Statin Use in Older Adults for Primary Cardiovascular Disease Prevention Across a Spectrum of Cardiovascular Risk

Abstract

Background: There remains uncertainty regarding optimal primary atherosclerotic cardiovascular disease (ASCVD) prevention practices for older adults.

Objective: To assess statin treatment patterns and incident ASCVD among older patients for primary prevention across the spectrum of ASCVD risk.

Design: Retrospective cohort study of participants without ASCVD aged 65-79 years. Patients were stratified by age (65-69, 70-75, > 75 years) and 10-year ASCVD risk category (low/borderline, intermediate, high) based on the Pooled Cohort Equations. Multivariable logistic regressions were used to identify predictors of moderate- or high-intensity statin prescriptions. Cox proportional models were used to estimate hazard ratios (HRs) for incident ASCVD.

Participants: Patients aged 65-79 years without ASCVD from a Northern California health system.

Main measures: Statin prescriptions and incident ASCVD events.

Key results: There were 54,066 patients, with 10,288 (19%) aged > 75 years and 57% women. Compared with younger groups, adults > 75 years were less likely to be prescribed moderate- or high-intensity statin prescriptions across ASCVD risk groups (all p < 0.001); this persisted after multivariable adjustment including for ASCVD risk (odds ratio [OR] 0.80, 95% confidence interval [CI] 0.74-0.86). Adults > 75 years were more likely to experience incident ASCVD (HR 1.42, 95% CI 1.23-1.63). Women (OR 0.85, 95% CI 0.81-0.89) and underweight older adults (OR 0.45, 95% CI 0.33-0.61) were also less likely to receive moderate- or high-intensity statins.

Conclusions: Among older adults aged 65-79 years without prior ASCVD, those > 75 years of age were less likely to receive moderate- or high-intensity statins regardless of ASCVD risk compared with their younger counterparts, while experiencing more incident ASCVD. Efforts are warranted to study the reasons for age-based differences in statin use in older adults, particularly those at highest ASCVD risk.

Keywords: atherosclerotic cardiovascular disease; elderly/aged; primary prevention; statins.

Figure 1

The CONSORT diagram. ASCVD, atherosclerotic cardiovascular disease; y, years.

Figure 2

Rates of statin prescription in a primary prevention cohort of patients aged 65 through 79 years by statin intensity and ASCVD risk level. Within each ASCVD risk group, all p < 0.001 for differences in high-intensity, moderate-intensity, and low-intensity statin prescriptions between age categories. ASCVD risk level was calculated by the American College of Cardiology/American Heart Association Pooled Cohort Equations of 10-year ASCVD risk: (1) low risk (including “borderline” risk from the ACC/AHA guidelines): < 7.5%; (2) intermediate risk: ≥ 7.5% and < 20%; and (3) high risk: ≥ 20%. Rx, prescriptions; ASCVD, atherosclerotic cardiovascular disease.