Type 1 and Type 2 Diabetes Incidence Increased During COVID-19 Pandemic

Matthew Mefford, PhD
Credit: Kaiser Permanente Research

Results of a new study from investigators at Kaiser Permanente Southern California offers an overview of changes in incidence of diabetes among younger patient populations before and during the COVID-19 pandemic.

An analysis of age- and sex-standardized incidence rates from 2016-2021, results of the study suggest rates of both type 1 diabetes and type 2 diabetes increased during the COVID-19 pandemic relative to prepandemic periods, with non-Hispanic Black and Hispanic youth the most adversely affected by this trend.

“Incidence rates of both type 1 diabetes and type 2 diabetes increased during the COVID-19 pandemic compared with before. Increases were observed overall and within specific strata of age, in particular, those aged 10 to 19 years, male individuals, and among some racial and ethnic groups,” wrote investigators.¹

In the early stages of the COVID-19 pandemic, reports began to emerge documenting increased prevalence of both type 1 diabetes and type 2 diabetes among adolescent populations. A pair of studies from investigators at the Duke Clinical Research Institute concluded incident cases of type 1 diabetes increased by 48% from 2019-2020 while incident cases of type 2 diabetes increased by 231% from 2019-2020. The second study provided further evidence of this trend, suggesting incident cases of type 1 diabetes increased by 48% and incident cases of type 2 diabetes increased by 188% in 2021-2022 relative to incidence in prepandemic periods.²

In the current study, a team led by Matthew Mefford, PhD, cardiovascular disease epidemiologist and research scientist in the Department of Research and Evaluation of Kaiser Permanente Southern California, sought to contribute to the existing knowledge base on the subject by estimating changes in diabetes incidence rate among patients within the Kaiser Permanent Southern California healthcare system, which investigators purport contains data related to more than 20% of all residents southern California.¹

For the purpose of analysis, annual cohorts for determining diabetes incidence were created throughout the identification of patients aged younger than 20 years on December 31 of each year during the study period. In addition to those aged less than 1 year, investigators also excluded those with less than 1 day of enrollment in the health plan the 12 months prior to their incidence year or if they had evidence of diabetes at any time prior to the incidence year.¹

Investigators defined incident diabetes as meeting any of 4 criteria within a 12-month period:¹

• 2 or more outpatient diagnoses of diabetes on separate days in any position
• 1 or more outpatient diabetes diagnoses and 1 or more outpatient prescriptions for a diabetes medication
• 1 or more outpatient diabetes diagnosis and 2 or more outpatient abnormal laboratory results indicative of diabetes
• 1 or more inpatient primary discharge diagnoses for diabetes and 1 or more outpatient indicators of diabetes.

Specific covariates used in the investigators’ analysis were age, sex, and race and ethnicity, body mass index, laboratory results, and health care utilization.¹

Overall, the total population of eligible individuals in each year ranged from 979,710 in 2016 to 1,028,997 in 2021. From 2016-2021, investigators identified 1200, 1100, and 63 patients with type 1 diabetes, type 2 diabetes, and other diabetes, respectively.¹

Those with incident type 1 diabetes had a mean age of 11 (Standard deviation [SD], 4.5) years, 62.7% were aged 10-19, 52.3% were males, and 36.4% were non-Hispanic White individuals. Those with incident type 2 diabetes had a mean age of 15.7 (SD, 2.7) years, 98.4% were aged 10-19 years, 46.9% were males, and 7.5% were non-Hispanic White individuals.¹

Upon analysis, results suggested the age- and sex-standardized incidence rates of type 1 diabetes increased from 19.55 (95% CI, 16.79-22.31) per 100,000 person-years in 2016 to 24.27 (95% CI, 21.27-27.28) per 100,000 person-years in 2021. A similar trend was observed for type 2 diabetes, with incident rates increasing from 15.66 (95% CI, 13.25-18.08) per 100,000 person-years in 2016 to 29.44 (95% CI, 26.19-32.69) per 100,000 person-years in 2021.¹

When assessing patient subgroups with a greater risk of developing incident type 1 diabetes, results suggested those aged 10-19 years, male individuals, and Hispanic individuals experienced an elevated incidence rate ratio. For type 2 diabetes, those aged 10-19 years and those with Black, Hispanic, and other/unknown race and ethnicity experienced an elevated incidence rate ratio.¹

“In this cohort study of youth in [Kaiser Permanente Southern California], incidence of diabetes increased during the COVID-19 pandemic and was more pronounced in specific racial and ethnic groups. Future research to understand differential impacts of physiologic and behavioral risk factors is warranted,” investigators concluded.¹

References:

1. Mefford MT, Wei R, Lustigova E, Martin JP, Reynolds K. Incidence of Diabetes Among Youth Before and During the COVID-19 Pandemic. JAMA Netw Open. 2023;6(9):e2334953. doi:10.1001/jamanetworkopen.2023.34953
2. Campbell P. Rise in pediatric diabetes cases continued through year 2 of covid-19 pandemic. HCP Live. July 18, 2023. Accessed September 21, 2023. https://www.hcplive.com/view/rise-in-pediatric-diabetes-cases-continued-through-year-2-of-covid-19-pandemic.