THE TREATMENT OF CHRONIC CONSTIPATION IN ADULTS - A SYSTEMATIC REVIEW

OBJECTIVE: To evaluate whether laxatives and fiber therapies improve s ymptoms and bowel movement frequency in adults with chronic constipati on. DATA SOURCES: English language studies were identified from comput erized MEDLINE (1966-1995), Biological Abstracts (1990-1995), and Micr omedex searches; bibliographies; textbooks: laxative manufacturers; an d experts. STUDY SELECTION: Randomized trials of laxative or fiber the rapies lasting more than 1 week that evaluated clinical outcomes in ad ults with chronic constipation. MEASUREMENTS AND MAIN RESULTS: Two ind ependent reviewers appraised each trial's characteristics including me thodologic quality. There were 36 trials involving 1,815 persons from a variety of settings including clinics, hospitals and nursing homes. Twenty-three trials were 1 month or less in duration. Several laxative and fiber preparations were evaluated. Twenty trials had a placebo, u sual care, or discontinuation of laxative control group, and 16 direct ly compared different agents. Laxatives and fiber increased bowel move ment frequency by an overall weighted average of 1.4 (95% confidence i nterval [CT] 1.1-1.8) bowel movements per week. Fiber and bulk laxativ es decreased abdominal pain and improved stool consistency compared wi th placebo. Most nonbulk laxative data concerning abdominal pain and s tool consistency were inconclusive, though cisapride, lactulose, and l actitol improved consistency. Data concerning superiority of various t reatments were inconclusive. No severe side effects for any of the the rapies were reported. CONCLUSIONS: Both fiber and laxatives modestly i mproved bowel movement frequency in adults with chronic constipation. There was inadequate evidence to establish whether fiber was superior to laxatives or one laxative class was superior to another.