Most with long-term diagnosis foud to continue to secrete low levels of insulin…
In a large-population based study, researchers used sensitive C-peptide assays to demonstrate that 43-74% people with longstanding (>5 years) type 1 diabetes are microsecretors of endogenous insulin with C-peptide levels.
The Scottish researchers measured the occurrence of visible endogenous C-peptide levels using urine C-peptide-to-creatinine ratio (UCPCR) in a large, nonselected, population-based study of type 1 diabetes and to measure any potential clinical associations. A total of 924 patients from primary and secondary care in two U.K. centers were included.
- Clinical diagnosis of type 1 diabetes and must be <30 years of age when they received a diagnosis
- Had a diabetes duration of >5 years
- 97% participants were white Europeans
- Young-onset type 2 diabetes, patients with a UCPCR of ≥nmol/mmol who were GAD and IA2 autoantibody negative
- BMI >30 kg/m2
- The results demonstrated that occurrence of a visible C-peptide level was inversely associated with a shorter duration of diabetes but was not shown to have any association in age at diagnosis or BMI.
- 80% of participants (740 of 924 participants [95% CI 77-83%]) shown detectable C-peptide levels (UCPCR >0.001 nmol/mmol).
- 52% of participants (483 of 924 patients [49-55%]) shown a UCPCR between 0.001 and 0.03 nmol/mmol.
- 20% of participants (187 of 924 participants [18-23%]) shown a UCPCR between 0.03 and 0.2 nmol/mmol.
- 8% (70 of 924 participants [6-9%]) shown a UCPCR ≥0.2 nmol/mmol.
The authors concluded that by using UCPCRs, 80% of participants demonstrated detectable endogenous C-peptide levels during the study. The results from this study provide strong evidence that absolute beta cell deficiency does not occur in most people with type 1 diabetes.
- Most people with type 1 diabetes do not completely lose beta cells function and continue to secrete low levels of insulin.
- The occurrence of a visible C-peptide level was not associated with age at diagnosis or BMI.
- More studies are necessary to support the evidence for a future treatment of type 1 diabetes.
Oram RA, McDonald TJ, Shields MG, et al. Most People With Long-Duration Type 1 Diabetes in a Large Population-Based Study Are Insulin Microsecretors. Diabetes Care. 2015; 38:323-328.