Disparities in Statin Use for ASCVD Unexplained by Disease Severity, Structural Factors

Ravy K. Vajravelu, MD

Credit: University of Pittsburgh

New findings from a nationally representative analysis revealed a lower prevalence of statin use for the primary prevention of atherosclerotic cardiovascular disease (ASCVD) among non-Hispanic Black men and non-Mexican Hispanic women, compared with non-Hispanic White men.¹

The trend continued into secondary prevention of ASCVD, with a lower prevalence of statin use observed in non-Hispanic Black men, multiracial men, Mexican American women, non-Mexican Hispanic women, non-Hispanic White women, and non-Hispanic Black women, compared with non-Hispanic White men.

“These disparities were not explained by measurable differences in disease severity or access to resources, and therefore may be partially mediated by care process factors, including bias, stereotyping, and mistrust,” wrote the investigative team, led by Ravy K. Vajravelu, MD, from the division of gastroenterology, hepatology, and nutrition at the University of Pittsburgh School of Medicine. “Because those statin use disparities may contribute to disparities in overall cardiovascular morbidity and mortality, they highlight the importance of societal interventions to health delivery systems to reduce inequity in care delivery and treatment."

A class of medications that reduce low-density lipoprotein cholesterol (LDL-C) levels, statins are a class 1 recommendation for the prevention of ASCVD and its complications. However, despite these recommendations, the rates of guideline-recommended statins remain suboptimal and could contribute to disparities in cardiovascular health outcomes.² A clearer understanding of racial, ethnic, and gender-based differences in statin use could better inform strategies to improve these outcomes on the population level and particularly for systematically marginalized individuals.

Using cross-sectional, health status data from the National Health and Nutrition Examination Survey (NHANES) 2015 - 2020, the investigative team aimed to estimate differences in guideline-recommended statin use by race, ethnicity, and gender for primary and secondary prevention of ASCVD. In order to understand whether these potential disparities are explained by factors influencing the medical appropriateness of statin use, the team calculated the prevalence of statin use adjusted for age and disease severity.

The analysis focused on patients eligible to receive statin therapy by class I recommendations in the 2013 and 2018 American College of Cardiology/American Heart Association (ACC/AHA) blood cholesterol guidelines. For primary prevention, it included individuals without ASCVD aged 21 - 75 years with an LDL-C of ≥190 mg/dL, aged 40 - 75 years with diabetes, or aged 40 - 75 years with a 10-year ASCVD risk of ≥7.5%. For secondary prevention, it included individuals aged 21 - 75 years with clinical ASCVD.

Race-ethnicity-gender served as the independent variable and the main outcome of interest was the use of a statin. Utilizing the Institute of Medicine framework to examine unequal treatment, investigators calculated adjusted prevalence ratios (aPRs) to estimate disparities in statin use, with adjustments for age, disease severity, healthcare access, and socioeconomic status, compared with non-Hispanic White men.

Investigators identified 13,213 participants in NHANES aged 21 - 75 years and a total of 4,763 participants were eligible to receive a statin for the primary prevention of ASCVD. The overall prevalence of statin use for primary prevention was 37.6% (95% CI, 33.9% - 41.5%)

In primary prevention, investigators observed a lower prevalence of statin not explained by measurable differences in disease severity, access to health care, and socioeconomic status among non-Hispanic Black men (aPR, 0.73; 95% CI, 0.59 - 0.88) and non-Mexican Hispanic women (aPR, 0.74; 95% CI, 0.53 - 0.95), relative to non-Hispanic White men.

For secondary prevention, the overall prevalence of statin use was 59.1% (95% CI, 54.8 - 63.2). Investigators once more observed a lower prevalence of statin use not explained by measurable differences in disease severity or structural factors for non-Hispanic Black men (aPR, 0.81; 95% CI, 0.64 - 0.97), multiracial men (aPR, 0.58; 95% CI, 0.20 - 0.97), Mexican American women (aPR, 0.36; 95% CI, 0.10 - 0.61), non-Mexican Hispanic women (aPR, 0.57; 95% CI, 0.33 - 0.82), non-Hispanic White women (aPR, 0.69; 95% CI, 0.56 - 0.83), and non-Hispanic Black women (aPR, 0.75; 95% CI, 0.57 - 0.92).

As statin use disparities contribute to disparities in overall cardiovascular health, the investigative team highlighted the importance of societal interventions in health delivery systems to reduce inequities for these patient populations.

“These include clinical quality improvement initiatives to systematize statin prescriptions among eligible patients, bias reduction training for prescribers, diversification of the health care provider workforce, and programs to regain trust among systematically marginalized groups that have experienced intergenerational scientific and clinical misconduct,” investigators wrote.

References

1. David A. Frank, Amber E. Johnson, Leslie R.M. Hausmann, et al. Disparities in Guideline-Recommended Statin Use for Prevention of Atherosclerotic Cardiovascular Disease by Race, Ethnicity, and Gender: A Nationally Representative Cross-Sectional Analysis of Adults in the United States. Ann Intern Med. [Epub 25 July 2023]. doi:10.7326/M23-0720
2. Mangione CM, Barry MJ, Nicholson WK, et al; US Preventive Services Task Force. Statin use for the primary prevention of cardiovascular disease in adults: US Preventive Services Task Force recommendation statement. JAMA. 2022;328:746-753. [PMID: 35997723] doi:10.1001/jama.2022.13044