Melbourne, Australia—Older patients initiating a statin might be even less adherent than pharmacists might think.

A large study in the British Journal of Clinical Pharmacology found that, among 22,340 Australians aged 65 years and older who started using statins from 2014 to 2015, 55.1% were nonadherent, which was defined as failure to take the drugs at least 80% of the time in the first year after receiving their prescription. More surprising, according to Monash University researchers, is that 44.7% had discontinued use of the drugs altogether.

The study determined that age of 85 years or older, diabetes, anxiety, and being initiated on statins by a general practitioner, not a specialist, all were associated with higher likelihood of nonadherence and discontinuation. On the other hand, according to the researchers, hypertension, angina, congestive heart failure, and polypharmacy, i.e., concurrent use of five or more drugs, were all associated with a lower likelihood of nonadherence and discontinuation.

“The study findings highlight the need for interventions to improve statin use among older adults—in order that the benefits of statins can be realized—and recognition that certain sub-groups of people may require additional attention,” pointed out senior author Danny Liew, PhD, of Monash University.

The analysis separated 4,841 general beneficiaries with a higher copayment from 17,499 concessional beneficiaries with a lower copayment, and found that general beneficiaries had a higher rate of both nonadherence and discontinuation. With 55.1% nonadherent during the one-year follow-up, the rate for concessional beneficiaries was 52.6% versus 64.2% for general beneficiaries. In terms of discontinuation, that occurred with 43.1% of concessional beneficiaries and 50.4% of general beneficiaries.

In addition, researchers found that, among concessional beneficiaries, those aged 75 to 84 years and those 85 years and older were more likely to discontinue than people aged 65 to 74 years (odds ratio 1.11, 95% CI 1.04-1.19 and 1.38, 1.23-1.54, respectively).

Also associated with an increased likelihood of nonadherence and discontinuation was diabetes, while hypertension, angina, and congestive heart failure were associated with a lower likelihood of nonadherence and discontinuation, the study notes.

In that group, anxiety was associated with an increased likelihood of discontinuation, but polypharmacy was associated with a lower likelihood of nonadherence and discontinuation. Statin initiation by a general medical practitioner was associated with increased likelihood of both nonadherence and discontinuation, the study states, noting that similar predictors of nonadherence and discontinuation were identified for the general beneficiaries.

“Among older adults prescribed statins, first-year nonadherence and discontinuation are high,” study authors conclude. “Specific population subgroups such as people aged ≥85 years, those with diabetes or anxiety may require additional attention to improve statin adherence.”

 « Click here to return to Weekly News Update.