Shengjie Pan, Gang Wang
Higher WCEI was associated with major complications and less favorable DFS and OS. However, attenuation in the landmark analysis suggests that temporal overlap with early deterioration may partly explain the primary association. Because WCEI may also reflect clinically indicated care intensity and evolving illness, residual confounding, confounding by indication, and reverse causation cannot be excluded. External validation and studies incorporating direct circadian measurements and stronger temporal or experimental designs are needed.
BACKGROUND: The association of potentially circadian-disruptive ward conditions with outcomes after gastrointestinal cancer surgery remains unclear.
METHODS: This prospective cohort included 1500 patients undergoing elective colorectal or gastric cancer surgery between 2017 and 2020. Ward exposures during postoperative days (PODs) 0-3 were summarized using the Ward Circadian Exposure Index (WCEI), an investigational composite of documented ward exposures and care processes. The primary outcome was major complications (Clavien-Dindo grade ≥ III) within 30 days. Disease-free survival (DFS) and overall survival (OS), censored at 60 months, were secondary exploratory outcomes. Multivariable logistic and Cox regression models evaluated associations. WCEI assessment overlapped with the period when early complications could develop.
RESULTS: Among 1500 patients, 183 (12.2%) experienced major complications. Each 1-standard deviation (SD) increase in WCEI was associated with higher adjusted odds of major complications (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.22-1.56; P < 0.001). Within 60 months, 392 DFS events and 268 deaths occurred. Each 1-SD increase was associated with less favorable DFS (hazard ratio [HR], 1.29; 95% CI, 1.18-1.41; P < 0.001) and OS (HR, 1.24; 95% CI, 1.12-1.37; P < 0.001). After excluding 49 patients whose complications were recognized during POD0-POD3, the association with complications recognized during POD4-POD30 was attenuated (OR, 1.24; 95% CI, 1.07-1.44; P = 0.004).
CONCLUSION: Higher WCEI was associated with major complications and less favorable DFS and OS. However, attenuation in the landmark analysis suggests that temporal overlap with early deterioration may partly explain the primary association. Because WCEI may also reflect clinically indicated care intensity and evolving illness, residual confounding, confounding by indication, and reverse causation cannot be excluded. External validation and studies incorporating direct circadian measurements and stronger temporal or experimental designs are needed.