November 18th, 2013
Selections from Richard Lehman’s Literature Review: November 18th
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.
NEJM 14 Nov 2013 Vol 369
Combined Angiotensin Inhibition for the Treatment of Diabetic Nephropathy (pg. 1892): Blockade of the renin-angiotensin-aldosterone system has been one of the therapeutic triumphs of the last 30 years. Or has it? It has certainly brought in tens of billions of dollars in profit to drug companies. For patients with systolic heart failure, ACE inhibitors, or ARBs can bring about modest improvements in survival for some patients, though we do not know how these drugs would compare with, say, the old aldosterone blocker spironolactone used in low doses as first-line treatment. ARBs and ACE inhibitors also provide extra options for the treatment of high blood pressure, but they seem less effective at preventing stroke than thiazide diuretics. And they reduce albuminuria in diabetes, but there is only weak evidence that they confer any greater protection against end-stage renal failure than other BP lowering agents. Despite three decades of hype, I suspect the world would not be much different without them. As for combining ACE inhibitors with ARBs in diabetic patients with albuminuria, don’t go there: the VA NEPHRON-D trial reported here is only one of three which has been stopped early for harm, despite reducing albumin excretion in these patients. A mournful editorial observes that ” The results suggest that improvement in surrogate markers—lower blood pressure or less albuminuria—does not translate into risk reduction. Does this invalidate the relatively new risk marker albuminuria and the classic risk factor blood pressure as therapeutic targets in our patients with type 2 diabetes?” Well, yes, actually. There are no short cuts. With every single agent, you need to find out what happens to patients.
Publication of Trials Funded by the National Heart, Lung, and Blood Institute (pg. 1926): Failure to publish the results of clinical trials is a breach of medical ethics, argued Iain Chalmers over 20 years ago, and I agree. In a BMJ editorial a couple of years ago I suggested it should be a matter for disciplinary action. And this doesn’t by any means apply just to the pharmaceutical industry. In this paper, researchers from within the US National Heart, Lung, and Blood Institute (NHLBI) Division of Cardiovascular Sciences look at the publication of reports from research funded by their institution. At 30 months after data collection was complete, only 57% of the trials had been published. Fortunately this figure included most of the most heavily funded trials with patient important outcomes.
JAMA Intern Med 11 Nov 2013
Sex Differences in ACS Symptom Presentation in Young Patients (pg. 1863): Medical lore has it that women with myocardial infarction are more likely than men to present without typical chest pain, and this is confirmed in this study which looked at the presentation of MI in 1015 patients aged 55 or less: 19 % of women presented without chest pain compared to 13.7% of men. “Patients without chest pain reported fewer symptoms overall and no discernable (sic) pattern of non–chest pain symptoms was found.” But then the authors suggest that “Strategies that explicitly incorporate assessment of common non–chest pain symptoms need to be evaluated.” I don’t see how that can be done if they follow no discernable (sic) pattern. But you must be patient and wait for the Yale VIRGO study, if you want to know everything that can be known about the presentation of MI in younger women.
Intensive Glucose Regulation in Hyperglycemic ACS (pg. 1896): The Less is More article this week provides one more piece of evidence that when patients coming into hospital with acute coronary syndrome have hyperglycaemia, you do more harm than good if you try to control their sugar within tight limits. Many previous studies (which I haven’t commented on) have shown this, and here it is demonstrated in a single-centre, prospective, open-label, randomized clinical trial in a large teaching hospital.
Lancet 16 Nov 2013 Vol 382
Intra-aortic balloon counterpulsation in acute myocardial infarction complicated by cardiogenic shock (IABP-SHOCK II) (pg. 1638): Here is a paper which has got into The Lancet but would have been equally at home in JAMA Intern Med‘s excellent Less is More series. The German IABP-SHOCK II trial recruited patients with cardiogenic shock complicating acute myocardial infarction, who were undergoing early revascularisation and receiving optimum medical therapy. Half of them were randomized to receive intra-aortic balloon pump (IABP) circulatory support. This gave cardiologists something to do while these very sick patients either died or survived, but it did not make any difference to 30-day mortality. This study confirms that there was no all-cause mortality benefit at 12 months either.