Predictors of postoperative survival and mortality in nonagenarian surgical patients: a retrospective cohort study

With declining birth rates and increasing life expectancy, the number of patients over 90 years of age, referred to as “nonagenarians” has been steadily rising. Parallel to this demographic shift, the number of surgical procedures performed in this population has also increased. Although several recent studies have examined survival and mortality predictors in very elderly patients, clear definitions are still lacking. This study aimed to identify factors associated with short- and long-term mortality in nonagenarian patients undergoing elective and emergency surgeries, thereby contributing to improved surgical decision-making in this age group. A retrospective analysis was conducted on patients aged ≥ 90 years who underwent surgery at Giresun Training and Research Hospital between November 2021 and April 2023. Demographic data, comorbidities, The American Society of Anesthesiologists (ASA) and modified 5-factor frailty index (mFI-5) scores, laboratory parameters, and intra-/postoperative variables were recorded. Certain inflammatory indices (neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), red cell distribution width (RDW)) were analyzed as prognostic markers. Kaplan–Meier survival analysis and ROC curve analyses were used to determine predictors of 30-day and 1-year mortality. A total of 177 patients (mean age 92.5 ± 2.4 years; 56.1% female) were included. The 30-day and 1-year mortality rates were 14.1% and 36.2%, respectively. Emergency surgery increased early mortality 2.3-fold and 1-year mortality 1.85-fold. Higher ASA and mFI-5 scores, general anesthesia, intensive care unit admission, mechanical ventilation, and perioperative blood transfusion were significantly associated with mortality (p < 0.05). Elevated preoperative NLR, PLR, and RDW levels predicted both 30-day and 1-year mortality (AUC = 0.779, 0.680, 0.664, respectively). Median survival was 261.7 days for emergency and 251.9 days for elective cases and there was no significiant difference (p = 0.343). Surgical decisions in nonagenarians should not rely solely on chronological age. Physiological reserve, frailty, and inflammatory markers play critical roles in determining survival. While elective procedures may be performed safely with appropriate preparation and multidisciplinary management, emergency surgeries carry substantially higher mortality risk. Comprehensive preoperative evaluation and individualized treatment planning may help improve surgical outcomes in this vulnerable population.