Association between socioeconomic status and postoperative outcomes after esophagectomy within a universal healthcare system: a nationwide population-based cohort study.

INTRODUCTION: Socioeconomic status (SES) is associated with disparities in cancer outcomes. The relationship between SES and postoperative outcomes after esophagectomy is inconsistent, especially within low-threshold universal healthcare systems. We hypothesized that lower SES would be associated with higher rates of postoperative complications, and longer length of hospital stay (LOS). MATERIALS AND METHODS: This retrospective nationwide cohort study used Dutch Upper Gastrointestinal Cancer Audit (DUCA) data. All patients aged ≥18 years undergoing esophagectomy between 2014 and 2023 were included. SES was based on neighbourhood-level data derived from Statistics Netherlands (CBS). Patients were assigned to three SES groups (low, middle, high). Outcomes included severe postoperative complications and other postoperative outcomes, including length of stay (LOS) and mortality. Multivariable regression adjusted for confounders. RESULTS: Among 6658 patients, lower SES groups had a higher comorbidity burden, with American Society of Anaesthesiologists (ASA) physical status ≥ III in 32·3% of low SES patients, compared with 27·2% and 26·0% in middle and high SES groups. In univariable analysis, high SES was associated with a lower risk of prolonged intensive care unit (ICU) stay (OR 0·78, 95% CI 0·67-0·91) and LOS (β -1·60 days, 95% CI -2·90 to -0·34). After adjustment, SES was not independently associated with postoperative outcomes. CONCLUSION: SES was not associated with postoperative outcomes after esophagectomy. Lower SES groups had higher comorbidity burden, which may explain the attenuation of the association after adjustment for clinical risk factors. These findings suggest that within a low-threshold universal healthcare system, postoperative outcomes after esophagectomy may be primarily determined by clinical factors rather than SES.