Short‐Term Outcomes and Cost Drivers of Emergency Surgery for Acute Abdominal Disease in Super‐Elderly Patients: A Study in the Japanese Tertiary Care Hospital

ABSTRACT Background Although emergency surgery for acute abdominal disease in super‐elderly patients is often associated with high risk and substantial resource utilization, the relationship between short‐term outcomes and inpatient medical costs remains unclear. Methods In total, 247 patients aged ≥ 85 years who underwent emergency surgery for acute abdominal disease were analyzed. Inpatient costs were assessed using total inpatient claim points and the fee‐for‐service component under Japan's diagnosis‐based payment system. Multivariable analyses were performed to identify risk factors for postoperative complications, non‐home discharge, and excess inpatient costs. Results Overall complications occurred in 44.1% of patients, major complications in 19.4%, and 72.1% were discharged home. Mortality was predominantly observed in strangulated bowel obstruction, bowel perforation, and gastrointestinal ischemia or bleeding (8.1%). Multivariable analyses identified American Society of Anesthesiologists physical status (odds ratio OR 3.52, p < 0.001) and operative time (OR 2.10, p < 0.001) as independent risk factors for major complications, while age (OR 1.17, p < 0.001), dementia (OR 2.34, p = 0.006), and major complications (OR 2.87, p = 0.005) were associated with non‐home discharge. Total inpatient claim points were nearly doubled in patients with major complications ( p < 0.001), and residual cost analysis demonstrated disproportionately high inpatient costs among patients without major complications, independent of length of stay. Conclusions Emergency abdominal surgery can be performed with acceptable short‐term outcomes and high likelihood of discharge to home in carefully selected super‐elderly patients. Inpatient costs among patients without major complications might be modifiable through optimization of perioperative management and resource utilization.