Millions of Britons over 75 who take statins may be able to stop the drugs without increasing their risk of death, researchers have suggested.

French scientists found that older adults who hadn't suffered a heart attack or stroke previously were not significantly more likely to suffer one within three years of quitting the pills.

Around eight million adults in the UK are prescribed the life-saving medication, around 1.5million of whom are over 75.

Hailed as 'wonder drugs', they are given to patients at risk of cardiovascular disease (CVD) – a group of conditions that affect the heart and blood vessels – when lifestyle changes have not worked.

Previous studies have hailed the medicine for preventing some 80,000 heart attacks and strokes every year in Britain.

Statins work by interfering with the liver's production of 'bad' cholesterol – the fatty substance that damages blood vessels and is a major cause of heart attacks and strokes.

In the majority of cases – some 75 to 80 per cent – they are prescribed to prevent an initial cardiovascular attack, rather than stop a subsequent one from happening.  

This is known medically as primary prevention.

In a study, a team led from Bordeaux University Hospital examined potential outcomes of quitting the pills in older, primary prevention patients with no history of heart disease or strokes.

Until now, this type of research has largely excluded patients older than 70, the researchers noted. 

The study enrolled 1,160 adults, with an average age of 80, who were registered with general practices in France.

They were randomly assigned to two groups – some stopping statins, and those continuing to take them.

The type of medication tested in the study were the main types found in the UK: simvastatin, pravastatin, atorvastatin, rosuvastatin and fluvastatin.

After three years of follow-up, 7.2 per cent of participants who stopped taking statins died, compared to 7.9 per cent of those who continued to take them.

Some 5 per cent of patients who stopped had a 'major cardiovascular event' – such as stroke – compared to 4.4 per cent of participants who continued.

Heart attacks occurred in 2.1 per cent of quitters, compared to 1.4 per cent in those who continued.

And 14 people who stopped taking statins had a non-fatal stroke, compared to 12 who kept taking them.

The authors, whose findings were published in the The Lancet Healthy Longevity journal, said any differences between the two groups were not statistically significant.

They concluded that discontinuing statins was 'noninferior to continuing statins', meaning there was no real benefit to taking the drug.

However, the team did note a 50 per cent rise in low-density lipoprotein (LDL) – or 'bad' cholesterol – in those who discontinued treatment.

A build up of LDL cholesterol in the blood vessels can narrow the arteries, reducing blood flow and increasing the risk of heart disease and stroke.

Experts say healthy levels of LDL sit below 116mg/dl (milligrams per decilitre).

Participants in the study who stopped taking statins saw their level of bad cholesterol rise, on average, from 115mg/dl to 171mg/dl within three months of quitting.

Among those who continued using statins, levels remained at a stable level of 112mg/dl, on average.

The team acknowledged that the study had a range of limitations. This included the relatively small number of participants, and their particularly healthy lifestyles which may have influenced their heart risk.

Experts not involved in the study urged caution. Robert Storey, a professor of cardiology at the University of Sheffield, said the findings 'should not be used to inform decision-making in the majority of people treated with a statin in this age group'.

He said research into the benefits of statins on life expectancy should include thousands of people, and that the slightly increased risk of heart attack the researchers found should 'at least raise a note of caution about stopping statins'.

Professor Storey added the study found 'no evidence of a detrimental effect of continuing treatment with a statin' when it came to the quality of life.

He warned: 'There is a risk that [the research] will promote stopping of statins in people over 75 who may otherwise benefit from reduced heart attack risk.'

Bryan Williams, chief scientific and medical officer at the BHF, said the study provides 'good insights' but also noted that the findings are limited.

He added: 'The study findings should not be interpreted as evidence that statins are no longer beneficial. 

'On the contrary, for the many millions of patients taking statins in the UK, they are life-saving medications. 

'It is important to note that these findings are not relevant to many millions with a history of heart attack, stroke or other cardiovascular conditions that put them at high risk. 

'Any decisions about changing or stopping statins should be only taken together with your doctor.'

Separate studies into statins have long highlighted their benefits. 

A major piece of research from 2013 found that adults taking statins – with an average age of 57 – had a 14 per cent lower risk of dying from any cause, compared to those who don't take the pills.

This work, which was published in the Cochrane Database of Systematic Reviews, saw researchers analyse 18 different trials over a five-year follow-up period.