Chronic Constipation Treatment Efficacy Review
Patient Dissatisfaction with Treatment
Approximately 50% of patients suffering from chronic constipation express dissatisfaction with their treatment, primarily due to inadequate efficacy. A recent review conducted in the United States and published in the journal Gut evaluated the effectiveness of various treatment options for chronic constipation.
Understanding Chronic Idiopathic Constipation
Chronic idiopathic constipation (CIC) affects both men and women equally, although its prevalence increases among individuals over 65 years of age. The most common symptom reported by patients is the presence of hard, lumpy stools.
First-Line Treatment Options
Initial treatment strategies focus on enhancing dietary soluble fiber intake or utilizing psyllium fiber products, such as Metamucil. If patients do not experience sufficient relief from these measures, five drug classes are available for treating chronic constipation.
Available Drug Classes
The five drug classes indicated for chronic constipation include:
– Diphenyl methanes (e.g., bisacodyl and sodium picosulphate)
– 5-hydroxytryptamine receptor 4 agonists (e.g., prucalopride)
– Guanylate cyclase C receptor agonists (e.g., linaclotide)
– Two additional classes not currently available in Canada (chloride channel type 2 openers and apical sodium bile acid inhibitors)
Network Analysis of Drug Efficacy
This recent review included a meta-analysis of these five drug classes. Since no single study has assessed the efficacy of all drug classes, a network analysis was performed to compare each drug class against a common comparator based on selected studies. Researchers from the Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER) at the Mayo Clinic reported the findings in Gut.
Study End Points
The primary end points included the number of patients achieving three or more complete spontaneous bowel movements per week, or an increase of one or more complete spontaneous bowel movements per week over baseline. Secondary end points measured the change from baseline in the total number of spontaneous bowel movements per week and the change in complete spontaneous bowel movements.
Effectiveness of Pharmacological Options
A total of 21 studies, involving 9,189 patients, were included in the analysis. The findings indicated that all drug classes outperformed placebo, with comparable efficacy noted for the primary end points. Bisacodyl was observed to potentially offer greater efficacy for secondary end points; however, this conclusion is based on a single study with a treatment duration of only four weeks.
Limitations of the Review
Several limitations were noted in this comparative review. The apparent equal efficacy among the drug classes may stem from the researchers’ inability to categorize patients into specific constipation subgroups, which could influence treatment response. Additionally, the treatment durations varied significantly across studies, ranging from four to 24 weeks. Safety profiles and side effects for each drug were not reported, and certain laxatives, such as polyethylene glycol 3350, lactulose, and magnesium salts, were excluded from the analysis due to inconsistent end points.
Conclusion on Bisacodyl’s Efficacy
The network meta-analysis indicates comparable efficacy among the drugs available for chronic idiopathic constipation, with bisacodyl standing out as superior based on secondary end points. However, bisacodyl is associated with side effects such as cramps and diarrhea. Future studies should aim to compare each drug class directly in terms of both efficacy and safety. Research that categorizes patients according to different types of constipation will further assist healthcare providers in selecting the most suitable treatment for individual patients.
References
(1) Nelson AD, Camilleri M, Chirapongsathorn S, et al. Comparison of efficacy of pharmacological treatments for chronic idiopathic constipation: a systematic review and network meta-analysis. Gut. 2017.
(2) Schoenfeld, P.S. New Treatment Option for Irritable Bowel Syndrome with Constipation and Chronic Idiopathic Constipation. Gastroenterol Hepatol. 2012.