The objective of this review was to determine the effects of management strategies for faecal incontinence and constipation in people with neurological diseases affecting the central nervous system.
Individuals with neurological disease have a much higher risk of both faecal incontinence and constipation than the general population. There is often a fine dividing line between the two conditions, with any management intended to ameliorate one risking precipitating the other. Bowel problems are the source of much anxiety and may reduce quality of life. This review is relevant to individuals with any disease with a pathological process directly and chronically affecting the central nervous system (post-traumatic, degenerative, ischaemic or neoplastic), such as multiple sclerosis, spinal cord injuries, cerebrovascular diseases, Parkinson's disease and Alzheimer's disease.
While there is considerable literature on the causes of neurogenic bowel dysfunction, there are few studies that focus on the practical management. Currently such individuals are commonly advised to have a good fluid intake, a balanced diet, sufficient physical exercise, scheduled bowel routine and moderate use of medications. Bowel management employs a combination of medications (e.g. bulking agents, laxatives, enemas) and mechanical interventions (e.g. digital stimulation, manual evacuation, abdominal massage, rectal irrigation) established on a trial and error basis.
The ten randomised studies included in this review reported small samples and were mostly of poor quality. Oral medications for constipation were the subject of four trials. Cisapride does not seem to have clinically useful effects in people with spinal cord injuries (three trials). Psyllium was associated with increased stool frequency in people with Parkinson's disease but not altered colonic transit time (one trial). Prucalopride did not demonstrate obvious benefits in this patient group (one study). Some rectal preparations to initiate defecation produced faster results than others (one trial). Different time schedules for administration of rectal medication may produce different bowel responses (one trial). Mechanical evacuation may be more effective than oral or rectal medication (one trial). Patients may benefit from even one-off educational interventions from nurses (one trial).
There is still remarkably little research on this common and, to patients, very significant condition. It is not possible to draw any recommendation from the trials included in this review. Neurogenic bowel management must remain empirical until well-designed controlled trials with adequate numbers and clinically relevant outcome measures become available.