Assessment of Trends in Statin Therapy for Secondary Prevention of Atherosclerotic Cardiovascular Disease in US Adults from 2007 to 2016

Importance: Atherosclerotic cardiovascular disease (ASCVD) is highly prevalent in the US, with studies indicating substantial rates of nonadherence to and undertreatment with statin therapy. The 2013 American College of Cardiology/American Heart Association guideline recommended high-intensity statins for all patients age 75 years and younger with documented ASCVD in whom such therapy is tolerated, but there is limited evidence documenting population trends of statin use, adherence, and outcomes in the periods before and after the update to the guideline. Objective: To assess trends in the use, adherence, cost, and outcomes of statin therapy for secondary prevention in patients with different types of ASCVD between 2007 and 2016. Design, Setting, and Participants: This retrospective cohort study used data from the OptumLab Data Warehouse database containing privately insured and Medicare Advantage enrollees with demographic characteristics similar to the national US population. Participants were adult patients (age ≥21 years) who had their first ASCVD event between January 1, 2007, and December 31, 2016. Data were characterized as belonging to 3 groups: (1) cardiovascular heart disease (CHD); (2) ischemic stroke or transient ischemic attack (TIA); and (3) peripheral artery disease (PAD). Data were analyzed from July 1 to August 1, 2018. Exposures: Calendar year of the initial ASCVD event. Main Outcomes and Measures: Trends in the statin use (within 30 days of discharge from hospitalization), adherence (proportion of days covered ≥80% within the first year), cost, major adverse cardiac events (1-year cumulative risk), and statin intolerance (within the first year). Results: Of the 284954 patients with a new ASCVD event, 128422 (45.1%) were women; the median age was 63 years (interquartile range [IQR], 54-72 years); 207781 (72.9%) were White. The use of statins increased from 50.3% in 2007 to 59.9% in 2016, the use of high-intensity statins increased from 25.0% to 49.2%, and the adherence increased from 58.7% to 70.5% (P <.001 for all trends). Patients with CHD were more likely to receive statins and high-intensity statins and adhere to medications than patients with ischemic stroke, TIA, or PAD despite similar observed treatment benefit. In 2016, 80.9% of patients with CHD used a statin vs 65.8% of patients with ischemic stroke or TIA and 37.5% of patients with PAD. Out-of-pocket cost per 30-day decreased from a median of $20 (interquartile range, $7.6-$31.9) in 2007 to $2 (interquartile range, $1.6-$10.0) in 2016 (P <.001) with the increasing use of generic statins (42.0% in 2007 vs 94.9% in 2016; P <.001). Major adverse cardiac events decreased from 8.9% in 2007 to 6.5% in 2016 (P <.001) whereas statin intolerance increased from 4.0% to 5.1% (P <.001). Conclusions and Relevance: There have been modest improvements in the use, adherence, and cardiovascular outcomes over the past decade for statin therapy in patients with ASCVD, but a substantial and persistent treatment gap exists between patients with and without CHD, between men and women.