A study conducted at Massachusetts General Hospital (MGH) has found that insulin production may persist for decades after the onset of type 1 diabetes. In the study, led by Denise Faustman, MD, PhD, director of the MGH Immunobiology Laboratory, blood samples from 182 individuals with type 1 diabetes were evaluated using an ultra sensitive assay (22 times more sensitive than standard assays) for C-peptide, a marker of insulin secretion, to test for residual beta cell function. The study revealed that C-peptide production can persist for decades after disease onset and remains functionally responsive to blood sugar levels. Although C-peptide levels were lower among those who had longer duration of diabetes, the decrease over time was gradual and not abrupt as traditionally believed. Even among patients with disease duration of 31 to 40 years, 10 percent still produced C-peptide.
These results contribute to a growing body of evidence suggesting there might be a longer window for therapeutic intervention in this disease. The assay offers a novel approach to identify patients, even with advanced disease, who upon glycemic stimulation may benefit from treatments to retain or enhance ?-cell function. Patients with low C-peptide levels or advanced disease should neither be uniformly excluded from clinical trials nor seen as having complete islet cell destruction.
The study results appear in the March issue of Diabetes Care.
