Is Isotretinoin Innocent from Causing Inflammatory Bowel Disease?

Objectives: Multiple case reports suggesting isotretinoin causes inflammatory bowel disease leading to compensations reaching millions of dollars. New larger studies question this effect. This is a meta-analysis to study the association. Methods: We searched PubMed, Cochrane, Google Scholar, and WorldCat. We extracted six articles measuring drug exposure and disease incidence. We measured the effects of isotretinoin on inflammatory bowel disease, Crohn’s disease and ulcerative colitis, using pooled odds ratio. The effect can be measured using the fixed or the random model. The fixed effect assumes studies have the same effect in the same population, while the random assumes heterogeneity. The correct model is chosen based on a Q-heterogeneity test. Results: Sample size was 9723864. Inflammatory bowel disease in isotretinoin exposed had an odds ratio of {1.075, 95% confidence interval (0.78, 1.49)}, Crohn’s disease{0.97, 95% confidence interval (0.65, 1.43)} and ulcerative colitis {1.28, 95% confidence interval (0.88, 1.86)}. All odds ratios had a p-value > 0.05 using the random-model which was chosen due to significant Q and I-squared score p value < 0.05. There was significant heterogeneity of the six studies, which lack consistency in adjusting for important co-variables (dose, family history, smoking, etc.)