Richard Lehman’s journal review—18 April 2016

richard_lehmanNEJM 14 April 2016 Vol 374

Fixing spinal stenosis
1413 Magnetic resonance imaging was like magic when it first appeared. Suddenly structures in the back that could only be guessed at on x-rays or even CT scans could be seen in lavish detail. It became clear that there was no such thing as a normal back: discs bulged here and degenerated there, narrowed nerve foramina abounded, and vertebrae showed slippage in many wanton and disturbing ways. For millions of patients with back pain, plausible explanations could be demonstrated on the screen and treated with expensive new operations and devices. Just to give a keynote lecture about one of these could earn an orthopaedic surgeon $1 million from a manufacturer less than 20 years ago. For lumbar spinal stenosis, simple decompression operations were rapidly overtaken in the US by combined procedures of decompression and fusion, which increased by a factor of 15 between 2002 and 2007. Two publicly funded trials in this week’s NEJM may mark the end of the party, surely one of the most extravagant even in the history of American medicine. From cool Sweden comes a trial in 247 patients between 50 and 80 years of age who had lumbar spinal stenosis at one or two adjacent vertebral levels. They were randomized to undergo either decompression surgery plus fusion surgery, or decompression surgery alone. The combined procedure cost more but did not result in better outcomes at two or five years’ follow-up.

A rod for your back
1424 The second trial, from the USA, recruited only patients with spondylolisthesis, i.e. slippage of adjacent vertebrae, where you would think that rod fixation would be likely to improve outcomes. Sixty-six patients with symptomatic grade 1 spondylolisthesis were assigned to lumbar spinal fusion using rigid pedicle screws affixed to titanium alloy rods in addition to decompressive laminectomy, or to laminectomy alone. There was only a slight difference in quality of life at two years in favour of the fusion group. These trials are discussed in a useful editorial. It does not provide much support for the idea that the many billions of dollars spent in the USA on spinal fixation devices have been well spent.

Mitral fix adds nothing to CABG
OL So Less is More in back surgery, which comes as no great surprise. What about cardiac surgery? A fair proportion of ischaemic heart disease is accompanied by mitral regurgitation, so perhaps if you are opening up the chest to bypass the coronary arteries you might as well tighten up the mitral valve while you’re in there. A Canadian trial randomly assigned 301 patients to undergo either CABG alone or the combined procedure. Although the mitral valve repair worked on echo follow-up, it conferred no extra functional or mortality benefit at two years, and had a higher rate of immediate complications.

TAVR the wonder valve
OL When it comes to the aortic valve, there is a tendency now not to open the chest at all, but to use a balloon-expandable replacement valve implanted via a catheter. Although I may have been less than generous in my remarks about interventional cardiologists at certain times, I must repeat my unqualified admiration of those who can perform this feat. It was first used as a last-ditch procedure in those too poorly to have “proper” aortic valve replacement via a gash in the heart. Now it is poised to take over the “intermediate risk” population, thanks to the various PARTNER trials of the SAPIEN-XT device, designed and funded by Edwards Lifesciences. I won’t try and walk you through their differing populations and the nuances in the reporting of their results—there is a whole paper on The Lancet website doing that. I will quote the NEJM report at face value and tell you that “TAVR, performed in experienced centers, with the use of a lower-profile, next-generation device, was noninferior to surgery with respect to outcomes at two years (death from any cause or disabling stroke)… several benefits with regard to secondary end points were associated with TAVR, including lower risks of bleeding events, acute kidney injury, and new-onset atrial fibrillation, as well as more rapid early recovery that resulted in shorter durations of stay in the ICU and hospital.”

