The direct and indirect impact of comorbidity on the survival of patients with non-small cell lung cancer: a combination of survival, staging and resection models with missing measurements in covariates

Objective To examine the direct and indirect impact of comorbidity on the survival. Design A historical cohort study. Setting Denmark. Participants All patients with non-small cell lung cancer who were registered in the Danish Lung Cancer Registry in 2010. Main outcome measures The influence of comorbidity on stage misclassification, probability of resection and survival. Results It was estimated that the comorbidity influences the probability of resection with OR 0.65 and 95% credible interval (0.54; 0.79), the staging process with OR 1.08 and 95% credible interval (0.96; 1.20), and the survival process with HR 1.08 and 95% credible interval (1.02; 1.14). Conclusions We found that comorbidity has a significant indirect effect on survival mediated by the resection process and a slightly direct effect on mortality.