BackgroundThis study aimed to investigate the incidence and risk factors of postoperative urinary retention (POUR) among elderly patients who underwent hip fracture surgery and to evaluate the effect of indwelling catheterization on the occurrence of POUR.Materials and methodsFrom January 2012 to January 2015, consecutive patients aged over 70 years who underwent hip fracture surgery were enrolled in this study. All patients underwent indwelling catheterization due to voiding difficulty upon admission. Demographic data, perioperative variables, and postoperative duration of patient-controlled analgesia and indwelling catheterization, postoperative complications, and mortality were collected. The incidence of POUR was investigated, and the risk factors related to POUR were analyzed using a logistic regression analysis. The cutoff value for the timing of catheter removal was determined using receiver operating characteristic (ROC) curve analysis.ResultsPOUR developed in 68 patients (31.8%) of the 214 patients. Of these, 24 (35.3%) were male. The indwelling catheter was left in place for an average of 3.4 days (range, 0–7 days) postoperatively. A significant difference was noted in gender and duration of indwelling catheterization between patients with POUR and without. The cutoff value for the timing of catheter removal as determined by ROC curve analysis was 3.5 postoperative day with 51.4% sensitivity and 71.5% specificity. Multiple logistic regression revealed that the duration of the indwelling catheter [odds ratios (OR), 0.31; p = 0.016)] and male gender (OR, 2.22; p = 0.014) were independent risk factors related to the occurrence of POUR.ConclusionsThe significant risk factors of POUR among elderly patients undergoing hip fracture surgery were early indwelling catheter removal and male gender. Therefore, early removal of indwelling catheter in elderly patients following hip fracture surgery may increase the risk of POUR, especially in male patients.