The use of coronary artery calcium (CAC) scanning for heart disease diagnosis is influenced by regional and socioeconomic factors, according to research presented at the Society of Cardiovascular Computed Tomography (SCCT) meeting in Washington, DC.
A team led by Vincent Sachs, DO, of the University of South Florida in Tampa reported that U.S. counties with the lowest rates of CAC utilization have a higher population of African Americans (p < 0.001) and a higher proportion of women (p < 0.001).
"Unrepresented ethnicities [in the U.S.] such as African Americans have among the lowest rates of CAC utilization despite being known to have a higher burden and mortality from heart disease," the group wrote.
Disparities in cardiovascular care have been well documented, the authors explained, and many studies have shown that socioeconomic status is one of the strongest determinants of coronary artery disease (CAD) outcomes. But Sach's group investigated whether there are "regional variation and socioeconomic variables that impact CAC utilization across the U.S. relative to [CAD] prevalence."
The researchers conducted a study that used county-level data on CAC utilization culled from 2022 hospital commercial claims, outpatient Medicare service claims, and independent imaging center claims. They gathered information on CAD prevalence and socioeconomic variables (population, race) from the Centers for Disease Control and Prevention (CDC) and the National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP), and assembled county-level adjusted gross income per capita figures from the Internal Revenue Service (IRS). The work included 781 U.S. counties (a sample that represents 25% of counties across the country) and more than 600,000 claims.
Sach and colleagues found that median utilization of CAC was 1.62 scans per 1,000 individuals, with a range of 0.03 to 104.39. They also reported the following:
- Factors that favor higher CAC utilization include populations with a larger numbers of white individuals (p = 0.007) and a higher adjusted gross income per capita (p = 0.006).
- Counties with the lowest rates of CAC utilization had a higher population of African Americans (p < 0.001) and a higher proportion of women (p < 0.001).
- The West region of the U.S. had the highest CAC scan use rate (median 3.09 scans per 1,000 persons) and a CAD prevalence of 5.48 per 1,000 persons.
- The Midwest had the lowest CAC scan use rate, with a median of 1.23 scans per 1,000 individuals and a CAD prevalence of 6.35 per 1,000 persons.
The study results underscore a need for proactive measures to improve CAC use among underserved patients, according to the team.
"Discordance between CAC utilization, CAD prevalence, and socioeconomic status reveals a need for targeted interventions and policies aimed at mitigating structural barriers that perpetuate health inequities," it concluded.
