July 16th, 2012
Selections from Richard Lehman’s Literature Review: July 16th
Richard Lehman, BM, BCh, MRCGP
CardioExchange is pleased to reprint selections from Dr. Richard Lehman’s weekly journal review blog at BMJ.com. Selected summaries are relevant to our audience, but we encourage members to engage with the entire blog.
Arch Intern Med 9 July 2012 Vol 172
Rhythm vs. Rate Control in AF (pg. 992): Two trials in the last decade have stopped cardiovascular medicine in its tracks: AFFIRM and COURAGE. In both cases, a widespread presumption about the superiority of more invasive treatment was proved wrong in a large randomized trial. AFFIRM in 2002 showed that rhythm control is not superior to rate control in atrial fibrillation, and this was later confirmed in the heart failure population (AF-CHF). But some cardiologists have been reluctant to abandon their gut feeling that rhythm control must be intrinsically superior; and this Canadian population study will give them a glimmer of support. There is a tiny difference in favour of rhythm control in observed survival at 9 years; nothing significant at 4 years. Informed patient choice should guide treatment here, as in all areas where there is virtual equipoise.
Diabetes Drugs and Specific Harms and Benefits (pg. 1005): Most oral drugs for type 2 diabetes lower sugar by about the same amount: so does that mean they all have similar effects on end-points? Oddly enough, even very intelligent diabetologists often act on the assumption that they do. Trying to explain choices to patients, they rely on aggregated data showing that for such and such a lowering of HbA1c you will get such and such a lowering of, say, heart attacks or blindness. But convenient though this approach may be, it simply won’t do: everything depends on the agents you use to lower sugar, and we know far too little about them. GlaxoSmithKline has just been fined a billion dollars for concealing data about the cardiovascular risks of its thiazolidinedione drug rosiglitazone (Avandia), and another billion apiece for two unrelated drugs. But you could still argue—from very unconvincing aggregated data—that for patients wishing to avoid eye damage, there might still be a case for using any drug which lowers glucose. This study shows that is not true: both thiazolidinediones (pioglitazone as well as rosiglitazone) are associated with an increased risk of macular oedema in this study using the British primary care THIN database. Both harms and benefits in the treatment of type 2 diabetes are class and agent-specific.
JAMA 11 July 2012 Vol 308
Acadesine and CABG (pg. 157): Last week, I expressed the hope that JAMA Boring might progress to JAMA Slightly Interesting, but this has not happened. Instead, it has turned into JAMA Negative, no doubt for the worthiest of reasons: Effect of Adenosine-Regulating Agent Acadesine on Morbidity and Mortality Associated With Coronary Artery Bypass Grafting: The RED-CABG Randomized Controlled Trial. Red Cabbage! That is so funny. Result: acadesine had no effect.