[Post-hoc analyses of type 2 diabetes patients switch from premixed insulin regimen to basal insulin plus oral hypoglycemic agents regimen].

OBJECTIVE: To compare characteristics of better responders to new regimen therapy with non-responders.

METHODS: In a 12-week, two-center, open, parallel group clinical trial, 80 type 2 diabetic patients treated with twice-daily premixed 30 R insulin with or without OAD (s) [fasting blood glucose (FBG) 7.8 - 16.7 mmol/L, HbA1c 7% - 10%] were randomized to once-daily morning insulin glargine plus glimepiride 3 mg or premixed 30 R insulin (70/30) twice-daily plus glimepiride 3 mg. Insulin dosage was titrated to target FBG
RESULTS: Mean HbA1c reduction from baseline were similar in glargine group and premixed insulin group (8.8%-->8.0% vs 8.9%-->7.8%, P > 0.05). However, hypoglycemic episodes were significantly higher in premixed-insulin-treated subjects than in glargine-treated subjects [total: 123 vs 57; proved hypoglycemic episodes 94 (76%) vs 21 (47%), chi(2) = 23.692, P < 0.01], The frequency of hypoglycemia before lunch was especially greater in premixed-insulin-treated subjects 64 (52%) vs 17 (30%), chi(2) = 7.762, P = 0.005. Several subjects from the premixed arm experienced too frequent hypoglycemic episodes to be recorded during 10AM-11AM almost every day. Subgroup analysis for patients treated with glargine: 28.2% (11 cases) of the patients in this group attained HbA1c 8.5% at 12 weeks, mean daily dosage for glargine were (0.66 +/- 0.30) U.kg(-1).d(-1). There were significant differences of baseline HbA1c, diabetes duration and baseline postprandial C-peptide between the two subgroups in glargine arm (HbA1c: 8.1% +/- 0.8% vs 9.6% +/- 1.2%; duration: 10 (6 - 14.5) years vs 13 (8 - 19.5) years; postprandial c peptide: 2.5 nmol/L (1.4 - 3.3) vs 1.4 (1.2 - 2.6) nmol/L, all P < 0.05).

CONCLUSION: Type 2 diabetic patients treated with twice-daily injection of premixed 30 R insulin with or without OAD (s) can be effectively and safely switched to basal insulin plus OAD. Pretreatment HbA1c, diabetes duration and postprandial C peptide are the key factors that closely related to efficacy of this new regimen.