LAS VEGAS — The safety, efficacy, and perhaps most important, the tolerability of bowel preparation for colonoscopy came under intense scrutiny at the annual meeting of the American College of Gastroenterology.
“We desperately need to have one regimen that gives us the ideal preparation,” said Dr. Douglas K. Rex, professor of medicine and director of endoscopy at Indiana University Hospital in Indianapolis.
“Bowel preparation is a very, very big deal,” he continued during the Emily Couric Annual Lecture at the meeting. “We already know it's the thing patients complain about most.”
The problems with bowel preparation are twofold: People who are referred for colonoscopy often don't get it done because they expect the preparation to be inconvenient and uncomfortable, and the difficulties of currently available methods of bowel preparation often lead to incomplete cleansing. The latter problem leads to inadequate visualization in up to 25% of colonoscopies, Dr. Rex added.
“The costs of that over time are enormous,” he said.
One method is the use of aqueous sodium phosphate solutions, which have proven efficacious and reasonably tolerable. However, there is some concern among gastroenterologists about their safety because of problems with electrolyte imbalances, dehydration, and renal failure, Dr. Rex explained.
Polyethylene glycol-electrolyte (PEG-ES) lavage preparations are considered safer but are not as well tolerated, he said.
A third alternative, hydrotherapy, may offer a reasonable alternative, if early studies can be replicated, he said. In a 45-minute procedure immediately preceding colonoscopy, a trained technician uses a pressure-controlled device to lavage the colon with a constant flow of warm water.
In a study presented at the meeting, the hydrotherapy method was compared, on the basis of efficacy and tolerability, with two other methods: 4 L of PEG-ES and aqueous sodium phosphate given in two doses. Patients aged 38–80 years (average age, 61) were randomized to one of the three procedures.
Hydrotherapy received significantly higher colon cleansing quality scores for every area of the colon (right, transverse, and left), compared with either the sodium phosphate or PEG-ES methods, reported Dr. Joseph J. Fiorito of Danbury (Conn.) Hospital. The ratings were completed by endoscopists blinded to the preparation method used.
For example, in the right colon, the quality of cleansing was rated as “good” in 32 of 52 patients (62%) who received aqueous sodium phosphate, 27 of 55 patients (49%) who took PEG-ES, and 49 of 53 (92%) who underwent hydrotherapy.
Patients who received hydrotherapy reported significantly higher scores on measures of ease, convenience, and comfort than patients who underwent other bowel preparation methods.
When patients were asked if they would prefer a different bowel cleansing method if they were to undergo another colonoscopy, 1 of 53 (2%) who had hydrotherapy cleansing said yes, compared with 25 of 52 (48%) of those who took aqueous sodium phosphate and 33 of 55 (60%) who had PEG-ES.
One patient (not included in the final analyses) did not complete the hydrotherapy procedure because of discomfort.
Dr. Fiorito said that the patients in the study were not charged for colonoscopy preparation, but that the estimated cost of hydrotherapy ranges from $35 to $75.
“It would be nice to have insurance companies or Medicare to look at this as an alternative method of preparation,” he said.
Hydrotherapy Inc. of Las Vegas funded the study.
Another study, which was presented as a poster at the meeting, compared a new, 32-tablet form of sodium phosphate preparation with a bowel preparation kit containing 2 L of PEG and bisacodyl tablets.
The study results showed that significantly less irrigation was necessary during colonoscopy and more polyps were identified when subjects took the tablets rather than using the preparation kit.
The new tablet formulation, marketed as OsmoPrep, is made by Salix Pharmaceuticals Inc. of Morrisville, N.C., which sponsored the study.