Wait times for diagnostic colonoscopy among outpatients with colorectal cancer : A comparison with Canadian Association of Gastroenterology targets

1Department of Medicine, Division of Gastroenterology; 2Department of Surgery; 3Department of Pathology, University of Western Ontario, London, Ontario Correspondence: Dr Michael Sai Lai Sey, London Health Sciences Centre – Victoria Campus, 800 Commissioners Road, London, Ontario N6A 5W9. Telephone 519-667-6582 ext 5, fax 519-667-6820, e-mail msey2@uwo.ca Received for publication February 4, 2012. Accepted May 2, 2012 Colorectal cancer is the second leading cause of cancer-related mortality in Canada. An estimated 22,200 new cases were diagnosed in 2011, with 8900 deaths (1). Phase III randomized clinical trials are currently underway to determine the efficacy of screening colonoscopies for reducing colorectal cancer-related mortality (NCT00906997, NCT00883792 and NCT01239082), although the results will not be available for at least a decade. In the interim, multiple observational studies have already documented a reduction in colorectal cancer mortality associated with colonoscopy (2-5). However, timely access to specialist care is a challenge in Canada. In the National Health Services Access Survey (6), one in five Canadians experienced difficulty accessing specialist care, resulting in excess worry, anxiety and stress. A nationwide practice audit of wait time for endoscopy (7) revealed a median and 75th percentile wait time of 91 and 203 days, respectively. In response to these challenges, the Canadian Association of Gastroenterology (CAG) developed a consensus statement for maximal acceptable wait times for digestive health care (8). The consensus statement addressed maximal wait times for consultation or procedure for a variety of indications (Table 1). However, two follow-up studies after the publication of the consensus statement continued to reveal long wait times (9,10). Although these studies highlight the long wait times patients endure for general digestive health referrals, the direct impact of diagnostic delays among patients with a time-sensitive diagnosis, such as colorectal cancer, remains unknown. The primary objective of the present study was to determine the wait time for diagnostic colonoscopy among patients with colorectal cancer. The secondary objective was to determine the association between wait times and cancer stage. oriGinAl ArtiCle

There are no specific citywide triage guidelines in London, and triage is left to the discretion of the individual endoscopists' office.There are a limited number of urgent outpatient endoscopy slots available weekly at each hospital.
Wait times were stratified according to CAG referral indications and compared with targets to determine the percentage of patients exceeding suggested maximal wait times.Mean, median and range of wait times were also determined.Cancer stage was compared with wait times for colonoscopy.

Statistical analysis
Descriptive analysis was completed for the study sample (mean, median, range and SD).The difference in the number of patients exceeding target wait times for each indication and according to cancer stage was analyzed using Fisher's exact test.Differences in mean wait time as a function of cancer stage was analyzed using ANOVA.P<0.05 was considered to be statistically significant.

RESULTS
A total of 185 patients were endoscopically diagnosed with colorectal cancer in 2010.Seventy-nine cases were excluded (27 were not new referrals, 33 diagnosed as inpatients, 12 had a history of colorectal cancer, one had a history of inflammatory bowel disease and six had insufficient information regarding referral date/indication).One patient, who was diagnosed as an inpatient, was awaiting outpatient colonoscopy when he was admitted to hospital with hematochezia and underwent an inpatient colonoscopy instead.A total of 106 cases were included in the study (Table 2).Seventy-nine per cent of patients had consultation and underwent colonoscopy on the same day.
Forty-six per cent of patients with colorectal cancer exceeded wait time targets, with no significant differences among referral indications (P=0.99)(Table 3).The overall mean (± SD) wait time for all indications was 79±101 days.Three patients delayed their colonoscopy date due to personal reasons.
Patients with stage I colorectal cancer had the longest mean wait time, which decreased with increasing cancer stage (P=0.003)(Figure 1).There were no significant differences in the percentage of patients exceeding wait-time targets for each cancer stage (P=0.30)(Figure 2).

DISCUSSION
Outpatients in London, Ontario, experience long delays for diagnostic colonoscopy for colorectal cancer, with 46% of cases exceeding CAG targets.Although mean and median wait times appear to approximate CAG targets, they should be interpreted with caution because a patient with a short wait time should not compensate for a patient with a long wait time.This is reflected in the wide range of wait times, with some patients having very short waits if urgent endoscopy slots are available.For this reason, we focused our study on the number of patients who exceeded CAG wait time targets as a more important representation of total wait times.
Among patients with stage 1 colorectal cancer, the mean wait time was in excess of 150 days.It is possible that earlier colonoscopy with  polypectomy in this subgroup before progression from high-grade dysplasia to invasive adenocarcinoma could be curative and avoided the need for surgery.
Since the publication of the CAG consensus statement, several studies have reported on wait times for digestive health care in Canada.In a single-centre study from Queen's University (Kingston, Ontario), Yu et al (10) reported a mean wait time of 229 days, with 78.6% of cases not meeting CAG targets.In a nationwide survey, Leddin et al (9) reported a mean wait time of 155 days.However, these studies only addressed wait times for general digestive health referrals.Thus, the wait times for those with a time-sensitive diagnosis, such as colorectal cancer, remain unknown.Singh et al (12) partially addressed this issue in a population-based study of wait times from presentation to treatment for colorectal cancer in Manitoba.They reported a colonoscopy wait time of 54 days, which was comparable with our results.However, multiple assumptions had to be made because the data were derived from health registries.Although not directly comparable, the sum of these studies with ours suggests that long wait times continue to be a challenge in Canada.
Long wait times directly impact patients and contribute to anxiety, lost time from work and social functioning (13).Of greater concern is the potential that diagnostic delays enable the development of more advanced cancers.However, our study demonstrated an inverse relationship with stage I cancer having the longest wait time.This is likely due to triaging of referrals because advanced cancers often have more urgent presentations.At its root, the CAG consensus statement is itself a triaging tool.Other studies attempting to demonstrate a relationship between diagnostic delay and cancer stage have also produced conflicting results (14)(15)(16).
One limitation of our study was its single-city design, which only reflects wait times in London, Ontario.However, because a national database on colonoscopy wait times does not exist, studies such as ours provide insight into this important issue.Another limitation of our study was its retrospective design, which although subject to more bias, enables the most thorough collection of cases.Our selection of hard outcomes, such as the presence of cancer and wait times, also limits bias in our study.Finally, 44% of our cases were rectal cancers, which is higher than expected and may represent a referral bias in our study population.
Long wait times for diagnostic colonoscopy among patients with colorectal cancer have persisted since the publication of target wait times.Strategies to enable timely access to colonoscopy for patients suspected of having colorectal cancer are needed.

Table 1 Canadian association of Gastroenterology maximal wait times for selected referral indications Indication Maximal wait time
All cases of histologically confirmed colorectal cancer diagnosed at colonoscopy during the study period were retrieved from the citywide pathology database.Only new referrals to the endoscopist (15 gastroenterologists, two internists and 11 general surgeons) were included in the study.Exclusion criteria included patients who were not a new referral to the endoscopist, inpatient procedures, history of colorectal cancer, familial cancer syndrome and inflammatory bowel disease.Outcomes Demographic data (age, sex), referral date and indication (based on faxed referral form), consultation and endoscopy date, and cancer stage (American Joint Committee on Cancer: tumour, node, metastasis staging) (11) were determined.Referral indications were sorted into categories used in the CAG consensus statement (Table