Shortcuts-This Week in the Journals

August 20, 2007

BridgeCommentary By: Neil Shapiro, M.D. Editor-in-Chief Clinical Correlations

As summer winds down and the weather prematurely cools off, this weeks shortcuts finds us focusing on the genetics of coumadin treatment, the very controversial hpv vaccine, and the evils of direct to consumer advertising, and to keep us clean we conclude with a bit about antibacterial soaps and what else you can find at your local drugstore…

The front page of the wall street journal picked up an FDA medwatch advisory approving labeling changes on warfarin to include pharmacogenemoics information. The advisory highlights how a patient’s genetic makeup may influence response to the anticoagulant. Prescribers may need to lower warfarin dose in patients who have variations in the CYP2C9 and VKORC1 genes. The frequency of CYP2C9 variants are 10-20% in Caucasians and African-Americans and 14-37% for VKORC1 . In Asians the VKORC1 is as high as 89%. There is testing available, although I am currently unaware of the costs or availability in our hospital settings. Studies are ongoing to determine the best dosages for patients with this genetic makeup. I am confident that we will increasingly be seeing data and advisories coming from the burgeoning field of pharmacogenetics.

Again highlighting the increasing publication of negative trials, this week’s JAMA has a phase III randomized control trial that looked at patients with cervical specimens that are positive for Human Papilloma Virus (HPV) dna and randomized them to HPV vaccine or a control hepatitis A vaccine. They found no increase in viral clearance in the patients given the hpv vaccine. Thus, the vaccine should not be used to treat current active infection, much to the chagrin of Merck, the manufacturer of Gardisil.

Which leads us to the problem of direct to consumer drug advertisements We’ve all seen patients who can’t wait to tell us about the latest drug that will clearly cure whatever disease they have and then won’t leave the office until a prescription is in hand. Usually an advertisement on televesion or in a magazine has initiated this discussion. The NEJM this week analyzes the current trends. They showed spending increased from $11.4 billion in 1996 to $30 billion in 2005 still only making up 14% of the total promotional costs (that’s even more scary). Most of the campaigns start within one year of approval. More troubling is that letters of violation have decreased from 142 to 21. Disappointingly, the authors of the article take a tepid response in their conclusions, calling only for more studies and evaluation rather than a harder line, like in Canada and the European Union which have banned these advertisements altogether.

The current issue of clinical infectious diseases examines antibacterial soap. Most of these soaps contain an antimicrobial Triclosan. This is a phenoxyphenol antibiotic that can kill many bacteria but is ineffective at inhibiting gram negative bacteria. More importantly there is in vitro data that supports the development of resistance in several bacteria species. This review article concluded that plain soap is as good at reducing bacterial levels on the hands or preventing symptoms of infectious illness, including cough, congestion, diarrhea, sore throat, fever, and vomiting. Thus, it seems the marketing machine without any evidence, has increased the paranoia in consumers who hope to live in a germ free environment. Next we’ll probably see bubble wraps for suburban homes…

Finally if the perception of primary care can get any worse…healthcare is now being sold right next to shampoo at your local Wal-Mart, CVS and Target. The Associated Press reports that by the end of next year 2000 clinics will be open in these stores around the country. The clinics are usually staffed by nurse practitioners and have grown rapidly in the last few years. The AMA has asked the government to look into the obvious conflict of interest in encouraging patients to fill their prescriptions on site. This conversation overheard at the cashier:

Customer: So I’ll take 1 action figure for my son, some shaving cream, toothpaste, some batteries and a physical exam…

Cashier: that’ll be $112…

Image of Bitzer’s Mill Covered Bridge in Lancaster County, Pennsylvania Photo by and (c)2006 Derek Ramsey, courtesy Wikimedia Commons

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