Richard Lehman’s journal review—25 November 2013

Richard LehmanNEJM  21 Nov 2013  Vol 369
1981   “The 2011 outbreak in China showed that poliomyelitis-free countries remain at risk for outbreaks while the poliovirus circulates anywhere in the world. Global eradication of poliomyelitis will benefit all countries, even those that are currently free of poliomyelitis.” So concludes a study of the said Chinese outbreak, which was halted with the use of 44 million doses of vaccine. There are few sadder things to contemplate than the current impasse in global polio eradication. It seems quite incredible that religious murderers in Pakistan can regard the killing of health workers and the paralysis and death of children as commendable in the sight of their god. And that the world can do nothing about it.

1991   Time for another go at understanding vitamin D metabolism. Are you sitting comfortably? Well you won’t be for much longer. Try chewing on this: “Community-dwelling black Americans, as compared with whites, had low levels of total 25-hydroxyvitamin D and vitamin D–binding protein, resulting in similar concentrations of estimated bioavailable 25-hydroxyvitamin D. Racial differences in the prevalence of common genetic polymorphisms provide a likely explanation for this observation.” So what then is the role of vitamin D-binding protein? If the first sentence is correct, it must be to render vitamin D bio-unavailable. It mops up 85-90% of circulating vitamin D, and it seems a very odd protein for human beings to be equipped with. The text of the paper says it acts as a vitamin D carrier, but where it carries the vitamin is unclear, since “the bound fraction may be unavailable to act on target cells.” This just sounds like a bad idea. I prefer nice albumin, which carries vitamin D to where it’s needed in a perfectly straightforward way.

2001   Last week I failed to point out a brilliant BMJ editorial by John Ioannidis about why dietary research is largely rubbish. “Nutritional intake is notoriously difficult to capture with the questionnaire methods used by most studies. A recent analysis showed that in the National Health and Nutrition Examination Survey, an otherwise superb study, for two thirds of the participants the energy intake measures inferred from the questionnaire are incompatible with life.” Sounds nuts to me. And now, ah, what do we have in this new study: “Dietary intake was measured with the use of validated food-frequency questionnaires administered every 2 to 4 years. In the 1980 and 1984 dietary questionnaires, we asked the participants how often they had consumed a serving of nuts.” This study was not from NHANES but from a combination of the (female) Nurses’ Health Study and the (male) Health Professionals Follow-up Study. They went on studying nut consumption in diaries of ever-increasing sophistication, so they must be true. Well, perhaps. And so to the conclusion: “the frequency of nut consumption was inversely associated with total and cause-specific mortality, independently of other predictors of death.” Now in my view it would be nuts to assume this relationship is causal; and also nuts to eat anything for any reason but the fact that you are hungry and enjoy it.

JAMA  20 Nov 2013  Vol 310
2050   Fat people get atrial fibrillation more than thin people, which is one reason cited by researchers in Adelaide as a reason they decided to study the effect of weight loss in people with AF and a body mass index of 27 or over. They cite a host of other reasons: “Obesity has been associated with diastolic dysfunction, a systemic proinflammatory state, autonomic tone abnormalities, and atrial enlargement—changes known to promote arrhythmogenesis. In addition, fat stores have been shown to correlate with incident atrial fibrillation. A recent study has demonstrated a direct effect of obesity on the atrial substrates.” All quite terrifying to the adipose fibrillator, though I am not sure whether this makes any difference to their prognosis. The patients in this study were aged around 60 (much younger than the average for AF) and the researchers from Adelaide were fearsomely effective in achieving weight loss in the intervention group: a whole 14.3 kg over 15 months. These patients felt better and had lower symptom scores than the control group, who still managed a creditable 3.6kg weight loss. I don’t really know what this study tells us that we couldn’t have guessed about the short term, and of course only time can tell us about the rest.

Lancet  23 Nov 2013  Vol 382
1705   A tiny (n=30) commercial phase 2 trial takes pride of place in this week’s Lancet. “Secukinumab rapidly reduced clinical or biological signs of active ankylosing spondylitis and was well tolerated. It is the first targeted therapy that we know of that is an alternative to tumour necrosis factor inhibition to reach its primary endpoint in a phase 2 trial. Funding: Novartis.” Even the editorialist can’t find much to say about this drug except the usual stuff about a promising approach, further trials needed etc. So why does this paper take preference over the many papers of real clinical significance that the journal must be offered every week? It isn’t hard to guess; and it just shows how absurd the current commercial model for medical journals really is.

1714   The next article describes the results of a prospective study of just over 5,000 patients who underwent coronary stenting in Europe and the USA. As the stents were all drug-eluting, everybody received aspirin plus a thienopyridine (usually clopidogrel): this is called dual anti-platelet therapy or DAPT, and was meant to continue for 2 years. But over this period, more than half the cohort gave up DAPT at some point, usually continuing aspirin and dropping the thienopyridine. Now comes the analysis, and I defy anyone to summarise it simply. The take home message seems to be that after the first few weeks it seems to make remarkably little difference to restenosis rates whether or not you comply fully with DAPT, but it’s still just a bit safer to carry on if you can.

