Forecasting outcomes after cholecystectomy in octogenarian patients

Background: Although gallstone disease increases with aging, elderly patients are less likely to undergo cholecystectomy. This is because age itself is a negative predictor after cholecystectomy. The ACS-NSQIP risk calculator can therefore help surgeons decide whether to operate or not. However, little is known about the accuracy of this model outside the ACS National Surgical Quality Improvement Program. The aim of the present study is to evaluate the ability of the ACS-NSQIP model to predict the clinical outcomes of patients aged 80 years or older undergoing elective or emergency cholecystectomy. Study design: The study focused on 263 patients over 80 years of age operated on between 2010 and 2019: 174 were treated as emergencies because of acute cholecystitis (66.2%). Outcomes evaluated are those predicted by the ACS-NSQIP calculator within 30 days of surgery. The ACS-NSQIP model was tested for both discrimination and calibration. Differences among observed and expected outcomes were evaluated. Results: When considering all patients, the discrimination of mortality was very high, as it was that of severe complications. Considering only the elective cholecystectomies, the discrimination capacity of ACS-NSQIP risk calculator has consistently worsened in each outcome while it remains high considering the emergency cholecystectomies. In the evaluation of the emergency cholecystectomy, the model showed a very high discriminatory ability and, more importantly, it showed an excellent calibration. Comparisons between main outcomes showed small or even negligible differences between observed and expected values. Conclusion: The results of the present study suggest that clinical decisions on cholecystectomy in a patient aged 80 years or older should be assisted through the ACS-NSQIP model.