Supplementary Material for: Age-Adjusted Charlson Comorbidity Index Predicts Survival in Endometrial Cancer Patients

Objective: Comorbidity scores are increasingly used to reduce potential confounding in oncologic researches. This is of paramount importance in endometrial cancer (EC) since it is characterized by quite indolent behavior. Here, we aim to evaluate the impact of various comorbidities and concurrent medications used on survival outcomes, adopting the age-adjusted Charlson comorbidity index (A-CCI). Design: This is an observational study. Charts of 257 EC patients were retrieved. Methods: We retrospectively evaluated data of patients who underwent surgical treatment for EC. A-CCI was calculated by summing the weighted comorbidities and age of each patient. A binomial value was assigned to different comorbidities and different drugs. Oncologic outcomes were evaluated using Cox proportional hazard models adjusted for age. Results: A-CCI ≥ 3 correlated with more aggressive tumor features (47.6% vs 26.8%, p= 0.001), higher risk of recurrence (29.7% vs 11.6%, p= 0.001), death (20.7% vs 7.1%, p=0.002) and death due to disease (16.6% vs 6.3%, p=0.012). Considering comorbidities and drugs at parsimonious multivariable analysis model: cardiac disease, liver disease, and proton pump inhibitors (PPIs) use were independent predictors of disease-free survival. Cardiac disease, autoimmune disease, and PPIs use were independent predictors of overall survival. Diabetes was the only independent predictor for cause-specific survival. Limitations: The major limitation of the present study is its retrospective nature and the relatively small sample size that limit the possibility to have firm conclusions. Conclusion: Patients with EC are characterized by a high burden of comorbidities. Comorbidities impact directly survival outcomes. Further attention is needed to improve the active management of comorbidities soon after EC treatments. Interventional studies are needed to improve patients’ outcomes.