Assessing the Rising Prevalence of Early-onset Type 2 Diabetes in the US
A recent analysis of data from the National Health adn Nutrition Examination Survey (NHANES) reveals a concerning increase in the prevalence of early-onset Type 2 Diabetes (T2D) in the United States between 1999 and 2020.The findings, published in Diabetes Ther on September 16, 2025 (Lee CJ, et al., doi:10.1007/s13300-025-01788-7), highlight a growing need for thorough policies and care strategies addressing both the medical and financial challenges associated with the disease.
Researchers retrospectively examined NHANES data – a series of nationally representative, cross-sectional surveys – focusing on individuals under age 40 with diagnosed or undiagnosed T2D to track prevalence trends. Early-onset T2D was defined by either a self-reported physician diagnosis or laboratory evidence indicating undiagnosed diabetes.
the analysis showed a rise in both diagnosed and undiagnosed cases. Diagnosed early-onset T2D increased from a meen of 1.42% (SE 0.19) in 1999-2000 to 1.72% (SE 0.24) in 2017-2020. Simultaneously, undiagnosed cases doubled over the same period, rising from 0.18% (SE 0.09) to 0.35% (SE 0.06).
Individuals diagnosed with early-onset T2D differed significantly from those diagnosed after age 40. They were more likely to identify as Hispanic, be uninsured, and have a lower poverty-income ratio. Conversely, they were less likely to be non-Hispanic White or have private or Medicare insurance coverage (all P* < .05).
Clinically, the early-onset group exhibited a less favorable cardiometabolic profile, with higher mean glycated hemoglobin, Homeostatic Model Assessment for Insulin Resistance scores, fasting insulin and glucose levels, body mass index, and waist circumference. interestingly, despite these elevated risk factors, individuals with early-onset T2D were less likely to have established comorbidities like heart failure, coronary heart disease, stroke, chronic kidney disease, or cancer (all *P < .05), even when accounting for disease duration.
The researchers acknowledged limitations inherent in the study design. The cross-sectional nature of NHANES data prevented evaluation of causal relationships regarding disease progression or comorbidity advancement. Reliance on self-reported information introduced potential recall bias, and the exclusion of institutionalized populations may limit the generalizability of the findings. Furthermore, data collection in 2-3 year cycles meant that finer temporal changes were not captured.
Despite these limitations,the study reinforces the urgency of earlier detection and targeted interventions,notably for underserved populations. As the researchers concluded, the prevalence of undiagnosed early-onset T2D is increasing in the US, disproportionately affecting Hispanic and non-Hispanic Black individuals, and also those facing socioeconomic challenges (Steinzo P, AJMC, August 4, 2025. Accessed September 16, 2025. https://www.ajmc.com/view/type-2-diabetes-linked-to-poor-credit-financial-distress).
