In Favor Of Fever by Robin Hanson‏

The US spends over 17% of income, two trillion dollars a year, on medicine, mostly on new intensive treatments. You might think this was because we long ago carefully studied all the simple cheap treatments, and got as much mileage as we could from them, so now must consider complex expensive treatments. You’d be very very wrong.

One of the commonest, and cheapest, forms of medicine is “antipyretics”, e.g. aspirin, for reducing temperature. You know you are getting “modern” medicine if, when sick, people take your temperature often, and give you antipyretics when “too hot.” Seeing this care, you can relax assured you are getting modern care.

Turns out, we hardly have any data on whether this helps, and what data we do have says it probably makes you sicker, except in a few rare situations like stoke or head injury. It seems we are very reluctant to give up the appearance of helping the sick, even if our “help” probably makes them sicker.

We also seem pretty uninterested in collecting the data needed to clarify this. The biggest randomized trial to date was stopped mid-trial because “there were seven deaths in people getting standard treatment and only one in those allowed to have fever, … [so] it would be unethical to allow any more patients to get standard treatment.” Yet standard treatment continues because others say not enough trials exist to justify changing standard treatment. Is that #$@%-ed up ethics or what? Details:

One of the hallmarks of infectious illness, a fever is not just uncomfortable. In some cases it can trigger fits and perhaps even brain damage. The usual response is to bring down the temperature with antipyretic drugs, such as aspirin. … It has long been acknowledged that such drugs could, in theory, be counterproductive – they do, after all, interfere with the body’s natural response to infection. But these qualms have been set aside for a variety of reasons: the need to relieve discomfort; fears about brain damage; time-honoured practice; and, some would say, the urge to be doing something rather than nothing. ..

But now there’s growing concern that these time-honoured approaches are at best misguided and at worst potentially life-threatening. … the idea that antipyretics can prevent fits in children is looking increasingly shaky. …

“[Fever is] very old, existing not only in mammals and birds but also in fishes, amphibians and reptiles.” … It now seems that many disease-fighting mechanisms work better in hotter conditions. … It has also become clear that fevers are bad news for many microbes. … [Researchers] compared the quantity of bacteria in blood samples at normal body temperature with those at 40 °C and found that levels plunged by almost 90 per cent after several hours’ exposure to the higher temperature.

… How does that extrapolate to real-life patients? Unfortunately … The few existing studies are mainly “observational” ones. … Observational studies done in the 1980s and 90s did suggest that antipyretics hinder, rather than help the body’s response to the common cold, chicken pox and malaria. More recently, … examining over 400 records, Barlow’s team [found] the more feverish the patient on admission, the better their chance of survival. …

There has … been one randomised trial … in patients in intensive care … In 2005, [researchers] … studied 82 critically ill patients who did not have head injuries or other problems that make a high temperature risky. Patients were randomised to get either the standard treatment of antipyretics if their temperature went past 38.5 °C, or only receiving the drugs if their temperature reached 40 °C. As the trial progressed, there were seven deaths in people getting standard treatment and only one in those allowed to have fever. Although this difference was not quite large enough to be statistically significant, the team felt compelled to call a halt, feeling it would be unethical to allow any more patients to get standard treatment. …

Menon, however, believes there is not enough evidence yet to change practice. “It’s one study.” … He points out that there is plenty of evidence to show a raised temperature is harmful to the brain after a head injury or stroke. … Many patients in intensive care due to an infection are so ill … because of their body’s excessive response to [microbes] – of which fever is a part. … Even doctors like Menon, however, acknowledge that antipyretics are probably overused for minor illnesses. …

In 2007 … guidelines from the UK’s … NICE … [said] antipyretics should be used only if the fever seemed to be causing a child distress. … Febrile convulsions … almost never cause any lasting harm … [and] cannot be prevented by antipyretics. … “Not many people changed their practice. … We need to do a large randomised trial – it is the only way we can find out for sure.”

To check on this article, I did a quick search for randomized trials of antipyretics. I found this, this, this, and this; none found a significant health benefit from antipyretics.

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