1723   “In this unblinded, randomised, controlled, parallel-group trial, pregnant women at two metropolitan teaching hospitals in Australia were randomly assigned to either caseload midwifery care or standard maternity care by a telephone-based computer randomisation service.” There were slightly fewer elective caesarian sections in the caseload group but otherwise clinical outcomes were exactly the same for the two models of care. So it really doesn’t matter which system you adopt except that in this particular context, the caseload model came out cheaper.

BMJ  23 Nov 2013  Vol 347
If elderly people have falls, it is usually because they are walking abnormally, or trip over something—that was the conclusion of a video surveillance study in a nursing home a few years ago. Strange that it came as something of a surprise. And this systematic review of  exercise programmes to prevent falls shows that exercise really does reduce the rate of falls and the rate of major injuries. Common sense is often true. No more studies of exercise for falls, please. We know the answer.

What a difference a day makes. On Saturday I was in the audience amongst the good and the great and the definitely-not-so-good at the Saïd Business School in Oxford, discussing Big Change in Global Health. New devices, social media, fast-throughput procedures, workforce change, big markets needing new kinds of thinking and penetration. On Sunday I did my usual seven hour shift in the emergency primary care centre covering a wide area of North Oxfordshire and adjacent Northamptonshire with three GPs in the morning and two after midday. It is just about possible to do this provided there is no major end-of-life or mental health emergency to tie down a doctor for an hour or two in some remote rural location. And yesterday was perfectly OK—patients every 15 minutes, antibiotics handed out fairly freely, in a way that might have rankled with Dame Sally Davies had she come here from the conference; people who were often fat, which would have annoyed her even more; and elderly people with conditions like heart failure, who “block beds” and are “frequent flyers” and contribute to the “problem of readmission.” Here they are just sick people in the throes of a particularly awful mode of dying, scared, weak, and exhausted. But you have to apologise as you send them to hospital, just because you know that two GPs covering hundreds of square miles and a nurse who works till 9 pm are not going to be able to manage them at home. And then there is dementia. Every dementing person who remains at home does so through the heroism of another person or persons. And the support such people get during the week often disappears at weekends too. I went out to see a man with dementia whose wife had been looking after him as he got up and down all night with a urinary tract infection. She was exhausted. I told her not to be brave and old-fashioned, but call for help if the antibiotics didn’t work quickly. We had a hug. No doubt this was a waste of resources and should have been dealt with by telemedicine.

Ah—why am I telling you all this? It’s because a British trial has just shown that, “A manual based coping strategy was effective in reducing affective symptoms and case level depression in carers of family members with dementia. The carers’ quality of life also improved.” The manual referred to was not a squeeze of the hand, but an instruction manual. It haunts me that the lives of these people in 21st century England are so awful that even such a simple intervention can make such a difference.

Ann Intern Med  19 Nov 2013  Vol 159
649   Funny how some words get people reading. “Arsenic” was one of Agatha Christie’s favourites, and in England at any rate it is hard to think of arsenic without Old Lace. The website of Annals this week features a blackboard with As written in red and surrounded by its atomic properties. And that’s about as good as it gets. The actual study featuring arsenic consists of a single measurement of inorganic and methylated arsenic species in urine at baseline in a cohort of Native Americans, compared with their incidence of cardiovascular disease in subsequent years. That’s it. There might be some association, but the more you adjust for confounding factors, the less it gets. Next: Old Lace.

660   The closest I ever come to being involved with percutaneous coronary intervention is when I see patients with nasty femoral haematomas following the procedure. This study looks at 85 048 PCIs done in Michigan from 2007 to 2009. It would be interesting to know how many of them were really needed, but that’s not the point of this study. Just over a third of these patients had a vascular closure device placed over the site of femoral puncture, and these patients had fewer complications and fewer transfusions. If you’re an interventional cardiologist, read on for the subgroup effects, etc.

688   Nine systematic reviewers trawl through the literature to see if there is any evidence to support the FDA’s warning about possible cognitive impairment due to statins. There is not: all the evidence is less than first rate, but none of it supports an association. In particular, “Examination of the FDA postmarketing surveillance databases revealed a low reporting rate for cognitive-related adverse events with statins that was similar to the rates seen with other commonly prescribed cardiovascular medications.” I have no idea why people are currently going to such lengths to suggest that statins have hidden harms and should not be “overprescribed.” Personally I can’t see any reason why anybody should be worried about taking a statin if they so wish, but that may be because I am really a rare example of statin-related cognitive impairment.

Plant of the Week: Nerine bowdenii

This a shockingly gay flower to be seen in November: bright pink recurved blooms riot from upright stems amidst the mud and the shored up leaves of late autumn.

I love to see them in other people’s gardens but I’ve never really been able to decide on where to put them in our small patches. They are really in the worst of all possible taste, so I badly want to grow them, and yet I can’t think of a good place for them to shout from. This calls for an experiment, but it is probably too late for this year.

The best nerines I have seen this year were in the front garden of a red brick bungalow, in long proud rows. They clearly gave joy to their owner, perhaps because from inside the house you didn’t have to see them against the brick.