Continuous Glucose Monitoring Access—Addressing Racial and Ethnic Disparities in Diabetes (2024)

Continuous glucose monitoring (CGM) technology has transformed diabetes management and insulin administration over the past 2 decades. Use of CGM has been shown to improve diabetes control, supporting patients with type 1 or type 2 diabetes to achieve goal hemoglobin A_1c (HbA_1c) levels and decrease their risk of severe hypoglycemia.¹ Although CGM was initially only approved for use in patients with type 1 diabetes, based on evidence of clinical benefit for patients with type 2 diabetes, professional society guidelines now recommend the use of CGM in all patients with diabetes who are receiving insulin therapy.² However, despite guideline recommendations, CGM continues to be underutilized, particularly among ethnic and racial minority groups.³ As highlighted by the findings of Wallia et al⁴ in a recent study in JAMA Network Open, a major factor leading to low CGM use among patients from racial and ethnic minority groups is low CGM prescription rates.

The study by Wallia et al⁴ investigates the current state of CGM prescription for patients with type 1 and type 2 diabetes receiving care in a large US network of federally qualified health centers (FQHCs).⁴ In this retrospective analysis of electronic health record data from 1168 patients with type 1 diabetes and 35 216 patients with type 2 diabetes receiving primary care in FQHCs, the authors found low rates of CGM prescription orders overall (11% for patients with type 1 diabetes and 1% for patients with type 2 diabetes), disproportionately lower prescription orders among patients who identified as Hispanic or Black compared with those who identified as non-Hispanic White, and lower rates among patients without health insurance compared with those with health insurance. CGM prescription order rates were higher among patients with type 2 diabetes who were prescribed insulin, had higher HbA_1c, or who had more diabetes comorbidities compared with those not receiving insulin, with HbA_1c at goal, or with fewer diabetes comorbidities. However, ethnic and racial disparities in CGM prescription orders remained after controlling for these factors and for insurance status.

Racial and ethnic disparities in CGM use among patients with type 1 diabetes are well-documented and have been attributed to high costs and limited insurance coverage for this technology. More recent studies have demonstrated unequal access to CGM for patients with type 1 diabetes even after controlling for insurance coverage.³ The study by Wallia et al⁴ contributes to an emerging body of evidence of racial and ethnic disparities in CGM use that also affect the much larger population of patients with type 2 diabetes and which similarly exist independent of insurance coverage. In a study of a national sample of more than 350 000 veterans with diabetes taking insulin therapy receiving care through Veterans Health Affairs, Lipska et al⁵ also found racial and ethnic disparities in CGM prescription, with lower odds of CGM prescription for Black or Hispanic patients compared with White or non-Hispanic patients, respectively. Costs for initiating and maintaining use of CGM technology are covered for eligible veterans, and disparities persisted after accounting for zip code area deprivation index, so financial considerations were thought unlikely to explain the findings. Disparities also persisted after controlling for differences in comorbidities, clinical indication for CGM, and access and receipt of care in endocrinology clinics. Interestingly, in a similar study focused on patients in an FQHC system who were eligible for CGM at no cost through their Medicaid plan, Ni et al⁶ found no racial and ethnic disparities in CGM prescriptions or in CGM utilization. CGM prescription rates in this study were also much higher than those found by Willia at al,⁴ with 16% of patients with type 2 diabetes and 74% of patients with type 1 diabetes receiving CGM prescriptions. However, the observation time for the Ni et al⁶ study ended in 2022, whereas that of the Wallia et al⁴ study ended in 2021, and therefore the higher prescription rates in the former could in part reflect increasing CGM prescription rates over time rather than differences between the 2 systems.

The question of how to achieve equitable CGM use remains a complicated one. Recognition that disparities exist at the prescription level is helpful, but the system-level factors serving as mediators of those disparities still need to be identified. Disparities at other steps in the process (prescription fill, initial use, and maintained use) and factors mediating those disparities will also need to be identified and addressed. While disparities in CGM prescription rates could be interpreted as being solely a reflection of biased clinician behavior, they may also reflect group differences in access to clinician visits, inadequate diabetes education support for patients, lack of support for clinicians to navigate complex prior authorization requirements, or many other system-level factors. In the study by Ni et al,⁶ barriers to CGM prescription and use may have been mitigated by nurse and pharmacist support for CGM use, wide availability of CGM in community-based pharmacies, availability of CGM at no cost to the patient, and lack of prior authorization requirements. Additional research of clinician perspectives on CGM prescription behavior and awareness of CGM clinical benefits is still needed.

Evidence demonstrates that CGM use can be beneficial for patients from underserved populations. In the study by Ni et al,⁶ CGM use by patients with type 2 diabetes was associated with a mean HbA_1c decrease of 1.2%, and this improvement was observed across all racial and ethnic groups.⁶ A subsequent qualitative study⁷ of CGM users from the same FQHC system revealed that in general, patients found CGM easy to use and appreciated the benefit of being able to monitor their blood glucose more discreetly than when using traditional fingerstick glucose monitoring. Participants reported using CGM data to guide changes in their diet and exercise habits, to reassure themselves that clinician-recommended changes in their medications were not resulting in low blood glucose, and to identify decreasing blood glucose trends to prevent severe hypoglycemia. Participants also reported improved communication with their primary care clinicians in association with CGM use.

As use of CGM and other diabetes technology become standard of care for diabetes management, ensuring equitable access across racial, ethnic, and other social demographic groups could serve as an opportunity to decrease existing disparities in diabetes morbidity and mortality, while continued disparate access would be expected to result in widening diabetes health disparities. Continued research is needed to identify and address mediators of existing CGM use disparities affecting vulnerable populations.

Article Information