This week's journal reviews on Doctors.net.uk
Journal Watch is a service provided to summarise some of the most popular medical journals.
Doctors.net.uk has a panel of specialist advisers responsible for reviewing a range of journals of general medical interest and some more specialised publications.
General Journal Watch is written by Dr Druin Burch, Consultant in Internal Medicine
This week's journals include...
The urgency of vitamin D tests
Vitamin D seems an increasingly likely candidate for involvement in everything from multiple sclerosis to tuberculosis to general health. What this editorial points out is the rational way to respond to recognising it's a likely candidate. Testing is needed, and it's needed urgently, but it has to be the right kind. Testing the hypothesis that vitamin D matters is sane. Testing large numbers of people's vitamin D levels, without having a clue what the implications are, is bonkers. It's kind of depressing how easy doctors and patients find it getting these things muddled.
The harms and benefits of screening mammography
We don't know the full balance of risks for screening mammography because it was never subject to a trial. The harms and benefits, therefore, can't be reliably known. This "stochastic simulation model" in a French population attempts what countless other papers have done before, namely to estimate these harms and benefits without doing such a trial. It thinks the harms weren't great but, because it isn't an RCT, it can't be sure. Endless other papers will continue to be published - although they shouldn't be - until someone screws up enough political courage to do a trial. Until that happens we should all admit that we're uncertain and choose whichever guess we fancy.
Marathon running takes its toll
Here's another study showing precisely what you knew it would. Marathon running has risks attached. If you're young you might drop down dead from hypertrophic cardiomyopathy, if you're old it may be from atherosclerotic heart disease, but your chance of not dropping down dead at all is huge. I can't see that this tells us anything useful whatsoever - for that we'd need to know what happened to these people if they were randomised to not running, and that's unknowable but quite likely to be not much different. What we need to know about marathon running, and can discover using the art of reflection rather than the pages of a Boston medical journal, is that it is tedious, time consuming and bad for our knees. Rowing and boxing, on the other hand, are activities of nobility and beauty. A devotion to marathon running is a marker of a defective character, and I'll not be argued into believing anything different.
Drinking water with meals
"We can lay down the definite and certain rule that it [water] should never be drunk at meals, and preferably not for at least one hour after the meal has been eaten. The effect of drinking water while eating is, first, to artificially moisten the food, thus hindering the normal and healthful flow of saliva and the other digestive juices; secondly, to dilute the various juices to an abnormal extent; and thirdly, to wash the food elements through the stomach and into the intestines before they have had time to become thoroughly liquefied and digested. The effects of this on the welfare of the whole organism can only be described as direful." Superb stuff, although this JAMA
opinion piece suggests it's a view that's now out-dated : Some water consumption with meals might be okay. Not that they wish their moderation to be taken to extremes - "nothing that has been said," they remark pointedly, "is intended to lend any support in the American custom of drinking water that is ice-cold." This piece from a hundred years ago makes you actively enjoy how mad the medical world can be - something that's helpful to keep in mind as you read through the rest of this week's journals.
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