The goal of this observational study is to evaluate the predictive value of the genetic risk score for type 1 diabetes in the progression to insulin deficiency in diabetic patients. The main question it aims to answer is:
1. To investigate the predictive efficacy of the genetic risk score for T1DM in determining whether diabetic patients will progress to insulin deficiency;
2. To compare the differences in genetic characteristics between the insulin-deficient cohort and the non-insulin-deficient cohort.
This study is a nested case-control study, in which a case group and a control group are set up for the collection of observational indicators. Case group: Diabetic patients who "progressed to insulin deficiency" and those who "progressed to severe insulin deficiency". Control group: Patients who did not progress to insulin deficiency. The study period is 3 years.