Anthranoid laxative use is not a risk factor for colorectal neoplasia: results of a prospective case control study

Background-Anthranoid laxatives are the most commonly used purgatives in th e therapy of acute and chronic constipation. Recent experimental data and a prospective cohort study provide evidence of a possible risk of anthranoid use for the development of colorectal neoplasms. Materials and methods-We performed a prospective case control study at the University of Erlangen to investigate the risk of anthranoid laxative use f or the development of colorectal adenomas or carcinomas. A total of 202 pat ients with newly diagnosed colorectal carcinomas, 114 patients with adenoma tous polyps, and 238 patients (controls) with no colorectal neoplasms who h ad been referred for total colonoscopy were studied. The use of anthranoid preparations was assessed by standardised interview, and endoscopically vis ible or microscopic melanosis col was studied by histopathological examinat ion. Results-There was no statistically significant risk of anthranoid use for t he development of colorectal adenomas (unadjusted odds ratio 1.0; 95% CI 0. 5-1.9) or carcinomas (unadjusted odds ratio 1.0; 95% CI 0.6-1.8). Even afte r adjustment for the risk factors age, sex, and blood in the stools by logi stic regression analysis the odds ratio for adenomas was 0.84 (95% CI 0.4-1 .7) and for carcinomas 0.93 (95% CI 0.5-1.7). Also, there were no differenc es between the patient and control groups for duration of intake. Macroscop ic and high grade microscopic melanosis coli were not significant risk fact ors for the development of adenomas or carcinomas. Conclusion-Neither anthranoid laxative use, even in the long term, nor macr oscopic or marked microscopic melanosis coli were associated with any signi ficant risk for the development of colorectal adenoma or carcinoma.