Systematic review of the effectiveness of laxatives in the elderly.

OBJECTIVES To determine the effectiveness and cost of laxatives in the prevention and treatment of constipation in the elderly. HOW THE RESEARCH WAS CONDUCTED Randomised controlled trials (RCTs) of treatment or prevention of constipation were included in the review. INTERVENTIONS The four classes of laxatives, bulk, osmotic, stimulant laxatives and faecal softeners, were covered by the review. The main laxatives included in the trials were bran, psyllium, prucara, cascara, dioctyl sodium, lactulose, and lactitol. PARTICIPANTS Elderly people suffering from chronic functional constipation. A trial was eligible for inclusion if all participants were aged 55 years or older and being treated for chronic constipation. The trials reviewed did not provide further subcategorisation by aetiology. MAIN OUTCOMES Number of bowel movements per week; symptom improvement; stool consistency; abdominal pain. DATA SOURCES The recent systematic review by Tramonte and colleagues was used as a source of trials (J Gen Intern Med 1997;12:15-24). In addition, the following databases were searched: Embase, Psychlit, Medline, the Cochrane library, the nursing database CINAHL, International Pharmaceutical Abstracts, and the alternative therapies database, AMED. Authors and manufacturers were also asked for information. Studies in any language were eligible for inclusion. Decisions on the relevance of primary studies were made independently by two reviewers. Economic information was searched for in Current Contents/Clinical Medicine, Medline, and the NHS Economic Evaluation Database (NEED). VALIDITY ASSESSMENT: The quality of primary studies was summarised on a 6-item scale. This covered reporting of inclusion and exclusion criteria, randomisation method, standardised assessmment of adverse effects, double-blind design, description of withdrawals, and statistical analysis. The assessment of validity of included studies was carried out independently by two reviewers. Data were extracted from studies independently by two reviewers. Authors were contacted for more information where necessary to obtain unpublished information. CLINICAL TRIALS INCLUDED Ten trials comparing single agents with placebo were identified, with a total of 367 patients were identified, with a total of 367 patients who had a mean age of about 74 years. Two of these presented no information on the numbers of men and women (54%) in the remaining eight trials. The majority of patients were in an institutional setting, such as a nursing home or hospital. Ten trials compared one laxative agent with another. The mean age of participants in these trials was estimated at 77 years. Only one trial examined patients in an outpatient setting; the other trials were carried out in nursing homes or hospitals. (ABSTRACT TRUNCATED)