Statins in older adults

Editor, – The recent article (Aust Prescr 2013;36:79-82) suggests statins could be less effective in older patients, may have more adverse effects and should be used in lower doses.

While this may be true in seriously ill patients or those with dementia, we feel that there is insufficient evidence to follow this advice in otherwise fit elderly people. The fact that the relationship of cholesterol to cardiac events in the elderly is less consistent does not negate trials showing a decrease in events no matter what the starting cholesterol is, or the greater decrease in events in higher compared to lower dose statins. With an increased incidence of events in the elderly, the absolute drop with statins may well be greater.

The evidence on loss of memory with statins is minimal in otherwise fit elderly patients. There are anecdotal reports of this only. Myopathy requires drug cessation but this is in the minority of patients. Risks with liver enzyme elevation appear slight at the most.

We feel that following the advice in the article could increase cardiac and other atherosclerotic events in otherwise well elderly people.

Mark Sheppard
Cardiologist

Alistair Begg
Cardiologist

SA Heart
Adelaide

Sarah Hilmer and Danijela Gnjidic, the authors of the article, comment:

We thank Mark Sheppard and Alistair Begg for pointing out the limitations of making clinical judgements based only on chronological age. In older people, in the presence of increasing inter-individual variability, biological age, which is analogous to the degree of frailty, is a much better predictor of outcomes than chronological age. Amongst older people, frailty affects the use, pharmacokinetics, pharmacodynamics, safety and efficacy of medicines.^1,2

Clinical trials in older people do not show benefits of statins for primary prevention of cardiovascular disease.³ The participants in these trials are generally fit. The frail are predominantly excluded based on comorbidity, co-medication or impaired physical or cognitive function. In frail older people, we know more about adverse events (from observational studies) than we do about efficacy, which requires randomised controlled trials.⁴

We wish to clarify what is known about adverse effects of statins in fit older people. The majority of the evidence that statins cause cognitive impairment is from case reports and case series, in which the impairment was generally reversible within days to weeks of stopping the statin. Therefore, if statin-associated cognitive decline is suspected, it is reasonable for clinicians to consider a trial of statin withdrawal. Amongst clinical trial participants who were generally fit, myalgias were reported in 5–10%, myositis in 0.1–0.2%, and rhabdomyolysis was rare. A clinician treating one hundred fit older patients, 40% of whom are taking statins, is expected to see 2–4 patients with myalgias. The elevated hepatic transaminases observed with statins are of uncertain clinical significance.

The prescription of statins for primary prevention should be individualised on the basis of clinical judgement.⁵ Our article aims to raise awareness of the benefits and risks of statins to help clinicians apply the existing evidence to their patients.