Association between admission albumin levels and 30-day readmission after hip fracture surgery in geriatric patients: a propensity score-matched study

Purpose This study aimed to evaluate the correlation admission albumin levels and 30-day readmission after hip fracture surgery in geriatric patients. Methods In this retrospective cohort study, 1270 geriatric patients admitted for hip fractures to a level I trauma center were included. Patients were stratified by clinical thresholds and albumin level quartiles. The association between admission albumin levels and 30-day readmission risk was assessed using multivariate logistic regression and propensity score-matched analyses. The predictive accuracy of albumin levels for readmission was evaluated by ROC curves. The dose-response relationship between albumin levels and readmission risk was examined. Results The incidence of 30-day readmission was significantly higher among hypoalbuminemia patients than those with normal albumin levels (OR = 2.090, 95%CI:1.296-3.370, p = 0.003). Furthermore, propensity score-matched analyses demonstrated that patients in the Q2(35.0-37.9 g/L) (OR 0.621, 95%CI 0.370-1.041, p = 0.070), Q3(38.0-40.9 g/L) (OR 0.378, 95%CI 0.199-0.717, p < 0.001) and Q4 (>= 41 g/L) (OR 0.465, 95%CI 0.211-0.859, p = 0.047) quartiles had a significantly lower risk of 30-day readmission compared to those in the Q1(< 35 g/L) quartile. These associations remained significant after propensity score matching (PSM) and subgroup analyses. Dose-response relationships between albumin levels and 30-day readmission were observed. Conclusions Lower admission albumin levels were independently associated with higher 30-day readmission rates in elderly hip fracture patients. Our findings indicate that serum albumin may assist perioperative risk assessment, and prompt correction of hypoalbuminemia and malnutrition could reduce short-term readmissions after hip fracture surgery in this high-risk population.