Use of statins in the elderly according to age and indication-a cross-sectional population-based register study.

Purpose: To investigate statin use in the elderly by age (≥ 80 vs. 65-79 years) in relation to established indications.

Methods: A population-based cohort, including data from four registers, encompassing inhabitants in Region Västra Götaland, Sweden, was used. Statin users were defined as those filling statin prescriptions ≥ 75% of the year 2010. Primary care and hospital diagnoses in 2005-2010 regarding ischemic heart disease, stroke, transient ischemic attacks, and diabetes were considered established indications.

Results: A total of 278,205 individuals were analyzed. In individuals aged ≥ 80 and 65-79 years (n = 81,885 and n = 196,320, respectively), 17% (95% confidence interval 17%; 18%) and 23% (23%; 23%) respectively, were statin users. Among the statin users, 74% (73%; 74%) of those aged ≥ 80 and 60% (59%; 60%) of those aged 65-79 years had ≥ 1 established indication. Conversely, of those with ≥ 1 established indication, 30% (30%; 31%) and 53% (52%; 53%) were on statins in the respective age groups. Logistic regression revealed that age, nursing home residence, and multi-dose drug dispensing were the most prominent negative predictors for statin use; adjusted odds ratios (95% confidence interval): 0.45 (0.44; 0.46), 0.39 (0.36; 0.42), and 0.47 (0.44; 0.49), respectively.

Conclusions: In the oldest old (≥ 80 years), statin users were fewer and had more often an established indication, suggesting that physicians extrapolate scientific evidence for beneficial effects in younger age groups to the oldest, but require a more solid ground for treatment. As the oldest old, nursing home residents, and those with multi-dose drug-dispensing were statin users to a lesser extent, physicians may often refrain from treatment in those with lower life expectancy, either due to age or to severely reduced health status. In both age groups, our results however also indicate some over- as well as undertreatment.