HALP score at hospital admission is associated with 90-day surgical site infection following geriatric hip fracture surgery: a retrospective cohort study

Background Surgical site infection (SSI) remains one of the most challenging complications following geriatric hip fracture surgery, making early identification of high-risk patients important for perioperative management. Systemic inflammatory and immunonutritional biomarkers derived from routine laboratory parameters have shown prognostic value across various clinical settings; however, their role in SSI after geriatric hip fracture surgery remains unclear. This study aimed to evaluate the potential value of the hemoglobin–albumin–lymphocyte–platelet (HALP) score and widely studied laboratory-based biomarkers for 90-day SSI following geriatric hip fracture surgery. Methods This retrospective, single-center cohort study included patients aged ≥ 60 years who underwent surgical treatment for femoral neck, intertrochanteric, or subtrochanteric fractures between January 2014 and April 2026. Biomarkers were calculated from the first blood sample obtained at hospital admission before any therapeutic intervention. The primary outcome was SSI within 90 days after surgery. Between-group comparisons were performed using the Mann–Whitney U and chi-square tests. Discriminative performance was assessed using ROC curve analysis, and independent associations with SSI were evaluated using multivariable logistic regression. Results A total of 2,229 patients were included. HALP, PNI, CALLY, LMR, and MPV/PLT values were significantly lower, whereas NLR, PLR, SII, SIRI, AISI, and CAR values were significantly higher in patients who developed 90-day SSI (all P < .001). HALP showed the highest observed AUC for 90-day SSI (AUC = 0.891, 95% CI: 0.874–0.908), followed by PLR (AUC = 0.876, 95% CI: 0.852–0.900). In multivariable logistic regression analysis, HALP was independently associated with 90-day SSI (adjusted OR = 0.796, 95% CI: 0.758–0.836; P < .001). Conclusions HALP was independently associated with 90-day SSI following geriatric hip fracture surgery and showed the highest observed AUC among the evaluated biomarkers. These findings support the potential value of HALP as a readily available biomarker for preoperative SSI risk assessment. Clinical trial number Not applicable.