Dr Chia–Hung Kao and colleagues from Taiwan investigated whether a diagnosis of colonic diverticular disease is associated with an increased risk for subsequent development of colorectal cancer in a nationwide population-based retrospective study.
The researchers identified 41,359 individuals diagnosed with colonic diverticular disease as inpatients from 2000 through 2009 from the Taiwan National Health Insurance Research Database.
The team collected data for 165,436 randomly selected additional subjects, matched by sex, age, and baseline year.
Data were collected until individuals developed colorectal cancer or withdrew from the National Health Insurance system, or until 2010.
|The incidence rate for colorectal cancer in the study cohort was 15.13 per 10,000 person-years|
|Clinical Gastroenterology & Hepatology|
Cumulative incidences and hazard ratios of colorectal cancer development were determined.
To assess for ascertainment bias, the team conducted an analysis excluding the first 12 months of follow-up evaluation.
The researchers found that the risk of colorectal cancer was significantly higher in the study cohort than in the comparison cohort.
In a sensitivity analysis, the researchers excluded the first 12 months of follow-up evaluation after a diagnosis of colonic diverticular disease.
Subsequent incidence rates for colorectal cancer in the study and comparison cohorts were 15.13 and 15.74 per 10,000 person-years, respectively.
Dr Kao's team comments, "Colonic diverticular disease is not associated with an increased risk of subsequent colorectal cancer after the first year of diagnosis of colonic diverticular disease."
"An increased risk was observed in the first year, possibly owing to misclassification and screening effects."