Cabbage with your HF pills, sir?
OL So cardiology is changing. There is less of it than there used to be. What is left to be done is often done through veins rather than sternotomies. But heart failure will continue to be a common mode of death, though ever less of it will be due to “ischemic cardiomyopathy.” This is a popular current term in America for any kind of HF accompanying ischaemic heart disease and a reduced left systolic ejection fraction. I wish cardiologists had kept it for a different subset with microangiopathy and diffuse remodelling, but never mind. There is no mending the unhelpful terminology of “heart failure”. In the STICH trial they selected 1212 patients with coronary artery disease that was amenable to CABG and an ejection fraction of 35% or lower. They were randomized to medical treatment or to CABG plus medical treatment. “Overall, CABG was associated with an incremental median survival benefit of nearly 18 months and prevention of one death due to any cause for every 14 patients treated and of one death due to a cardiovascular cause for every 11 patients treated.” This is one way of presenting the results, which for all-cause mortality just crossed the border of significance. Another is this: “A primary outcome event (death from any cause) occurred in 359 of 610 patients (58.9%) in the CABG group and in 398 of 602 patients (66.1%) in the medical-therapy group (hazard ratio with CABG vs. medical therapy, 0.84; 95% confidence interval [CI], 0.73 to 0.97; P=0.02 by log-rank test).” Now I’d really like some of you who are smarter than I am at such things to work out how you can honestly and succinctly convey the results of this trial so that they make decision making easy (a) for doctors, who need to understand what they are doing, and (b) for patients, who need to understand what they are letting themselves in for. I think it has to be that way round for practical reasons. Hint: use several infographic methods. I long for the time when understandable visual displays will be a standard part of reporting every interventional trial.

JAMA 12 April 2016 Vol 315

New uses for dexmedetomidine?
1460 The effectiveness of dexmedetomidine when added to standard care in patients with agitated delirium receiving mechanical ventilation is not a subject on which I have anything interesting to say. As in previous ICU studies, this drug proved useful. But now that I’ve had my attention drawn to dexmedetomidine, I wonder if it might have uses in palliative care which have not been fully explored. It is an intravenous α-2 agonist with analgesic and anti-delirium effects and a lack of respiratory suppression. It might be a helpful adjunctive treatment for dying patients who are distressed and hypoxaemic, e.g. due to end-stage lung or heart disease. Doing a quick Medline search, I can’t see any literature about this. We so much need a wider choice of agents to help people who are breathless and dying.

JAMA Intern Med April 2016 Vol 176

Funereal presumptions
OL Aha! A qualitative study in a leading general medical journal. It explores the views of 26 doctors and 2 nurse practitioners in American primary care about assessing and discussing prognosis with patients. “Participants often considered prognosis without explicitly discussing it with patients and disagreed on whether and when long-term prognosis needs to be specifically discussed. The participants identified numerous barriers to incorporating prognosis in the care of older adults including uncertainty in predicting prognosis, difficulty in discussing prognosis, and concern about patient reactions.” I think that’s just as it should be. There are times when one has to break bad news, or express uncertainty about something that may have serious consequences. But discretion is often the better part of valour, and it is not cowardice to err on the side of caution and to let time be a helper. The commentary on this study is titled “Discussing Long-term Prognosis in Primary Care: Hard but Necessary.” I would put a “sometimes” before the necessary. And always bear in mind that we are for the most part extremely bad at long-term prognostication.

Lancet 16 April 2016 Vol 387
Pushing more opioids
1644 For several centuries, opiates—meaning real derivatives of the opium poppy—could be bought freely in most towns and cities of Europe. I think the British are much to blame for tarnishing the reputation of opium, first through its romanticised abuse by Coleridge and de Quincey in the first decades of the nineteenth century, and then through the outrageous Opium Wars of the 1840s and 1850s in which Britain aimed to render China a nation of hopeless addicts. As a result, opioids have come under intense restriction in many countries, even for the relief of severe acute pain, while tobacco, which is more addictive and far more harmful, is openly sold everywhere. The underuse of medical opioids is causing millions of people around the world avoidable distress, particularly at the end of life. In one of the big global surveys that are the best aspect of The Lancet, we learn that from 2001 to 2013, use of opioid analgesics has increased, but remains low in Africa, Asia, Central America, the Caribbean, South America, and eastern and southeastern Europe. “The barriers to opioid medicine use include absence of prescriber training, fear of producing dependence on opioid analgesics, financial constraints, and problems sourcing or importing opioid medicines. Cultural attitudes toward pain management, fear of diversion, and fear of criminal prosecution were also frequent impediments.” I realize of course that the overuse of long-term prescribed opioids is a major problem in North America and causes many unintentional deaths. But globally, the problem is the other way round.

