April 2nd, 2012
Selections from Richard Lehman’s Literature Review: Week of April 2nd
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.
Week of April 2nd
JAMA 28 Mar 2012 Vol 307
Sinners in the Hands of Angry Heart Disease (pg. 1273): Look into your hearts, my brothers and sisters! How few of you are saved from the perdition of cardiovascular risk! Just 1.2% of Americans can count themselves truly upright, by not smoking; being physically active; having normal blood pressure, blood glucose and total cholesterol levels, and weight; and eating a healthy diet. The rest are mired in sin – by genetic predestination or moral turpitude; and the world grows ever less righteous. According to the John Calvin of epidemiology, the late Geoffrey Rose, cardiovascular disease should have doubled since 1992, when he published his book The Strategy of Preventive Medicine. Instead it has halved. How depressing it must be for the Calvinists when so many sinners fail to die.
Cardiovascular Risk in Statin-Treated Patients (pg. 1302): One reason that so many sinners survive is the widespread use of statins in high-risk patients. Wistful for the enormous profits that these drugs brought in during the last two decades, pharma companies continue to search for a lipid-lowering drug which will add to the effect of HMG co-reductase inhibition. So what is the lipid subfraction that most predicts risk in people taking statins? Here’s a painstaking individual patient data meta-analysis showing that it is not low-density lipoprotein cholesterol alone, nor apolipoprotein B, but the totality of non-high-density lipoprotein cholesterol. Lower this, and you may have the next lipid-lowering blockbuster; or you may have nothing; or you may kill people.
NEJM 29 Mar 2012 Vol 366
Mobility in Type II Diabetes (pg. 1209): I have written a lot about patient-important outcomes in type 2 diabetes, but one that we can easily overlook is mobility. In obese people with T2DM, loss of mobility leads to a downward spiral of diminished energy loss, muscle atrophy and increase in adiposity: worsening glycaemic control then leads to all the problems of insulin therapy in people who cannot exercise and are insulin resistant. We have all seen this happen to our patients, and it is likely to become a commoner sight throughout the world unless we can find an effective intensive lifestyle intervention – one that can be applied to millions of individuals. The Look AHEAD trial enrolled more than 5,000 patients and achieved a 40% reduction in loss of mobility over 4 years in its intensive intervention arm. This could be of generalizable importance. Methodology buffs will also be impressed with the sophistication of the analysis: “We used hidden Markov models to characterize disability states and mixed-effects ordinal logistic regression to estimate the probability of functional decline.” A worthwhile paper.
Lancet 31 Mar 2012 Vol 379
Interleukin-6 Receptor Signalling and Cardiovascular Disease (pg. 1205): The Higher Calvinism of cardiology is a terrifying religious system of predestination by genomics. Someone needs to write a satirical novel about it, like James Hogg’s grim tale of Scottish Calvinism gone mad in Private Memoirs and Confessions of a Justified Sinner (1824). The latest focus of genomic theology is interleukin-6 receptor (IL6R) signalling, one of the many ways by which the wrathful gene-god dooms the unworthy to suffer cardiovascular disease. Never mind that we know many other important ways, and that this one is just an aspect of general inflammation. The Church of Genomics demands that we must not pit our humble understanding against a list of authors and investigators which covers two pages of small print. The entire priesthood proclaim that by analysing 82 studies, they can affirm that “large-scale human genetic and biomarker data are consistent with a causal association between IL6R-related pathways and coronary heart disease.” Aye, consistent with. What more can the faithful believer require?
BMJ 31 Mar 2012 Vol 344
Promoting exercise: Encouraging physical activity in sedentary patients is undoubtedly a worthwhile endeavour, but that does not mean we know how to do it effectively. A bit of exhortation now and again is unlikely to work, so the temptation is to refer patients elsewhere, and I have certainly written out lots of exercise prescriptions to local gyms. Unfortunately we don’t really know if this tactic works either. This systematic review from the Cambridge primary care department reaches a rather downbeat conclusion.