Study Finds Higher Health Care Expenditures for Patients With ASCVD, Diabetes

Patients with both diabetes and atherosclerotic cardiovascular diseases (ASCVD) had about 1.5 times higher total direct health care expenditures compared with those with ASCVD alone, according to a study published in Cardiovascular Diabetology.¹

The researchers explained that ASCVD is associated with heightened costs due to the increasing number of life-prolonging therapies patients must implement.² Consequently, CVD-related costs are projected to reach $818 billion annually for direct costs and $276 billion for indirect costs by 2030.³ Compared to the general population, diabetes increases CVD risk at least twofold, with ASCVD being the most common complications for patients with diabetes.^4,5 Therefore, managing ASCVD in combination with comorbidities like diabetes mellitus complicates expenses.¹

However, limited studies have analyzed the impact of comorbidities like diabetes on direct costs. Therefore, it largely remains unclear how the coexistence of diabetes with ASCVD affects direct medical costs for hospitalizations, outpatient visits, and other medical services. Because of this, researchers conducted a study to examine changes over time in direct health care expenditures among adult patients with ASCVD with and without diabetes.

Patients with both diabetes and atherosclerotic cardiovascular disease (ASCVD) have about 1.5 times higher total direct health care expenditures than those without diabetes. | Image Credit: jirsak - stock.adobe.com

To do so, data were collected from the 2008 to 2019 Medical Expenditure Panel Survey (MEPS), the largest nationally representative survey of US medical costs. MEPS samples data from about 39,000 individuals annually to estimate the use of medical resources among the US population.

The study focused on US adults aged 18 or older with an ASCVD diagnosis. The researchers included patients from MEPS based on the availability of an ASCVD diagnosis. ASCVD and diabetes were diagnosed based on self-reports, which they transcribed and classified based on the International Classification of Disease (ICD)-9 and ICD-10 codes.

The primary outcome of interest was the annual overall health care related-costs. After adjusting for demographics, comorbidities, and time, the researchers used a 2-part model to estimate mean and adjusted incremental medical expenditures by diabetes status among patients with ASCVD. The researchers further stratified overall health care-related costs into 2 mutually exclusive contributing components: prescription drug and medical costs. They estimated the direct medical costs by point of service, including office-based visits, pharmacy, and emergency room.

The study population consisted of 28,144 patients with ASCVD, of which 9599 had diabetes. The researchers noted that the prevalence of diabetes increased from 28.37% between 2008 and 2009 to 32.10% between 2018 and 2019. Compared to those without diabetes, patients with ASCVD and comorbid diabetes were older (67.30 years vs 65.27 years) and more likely to be Hispanic (20.53% vs 15.30%) or Black (24.33% vs 18.70%); also, a larger proportion of patients with ASCVD and comorbid diabetes are on public insurance (54.18% vs 43.86%).

Among patients with ASCVD, the total mean unadjusted direct expenditures increased continuously by 30% from $14,713 (95% CI, $13,808-$15.629) between 2008 and 2009 to $19,145 (95% CI, $17,988-$20,301) between 2018 and 2019. However, patients with ASCVD and comorbid diabetes faced a corresponding increase of 26% in overall cost from $20,539 (95% CI, $18,688-$22,389) between 2008 and 2009 to $25,878 (95% CI, $23,496-$28,260) between 2018 and 2019.

The researchers noted that a key factor of these increasing costs was rising prescription drug costs. Drugs for patients with ASCVD increased by 37% from $3378 (95% CI, $3162-$3594) between 2008 and 2009 to $4618 (95% CI, $4172-$5064) between 2018 and 2019. This increase was more pronounced among patients with ASCVD and diabetes, who faced a 45% increase in prescription drug costs from $5184 (95% CI, $4721-$5646) between 2008 and 2009 to $7501 (95% CI, $6678-$8325) between 2018 and 2019.

After adjusting for demographics, comorbidities, and time, the researchers estimated the diabetes-related adjusted mean annual overall incremental cost among patients with ASCVD to be $5563 (95% CI, $4643-$6483). Also, the corresponding medical care and prescription drugs costs were $3071 (95% CI, $2278-$3865) and $2493 (95% CI, $2238-$2748), respectively; prescription drug costs accounted for almost 45% of the diabetes-related incremental overall cost among patients with ASCVD.

Overall, the researchers estimated the annual aggregate cost among US adults with ASCVD between 2008 and 2019 to be $394 billion. Additionally, the estimated adjusted total direct excess medical expenditures due to diabetes among US patients with ASCVD at the population level was $42 billion per year.

The researchers acknowledged their limitations, including comorbidities being self-reported, meaning there was a potential for bias. Also, they derived the costs using survey data, so degrees of error were possible. Despite these limitations, the researchers suggested future interventions based on their findings.

“…interventions directed towards preventing and managing metabolic factors, such as diabetes, could have a significant impact on the trajectory of the overall ASCVD-related costs,” the authors wrote. “Improved care access, systems of care, awareness on diet and physical activity, and reducing ASCVD risk factors, such as diabetes, are ways to minimize the substantial burden.”

References

1. Shah CH, Fonarow GC, Echouffo-Tcheugui JB. Trends in direct health care costs among US adults with atherosclerotic cardiovascular disease with and without diabetes. Cardiovasc Diabetol. 2024;23(1):238. doi:10.1186/s12933-024-02324-w
2. Martin SS, Aday AW, Almarzooq ZI, et al. 2024 heart disease and stroke statistics: a report of US and global data From the American Heart Association. Circulation. 2024;149(8):e347-e913. doi:10.1161/CIR.0000000000001209
3. Heidenreich PA, Trogdon JG, Khavjou OA, et al. Forecasting the future of cardiovascular disease in the United States: a policy statement from the American Heart Association. Circulation. 2011;123(8):933-944. doi:10.1161/CIR.0b013e31820a55f5
4. Emerging Risk Factors Collaboration, Sarwar N, Gao P, et al. Diabetes mellitus, fasting blood glucose concentration, and risk of vascular disease: a collaborative meta-analysis of 102 prospective studies. Lancet. 2010;375(9733):2215-2222. doi:10.1016/S0140-6736(10)60484-9
5. Shah AD, Langenberg C, Rapsomaniki E, et al. Type 2 diabetes and incidence of cardiovascular diseases: a cohort study in 1·9 million people. Lancet Diabetes Endocrinol. 2015;3(2):105-113. doi:10.1016/S2213-8587(14)70219-0