Posts filed under Medical news (156)

A round-up of some worthwhile links on Angelina Jolie and BRCA1

• Angelina Jolie. My Medical Choice
• Hilda Bastian (evidence-based medicine specialist and cartoonist) Keeping Health Risks in Perspective When the Dramatic and Rare Goes Culturally Viral
• Melanie Tannenbaum (social psychology) Why It Matters That Jolie Wrote About Her Medical Choice
• David Gorski (surgical oncologist and curmudgeon) Angelina Jolie, radical strategies for cancer prevention, and genetics denialism
• Gayle Sulik (medical sociologist) Angelina Jolie and the one percent
• Breast cancer screening in NZ. BRCA genetic testing is recommended and subsidized only for women with a strong family history, and where possible should start by testing one of the affected relatives to make sure that the familial pattern is actually due to BRCA1 or BRCA2 mutations, not some other gene.
• What’s actually patented in the evil gene patent.  The most important part of patent covers the short ‘mirror-image’ DNA molecules needed by the current testing technology: it will be a race to see if sequencing-based tests make the patent obsolete before it expires in 2015 (or, potentially, is overturned by the US Supreme Court later this year).

As part of International Clinical Trials Day, the UK National Health Service is launching “It’s ok to ask”:

Clinical research is the way in which we improve treatments in the NHS. In many cases doctors will tell patients about research but we also need patients to ask about it and keep research at the top of the NHS agenda.

In a recent consumer poll, only 21% of patients and the public said that they would feel confident asking their doctor about research opportunities – a low number.

That is why during 2013/14 The National Institute for Health Research (NIHR) is promoting the fact that it’s OK to ask about clinical research.

The campaign is aimed at patients, medical professionals and the public. Everyone can get involved and help spread the word that it’s OK to ask about clinical research.

The campaign is in the UK, but it’s ok to ask in NZ too.

Two hundred and sixty six years ago today, James Lind began what is regarded as the first proper controlled clinical trial

On the 20th May, 1747, I took twelve patients in the scurvy on board the Salisbury at sea. Their cases were as similar as I could have them. They all in general had putrid gums, the spots and lassitude, with weakness of their knees. They lay together in one place, being a proper apartment for the sick in the fore-hold; and had one diet in common to all, viz., water gruel sweetened with sugar in the morning; fresh mutton broth often times for dinner; at other times puddings, boiled biscuit with sugar etc.; and for supper barley, raisins, rice and currants, sago and wine, or the like. Two of these were ordered each a quart of cyder a day. Two others took twenty five gutts of elixir vitriol three times a day upon an empty stomach, using a gargle strongly acidulated with it for their mouths. Two others took two spoonfuls of vinegar three times a day upon an empty stomach, having their gruels and their other food well acidulated with it, as also the gargle for the mouth. Two of the worst patients, with the tendons in the ham rigid (a symptom none the rest had) were put under a course of sea water. Of this they drank half a pint every day and sometimes more or less as it operated by way of gentle physic. Two others had each two oranges and one lemon given them every day. These they eat with greediness at different times upon an empty stomach. They continued but six days under this course, having consumed the quantity that could be spared. The two remaining patients took the bigness of a nutmeg three times a day of an electuray recommended by an hospital surgeon made of garlic, mustard seed, rad. raphan., balsam of Peru and gum myrrh, using for common drink narley water well acidulated with tamarinds, by a decoction of wich, with the addition of cremor tartar, they were gently purged three or four times during the course.

The consequence was that the most sudden and visible good effects were perceived from the use of the oranges and lemons; one of those who had taken them being at the end of six days fit four duty. The spots were not indeed at that time quite off his body, nor his gums sound; but without any other medicine than a gargarism or elixir of vitriol he became quite healthy before we came into Plymouth, which was on the 16th June. The other was the best recovered of any in his condition, and being now deemed pretty well was appointed nurse to the rest of the sick …

Lind knew very little about scurvy apart from the typical progress of the disease, and he had no real idea of how the treatments might work.  That’s a handicap in coming up with ideas for treatment, but not in doing fair tests of whether treatments work.

The trial didn’t have an untreated group: all the patients got one of the treatments recommended by experts.  There’s no need for a controlled trial to have an untreated group — if there is an existing treatment, you want to compare to that treatment; if there is none, you may want to compare immediate vs delayed treatment.

Despite the dramatic success of fruit juice in the trial, it wasn’t adopted as a treatment. That, sadly, can still be the case today.  New drugs or surgical techniques are taken up enthusiastically, but boring interventions like nurse home visits or surgery checklists get less attention. Still, things are much better than they were even twenty years ago. Nearly all of medicine accepts the idea of randomized controlled comparison, and it is spreading to other areas such as development economics.

There are two excellent, free books about clinical trials and health choices: Testing Treatments, from the James Lind Initiative, and Smart Health Choices, from Les Irwig (at Sydney Uni) and coworkers.

