AIMS: Dipeptidyl-peptidase 4 inhibitors have become one of the most popular antidiabetic drugs. However, what kind of combinations with other drugs were advantageous was not known. Here, we tried to elucidate it in a real-life clinical setting. METHODS: We retrospectively studied efficacies of sitagliptin in 87 Japanese patients with type 2 diabetes mellitus for 52 weeks. We divided subjects into excellent, effective and unresponsive subgroups according to glycemic responses to sitagliptin. RESULTS: In the excellent and effective groups the minimum HbA1c values were attained at 16 weeks while HbA1c levels in the unresponsive group kept increasing during the study period. There was a significant difference in the baseline HbA1c values between the excellent and unresponsive groups (p=0.02). Interestingly, the mean doses of pioglitazone were highest in the excellent group and lowest in the unresponsive group (p=0.02). When we compared the effective and unresponsive groups, the mean doses of sulfonylureas were constantly higher in the effective group than in the unresponsive group (p=0.05). CONCLUSIONS: These data suggest that the baseline HbA1c value can be a factor that predicts the extent of HbA1c reduction and reveal a possibility that the concomitant use of pioglitazone augments glycemic responsiveness to sitagliptin.
AIMS: Dipeptidyl-peptidase 4 inhibitors have become one of the most popular antidiabetic drugs. However, what kind of combinations with other drugs were advantageous was not known. Here, we tried to elucidate it in a real-life clinical setting. METHODS: We retrospectively studied efficacies of sitagliptin in 87 Japanese patients with type 2 diabetes mellitus for 52 weeks. We divided subjects into excellent, effective and unresponsive subgroups according to glycemic responses to sitagliptin. RESULTS: In the excellent and effective groups the minimum HbA1c values were attained at 16 weeks while HbA1c levels in the unresponsive group kept increasing during the study period. There was a significant difference in the baseline HbA1c values between the excellent and unresponsive groups (p=0.02). Interestingly, the mean doses of pioglitazone were highest in the excellent group and lowest in the unresponsive group (p=0.02). When we compared the effective and unresponsive groups, the mean doses of sulfonylureas were constantly higher in the effective group than in the unresponsive group (p=0.05). CONCLUSIONS: These data suggest that the baseline HbA1c value can be a factor that predicts the extent of HbA1c reduction and reveal a possibility that the concomitant use of pioglitazone augments glycemic responsiveness to sitagliptin.