Statins: side effects or not?

BHF-funded studies have led the world in showing that statins save lives by reducing the risk of heart attack and stroke. But side effects, most notably muscle weakness or pain, are reported by up to a third of people taking statins. Because these symptoms are common, it has been difficult to work out whether they are a side effect of the statin or caused by something else.

In clinical trials these side effects are reported in similar numbers by participants receiving a statin or a placebo (a dummy pill). Despite this, some people worry about the side effects of statins and in some cases this means they are reluctant to take them when their doctor recommends it. And a significant proportion stop taking their pills and lose the protection that the statin provides.

Looking at how statins affect individuals

To explore this in more detail, the BHF-funded SAMSON trial took a personalised approach to understanding more about the side effects people experience while taking statins. Led by Professor Darrel Francis at Imperial College London, the study recruited 60 people who had recently stopped taking their statins due to side effects – some of whom came forward after the study was featured in BHF’s Heart Matters magazine. The study ran for a year, and each month participants were randomly assigned to take a statin (atorvastatin), or an identical placebo tablet, or no tablets. Each day, they recorded whether they’d taken their pill and how they felt on a scale of 0 (no symptoms) to 100 (worst imaginable) using a smartphone app. If the symptoms became too severe, they were able to stop taking the tablets for that month.

The study found that 90 per cent of the symptoms that people reported while taking a statin were also experienced while they were taking a placebo. People experienced more symptoms when they were taking a tablet (either statin or the placebo) than when they were not taking a pill, and were just as likely to temporarily stop taking their placebo tablets due to side effects as they were with statins. The results, which were reported in 2020, suggest that these symptoms are nearly all linked to the “nocebo” effect – where people experience side effects from a treatment because of a negative association with it, rather than the actual biological effect of the drug.

After participants received an explanation of their results at the end of the study, half of them successfully restarted their statin. SAMSON showed that this type of personalised approach can help to empower people to get back onto a life-saving therapy, and can mean that other options can be explored for the very small number of people who do experience side effects that are directly linked to statins.

Professor Francis said: “My vision for the future, is that once someone says they’re getting bad side effects, they can be given the SAMSON kit and they can get the answers for themselves.” In the mean time, this BHF-funded research will hopefully reassure many people who would benefit from statins that may be concerned about the potential side effects, that this could save many lives.

The patient’s view

One of the participants in SAMSON was Janice Richardson, a retired nurse from West Yorkshire. Janice was originally prescribed statins in 2015 but stopped taking them several times due to developing various aches and pains, which she was convinced were because of the statin. After reading the BHF Heart Matters article about the SAMSON trial, Janice signed up. Her results showed that she experienced the same symptoms when taking the placebo as she did when taking a statin.

Janice said: “I was so surprised that my aches and pains were not due to the statins themselves – you can convince yourself of anything! I’m now very happy to be taking my statins again. Looking back, I walk a lot in the valley where I live and have plenty of stairs in my home that I go up and down multiple times a day. No wonder my body was feeling these pains!”.

A detailed look at statin side effects

The BHF is continuing to fund projects to help us get a clearer picture of the side effects of statins, both to make it even clearer that statins are very safe, and also to benefit the very small number of people who do experience side effects that are caused by the statin. Dr Christina Reith and her team at the University of Oxford have re-analysed data from large clinical trials of statins to look at the types of side effects that were reported, how often they happen, and whether any particular groups of people are more prone to side effects.

Dr Reith’s work led to the discovery that statins do not cause the majority of muscle pain symptoms commonly associated with them. Only one in 15 of reported cases of mild muscle pain or weakness were found to be attributable to statin therapy, and occurred mainly within the first year of treatment. This means that statins are not the cause of muscle pain in over 90 per cent of people who report symptoms.

The results reinforce the evidence that statins are safe, providing reassurance to the many people taking, or considering taking, these lifesaving drugs that have been proven to protect against heart attacks and strokes.

First published 1st June 2021
Last updated 30th March 2023