Plasma copeptin in children and adolescents with type 1 diabetes mellitus in comparison to healthy controls

Abstract

In a cohort of children and adolescents with type 1 diabetes mellitus the trial tested the hypothesis that copeptin levels are associated with kidney function, biometrical data and quality of diabetes control. Patients and methodsA total of 141 subjects were recruited to participate in the trial: 80 patients with type 1 diabetes (13.0±3.4years, HbA1c 7.85±1.42%) and 61 healthy controls (12.4±2.8years). Clinical and socio-economic data were assessed. A sandwich immunoassay (B.R.A.H.M.S. GmbH/Thermo Fisher Scientific, Hennigsdorf/Berlin, Germany) was used for measuring plasma copeptin levels. ResultsThe mean concentration of copeptin in the diabetic patients was 4.75±3.46pmol/l. There was a strong inverse correlation between copeptin and GFR (r=−0.86, p=0.021), as well as with total cholesterol (r=−0.23, p=0.041), LDL-cholesterol (r=−0.24, p=0.036), but not with serum creatinine, albuminuria, HbA1c, blood glucose, MAGE, CRP, systolic or diastolic blood pressure or age, diabetes duration, weight, height and BMI. Comparing patients with a diabetes duration of ⩾7years (n=45) with those with a diabetes duration <7years (n=35), patients with a longer duration of diabetes had higher copeptin levels (5.24±2.26 vs 4.13±2.86, p=0.045). Performing multivariate analyses only GFR could be identified as a parameter associated with copeptin (R-square=0.05, β=−0.23, p=0.032). In the healthy controls mean copeptin concentration was 5.56±3.15pmol/l. The copeptin concentration and GFR were inversely correlated as well (r=−0.61, p=0.034). However, other correlation and multivariate analyses revealed no further significant results. Comparing patients with type 1 diabetes mellitus with the healthy controls, the diabetes patients revealed no significant difference with respect to copeptin (p=0.24), serum creatinine (49.8±11.9 vs 50.4±11.0μmol/l, p=0.53) or GFR (102.4±23.3 vs 104.5±19.1ml/min, p=0.47). On the other hand, patients with type 1 diabetes had lower concentrations of CRP (1.66±3.91 vs 3.21±3.04μg/ml, p=0,013), triglycerides (0.88±0.53 vs 1.13±0.60mmol/l, p=0.010), and a lower ratio of LDL-/HLD-cholesterol (1.73±0.69 vs 2.32±0.80, p<0.001), as well as lower body weight (51.3±18.0 vs 60.3±15.7kg, p=0.002) and BMI (19.7±3.8 vs 23.2±2.9kg/m2, p<0.001). In contrast to the controls, the diabetes patients had higher blood glucose levels at the time of examination (8.2±3.8 vs 4.7±0.5mmol/l, p<0.001), higher HDL-cholesterol levels (1.59±0.34 vs 1.26±0.24mmol/l, p<0.001), as well as higher education and higher educational levels of the mothers. ConclusionsThe present trial revealed a clear association between GFR and copeptin in children and adolescents with type 1 diabetes mellitus. Hence, copeptin can be considered as a marker of renal function.