Long-term efficacy of insulin glargine after switching from NPH insulin as intensive replacement of basal insulin in Japanese diabetes mellitus. Comparison of efficacy between type 1 and type 2 diabetes (JUN-LAN Study 1.2).

To assess and compare the efficacy and safety of insulin glargine as intensive replacement of basal insulin in Japanese patients with type 1 (n = 72) and type 2 (n = 46) diabetes, we switched their intensive insulin regimen from NPH plus regular or rapid-acting insulin to glargine plus bolus insulin, which included regular and rapid-acting insulin, and recorded changes in glycemic control and frequency of hypoglycemia for 18 months. The dose titration of basal and bolus insulin was based on home self-monitored blood glucose measurements and monthly HbA(1C). Mean HbA(1C) level was improved significantly at 3 months after switching to glargine plus bolus insulin regimen and these effects continued for 18 months in both type 1 and type 2 diabetes patients (HbA(1C) level: type 1: baseline 8.9 +/- 2.6%, 18 months 7.8 +/- 1.5% (p<0.05), type 2: baseline 8.2 +/- 2.6%, 18 months 7.7 +/- 1.5%. Body weight was slightly but significantly increased at 18 months only in type 2 diabetes. Total daily bolus insulin doses were not changed but basal insulin could be increased significantly after switching regimens in both types diabetes compared with baseline. The frequency of mild to moderate hypoglycemia (self-assisted episodes, blood glucose <70 mg/dl) was marginally lower with glargine but not significantly. Self-monitored fasting blood glucose level was significantly improved after switching in type 2 diabetes. Patients with the worst HbA(1C) level at baseline exhibited more than 10% improvement in HbA(1C) level after switching both type 1 and type 2 diabetes. The HbA(1C) levels of the effectively treated patients were comparable to those of ineffectively treated ones at 6 months and the same improvement was seen at 18 months. Our results suggested that insulin glargine is more effective than NPH insulin as intensive replacement of basal insulin, particularly in those Japanese patients with difficult glycemic control with NPH insulin, equally in both type 1 and type 2 diabetes.