Risk factors for early postoperative complications after minimally invasive adrenalectomy: a single-centre retrospective cohort study of more than 800 patients

BACKGROUND: Minimally invasive adrenalectomy is associated with low postoperative morbidity, but early complications still occur and may be influenced by patient-related, endocrine, and operative factors. This study aimed to identify the factors associated with 30-day postoperative complications after minimally invasive adrenalectomy. METHODS: This retrospective cohort study included adults undergoing minimally invasive adrenalectomy at a high-volume endocrine surgery referral centre between January 2012 and March 2026. The primary outcome was the occurrence of postoperative complications within 30 days after surgery. Univariable and multivariable logistic regression analyses were performed, with results expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Model discrimination was assessed using the area under the receiver operating characteristic curve (AUC), internal validation used bootstrap resampling, and model fit was evaluated using the Hosmer-Lemeshow test. RESULTS: Among 860 patients who underwent adrenal surgery, 798 (92.8%) were included. Overall, 70 (8.8%) patients developed 30-day postoperative complications. In the multivariable model, hypercortisolism was independently associated with postoperative complications compared with non-functioning lesions (OR 2.413, 95% CI 1.319-4.415; p = 0.004). Compared with ASA score 1, ASA score 3 was independently associated with postoperative complications (OR 1.972, 95% CI 1.074-3.620; p = 0.028), although the overall association for ASA score was borderline. Operative time (OR 1.008, 95% CI 1.003-1.014; p = 0.003), conversion to open surgery (OR 3.171, 95% CI 1.121-8.974; p = 0.030), and multiorgan resection (OR 3.698, 95% CI 1.178-11.609; p = 0.025) were also independently associated with postoperative complications. Surgical approach and laterality were not independent determinants of postoperative morbidity. The final explanatory model showed apparent discrimination, with an AUC of 0.754, decreasing to 0.730 after bootstrap optimism correction. CONCLUSIONS: These findings support a multidimensional interpretation of postoperative morbidity based on patient status, hormonal secretion pattern, and procedural complexity rather than on the minimally invasive approach alone. The model should be interpreted as explanatory and associational rather than as a dedicated preoperative prediction tool.