ShortCuts-This Week in the Journals

October 9, 2007

tropicair1.jpgCommentary by Josh Olstein MD, Associate Editor, Clinical Correlations

As a future gastroenterologist, I was drawn to a study in the October 4th edition of the New England Journal of Medicine that compared CT colonography with colonoscopy for the detection of advanced neoplasia.  Results from roughly 6300 patients who were non-randomly referred for colon cancer screening by either modality were compared and the main outcome measures included the detection of advanced neoplasia and total number of harvested polyps.  Advanced neoplasia included carcinomas or advanced adenomas defined as having one or more of the following:  size >10mm, presence of substantial villous component, or the presence of high-grade dysplasia.  There was no difference in the number of advanced neoplasia found in the CT colonograph group and colonoscopy group (123 and 121 respectively) however the primary colonoscopy group had significantly more polypectomies.  Of the 3120 patients who underwent CT colonography 12.9 % had findings of at least one polyp >6mm of which 7.9% ultimately had colonoscopy with polypectomy.  Extracolonic imaging findings that necessitated further study or procedures were discovered in 10.7% of the CT group.  The optimal use of this technology to complement colonoscopic screening programs remains unclear but the ability to detect advanced lesions appears equivalent.

A study in the British Medical Journal aimed to shed more light on the effect of oral contraceptives and risk of cancer.  Using data from a large cohort which included over one-million patient years in total from 46,000 women, rates of various cancers were compared among never users and ever users of oral contraception.  Total cancer rates were decreased among the ever users of OCPs including significant decreases in colorectal cancers, uterine, and ovarian tumors.  Overall, there was a 12% reduced risk of any cancer in the primary data set.  There were trends towards increased risk however of cervical and CNS (including pituitary) tumors among ever users of OCPs.  Weaknesses of the study included large losses of follow up among the relatively young and healthy women who were included in the study.

While women in the UK may benefit from OCPs, a study from JAMA suggests that in the US, they are less likely to receive the opportunity to benefit from ICDs when indicated.  Using data from Medicare claims between 1999 and 2005, patients were identified as being eligible for ICD implantation for either primary or secondary prevention indications.  Rates of ICD implantation were then assessed and compared according to gender.  In both the primary and secondary prevention group men were significantly more likely than women to receive ICDs when controlling for multiple variables (HR =3.15, 95% CI 2.86-3.47 for primary prevention, HR=2.44, 95% CI 2.30-2.59 for secondary prevention).  Significant differences were also found when examining rates of ICD implantation according to racial groups with black patients receiving fewer ICDs then white patients in the study.  While the study had several weaknesses including lack of ejection fraction data, data suggests that physicians must be more vigilant in offering these therapies to all our patients, especially those with secondary prevention indications who benefit the most.

Lastly, a study from the Annals of Internal Medicine reports the results from a randomized non-blinded clinical trial of telbivudine versus adefovir for the treatment of chronic active hepatitis B.  Both medications are known to be effective but had not previously been compared head to head.  Treatment naïve adults with HbeAg positivity were randomized to either treatment for 24 weeks and the primary endpoint was reduction in serum HBV DNA levels at 24 weeks.  The results showed reductions in HBV DNA levels that were significantly lower in the telvivudine group compared to the adefovir group.  Patients who were continued on treatment through 52 weeks showed maintained results.  The frequency of adverse events were similar between the groups.  While data regarding long-term efficacy is absent in this study, the data suggests an increasing role for the use of telbivudine in the treatment of chronic active hepatitis B.

One Response to ShortCuts-This Week in the Journals

  1. Charles Maltz on October 10, 2007 at 1:51 pm

    Thanks for the nice summary. Two comments regarding the GI/Liver articles:

    The NEJM study comparing virtual colonoscopy to optical colonoscopy also revealed that 8 non colonic tumors were identified with the CT scan as compared to zero (as expected) with the optical colonoscopy. I think is is also important that 7 iatrogenic perforations occurred with the approach of optical colonoscopy for screening versus zero for the CT approach.

    The Annals article comparing telbivudine to adefovir is somewhat outdated since both telbivudine and adefovir result in a not insignificant resistance after several years of use. Neither one would, in my opinion, be the best Rx for chronic hepatitis B as a single agent. Entecavir, on the other hand has an almost zero resisitance in the treatment naive patient. Perhaps the best use for telbivudine would be as an add on in the patient who had been on adefovir and developed resistance.

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