Treatment patterns and health care costs of mebeverine-treated IBS patients: a case-control study

Background: Irritable bowel syndrome (IBS) is a functional disorder affecting the quality of life of patients. In the Netherlands, mebeverine is currently the only medical treatment registered for IBS, although its efficacy is considered disputable.

Objective: To assess treatment patterns and associated health care cost in mebeverine users relative to matched controls.

Methods: A matched case-control study was performed using pharmacy data. Cases were mebeverine users as proxy for IBS patients. Controls were non-mebeverine users and matched to cases by age, gender and pharmacy. Prevalence and incidence of mebeverine use, concomitant drug use and hospitalizations were assessed in 3431 cases and 3431 controls. Concomitant drug use and hospitalizations was also assessed in a subgroup of 1222 users of mebeverine and laxatives (proxy for constipation-IBS) and their controls.

Results: Twelve per 1000 residents were ever-dispensed mebeverine in 1998. One-third of these mebeverine users used laxatives concomitantly. Concomitant drug use and hospitalizations were increased in mebeverine users. The odds ratio for hospitalizations for gastrointestinal reasons was increased predominantly in mebeverine users with concomitant laxative use (OR:8.7; 95%CI [4.3-17.3]). Excess yearly costs for all concomitant medications were 94 Euros [95%CI 79 Euros-109 Euros] and for hospital admissions 120 Euros [74 Euros-166 Euros] per mebeverine user. In mebeverine users with concomitant laxative use these costs were 136 Euros and 251 Euros respectively.

Conclusions: In treated IBS patients, concomitant drug use and hospitalizations are increased relative to matched controls. Medical resource use and associated health care costs are particularly increased in mebeverine users using laxatives. The total mean excess cost per patient per year is 482 Euros.