Decrease in Average Weekly Insulin Prescription Fills Observed During COVID-19

Ismaeel Yunusa, PharmD, PhD

Although the number of insulin prescriptions rose in the decade before the COVID-19 pandemic, reduced access to medical care and supply disruption related to the pandemic may have decreased access to insulin in US patients with diabetes.

On the other hand, emergency expansions of Medicaid may have improved access to treatment, particularly with increased capacity for telemedicine

Accordingly, a recent cross-sectional study assessed if changes to insulin prescription claims occurred during the COVID-19 pandemic, ultimately observing a considerable decrease in the average number of weekly insulin prescription fills during the pandemic period.

Methods

Led by Ismaeel Yunusa, PharmD, PhD, Department of Clinical Pharmacy and Outcomes Sciences, University of South Carolina College of Pharmacy, investigators used pharmacy claims from a 10% random sample of patients with diabetes and ≥1 insulin claim from the US VIA Longitudinal Prescription Claims (LRx) data.

The team counted the number of new and refill weekly insulin prescriptions between January 2019 - October 2020, except for the week surrounding the pandemic declaration on March 16, 2020 and weeks with national holidays, due to expected outliers in volume.

They used an interrupted time series design with segmented regression analysis to examine if the pandemic changed the number of new and existing fills in adults and children.

Additionally, the regression model worked to estimate the weekly baseline prescription counts and the 95% confidence intervals (CI) in 2019, trend before COVID-19, and changes in trend immediately following the declaration of and during the pandemic.

Findings

Data show a total of 285,343 individuals met inclusion criteria, with a mean age of 56.6 years and consisting of 51.9% women (n = 148,110).

At baseline, the average number of all existing insulin prescriptions excluding weeks with major holidays in the first week of 2019 was estimated to be 17,037.5 (95% CI, 16,728.7 - 17,346.4).

They observed the estimated number of insulin prescriptions increased significantly every week before the pandemic by 11.0 (95% CI, 2.8 - 19.3). During week 1 of the pandemic, the mean number of prescriptions decreased by -395.6 (95% CI, -933.5 to 142.4) per week.

Then, following that, a significant decrease of -55.3 (95% CI, -78.6 to -32.0) per week during the pandemic was observed, in comparison to before the pandemic.

In addition, Yunusa and colleagues found the COVID-19 pandemic was associated with a significant decrease in the estimated mean number of weekly insulin prescriptions in the adult subgroup at -54.2 (95% CI, -76.5 to -31.8), but not in the pediatric and new prescription subgroups.

Takeaways

Investigators identified potential explanations for the decline in insulin prescriptions fills during the pandemic, including reduced contact with clinicians, rationing, previous stockpiling of loss of insurance. Moreover, the lack of a substantial decline in pediatrics could be due to insulin use being more likely for pediatric type 1 diabetes.

“Although telehealth services may have reduced care disruption, it may not have led to more insulin prescription fills,” investigators wrote.

The study, “Trends in Insulin Prescribing for Patients With Diabetes During the COVID-19 Pandemic in the US,” was published in JAMA Network Open.