It’s a controversial topic in Australia, but data from the US is suggesting that use of statins in people aged over 75 for primary prevention could save lives.
Just because you’re over the age of 75 doesn’t mean you shouldn’t get access to statins as a form of primary prevention, a US study suggests.
In a study published in JAMA this week, the risk of CVD death was significantly lower in people aged over 75 who took statins as a form of primary prevention than those who didn’t.
The retrospective cohort study tracked over 300,000 US veterans aged over 75 with no pre-existing atherosclerotic cardiovascular disease.
The patients in the study were mostly white men, aged 81 on average.
Around 18% of participants started taking statins during the study period, the rest did not take statins. Simvastatin was the most commonly prescribed statin in the study.
The patients who started on statins were more likely to have hyperlipidemia, hypertension, diabetes or arthritis.
Over the seven years of the study, about two-third of the patients died. Around 50,000 of these deaths were due to cardiovascular disease.
Statin users had a 20% reduced risk of CVD death, a 25% reduced risk of all-cause mortality, and 8% reduced risk of atherosclerotic cardiovascular disease events compared with non-statin users over the seven-year follow up period.
“Results remained consistent even at advanced ages and in those with comorbidities, with similar lower risk for mortality observed in statin users 90 years and older or with dementia,” the authors reported.
The findings supported several American clinical guidelines, which did not have a cutoff age for use of statins for primary prevention and recommended considering prescribing statins to those 75 years and older, the authors said.
The use of statins for primary prevention in people aged over 75 is still controversial in Australia and clinical guidelines are unclear on this point.
There’s a lack of data around the use of statins in older people because major statin trials excluded people aged over 75.
Some Australian doctors would still prescribe statins for primary prevention in over 75s if they believed it was unwise to wait until a high-risk patient had a major cardiac event before initiating preventative medication, said Sydney GP Dr Brad McKay.
Some guidelines suggest patients should have a life expectancy of more than five years to continue being on a statin, he said. Palliative care physicians and geriatricians will usually cross statins and other preventative medications off a patient’s medical chart when they are reviewed in hospital, he said.
A recently published Australian study (the ASPREE trial) looked at the effects of statins for primary prevention in older patients.
This study was a prospective, randomised trial for aspirin in patients aged over 70 but was also analysed as an observational study for statins as around 5,600 participants (out of around 18,000) were taking statins at baseline.
Over the follow up of around five years, statin use was found to prevent physical disability and CVD but was not beneficial for prolonging disability-free survival or avoiding death or dementia.
“The problem with both [our study and the JAMA study] is they are observational and therefore can only demonstrate association and a subject to residual confounding,” said Professor Mark Nelson, the chair of general practice at the University of Tasmania who was the lead author on the study.
Professor Nelson is involved in the STAREE trial, which will examine the use of statins in patients aged over 70 prospectively.
There are numerous studies that provide mixed observational findings about the use of statins in older patients, including a 2019 French study which found that statin discontinuation was associated with a 33% increased risk of hospital admission for cardiovascular events.
A meta-analysis of 22 trials published in The Lancet last year found that statin therapy reduced major vascular events irrespective of age, but there was less direct evidence of benefit among patients older than 75 years who did not already have evidence of occlusive vascular disease.
