Demographics of study subjects according to their drug using status.

a. Diagnosed type 2 diabetes mellitus (T2DM) patients who did not use statin before the end of follow up date.b. The statin regular user is the patient who uses statin continuously at least over one year in the follow up time that nearby 2 statin prescriptions can't exceed 120 days.This group of diagnosed T2DM patients is statin regular user group.c. Wilcoxon rank sum test or Pearson's Chi-square test.d. The case number is calculated before patient's index date.The index date of patient who never uses statin before the end of follow up date is the T2DM diagnosed date.The index date of patient who is statin regular user is the date of staring to take statin regularly.e. The case number is the regular use of statin after patient's T2DM diagnosed date.f. The case number is the regular use of the anti-diabetic drug before patient's index date.g. Charlson comorbidity index (CCI): The diagnoses recorded in the National Health Insurance Research Database before the index date is used to calculate CCI score.We exclude the diagnosis of diabetes mellitus and stroke from CCI score calculation, because these two disease entities are considered separately.