Race, Gender, & Income Influence Access to SGLT2 Inhibitors Among US Patients

Srinath Adusumalli, MD, MSHP

Results of a new study from the University of Pennsylvania demonstrate significant racial inequities exist in access to SGLT2 inhibitor treatment among patients with diabetes in the US.

An analysis of data from nearly 1 million patients with type 2 diabetes from 2015-2019, results indicate overall rates of SGLT2 inhibitor prescribing are increasing but also underline significant disparities in rate of use among Black, Asian, and female patients compared to their White or male counterparts.

"These results are consistent with prior studies that have shown decreased use of novel therapies among Black patients. Implementation strategies that prioritize not only delivery of guideline-directed care but also equitable guideline-directed care are critical in ensuring all patients have access to evidence-based therapies" said the study's senior investigator Srinath Adusumalli, MD, MSHP, an Assistant Professor of Clinical Medicine in the Division of Cardiovascular Medicine, at the Perelman School of Medicine at the University of Pennsylvania, in a statement.

Few, if any, fields of care have undergone the explosion in relevance seen with the antidiabetic agents in recent years, specifically SGLT2 inhibitors. With evidence demonstrating benefit in chronic kidney disease and heart failure, greater access to medications within the class could improve the prognosis for millions of patients with diabetes.

With an interest in identifying avenues to improve prescribing rates and access to SGLT2 inhibitor use, investigators designed the current study as a retrospective cohort study of commercially insured patients in the Optum Clinformatics Data Mart from October 1, 2015 to June 30, 2019. After performing a search of patients aged 18 years or older with a diagnosis of type 2 diabetes on at least 2 visits, investigators identified 934,737 patients for inclusion in the current study.

With demographic and clinical data provided by the Optum database, investigator used multivariable logistic regression models to assess the association of race/ethnicity, gender, and socioeconomic status with SGLT2 inhibitor use. For the purpose of analysis, investigators categorized race/ethnicity of patients as Black, Latino, White, or Asian. Investigators also noted plans to assess patients according to the presence of HFrEF, ASCVD, and CKD.

A cohort of 934,737 patients was identified for inclusion in the analyses. This cohort had a mean age of 65.4 (SD, 12.9) years, 50.7% were female, and 57.6% were White. Of the 934,737 patients, 8.7% (n=81,007) were treated with an SGLT2 inhibitor during the 5-year study period.

In the overall study population, rates of SGLT2 inhibitor use increased from 3.8% in 2015 to 11.9% in 2019. During the same time period, the rate of use increased from 3.4% to 11.4% among Asian patients, 3.4% to 11.1% among Black patients, 3.8% to 13.0% among Latinx patients, and 4.0% to 12.6% among White patients.

Investigators highlighted assessments of use based on the presence of other cardiometabolic comorbidities indicated rates of use among these patients were consistently lower than those seen among the overall study cohort (HFrEF: 1.9% to 7.6%; ASCVD: 3.0% to 9.8%; CKD: 2.1% to 7.5%).

In multivariable-adjusted analyses, Black race (aOR, 0.83; 95% CI, 0.81-0.85; P <.001), Asian race (aOR, 0.94; 95% CI, 0.90-0.98; P=.002), and female gender (aOR, 0.84; 95% CI, 0.82-0.85; P <.001) were factors associated with lower rates of SGLT2 inhibitor use. Investigators pointed these analyses also suggested patients residing in a zip code with a median household income of less than $50,000 had lower odds of receiving a prescription for SGLT2 inhibitors when compared to those in areas with a median household income of $50,000-99,999 or $100,000 or more. Similar associations were observed in subgroup analyses of patients with HFrEF, ASCVD, and CKD.

Of note, results indicated an increased number of visits to a cardiologist per 12 months (aOR, 1.19 [95% CI, 1.16-1.22] for 1 visit and aOR, 1.15 [95% CI, 1.12-1.18] for more than 1 visit) and increased number of visits to an endocrinologist per 12 months (aOR, 2.06 [95% CI, 1.99-2.12] for 1 visit and aOR, 2.84 [95% CI, 2.76-2.92] for more than 1 visit) were associated with increased SGLT2 inhibitor use.

"We know there are already higher rates of heart failure and kidney disease among Black patients. What is concerning is that this is a therapy we know prevents death from those conditions and prevents progression from those conditions, and yet, we found that Black patients are less likely to get this therapy, as well as female patients and those with lower socioeconomic status,” said lead investigator Lauren Eberly, MD, MPH, a cardiology fellow at the University of Pennsylvania.

Investigators also brought attention to multiple limitations within their study to consider when interpreting the results. These limitations included the inability to differentiate between prescriptions offered and prescriptions filled, the inability to assess severity or control of type 2 diabetes, and the inability to understand clinical decision-making for individual treatment plans.

This study, “Association of Race/Ethnicity, Gender, and Socioeconomic Status With Sodium-Glucose Cotransporter 2 Inhibitor Use Among Patients With Diabetes in the US,” was published in JAMA Network Open.