Constipation is one of the most common digestive complaints, affecting more than 30 million adults in the United States. It is the cause of 2.5 million visits to physicians and 92,000 hospitalizations annually. Chronic idiopathic constipation is defined by the infrequent or difficult passage of the stool for a period of at least three months. It may be caused by abnormal colonic motility that can delay the movement of intestinal contents and impede evacuation. The signs and symptoms associated with chronic idiopathic constipation include abdominal pain or discomfort, bloating, straining, and hard or lumpy stools.
Sacral Nerve Stimulation for Constipation: An International Multi-Centre Study
22 May 2007
In patients with idiopathic constipation, which occurs with no identifiable cause, in whom conservative treatment has failed, surgical procedures (e.g., colectomy) are associated with a high failure rate and substantial morbidity. Researchers from five European sites set out to explore an alternative approach: modulating the extrinsic nerve supply to the bowel. In doing so, investigators evaluated the symptomatic response and physiological effect of sacral nerve stimulation in patients with slow transit constipation and normal transit constipation with impaired evacuation.
In this prospective, multi-center trial, 65 patients (58 female) who failed treatment with laxatives and biofeedback (retraining pelvic floor muscle coordination using exercises and electronic aids that create feedback when successful muscle contraction occur) underwent test stimulation, each serving as their own control. The effect of temporary sacral nerve stimulation was assessed by a 21-day bowel habit diary. Patients with more than 50 percent improvement in symptoms were eligible for permanent stimulation. Long-term results were assessed by: bowel habit diary, symptom questionnaire, Cleveland Clinic constipation score (CCCS), visual analogue score (VAS) and short form-36 (SF-36) quality of life questionnaire. Primary endpoints included an increase in the frequency of defecation, reduction in straining and reduction in the sensation of incomplete evacuation.
After a median follow up of 12 months, subjects with both slow transit and impaired evacuation benefited from therapy and 43 patients (66%) proceeded to chronic stimulation. Frequency of defecation increased from 3.4 to 6.1 times per week, while evacuation days per week increased from 2.4 to 4.4. Time spent in facilities decreased from 17.6 to 9.3 minutes, straining decreased from 4.4 to 2.9 episodes per week, abdominal pain decreased from 4.4 to 2.0 days per week, and perception of incomplete evacuation decreased significantly.
In evaluating the results of the various assessment tools set forth at the start of the trial, researchers found that: the CCCS (0=no constipation, 30=severe constipation) decreased from 18.0 to 10.2; mean VAS (0=severe symptoms, 100=no symptoms) increased from 18 to 66; and SF-36 subsets of physical functioning, general health, vitality, social functioning and mental health significantly improved.
"While constipation is rarely life-threatening, associated symptoms of abdominal pain, bloating and the sensation of incomplete evacuation can severely affect the physical and emotional well-being of patients. There are many treatment options for the condition and the best approach relies on a clear understanding of the underlying cause," said Thomas Dudding, M.D., of St. Mark's Hospital in London, England, and lead investigator for the study. "This study found that sacral nerve stimulation is an effective treatment for idiopathic constipation that is resistant to conservative treatment. As a result of this stimulation process, improvement occurs in bowel frequency, associated symptoms and overall quality of life."
Dr. Dudding presented this study.