Risk Factors for Diabetic Peripheral Neuropathy in Adolescents and Young Adults With Type 2 Diabetes: Results From the TODAY Study
Research Design and Methods: The Michigan Neuropathy Screening Instrument (MNSI) and a 10-gram monofilament exam were performed annually. DPN was defined as a score (>2) on the MNSI-exam or combined MNSI-exam and MNSI-survey scores (exam >2 and/or survey ≥4), or monofilament (<8/10 correct responses) at 2 or more consecutive visits. Multivariable time-to-event models assessed the association of risk factors evaluated longitudinally with DPN events.
Results: 674 participants (35% male), with mean age 14 years and diabetes duration <2 years at study entry were evaluated annually over an average of 10.2 years. Males had a significantly higher cumulative incidence of DPN than females (38.5% vs. 27.2% via MNSI-exam, p=0.002; 14.0% vs. 5.1% via monofilament, p=0.01). Rates did not differ by race-ethnicity. Higher HbA1c and BMI were associated with higher DPN, by both MNSI and monofilament. In multivariable models, male sex, older age, and higher BMI were associated with MNSI-exam DPN risk.
Conclusions: DPN was evident early in the course of youth-onset type 2 diabetes and increased over time. It was higher in males and related to glycemic control. These findings raise concern for long-term development of neuropathy-related morbidity in youth with type 2 diabetes and the need to achieve improved glycemic control.