Much of clinical trials development is unapologetically technical, but there are important areas where public participation can help:

• The James Lind Alliance asks patients and clinicians to say what questions matter most.  Clinical trials still tend to answer questions that are scientifically interesting or commercially important, not what actually matters most to patients
• The Cochrane Collaboration is attempting to collect and summarise all randomized trials.  The Cochrane Consumers Network is for non-specialist participation — in particular as Consumer Referees to help ensure that summaries of research address the questions that are important to consumers and are presented in language that consumers can understand.
• Ethics Committees that review clinical trials and other human research in New Zealand are required to have non-specialist community members. This is a substantial commitment, but one that is important if ethics committees are to be more than just red tape.
• And if you haven’t yet signed the AllTrials petition, calling for the results of all clinical trials to be published so we can know what treatments work, now would be an excellent time.

From the Wellcome Trust Monitor, a survey examining knowledge and attitudes related to biomedical science in the UK

The survey found a high level of interest in medical research among the public – more than seven in ten adults (75 per cent) and nearly six out of ten of young people (58 per cent). Despite this, understanding of how research is conducted is not deep – and levels of understanding have fallen since 2009. While most adults (67 per cent) and half of all young people (50 per cent) recognise the concept of a controlled experiment in science, most cannot articulate why this process is effective.

Two-thirds of the adults that were questioned trusted medical practitioners and university scientists to give them accurate information about medical research. This fell to just over one in ten (12 per cent) for government departments and ministers. Journalists scored lowest on trustworthiness — only 8 per cent of adults trusted them to give accurate information about medical research, although this was an improvement on the 2009 figure of 4 per cent.

I’ve got no objection to speculative or controversial research being in the media, as long as it’s marked as such, which it often isn’t.

In September, the Herald told us researchers were finding that dementia was due to high blood sugar, essentially a diet and exercise problem.

Today we learn that it’s actually ‘technology’ that causes dementia, in a, like, totally interconnected way

“Considering the changes over the last 30 years – the explosion in electronic devices, rises in background non-ionising radiation – PCs, microwaves, TVs, mobile phones; road and air transport up four-fold increasing background petro-chemical pollution; chemical additives to food, et cetera,” Professor Pritchard said.

“There is no one factor rather the likely interaction between all these environmental triggers, reflecting changes in other conditions.”

What actual research paper found is that the ratio of  diagnoses of neurological diseases  to deaths had risen, across 16 countries, indicating that people live longer after diagnosis.  This could be due to earlier onset, the explanation Prof. Pritchard gives, but they actually don’t do any correction for changes in diagnosis.  Earlier diagnosis could just mean earlier diagnosis, not earlier onset of disease.  Changes in how deaths are classified could also have played a part, although these are less likely to be consistent across countries.

The research paper makes a lot of the fact that dementia in women increased later than in men, attributing this to women entering the workforce and getting exposed to more scary modern stuff (without any actual data on the relative exposure to modern stuff in the workplace and at home).  Surely another possible explanation is that in the modern world, loss of memory and cognitive function is taken seriously in elderly women, but that 30 years ago it just wasn’t regarded as a medical problem.

The Herald has a completely over-the-top presentation of what might be an important issue. The headline is “Hospital choice key to kids’ survival”, and the story starts off

Where ambulances take badly injured children first seems to affect their chances, paediatric surgeons say.

Starship children’s hospital surgeons have found that sending badly injured children to the wrong hospital may be contributing to a child death rate from injuries that is twice the rate of Australia’s.

The data:

Six (7 per cent) of the 88 children who went first to Middlemore died, but so did one (8 per cent) of the 12 who went directly to Starship.

That is, to the extent the data tell us anything, the evidence is against the headline.  Of course, the uncertainties are huge: a 95% confidence interval for the relative odds of dying after being sent to Middlemore goes from a 40-fold decrease to a 12-fold increase.  There’s basically no information in the survival data.

So, how much of the two-fold higher rate of death in NZ compared to Australia could reasonably be explained by suboptimal hospital choice? One of the surgeons involved in the study says

… overseas research showed that a good trauma protocol system could cut the death rate for injured adults by 20 to 30 per cent, but there was no good data for children.

That is, hardly any of the difference between NZ and Australia — especially as this specific hospital-choice issue only applies to one sector of one city in New Zealand, with less than 10% of the national population.

On the other hand, we see

The head of Starship’s emergency department, Dr Mike Shepherd, said the major factors contributing to New Zealand’s high fatal injury rate for children lay outside the hospital system in policies such as driver blood-alcohol limits, graduated driver licensing, and laws requiring children’s booster seats and swimming pool fences.

That sounds plausible, but if it’s the whole story you would expect high levels of non-fatal as well as fatal injuries. The overall rate of hospitalisations for injuries in children 0-14 years is almost identical in NZ (1395 per 100 000 per year, p29) and Australia (‘about’ 1500 per 100 000 per year, page v).

