Colonoscopic Screening for Colorectal Cancer-Impact On Later Need for Usual Care Lower Gastrointestinal Endoscopies

Abstract

Introduction: Colonoscopic screening for colorectal cancer is being implemented in an increasing number of countries. Concerns have been raised about whether the health services are capable of meeting the demand for endoscopic examinations. A change in the need for lower gastrointestinal endoscopies for indications other than post-screening surveillance in a screened population might be important in calculating cost-benefit and demand for endoscopic resources. Aims & Methods: We wanted to investigate whether being invited to a “once only” colonoscopic screening examination for colorectal cancer would affect the demand for later distal gastrointestinal endoscopies for indications other than follow-up of the findings at the screening examinations (usual care endoscopies). In 1996 a screening group of 634 individuals, mean age 67.5 years (range 63-72), randomly drawn from the official population registry, was invited to a colonoscopic screening examination for colorectal cancer. Four hundred and fifty-one (71%) individuals attended. An age and sex-matched control group of 634 individuals was enrolled from the same registry. The control group received ordinary care through the local health service. Both groups belonged to the encatchment area of one single hospital. Distal endoscopies performed in the two groups from January 1996 to December 2004 were registered by investigating medical records. Results: A total of 1268 individuals, 52.4% women, were followed for 9 years. In the screening group, 63 (9.9%) and in the control group, 110 (17.4%) individuals (odds ratio 0.53, 95% confidence interval 0.38-0.73, p < 0 .001) had had a total of 85 and 169 non-screening related distal endocopies respectively (p < 0.001). According to the Norwegian guidelines for post-polypectomy surveillance, 50 (8%) individuals in the screening group had had a total of 64 follow-up colonoscopies in the same period after findings of adenomas at the screening examinations in 1996. Conclusion: We found that in the 9 years following the screening colonoscopy the screening group, compared to the control group, had had 50% fewer lower gastrointestinal endoscopic examinations due to indications other than follow-up of findings at the screening examinations. This indicates that being invited to a colonoscopic screening examination for colorectal cancer might reduce the need for later usual care lower gastrointestinal endoscopies. This finding could have an impact on the estimation of endoscopic resources needed for colorectal cancer screening.