Adolescent Hyperglycemia in Type 1 Diabetes May Increase Adult Neuropathy Risk

Poor blood sugar control in adolescent patients with type 1 diabetes (T1D) may be associated with a higher risk of neuropathy in adulthood, according to recent research from the University of Michigan.1

Peripheral neuropathy is one of the most common complications of both types of diabetes, affecting ≤50% of all patients with diabetes during their disease. An additional 30-40% of patients also experience neuropathic pain. Given these statistics, prior studies have shown that an average of 1 in 5 patients with diabetes develops painful neuropathy.2

“This unique study emphasizes the importance of supporting teenagers with type 1 diabetes to manage their blood sugar well and ensure a smooth transition to adult care to prevent future complications,” Eva Feldman, MD, PhD, director of the ALS Center of Excellence at the University of Michigan Health and senior author of the study, said in a statement.1

The study included children diagnosed with T1D between 1990-1992 who were recruited into the Cognition and Longitudinal Assessment of Risk Factors over 30 Years cohort study in Australia. Investigators collected HbA1c from medical records, and microvascular complications were assessed through self-reports, clinical screenings, retinal photographs, and urinary albumin-creatinine testing.3

A total of 30 children were recruited from the original cohort with a mean diagnosis age of 2.9 years. After an average of 29.7 years (standard deviation [SD]: 3.9 years), 33% of participants (n = 13) developed neuropathy, 63% (n = 19) developed diabetes-related eye disease, and 10% (n = 3) developed neuropathy.3

Mean HbA1c estimates during adolescence (9% [74.9 mmol/mol]; 95% CI, 8.6-9.3 [70.5-78.1]) were substantially higher than childhood (8.2% [66.1 mmol/mol]; 95% CI, 7.8-8.5 [61.7-69.4]; P <.001) and adulthood (8.2% [66.1 mmol/mol]; 95% CI, 7.8-8.5 [61.7-69.4]). Investigators also noted a significant association between greater deviation from mean childhood HbA1c and increased neuropathy risk (RRR, 7.8; 95% CI, 1.1-57.4; P = .009), but not retinopathy or nephropathy (P ≥.06).3

Ultimately, although they noted other potential influences for future complication risks, investigators determined that adolescent hyperglycemia leads to higher neuropathy risk in adulthood, regardless of preexisting childhood control. The team urges adolescent glycemic management, noting that patients with adolescent hyperglycemia may require more support in transitioning to adult care.3

“While clear links between glycemia and neuropathy have been found in type 1 diabetes, we know there are also vascular risk factors that play a key role in the development of neuropathy,” Kara Mizokami-Stout, MD, MSc, an assistant professor of metabolism, endocrinology, and diabetes at the University of Michigan Medical School, said in a statement. “However, this study does underscore the need to maximize our support for younger individuals with diabetes.”1

References

1. Michigan Medicine. Diabetic teens with high blood sugar have higher neuropathy risk in adulthood. Eurekalert! October 9, 2025. Accessed October 9, 2025. https://www.eurekalert.org/news-releases/1101259

2. Jensen TS, Karlsson P, Gylfadottir SS, et al. Painful and non-painful diabetic neuropathy, diagnostic challenges and implications for future management. Brain. 2021;144(6):1632-1645. doi:10.1093/brain/awab079

3. Moran C, Collyer TA, Brown A, et al. Associations between HbA1c and complications in children diagnosed with type 1 diabetes before age 6: A 30-year follow-up study. Diabetes Research and Clinical Practice. 2025;228:112447. doi:10.1016/j.diabres.2025.112447