Correlation between Serum 25-Hydroxyvitamin D3 and Abnormal Insulin Secretion in Patients with Type 2 Diabetes Mellitus

To investigate the correlation between serum 25-hydroxyvitamin D3 and abnormal insulin secretion in patients with type 2 diabetes mellitus. Eight type 2 diabetes mellitus patients treated from January 2018 to November 2020 (observation group) and another 80 healthy volunteers receiving physical examination in the same period (control group) were included. Fasting venous blood sample was collected to detect serum 25-hydroxyvitamin D3, fasting blood glucose, glycosylated hemoglobin, fasting insulin, insulin resistance index and insulin secretion index. According to insulin secretion index, observation group was divided into normal and abnormal insulin secretion groups and their serum 25-hydroxyvitamin D3, fasting blood glucose, glycosylated hemoglobin, fasting insulin and insulin resistance index were compared. Based on serum 25-hydroxyvitamin D3 level, observation group was divided into serum 25-hydroxyvitamin D3 positive and negative groups and their fasting blood glucose, glycosylated hemoglobin, fasting insulin, insulin resistance index and insulin secretion index were compared. The correlations of serum 25-hydroxyvitamin D3 with fasting blood glucose, glycosylated hemoglobin, fasting insulin, insulin resistance index and insulin secretion index were analyzed. Observation group had lower serum 25-hydroxyvitamin D3 level and insulin secretion index and higher fasting blood glucose, glycosylated hemoglobin, fasting insulin and insulin resistance index than those of control group (p<0.05). Abnormal insulin secretion group had lower serum 25-hydroxyvitamin D3 level and higher fasting blood glucose, fasting insulin and insulin resistance index than those of normal insulin secretion group (p<0.05). Serum 25-hydroxyvitamin D3 positive group had higher fasting blood glucose, glycosylated hemoglobin, fasting insulin and insulin resistance index and lower insulin secretion index than those of serum 25-hydroxyvitamin D3 negative group (p<0.05). Serum 25-hydroxyvitamin D3 was negatively correlated with fasting blood glucose, glycosylated hemoglobin, fasting insulin and insulin resistance index, but positively correlated with insulin secretion index. In type 2 diabetes mellitus patients, the expression of serum 25-hydroxyvitamin D3 is down-regulated, which is closely related to abnormal insulin secretion. Serum 25-hydroxyvitamin D3 can be used to determine the insulin secretion function of type 2 diabetes mellitus patients.