Race, Practice Location Still Play Major Role in Odds of PSCK9 Inhibitor Prescription

Despite well-intentioned efforts and a push for uptake in recent years, data from a new analysis of more than 2.1 million patients suggests race and practice location still play a major role in the odds of receiving a prescription for PCSK9 inhibitors.

Using data from the PINNACLE registry, the analysis provides an overview of contemporary trends in prescribing practices of PCSK9 inhibitors in patients with established atherosclerotic cardiovascular disease (ASCVD)—suggesting White race and high household income were associated with increased odds of receiving a prescription while also drawing attention to an overall prescribing rate during the study period of less than 1.5% of eligible patients.

“Among almost 2.15 million outpatients with ASCVD, overall PCSK9i prescription rates were low. Among patients with ASCVD and suboptimal LDL control, we observed racial, socioeconomic, and geographic disparities and practice-level variation in PCSK9i prescription rates,” wrote investigators.

Although the efficacy of PCSK9 inhibitor has been extensively outlined in clinical trials and other studies, uptake of the agents has been hampered by their cost and other factors. Cost-sharing initiatives and price reductions by manufacturers have improved affordability of the class, but uptake remains a persistent issue.

The present study was designed by a Massachusetts General Hospital-led team with the aim of developing a greater understanding of contemporary trends in PCKS9 inhibitor prescription for secondary prevention of ASCVD. Investigators designed their study as an analysis of the ACC’s PINNACLE Registry, which investigators noted is the largest outpatient registry of longitudinal data on patients with chronic cardiovascular disease. Using September 1, 2015-September 30, 2019 as their period of interest, investigators identified more than 2.1 million patients meeting inclusion criteria for their analysis.

For inclusion in the analysis, patients needed to remain within the PINNACLE database through the end of the study period, be at least 18 years of age or older, have a history of ACVD, and an LDL-C level less than 190 mg/dL before their index visit. For the purpose of analysis, patients already receiving an PSCK9 inhibitor were not included and those with an LDL exceeding 190 mg/dL were excluded to avoid including patients with familial hypercholesterolemia.

Investigators planned to examine potential predictors of PCKS9 inhibitor prescription using multivariable mixed-effects regression models, which they noted included covariates as fixed effects and the specific cardiology practice as a random effect. Investigators pointed out patient data, including demographic and clinical information, were used as covariates. Specific covariates included but were not limited to age, sex, estimated household income, zip code, race, and insurance type.

In total, 2,148,100 patients from 759 outpatient cardiology practices were identified for inclusion. Among these patients, only 1.3% (n=27,249) received a prescription for a PCSK9 inhibitor. Of those who did, 19,398 received evolocumab and 7851 received alirocumab. Investigators noted 251 of 759 practices reported having 0 patients receiving PCSK9 inhibitor prescriptions.

Compared to their counterparts who did not receive a prescription for a PCKS9 inhibitor, recipients were younger (66.6 vs 68.6 years), more likely to be female (43.4% vs 42.3%), less likely to be Black (4.6% vs 5.6%) or Hispanic (3.7% vs 4.2%), and more likely to have private health insurance (67.1% vs 55.1%) (P for all <.001). In adjusted analysis, results suggested White race e (versus non-White: OR, 1.78 [95% CI, 1.55–1.83]), high estimated household income (versus low income: OR, 1.18 [95% CI, 1.08–1.29]), and urban or suburban (versus rural) practice location (urban: OR, 1.47 [95% CI, 1.32–1.64]; suburban: OR, 1.25 [95% CI, 1.13–1.39]) were associated with increased odds of receiving a prescription for a PCKS9 inhibitor.

Further analysis revealed clinically significant practice-level variation in PCSK9 inhibitor prescriptions, with investigators highlighting a mean adjusted odds ratio of 2.68 (95% CI, 2.46-2.94). Additionally, investigators pointed out there were no differences observed in quarterly prescription rates before and after price reductions of evolocumab and alirocumab.

“These findings highlight the need to improve equitable access to PCSK9i among minorities and the poor, and to further understand and address drivers of practice-level variation in adoption of PCSK9i and other promising new therapies,” wrote investigators.

This study, “Predictors of PCSK9 (Proprotein Convertase Subtilisin/Kexin Type 9) Inhibitor Prescriptions for Secondary Prevention of Clinical Atherosclerotic Cardiovascular Disease,” was published in Circulation: Cardiovascular Quality and Outcomes.