Serum Chitinase-3-Like Protein 1 (CHI3L1/YKL-40) is Associated with Diabetic Nephropathy But Not with Glycemic Control or Glucose Variability in Patients with Type 1 Diabetes

Background and aim: In this study we aimed to assessed serum levels of chitinase-3 like-protein-1 (CHI3L1), also known as YKL-40, in patients with type 1 diabetes depending on the presence of complications, glycemic control and glucose variability. Materials and Methods: Fifty seven subjects with type 1 diabetes and 19 individuals with normal glucose tolerance (control group) were included. Continuous glucose monitoring was performed in all patients with assessment of time in ranges and glucose variability parameters. Serum concentrations of CHI3LI/YKL40 were measured by magnetic bead assay. Results: Subjects with type 1 diabetes demonstrated no significant changes in CHI3L1/YKL-40 levels compared to control (
$\mathrm{p}=0.84$
). Patients with diabetic nephropathy when compared to those without had significantly higher CHI3L1/YKL-40 concentrations (
$\mathrm{p}=0.037$
). CHI3L1/YKL-40 demonstrated weak correlations with serum creatinine (
$\mathrm{r}=0.33, \mathrm{p}=0.01$
) and estimated glomerular filtration rate
$(\mathrm{r}=-0.29, \mathrm{p}=0.03)$
but not with urinary albumin-to-creatinine ratio. No associations were found between CHI3L1/YKL-40 level and HbA1c, time in ranges, and glucose variability parameters. Conclusions: Serum levels of CHI3L1/YKL-40 in patients with type 1 diabetes is associated with diabetic nephropathy but not with glycemic control and glucose variability.