What happens when we don’t publish clinical trials

The last blog I posted emphasised the importance of publishing all clinical trials. The story of Lorcainide is a stark warning of what happens when we don’t.

In 1980 a cardiologist in Nottingham named Alan Cowley carried out a small clinical trial of a drug called Lorcainide. It was known at the time that heart attacks could cause irregular heartbeats in patients (known as arrhythmia), and these arrhythmias often lead to early death. Lorcainide had been shown to suppress arrhythmia, so it made sense that patients who came to hospital with a heart attack should be treated with the drug. Cowley and his colleagues carried out a small trial with 95 patients, and tested them to see whether they were getting more or fewer arrhythmias. The drug worked, lowering the frequency of serious arrhythmia.

The doctors noticed something else however. Of the 48 patients on the drug, 9 had died, compared to only 1 patient on the placebo. This was a very small trial, so the doctors weren’t overly alarmed. It’s not surprising that 10 patients died in the study; these are patients who are presenting with heart attacks after all. It was just worrying that there was such an imbalance between the groups. The doctors chalked it up to bad luck, and viewed their trial as a success.

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Problems with clinical trials

Clinical trials are at the heart of our progress in medicine. If we have a new therapy, clinical trials tell us whether it is better than the current one. They measure outcomes, but also look out for side effects and unexpected consequences of taking the therapy. They are absolutely essential to our progress, and it is vital that they are carried out properly and transparently. Continue reading

Correlation vs Causation

The following headline caught my eye recently:

“Migraines could be caused by gut bacteria, study suggests”

The Guardian – 18/10/16

To anybody who suffers from migraines, this is very interesting; at the moment, we really don’t understand what causes them. If a study has figured this out, then we may be able to help the estimated 15% of the population who are sufferers.

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Trust in science

As with every other week, the last 10 days has brought a slew of tabloid stories, linking various things with causing or curing cancer:

GOOD: antacids, Chinese herbal remedy, berries and teaanthrax, frying food

BAD: being tall, tonsils, artificial football pitches, The RAF, oral sex

As always, these stories are largely nonsense, suitable only for the bin. Unfortunately, they are reported credulously and are widely read, and this saturation of health-related articles has several negative consequences.

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The reproducibility problem

The scientific process is an amazing thing. Between the Palaeolithic era (the era between 2 million and 20,000 years ago) and the year 1900, the average life expectancy at birth hardly increased at all, remaining around 30 years. Since then, as a result of the application of the scientific process to health care, it has more than doubled, with the worldwide average now being 71 years. Consider that. In just 100 years we have given ourselves more life that we managed in the previous 2 million years! Through science (the process of making observations, developing a hypothesis, testing that hypothesis and then refining and building on it) we have transformed our lives. Continue reading