Delayed stenting for STEMI
OL I find it hard to believe that when I first started writing these reviews 18 years ago, “stent” was a new word, and if you had said “troponin” you would have met with a blank stare. Myocardial infarction was diagnosed by ECG and “cardiac enzymes” and treated with thrombolysis, usually still with streptokinase. In the early 2000s the scene changed with amazing rapidity. Within a few years, services were reconfigured to try and achieve immediate percutaneous intervention for everyone, and drug-eluting stents took over as the new standard treatment. For a mere generalist bystander who tried to follow the studies as they appeared, it was a confusing time. It still is. Clearly we are doing some things better than in 1998, but just when should we be doing what, and for what marginal benefit? A Danish trial decided to see whether stents for STEMI are best placed immediately (i.e. at the time of emergency PCI), or as a separate procedure 48 hrs later. At a median follow-up of 42 months, there was no difference between outcomes in the two groups of 600+ patients each.

BMJ 16 April 2016 Vol 353

Class & mortality in bits of Europe
Being of a somewhat Marmottian disposition, I’m quite interested in how social inequality affects mortality across Europe, and how that has changed over two decades. But a Dutch study that attempts to do this leaves me a bit fazed. I haven’t ever visited Turin or Barcelona, but I wouldn’t be inclined to take either as typical of “Italy” or “Spain.” Why, it is even rumoured that cars stop at red lights in Turin, and that Barcelona considers itself in a different country from Spain. Countries that I would judge to be substantial parts of Europe, such as Greece, Germany, Poland, Sweden and Hungary are altogether absent, as are several others. My conclusion has to be that we don’t really know what is happening to mortality inequality in most of Europe. In the bits that happen to record it, it seems mostly to be diminishing.

Saturated fat for healthy hearts
This rework through the data from the Minnesota Coronary Experiment (MCE) of 1968-73 has had a lot of publicity, but that still didn’t spare me a feeling of shock on reading the actual paper. 9423 people confined to one nursing home and six state mental hospitals in Minnesota were randomized to a diet that replaced saturated fat with linoleic acid (from corn oil and corn oil polyunsaturated margarine), or a control diet high in saturated fat from animal fats, common margarines, and shortenings. The intervention group had significant reduction in serum cholesterol compared with controls (mean change from baseline −13.8% v −1.0%; P<0.001). There was a 22% higher risk of death for each 30 mg/dL (0.78 mmol/L) reduction in serum cholesterol in covariate adjusted Cox regression models. There was no evidence of benefit in the intervention group for coronary atherosclerosis or myocardial infarcts. So this was clear, randomized evidence on the true effect of imposed dietary change, showing that it is harmful to restrict the intake of saturated fats. It was followed by decades of zealous dietary preaching that ran directly contrary to its findings. In the end there is only one useful piece of dietary advice: eat fruit. Then eat whatever else you like. Unless you are allergic to it.

Plant of the Week: Sanguinara canadensis “Flore pleno”

I can’t help mentioning this little wonder each time it appears. There is one week each year when it literally outshines everything else in the garden. There is no white quite as white as the flower of the Canadian bloodroot. In the double form, its petals radiate pure light like an outspread star a few centimetres above the soil. Then it is gone. Its pretty frilled leaves feed the dark rhizome beneath to produce more flowers the next year. Once that is big enough, you can split it for friends in the autumn, preferably with a child nearby to wonder at the blood-like sap that oozes from the cut.