Study Finds Time Lag Between Positive Fecal Blood Test and Follow-up Colonoscopy
Annual testing for blood in the stool using high-sensitivity guaiac fecal occult blood tests or fecal immunochemical tests is one of several recommended colorectal cancer screening strategies for adults 50 to 70 years old. However, although a positive finding requires a follow-up colonoscopy to evaluate the test results, a study by Chubak et al has found significant variations in the time between a positive result and a follow-up colonoscopy across health-care systems. According to the study results, the probability of a patient having a colonoscopy performed within 1 year ranged from 58.1% to 83.8%, with the oldest patients—those between 70 and 89—at highest risk of not receiving a follow-up colonoscopy. Understanding the variability in follow-up colonoscopy after an abnormal fecal blood test may help providers identify patients needing targeted interventions to complete follow-up. The study is published in Cancer Epidemiology, Biomarkers & Prevention.
Study Methodology
The researchers analyzed data from four U.S. health-care systems on 62,384 patients between the ages of 50 and 89 years old. The four health-care systems were within the Population-Based Research Optimizing Screening Through Personalized Regimens (PROSPR) consortium. All the patients had received a positive result from a fecal blood test between January 2011 and December 2012.
The researchers estimated the probability of follow-up colonoscopy and 95% confidence intervals (CI) using the Kaplan-Meier method. Overall differences in cumulative incidence of follow-up across health-care systems were assessed with the log-rank test. Hazard ratios (HRs) and 95% CIs were estimated from multivariate Cox proportional hazards models.
Study Findings
The researchers found that most patients who received a colonoscopy did so within 6 months of their positive fecal blood test, although follow-up rates varied across health-care systems (P < .001). Median days to colonoscopy ranged from 41 (95% CI = 40–41) to 174 (95% CI = 123–343); percent followed-up by 12 months ranged from 58.1% (95% CI = 51.6%–63.7%) to 83.8% (95% CI = 83.4%–84.3%) and differences across health-care systems were also observed at 1, 2, 3, and 6 months. Increasing age and comorbidity score were associated with lower follow-up rates.
“It is important for providers of health-care systems to know that if a patient hasn’t received a colonoscopy within 6 months of a positive fecal blood test, they are unlikely to in the future—at least not without some further intervention,” said Jessica Chubak, PhD, Associate Investigator at Group Health Research Institute and lead author of this study, in a statement. “Understanding the variability in follow-up colonoscopy after a positive fecal blood test may help health-care providers and systems identify patients in need of targeted interventions to complete follow-up.”
Jessica Chubak, PhD, of Group Health Research Institute, is the corresponding author of this study.
The authors declared no conflicts of interest. Funding for the study was provided by the National Cancer Institute.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
