(161) Trends in Statin Initiation for Secondary Prevention of Atherosclerotic Cardiovascular Disease Among Older Adults

Publication Number: 835

Background: Statins are a mainstay for secondary prevention of atherosclerotic cardiovascular disease (ASCVD) in older adults. However, guidelines regarding initiation and intensity of statins in adults with ASCVD > 75 years old (y/o) remain unclear, due in large part to a very small number of statin trial participants > 75 y/o. As such, there is a need to evaluate real-world statin initiation among older adults.

Objectives: We sought to characterize trends in and determinants of statin initiation among older adults with particular focus on the influence of age (>75 y/o vs 66-75 y/o) following diagnosis of ASCVD.

Methods: We conducted a retrospective cohort study using Medicare Fee-For-Service claims from 2011-2018 to identify adults ≥66 years old with first ASCVD event (myocardial infarction (MI) or stroke/transient ischemic attack [TIA]). Patients were excluded if they had a gap in continuous Part A, B, or D insurance in the 365 days before and 30 days after ASCVD event or used statins in the year before ASCVD event. Patients were also excluded if they were discharged to hospice or SNF or died within 30 days of ASCVD event. We conducted multivariable logistic regression to examine determinants of statin (any intensity) initiation and high-intensity statin initiation adjusted for age, sex, race, congestive heart failure (CHF), chronic kidney disease (CKD), diabetes (T2DM), and frailty.

Results: We identified 90,620 older adults with an index ASCVD event who were not treated with a statin in the baseline period. 38,250 (42%) older adults were initiated on a statin within 30 days of ASCVD hospital discharge date. Adults >75 y/o (vs. 66-75 y/o) were less likely to be initiated on a statin (OR 0.87 [CI 0.84-0.89]). Older adults who were female, had CHF, or CKD were also less likely to be initiated on a statin. Among those initiated on a statin, adults >75 y/o (vs. 66-75 y/o) were less likely to be started on a high-intensity (vs. low-to-moderate intensity) statin (OR 0.77 [CI 0.74-0.81]). Moderate-to-severe frailty (vs. robust) was associated with a lower odds of statin initiation (OR 0.28 [CI 0.25-0.31]) but not with the choice of a high-intensity statin (OR 0.95 [CI 0.76-1.18]).

Conclusions: Adults > 75 y/o who were diagnosed with ASCVD appear less likely to be started on a high-intensity statin, as well as on a statin altogether. Frailty among older adults appears to influence the choice to initiate a statin or not more than the intensity chosen.