Impact of obesity on peri-operative outcomes at robotic-assisted, laparoscopic and open partial nephrectomy using national inpatient sample data.

Obesity is becoming increasingly common around the world and is often co-occurring with chronic diseases that could complicate surgical treatment. Partial Nephrectomy is a complex surgical procedure and obesity may influence surgical complexity, postoperative recovery and resource use. Previous studies have produced mixed results, and many are limited by small sample sizes or single-center data. This study assesses how obesity affects in-hospital perioperative outcomes by analyzing data from a large national dataset. We performed a retrospective analysis of the National Inpatient Sample from 2018 to 2020, including adult patients with non-metastatic RCC who underwent open, laparoscopic, or robot assisted partial nephrectomy. Outcomes included in-hospital mortality, complications, discharge disposition, length of stay, and total hospital charges. Survey-weighted methods and multivariable regression models were employed to adjust for measured demographic, clinical, and hospital-level factors. Among 40,300 weighted hospitalizations, 10,270 patients were obese, younger and had higher comorbidity burdens. Surgical approaches were similar across groups, with robotic partial nephrectomy most frequent. Unadjusted analyses showed higher postoperative complication rates in obese patients. However, after adjusted analysis, obesity was not independently linked to in-hospital mortality, major complications, non-home discharge, length of stay, or hospital costs. Robotic surgery was associated with lowest adjusted odds of complications, mortality, and shorter hospitalization. The comorbidity index proved a reliable predictor for mortality, complications, length of stay, and total charges. Obesity alone was not an independent predictor of adverse in-hospital perioperative outcomes following partial nephrectomy. It is of utmost importance to manage the underlying conditions, as the comorbidity index remains the strongest determinant of worse outcomes and higher hospital costs. The robotic partial nephrectomy was associated with lowest adjusted odds of complications and shorter hospitalization within contemporary practice patterns.