Complications in Medicaid Patients with Irritable Bowel Syndrome and Constipation

San Diego—The majority of Medicaid patients in Missouri with irritable bowel syndrome with constipation (IBS-C) or chronic constipation (CC) had an unmet medical need or treatment failure, contributing to poor disease management and a significant increase in healthcare resource utilization.

Results of the 12-month, retrospective cohort study were presented at DDW at a poster session. The poster was titled Treatment Patterns and Indicators of Unmet Needs/Treatment Failure in Medicaid Patients with Irritable Bowel Syndrome with Constipation and Chronic Constipation.

Examples of an unmet medical need/treatment failure included switching constipation treatments, augmenting therapy with an additional constipation treatment, and IBS- or constipation-related inpatient or emergency department admission while on treatment.

In the United States, approximately 5% to 10% of people have IBS-C and 12% to 19% have CC. Both diseases are associated with abdominal symptoms and unsatisfactory defecation, and treatment options are similar.

People with IBS-C or CC are advised to undergo lifestyle modifications or receive therapies such as over-the-counter (OTC) laxatives, bulking agents, and stool softeners. Lubiprostone is the only drug that is FDA-approved to treat both diseases.

The authors noted that clinicians sometimes prescribe off-label therapies such as rifaximin or colchicine if patients fail treatment with standard therapies, which can lead to complications, including fecal impaction and megacolon. Other potential problems include intense abdominal pain or colectomy. The authors consider these events indicators of unmet needs or treatment failures that could cause an economic burden to patients and payers.

The analysis was based on deidentified medical claims from the Missouri Medicaid database from the first quarter of 1997 to the fourth quarter of 2010 that included medical and pharmacy dispensing claims as well as enrollment history.

Patients were considered as having IBS-C if they received OTC or prescription medications ≤1 year after being diagnosed as well as ≥2 diagnoses for constipation. Patients with CC had received ≥2 diagnoses for constipation or constipation treatments >60 days but <1 year apart. All patients were ≥18 years of age.

The analysis included 2830 patients with IBS-C and 8745 patients with CC. They were stratified into 2 cohorts based on whether they had indicators of unmet needs/treatment failure.

During the 12 months, 46.3% of patients with IBS-C and 54.9% of patients with CC had ≥1 indicator of unmet needs/treatment. When considering patients’ entire continuous eligibility periods, 75.9% of patients with IBS-C and 78.7% of patients with CC had ≥1 indicator of unmet needs/treatment. The median study period length was 4.9 years.

In both groups, the most frequent indicator of unmet needs/treatment failure was treatment switching, occurring in 68.7% of patients in the IBS-C group and 74.6% of patients in the CC group.

Within 2 years of beginning treatment, 61.0% of patients in the IBS-C group and 65.5% of patients in the CC group had experienced an unmet need or failed treatment. Within 4 years, those rates increased to 75.3% and 78.2%, respectively.

The authors found that patients who had unmet needs or treatment failure had significantly higher levels of healthcare resource utilization. After adjusting for baseline differences, there was a 66% increase in the number of inpatient admissions in patients with IBS-C and a 52% increase in the number of inpatient admissions in patients with CC when they had an unmet need/treatment failure (P<.001 in both cases).

The rate of outpatient admissions was significantly higher for patients in the IBS-C group who had indicators of unmet needs, but it was not significant for patients with CC.

The study was funded by Forest Laboratories, Inc. and Ironwood Pharmaceuticals, Inc.