Continuous SC insulin infusions (CSII) has been shown to provide better glycemic control than multiple daily injections (MDI) of insulin. More intensive control reduces the risk of microvascular complications. However, availability of these advanced technologies, does not necessarily equate to accessibility of these devices.

A retrospective cohort study was conducted to evaluate the role of CSII compared with MDI or fixed-dose insulin (FDI) on glucose control [as determined by the hemoglobin A1C (HbA1C)] and on hospitalizations for diabetic ketoacidosis (DKA) in young adults receiving Medicaid. Sensor-augmented pumps (SAPs) contain three main components: an insulin smart pump, a continuous glucose monitoring (CGM) system, and therapy-management software. Like SAPs, hybrid closed-loop systems are also comprised of an insulin pump and CGM, but they contain an algorithm that correlates pump data and CGM to adjust the insulin pump’s delivery automatically. 

Information from Optum electronic health record was gathered for 805 Medicaid recipients with type 1 diabetes (T1D) aged 18 to 30 years, who had had a medical encounter between 2008 and 2018, and for whom follow-up data were available for up to 2 years after the initial healthcare encounter. Pregnant patients and those diagnosed with type 2 diabetes were excluded.

Treatment modality exposures were classified based on encounter diagnosis codes. For those receiving CSII, the first record mentioning CSII was considered the date of insulin pump initiation whereas for MDI and FDI (the two groups were combined), exposure was defined by prescription codes and the date of enrollment in the study was considered the treatment start date. The primary outcome was HbA1c measures obtained at 3 to 6, 7 to 12, 13 to 18, and 19 to 24 months post assignment of the treatment modality. A secondary outcome was hospitalization for DKA.

The investigators divided patients by age into 18 to 26 years, the age at which parental insurance cover ends, and >27 years. Minorities races (Blacks, Asians, others) were grouped together as “Other races” and were compared with “Whites.” Ethnic groups were divided into “Hispanic” and “Other.” Income of <$45,000 was used to identify those of low-income status in addition to Medicaid status. Encounters with an endocrinologist were also recorded to determine if such interactions affected treatment modalities.

Of the 805 study participants, two-thirds were aged 18 to 26 years, 55% were female, 65% were White, 8.5% were Hispanic, 77% earned <$45,000 annually, and 45% were seen by an endocrinologist at least once. Only 13% of the study cohort were receiving CSII. Investigators observed differences in treatment modality based on race and endocrinologist encounter.  Patients were more likely to receive CSII if they were White (84.8%), were younger (age 18-26 years, 74.3%) and if they had been seen by an endocrinologist (66.7%). CSII was associated with improved glycemic control. The mean HbA1c on CSII was 8.0% compared with 9.5% for the MDI/FDI group at the 19-to-24–month follow-up.

There was no difference in the rate of hospitalization for DKA between CSII and MDI/FDI users over a 24-month follow-up period. Other races were 70% less likely to receive CSII than Whites (adjusted odds ratio [aOR] = 0.30, CI, 0.17-0.52). Predictors of hospitalization for DKA included male sex (aOR = 1.57, CI, 1.14-2.18), having had an encounter with an endocrinologist (aOR = 1.76, CI, 1.27-2.44), and older age (i.e., age 27 years and older, aOR = 0.57, CI, 0.40-0.82). The authors concluded that although CSII has been available for years, this has not translated into increased accessibility of this technology in minority young adults with T1D and low socioeconomic status who are on Medicaid.

As more emphasis is placed on the role of social determinants of health and their impact on clinical outcomes, pharmacists should be extra cognizant of the effect that racial disparities and low socioeconomic status have on glycemic control and should function as patient advocates whenever possible.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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