Assessing the Correlation between Serum Albumin and Serum Total Cholesterol Levels as Predictors of Surgical Site Infection in Abdominal Surgery Patients - Prospective Observational Study

Background: Surgical-site infection (SSI) remains a common complication of abdominal surgeries. Because hypo-albuminaemia and hypo-cholesterolaemia each reflect impaired nutritional inflammatory reserve, we prospectively examined whether their pre-operative levels alone or combined predict 30-day SSI. Methods: In a single-centre prospective observational cohort (January 2025 – June 2025), 150 consecutive adults scheduled for elective or emergency abdominal surgery had fasting serum albumin and total cholesterol measured ≤ 24 h before incision. Standard peri-operative care followed international SSI-prevention guidelines. Patients were surveilled to POD 30 using Centers for Disease Control criteria; 135 completed follow-ups. Multivariable logistic regression adjusted for diabetes, wound class, and operative time; predictive performance was assessed by area under the receiver-operator-characteristic curve (AUC) and calibration statistics. Results: SSI occurred in 24 of 135 patients (incidence = 17.8 %). Mean albumin and cholesterol were significantly lower in infected than non-infected patients (3.2 ± 0.4 g dL⁻¹ vs 3.7 ± 0.4 g dL⁻¹, and 158 ± 28 mg dL⁻¹ vs 182 ± 31 mg dL⁻¹; both p < 0.001). After adjustment, each 0.5 g dL⁻¹ increase in albumin reduced SSI odds by 40 % (adjusted OR 0.60, 95 % CI 0.42–0.87) and each 10 mg dL⁻¹ rise in cholesterol by 11 % (aOR 0.89, 95 % CI 0.82–0.97). A composite albumin-plus-cholesterol score achieved an AUC of 0.81 (95 % CI 0.71–0.90), outperforming albumin alone (AUC 0.72) and the National Nosocomial Infection Surveillance index (AUC 0.68), with good calibration (Hosmer–Lemeshow P = 0.62) and an 18 % net reclassification improvement. Conclusion: Low pre-operative serum albumin and total cholesterol are independent, synergistic predictors of SSI after abdominal surgery. Their routine, low-cost measurement enables pragmatic risk stratification, allowing focused deployment of intensified SSI-prevention bundles to the one-fifth of patients at highest risk.