A treatment for chronic constipation that is now available over-the-counter was more effective that a drug that needs a doctor’s prescription in a review of ten studies comparing the two.

Both polyethylene glycol, which is marketed as Miralax®, and prescription lactulose, sold under a number of brand names including Cholac Syrup®, Kristalose®, and Enulose®, work by drawing water into the colon and softening stools making them easier to pass.

The two osmotic laxatives can help patients whose intestinal activity is slow because of illness or medicines.  Cancer patients who take opiate pain relievers often have problems with this kind of constipation.

The Cochrane Collaborative reviewed all 10 randomized studies comparing polyethylene glycol to lactulose for chronic constipation.  In all, 322 adults and 546 children were included in their analysis.

They found

Polyethylene glycol (PEG) was better than lactulose in

• number of stools per week.
• form of stool.
• need for additional products to manage constipation.
• for children, but not adults, amount of abdominal pain.

Authors Conclusion

Polyethylene Glycol should be used in preference to Lactulose in the treatment of Chronic Constipation.

SOURCE: Lee-Robichaud et al.,  Lactulose versus Polyethylene Glycol for Chronic Constipation, Cochrane Database of Systematic Reviews 2010, Issue 7.

ACG Annual Meeting 2009 Brief Reports

The American College of Gastroenterology held its Annual Scientific Meeting in San Diego from October 23 – 28, 2009 in San Diego.  Research reported during the meeting included how videorecordings of colonoscopy improved quality tests, the effectiveness of a drug that reduces constipation from opiate drugs, and support for guidelines that call for screening colonoscopy beginning at age 40 for people with a family history of colorectal cancer.

Videos Improve Colonoscopy Performance

When endoscopists knew that their colonoscopies were being recorded on video, their overall performance increased significantly.  They spent more time on each exam and average quality judged on a 1 to 5 scale improved from 2.9 to 3.8.

In a quality improvement program, experienced doctors were not told at first that their colonoscopies were being taped, but digital recordings were made of 8 to 10 tests.  After being told they would be recorded another 10 cases were taped. Both sets of “pre” and “post” awareness tapes were randomly shuffled, reviewed and scored by an expert endoscopist who didn’t know which gastroenterologist did the exam or whether the doctor was aware of not of being recorded.

In reporting the study at the ACG meeting, Douglas Rex, MD, FACG, from Indiana University, concluded,

Videorecording of colonoscopy dramatically changed process quality indicators of colonoscopist behavior toward longer examination time and better technique. Systematic videorecording of colonoscopy may support quality performance of colonoscopy.

ACG Abstract 11, Rex et al. Videorecording Impacts Colonoscopy Performance

Experimental Medicine Helps with Opiate-Induced Constipation

In a randomized, placebo-controlled clinical trial, NKTR-118 increased the number of spontaneous bowel movements in patients with constipation caused by opioid pain medicines.  In addition, the time before the first bowel movement was much shorter than with a placebo. Time before a bowel movement for 25 mg NKTR-118 was 6.6 hours compared to 48.6 hours for placebo and  and 2.9 hours for the 50 mg dose compared to 44.9 with placebo.

NKTR-118 blocks opioid receptors in the gut but does not affect receptors in the central nervous system where opiates work to reduce pain.  There were no opiate withdrawal symptoms or lack of pain relief at any point during NKTR use.

Lynn Webster, MD and colleagues concluded,

In conclusion, the results of this study show that oral NKTR-118 is an effective and safe therapy to normalize GI function in patients with opiate-induced constipation without reversing analgesia.

ACG Abstract 26: Webster et al., Efficacy, Safety and Pharmacokinetics of Oral NKTR-118 in Patients with Opioid-Induced Constipation

Screening Finds Polyps in People from 40 to 49 with a Family History of Colon Cancer

Current ACG guidelines call for screening people with a first-degree relative (parents, brothers, sisters) with colorectal cancer to have screening colonoscopies beginning at age 40.  Doctors at the University of Michigan  reviewed colonoscopies done only for screening in their patients from 40 to 49 who had a first-degree relative with colorectal cancer.  They found adenomatous polyps in 1 in 5, and advanced adenomas in 4 out of 100.

There was no significant difference in either polyps or advanced adenomas depending on whether the relative had been diagnosed with colorectal cancer before or after the age of 60.  However, diabetes did have a significant impact on finding polyps.

Dr. Akshay Gupta and team concluded,

Based upon 21.7% prevalence of adenomas and 3.6% prevalence of advanced adenomas, our data supports current guideline recommendations to begin screening colonoscopy at age 40 among individuals with a family history of colorectal cancer.

ACG Abstract 16A: Gupta et al, Prevalence and Risk Factors for Adenomas in 40-49 Year Old Individuals with a Family History of Colon Cancer