Imagine identifying type 2 diabetes risk years before prediabetes even appears—using a simple score in completely normal patients. A groundbreaking new study published in the Diabetes & Metabolic Syndrome proves insulin resistance strikes early, well before hyperglycemia, and offers a practical tool to catch progressors in time.
Study Tracks 16,000+ Normoglycemic Adults Over 3 Years
Researchers followed 16,333 normoglycemic adults (median age 43, 31% men) from a nationwide employer health program starting August 2020, with nearly 3 years of median follow-up. They calculated the insulin resistance risk score (IRRS) from fasting intact insulin and C-peptide levels. The low tertile scored under 8%, while top tertile exceeded 20%. Incident prediabetes or T2D was rigorously defined: fasting glucose ≥100 mg/dL, HbA1c ≥5.7%, or physician-diagnosed T2D.
Progressors Show Skyrocketing IRRS Across All BMIs
IRRS was consistently higher in those progressing to prediabetes or T2D versus non-progressors, regardless of BMI. Top tertile participants faced 43% greater risk (adjusted HR 1.43, 95% CI 1.31-1.57, P<0.001) even after controlling for age, sex, BMI, and HbA1c. Non-progressors stayed low-risk throughout, while Diabetes Prevention Program long-term data reinforces most at-risk patients eventually reach T2D.
Game-Changer for T2D Prevention in Clinic
This positions IRRS as a clinician-friendly marker to stratify normoglycemic patients of any BMI for early intervention. Routine testing could transform diabetes prevention, spotting insulin resistance before traditional markers light up. It is a potentially useful approach for at-risk patients.