January 2024. One-year all-cause mortality was the primary outcome and 30-day mortality the secondary outcome. Admission blood samples were obtained before intravenous fluid administration. HALP was log2-transformed because the untransformed score did not satisfy linearity in the logit. Logistic regression adjusted for age and sex; hemoglobin-to-red cell distribution width ratio (HRR) and eosinophil-to-lymphocyte ratio (ELR) were evaluated in an expanded comparison model. Discrimination, calibration, multicollinearity, Kaplan-Meier survival, and Cox regression were also assessed. Thirty-day mortality was 14.3% (130/906) and 1-year mortality was 38.9% (352/906). Median HALP was lower among patients who died within 1 year [15.48, interquartile range (IQR) 10.51–22.93] than among 1-year survivors [19.46 (13.22–29.27); p < 0.001]. In the primary adjusted model, each doubling of HALP was associated with lower odds of 1-year mortality [odds ratio (OR) 0.70, 95% confidence interval (CI) 0.59–0.82; p < 0.001], but not 30-day mortality (OR 0.87, 95% CI 0.70–1.08; p = 0.214). The 1-year model had an area under the receiver operating characteristic curve (AUC) of 0.664 (95% CI 0.627–0.698) and Hosmer-Lemeshow p = 0.440. HALP alone showed modest 1-year discrimination (AUC 0.603, 95% CI 0.565–0.640). In supportive survival analysis, each doubling of HALP was associated with lower mortality hazard [hazard ratio (HR) 0.74, 95% CI 0.67–0.82; p < 0.001]. Lower preoperative HALP was associated with higher 1-year mortality after adjustment for age and sex, whereas no independent association was demonstrated for 30-day mortality. HALP may reflect overall physiological reserve, but its modest stand-alone discrimination does not support use as an isolated clinical risk tool. Prospective studies incorporating frailty, comorbidity, nutritional, cognitive, and functional measures are required.