Insulin Analogs, Pen Delivery Devices Most Used Among Patients With T2D

Using data from a nationally representative sample, investigators sought to determine trends in insulin device use.

In the past 5 years, ambulatory insulin use among patients with type 2 diabetes (T2D) was dominated by insulin analogs and pen delivery devices, according to results of a serial cross-sectional study. However, findings also showed that between 2016 and 2020, there was an increase in uptake of newer delivery products as they were brought to market.

Although insulin was discovered 100 years ago, currently available human insulins were only first approved by the FDA in 1982. “However, little is known regarding recent patterns of insulin use in the United States,” researchers wrote, noting this knowledge can better inform health policy and public health initiatives.

Using the Health National Disease and Therapeutic Index (NDTI; IQVIA)—a comprehensive and nationally representative all-payer audit of outpatient care in the United States—the investigators characterized trends in ambulatory use of insulin between January 2016 and December 2020.

All individuals included in the study had T2D and were 35 years or older; all medications that contained insulin were included in the analyses. “The data collected are projected, and sample weights were applied to create estimates for the US population, accounting for the stratified cluster sampling,” the authors added.

A total of 27,860,691 insulin treatment visits were reported within the study timeframe. Of the patient encounters that indicated insulin use in 2020, 43.9% were among those aged 60 to 74, 52.4% were among men, 58.4% were among White patients, 17.9% were among Black patients, and 15.5% were among Hispanic patients.

Analyses revealed:

  • Insulin glargine was the most frequently used insulin from 2016 to 2020, accounting for approximately half of treatment visits
  • Among insulin classes, long-acting insulin accounted for approximately two-thirds of treatment visits during this period
  • Treatment visits for insulin pens increased from 36.1% in 2016 to 58.7% in 2020, while use of insulin vials/syringes declined in parallel
  • Analog insulin use predominated and accounted for more than 80% of total treatment visits across all years

In 2016, newer insulins were used in 18.1% of total treatment visits and rose in prominence to 40.9% in 2020. In addition, “the use of biosimilar insulin, which was first approved in 2015, increased from 2.6% in 2017 to 8.2% in 2020 of total insulin treatment visits,” while “the total number of insulin treatment visits declined from a peak of 6 million visits in 2016 to a nadir of 4.9 million visits in 2020 (approximately 18% decline).”

Data showed the total number of treatment visits for insulin was at its lowest in 2020. This reduction could have been due to the overall decrease in health care utilization seen in 2020 as a result of the COVID-19 pandemic. However, the researchers were unable to determine if this decrease resulted from fewer overall encounters between patients and physicians or patients’ home insulin use.

Furthermore, “insulin glargine’s continued predominance, relative to newer insulins, may be due to several factors, including clinical inertia, which has been commonly described in the treatment of patients with T2D,” the authors hypothesized. The lack of available insulin biosimilars may have also contributed to this trend, although between 2017 and 2020, biosimilar insulin use increased by over 200%.

A lack of information regarding whether the use of insulin was adhering to current guidelines marks a limitation to this study. The database also did not include information on care delivery occurring in jails, prisons, or other institutional settings.

“An in-depth understanding of recent trends in use of insulin may provide insight into the drivers of insulin cost, although cost was not addressed in this study,” the researchers concluded. “These findings are of broad relevance to patients, clinicians, and policy makers invested in improving access to and affordability of insulins in the United States.”


Sarkar S, Heyward J, Alexander GC, Kalyani RR. Trends in insulin types and devices used by adults with type 2 diabetes in the United States, 2016-2020. JAMA Netw Open. Published online October 12, 2021. doi:10.1001/jamanetworkopen.2021.28782