Low levels of C‐peptide have clinical significance for established Type 1 diabetes. Issue 10 (16th August 2015)

• Record Type: Journal Article
• Authors: Kuhtreiber, W. M.; Washer, S. L. L.; Hsu, E.; Zhao, M.; Reinhold, P.; Burger, D.; Zheng, H.; Faustman, D. L.
• Is Part Of: Diabetic medicine. Volume 32:Issue 10(2015:Oct.)
• Page Start: 1346
• Page End: 1353
• Publication Date: 2015-08-16
• Subjects: Diabetes -- Periodicals; 616.462
• DOI: 10.1111/dme.12850
• Languages: English
• ISSNs: 0742-3071

Abstract

<abstract abstract-type="main" id="dme12850-abs-0001"> <title>Abstract</title> <sec id="dme12850-sec-0001" sec-type="section"> <title>Aim</title> <p>To determine whether the low C‐peptide levels (< 50 pmol/l) produced by the pancreas for decades after onset of Type 1 diabetes have clinical significance.</p> </sec> <sec id="dme12850-sec-0002" sec-type="section"> <title>Methods</title> <p>We evaluated fasting C‐peptide levels, duration of disease and age of onset in a large cross‐sectional series (<italic>n </italic>=<italic> </italic>1272) of people with Type 1 diabetes. We then expanded the scope of the study to include the relationship between C‐peptide and HbA<sub>1c</sub> control (<italic>n </italic>=<italic> </italic>1273), as well as diabetic complications (<italic>n </italic>=<italic> </italic>324) and presence of hypoglycaemia (<italic>n </italic>=<italic> </italic>323). The full range of C‐peptide levels was also compared with 1, 5‐Anhydroglucitol, a glucose responsive marker.</p> </sec> <sec id="dme12850-sec-0003" sec-type="section"> <title>Results</title> <p>C‐peptide levels declined for decades after diagnosis, and the rate of decline was significantly related to age of onset (<italic>P </italic><<italic> </italic>0.0001), after adjusting for disease duration. C‐peptide levels > 10 pmol/l were associated with protection from complications (e.g. nephropathy, neuropathy, foot ulcers and retinopathy; <italic>P </italic>=<italic> </italic>0.03). Low C‐peptide levels were associated with poor metabolic control measured by HbA<sub>1c</sub> (<italic>P </italic><<italic> </italic>0.0001). Severe hypoglycaemia was associated with the lowest C‐peptide levels compared with mild (<italic>P </italic>=<italic> </italic>0.049) or moderate (<italic>P </italic>=<italic> </italic>0.04) hypoglycaemia. All levels of measurable C‐peptide were responsive to acute fluctuations in blood glucose levels as assessed by 1, 5‐Anhydroglucitol (<italic>P </italic><<italic> </italic>0.0001).</p> </sec> <sec id="dme12850-sec-0004" sec-type="section"> <title>Conclusions</title> <p>Low C‐peptide levels have clinical significance and appear helpful in characterizing groups at‐risk for faster C‐peptide decline, complications, poorer metabolic control and severe hypoglycaemia. Low C‐peptide levels may be a biomarker for characterizing at‐risk patients with Type 1 diabetes.</p> </sec> </abstract>