Mortality Predictors After Major Abdominal Surgery in Patients Aged 80 and Over: The Role of Frailty and Physiological Reserve

The aim of this study is to identify independent risk factors for 30-day mortality in patients aged 80 and over who have undergone major abdominal surgery. While traditional risk scoring systems often focus on chronic disease burden, they may not fully capture the biological decline associated with aging. This research specifically focuses on the predictive value of "frailty" and "physiological reserve" in determining surgical outcomes for this "old-old" patient population. In this retrospective cohort study, data from approximately 200 patients treated between 2022 and 2025 will be analyzed. Frailty will be assessed using the Modified Frailty Index (mFI-5), and physiological reserve will be evaluated through preoperative laboratory markers such as albumin, creatinine, and lymphocyte counts. By determining how these factors influence postoperative mortality, the study aims to improve preoperative patient selection, enhance risk communication with families, and provide a basis for protective strategies like prehabilitation.