Trends in antidiabetic medical treatment from 2005 to 2014 in Taiwan

Several new antidiabetic drugs have been introduced in Taiwan. However, the trends in antidiabetic treatment remain unexamined. We studied data from the Taiwan National Health Insurance Database to identify outpatient prescriptions for antidiabetic drugs from 2005 to 2014. The patterns in antidiabetic treatment and the number of different classes of antidiabetic drugs were analyzed. The proportions of prescriptions of antidiabetic monotherapy, combination therapy, or insulin therapy were further analyzed. The total and mean prescriptions gradually increased during the study period. Prescription of oral antidiabetic drugs (OADs) only or insulin-only therapy decreased slightly. Prescriptions of monotherapy and dual therapy decreased, whereas those of triple or higher order combinations increased. Prescriptions of sulfonylureas (SUs) decreased, whereas those of metformin and dipeptidyl peptidease-4 (DPP4) inhibitors increased. Insulin prescriptions increased but accounted for only 13.07% of prescriptions in 2014. Among monotherapy prescriptions, SU prescriptions decreased, but metformin and DPP4 inhibitor prescriptions increased. Among dual OAD prescriptions, those including SUs decreased, and those of metformin and DPP4 inhibitors increased. Although prescriptions of the metformin–SU combination decreased, they remained the most common among all dual OAD prescriptions, followed by the metformin–DPP4 inhibitor combination. Prescriptions of human insulin decreased and those of insulin analogs increased considerably; those of basal insulin increased, and those of mixed insulin decreased. However, mixed insulin was prescribed more than basal–bolus insulin. Antidiabetic treatment has become complex in Taiwan. Although combination therapy would become the major treatment strategy gradually, the underuse of insulin therapy must improve.