Headline:  Study: Dark chocolate calms you down

Lead:

Eating dark chocolate can calm you down according to a new study.

Number of people actually given dark chocolate in the study: 0  (more…)

• From Felix Salmon: US population is increasing, and people are moving to the cities, so why is (sufficiently fine-scale) population density going down? Because rich people take up more space and fight for stricter zoning.  You’ve heard of NIMBYs, but perhaps not of BANANAs
• From the New York Times.  One of the big credit-rating companies is no longer using debts referred for collection as an indicator, as long as they end up paid.  This isn’t a new spark of moral feeling, it’s just for better prediction.
• And from Felix Salmon again: Firstly, Americans are bad at statistics. When it comes to breast cancer, they massively overestimate the probability that early diagnosis and treatment will lead to a cure, while they also massively underestimate the probability that an undetected cancer will turn out to be harmless.

Stuff has a story  (borrowed from the West Island) headlined “Over 40? Five tests you need right now”.

You might have expected some reference to the other recent news about screening: that the US Preventive Services Taskforce has now joined the Centers for Disease Control in recommending universal screening for HIV (as TVNZ reported).  It’s not clear if New Zealand will follow the trend — HIV infection in people not in high risk groups is less common here than in the US, so the benefit compared to more selective screening is smaller here.   This illustrates the complexities of population screening.  Not only does the test have to be accurate, especially in terms of its false positive rate, but there needs to be something useful you can do about a positive result, and screening everyone has to be better than just screening selected people.

So, let’s  compare the suggestions from Stuff’s story to what national and international expert guidelines say you need.

Two of the tests, for high blood pressure and high cholesterol, are spot on. These are part of the national 2012/13 Health Targets for DHBs, with the goal being 75% of the eligible population having the tests within a five-year period.  The Health Target also includes blood glucose measurement to diagnose diabetes, which the story doesn’t mention.  The US Preventive Services Taskforce also recommends blood pressure and cholesterol tests, though it recommends universal diabetes screening only after age 50 or in people with high blood pressure or people with risk factors for diabetes.

One of the tests recommended in the story is a depression/anxiety questionnaire, for diagnosing suicide risk.  Just a couple of weeks ago, the US Preventive Services Taskforce issued guidelines on universal screening for suicide prevention by GPs, saying that there wasn’t good enough evidence to recommend either for or against. As the coverage from Reuters explains, these questionnaires do probably identify people at higher risk of suicide, but it wasn’t clear how much benefit came from identifying them. So, that’s not an unreasonable test to recommend, but it would have been better to indicate that it was controversial.

One more of the tests isn’t a screening test at all — the story recommends that you make sure you know what a standard drink of alcohol is.

The top recommendation in the story, though, is coronary calcium screening.  The US Preventive Services Taskforce recommends against coronary calcium screening for people at low risk of heart disease and says there isn’t enough evidence to recommending for or against in people at higher risk for other reasons. The  American Heart Association also recommends against routine coronary calcium screening (they say it might be useful as a tiebreaker in people known to be at intermediate risk of heart disease based on other factors).  No-one doubts that calcium in the walls of your coronary arteries is predictive of heart disease, but people with high levels of coronary calcium tend to also be overweight or smokers, or have high blood pressure or high cholesterol or diabetes — and if they don’t have these other risk factors  it’s not clear that anything can be done to help them.

As an afterthought on the coronary calcium screening point, the story has an additional quote from a doctor recommending coronary angiography before starting a serious exercise program.  I’d never heard of coronary angiography as a general screening recommendation — it’s a bit more invasive and higher-risk than most population screening. It turns out that the American College of Cardiology and the American Heart Association are similarly unenthusiastic, with their guidelines on use specifically recommending against angiography for screening of people without symptoms of coronary artery disease.

While distracted by a conference in late January, I missed the next exciting installment of the Edinburgh pomegranate saga.

As you will recall, a research group in Edinburgh have put out press releases in recent years about the impact of pomegranate juice on blood pressure, cortisol (a stress hormone), and testosterone.  They haven’t published any scientific papers about these findings, though they have produced a presentation at a scientific conference.

The most recent installment claims that pomegranate extract reduces hunger and food consumption. This study seems to be better designed than the previous ones: participants were randomised to pomegranate extract tablets or placebo for three weeks.  They were then given a glass of pomegranate juice and a meal.  Those who had been taking the pomegranate extract reported feeling less hungry and ate less — 22% less. It’s a pity the study didn’t measure weight, because if the 22% reduction in food consumption generalised beyond the one experimental meal it would have led to measurable weight loss over three weeks.

Again, this was a premature and unsubstantiated press release, and the experiment has not been published in a peer-reviewed journal, although the researchers do at least say they will be presenting it at a conference later in the year.