August 11th, 2014
Selections from Richard Lehman’s Literature Review: August 11th
CardioExchange is pleased to reprint this selection 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.
Lancet 9 August 2014 Vol 384
Effects of Intensive Glycemic Control on Ischemic Heart Disease (OL): Awaiting appearance in the printed Lancet is a re-analysis of data from the ACCORD trial of intensive glucose lowering in high risk type 2 diabetes, showing that those who attained the target reduction of blood glucose showed a reduction in cardiovascular events. Uh? Wasn’t the ACCORD trial stopped early because of an excess of cardiovascular deaths in the intensive treatment group? Why yes, but this is not enough to deter the authors of this paper from contesting the evidence. Those deaths, they argue, occurred in those whose blood sugars did not respond to the additional treatment. People who attained the desired level of HbA1c actually had fewer myocardial infarctions (by a just significant 15%), they observe, adding in observational data from after the study had been curtailed. So intensive treatment, they argue, works for those whose blood sugar falls. Yes, I can accept that may be true, but that doesn’t alter the main message of ACCORD, which is that for each one who benefits there is another who is harmed. We know that, observationally, blood sugar is a continuous risk factor for myocardial infarction: what we still don’t know is how best to reduce this risk in individuals. This analysis certainly does not reverse the message of ACCORD, but suggests a hypothesis that needs a new trial in clinical practice.
Effect of Treatment Delay, Age, and Stroke Severity on the Effects of Intravenous Thrombolysis with Alteplase for Acute Ischemic Stroke (OL): I have followed the saga of thrombolysis for stroke from its beginnings in the early 1990s, and I remain deeply ambivalent. Doctors typically want less treatment for themselves than they inflict on their patients. If I am severely hemiplegic, or have difficulty swallowing, or impairment of consciousness, do not give me thrombolysis. Do not give me fluids or food. Do not give me antibiotics. Take it that I want to die, and help me to die reasonably quickly and reasonably well. I know there is a small chance that I might recover and live some kind of life, but I would rather not take it. The thrombolysers, however, ignore all this—or rather downplay it. There is an “average absolute increase in disability free survival of about 10% for patients treated within 3.0 h and about 5% for patients treated after 3.0 h, up to 4.5 h.” These figures come from a meta-analysis of individual patient data from 6756 patients in nine randomised trials. “The proportional benefits were similar for patients aged older than 80 years compared with younger patients, and for patients with minor or severe strokes compared with other patients.” But I don’t really understand how you can apply these figures to individuals with their own personal, evolving strokes, let alone share the decision making in real time.