This week finds us talking about markers for chronic kidney disease (remember we’re no longer allowed to use terms such as renal insufficiency), a bit of positive news about a popular alternative medicine, a new inflammatory marker for coronary artery disease, a genetic basis for atrial fibrillation and most importantly the value of an adequate intake of chocolate.
The 7/3 issue of the Annals of Internal Medicine furthers our knowledge of cystatin c as an eventual replacement for creatinine and gfr. Cystatin c is a serum measure of renal function that appears to be independent of age, sex, and lean muscle mass. In a retrospective analysis, cystatin C levels were more strongly associated with mortality and cardiovacular morality and kidney failure than gfr or creatinine. Slowly it seems, the evidence is accumulating that this is the marker we will all be using in the near future.
A meta-analysis published early online in Lancet Infectious Disease shows that Echinacea both decreased the odds of developing a cold 58% and the duration of a cold by 1.4 days. This is a controversial finding, especially since there are no current standardized products or dosages of Echinacea. It is difficult to recommend a pill that has a variety fo species and quality and has potential interactions as an inhibitor of cytochrome p450. Nevertheless these results are intriguing especially in light of the large number of negative trials recently reported about various herbal medicines. Hopefully further and better studies are on their way.
JACC released an article early online that discussed the use of myeloperoxidase as a cardiac marker. Myeloperoxidase is an enzyme of the immune system and has been shown to be pro-atherogenic by inducing oxidative damage to ldl and hdl and thus promotes plaque vulnerability. After adjustment for traditional risk factors the odds ratio for an elevated MPO level still predicted future risk of coronary artery disease in healthy patients. I expect our patients will soon be clamoring for this test as they did when CRP’s became all the rage.
Even Nature is getting into the act of publishing articles early online prior to their print additions. Last week Nature published an article early online describing the identification of 2 sequence variants on chromosome 4 that are strongly associated with atrial fibrillation in Europeans and Chinese populations. This variant is adjacent to the gene that plays a pivotal role in the development of the heart in terms of left-right asymmetry. This article adds to a growing body of evidence suggesting a genetic contribution to the development of atrial fibrillation. For those of you who know me, I am happy to now blame my father for my irregular heartbeat. (Am I allowed to violate HIPPA about myself?)
And finally every major media outlet had a story about this week’s JAMA article about dark chocolate. Subjects with stage I hypertension were randomized to dark chocolate or white chocolate to determine the effects of cocoa polyphenols which have been shown to improve endoethelial function and reduce bp. In the dark chocolate group systolic blood pressure decreased by a mean of 2.9 mm hg and diastolic by 1.9 without changes in body weight, plasma levels of lipids and glucose a. So clearly a glass of red wine and a hunk of dark chocolate before bedtime will make up for all those dietary indiscretions all day long…
-Neil Shapiro, M.D. Editor In Chief, Clinical Correlations