New Study Finds Better Data on IBS Drug Discontinuation

Eric D. Shah, MD

New data showed drug discontinuation is a common problem for patients with irritable bowel syndrome (IBS).

Investigators, led by Eric D. Shah, MD, evaluated the reasons and timing of discontinuation of different US Food and Drug Administration (FDA) approved pharmacotherapies for irritable bowel syndrome and chronic idiopathic constipation.

In the observational real-world cohort, the investigators identified patients initiating lubiprostone or linaclotide within the University of Michigan Electronic Medical Record (2012-2016).

The investigators determined medication start and stop dates in manual chart reviews including detailed reviews of all documentation such as office notes and telephone encounters. The team then constructed a Cox model to predict the hazard of discontinuation.

The multivariate analysis included 1612 patients, where linaclotide users had a lower risk of discontinuing therapy than lubiprostone users for any reason (HR, 0.6; 95% CI, 0.5-0.8). They also found that at 3 and 12 months, the overall discontinuation rates were 23% and 43% for lubiprostone compared with 14% and 24% for linaclotide.

For the first year of therapy, more than half of the discontinuations were because of intolerance that occurred in the first 3 months for both drugs. Linaclotide users were more likely to discontinue because of intolerance than lubiprostone users (HR, 1.6; 95% CI, 1.2-2.3), but less likely to discontinue due to insufficient efficacy of therapy (HR, 0.5; 95% CI, 0.4-0.8).

Irritable bowel syndrome diagnosis also increased the hazard of discontinuation of lubiprostone relative to linaclotide (HR, 1.4; 95% CI, 1.1-1.6).

The main reason for discontinuation over the first year of therapy is a loss of prescription drug coverage. The investigators believe the study could help better inform the patient-centered discussion centered around the comparative outcomes of discontinuations.

“Individuals appear more likely to discontinue lubiprostone than linaclotide overall, but more likely to discontinue linaclotide compared with lubiprostone due to intolerance (mostly diarrhea),” the authors wrote. “Most discontinuations due to intolerance occur in the first 3 months. These results may be useful in individualized treatment selection and enhancing patient knowledge regarding long-term outcomes.”

Stool microbial diversity and composition are directly linked to daily extraintestinal symptoms, stool consistency, and quality of life for women with IBS.

A team led by Emily B. Hollister, PhD, Department of Pathology and Immunology, Texas Children’s Microbiome Center, evaluated the relationship of fecal microbiota to gastrointestinal symptoms, stool consistency, psychological distress, extraintestinal pain, and quality of life in patients meeting the Rome III criteria for IBS.

Altered microbial diversity has been associated with gastrointestinal symptoms in patients with irritable bowel syndrome. However, there is not much known about the link between microbiome with extraintestinal pain and psychological distress symptoms and quality of life in patients with IBS.

The study included 76 women who completed a 28-day diary that included gastrointestinal symptoms, stool consistency, psychological distress, and extraintestinal pain ratings.

“There was a significant group effect for the Firmicutes to Bacteroidetes ratio and PC1,” the authors wrote. “Lower microbial diversity and richness were associated with increased urgency and extraintestinal pain, worse [quality of life], and looser stools.”

The study, “Evaluating When and Why Patients Discontinue Chronic Therapy for Irritable Bowel Syndrome With Constipation and Chronic Idiopathic Constipation,” was published online in The American Journal of Gastroenterology.