Patterns of emergency department visits preceding colorectal cancer diagnosis: a population-based study.

To assess the patterns of emergency department (ED) visits in the 3 months preceding a diagnosis of colorectal cancer (CRC) in a real-world, population-based context. Linked provincial registries in Alberta, Canada, were accessed and patients with CRC diagnosed between 2004 and 2018 were identified. The National Ambulatory Care reporting system was used to identify patients who visited an ED within 3 months of a diagnosis of CRC. Multivariable logistic regression analysis was used to identify factors associated with any ED visits as well as frequent (≥3) ED visits. A total of 25,310 patients with CRC were included in the current study. These include 10,126 patients (40%) who had at least one visit to the ED in the 3 months before a diagnosis of CRC diagnosis and 613 patients (2.4%) who visited the ED multiple (≥3) times. The following factors were associated with any visit to an ED: older age (odds ratio [OR]: 1.010; 95% CI: 1.008-1.012), female gender (OR: 1.23; 95% CI: 1.16-1.30), higher comorbidity index (OR: 1.38; 95% CI: 1.35-1.41), metastatic disease (OR: 2.37; 95% CI: 2.23-2.53), proximal tumors (OR: 1.59; 95% CI: 1.50-1.68) and North zone (OR vs south zone: 1.75; 95% CI: 1.55-1.98). It is not uncommon for CRC patients to visit the ED at least once in the 3 months prior to having such a diagnosis. Factors associated with frequent pre diagnosis emergency visits included female gender, higher burden of comorbid disease, advanced stage, proximal tumors and living in the North zone of Alberta (where there is limited access to specialist care).