Glycemic control among U.S. adults with diabetes may have worsened from 2021 to 2023, with young adults experiencing a decline from 57.4% to 37.1%, a trend associated with increased cardiovascular risk, according to a recent research letter. 

Investigators assessed trends in diabetes prevalence and glycemic control among U.S. adults from 2013 to 2023. They analyzed data from the National Health and Nutrition Examination Survey, a nationally representative survey of noninstitutionalized adults, to evaluate diabetes prevalence and glycemic control across age and sex subgroups.

In the research letter, published in JAMA, the investigators included 24,263 adults (weighted mean age = 48.5 years, 51.4% female), 4,623 of whom had diabetes. Diabetes was defined as a hemoglobin A_1c (HbA_1c) level of at least 6.5%, fasting plasma glucose of at least 126 mg/dL, or a health care diagnosis. Glycemic control was classified as an HbA_1c level below 7.0%. Prevalence estimates were standardized to the 2010 U.S. Census population, and multivariable regression analyses were performed to assess trends over time.

Between 2013 and 2023, diabetes prevalence remained stable, increasing slightly from 12.8% (95% confidence interval [CI] = 11.8%–13.9%) between 2013 and 2014 to 14.1% (95% CI = 12.7%–15.4%) between 2021 and 2023 (P = .25). Among adults with diagnosed diabetes (77%, n = 3,541), mean HbA_1c levels were stable from 2013 to 2014 and 2017 to 2020 (P = .37) but increased significantly from 7.31% (95% CI = 7.15%–7.48%) between 2017 and 2020 to 7.60% (95% CI = 7.44%–7.76%) between 2021 and 2023 (P = .03). Similarly, glycemic control rates declined from 54.3% (95% CI = 46.9%–61.7%) between 2017 and 2020 to 43.5% (95% CI = 38.5%–48.5%) between 2021 and 2023 (P = .02).

These trends were most pronounced among young adults aged 20 to 44 years, where mean HbA_1c increased from 7.43% (95% CI = 6.94%–7.92%) between 2017 and 2020 to 8.51% (95% CI = 7.86%–9.16%) between 2021 and 2023 (P = .03). Glycemic control rates in this subgroup declined from 57.4% (95% CI = 46.1%–68.7%) between 2017 and 2020 to 37.1% (95% CI = 26.9%–47.3%) between 2021 and 2023 (P = .006). No statistically significant changes were observed among older adults or across sex subgroups.

The investigators, led by Kosuke Inoue, MD, PhD, of the Richard A. and Susan F. Smith Center for Outcomes Research at the Beth Israel Deaconess Medical Center, noted that pandemic-related factors, including reduced health care access, increased sedentary behavior, and heightened mental health stressors, may have contributed to worsening glycemic control, particularly in younger adults. Study limitations included low response rates in the 2021 to 2023 study period, changes in racial and ethnic sampling, and the lack of data on diabetes medication use. Since poor glycemic control is associated with increased cardiovascular risk, these findings suggested a need for continued efforts to improve diabetes management, particularly among younger populations.

Full disclosures can be found in the published letter.