Insulin glargine or NPH combined with metformin in type 2 diabetes: the LANMET study.

AIMS/HYPOTHESIS: In type 2 diabetic patients we compared 9 months of combination therapy with insulin glargine and metformin with 9 months of NPH insulin combined with metformin. The primary focus was changes in HbA(1c); secondary focus was diurnal glucose profiles and symptomatic hypoglycaemia. METHODS: In this investigator-initiated open, parallel-group clinical trial involving seven centres, 110 insulin-naive type 2 diabetic patients with poor glycaemic control (HbA(1c) >or=8.0%) on oral hypoglycaemic agents (90% using sulfonylurea plus metformin) were randomised to receive bedtime insulin glargine with metformin (G+MET) or bedtime NPH with metformin (NPH+MET) for 36 weeks. The patients were taught how to self-adjust their insulin dose and use a modem to send the results of home glucose monitoring to treatment centres. The goal was to achieve a fasting plasma glucose (FPG) of 4.0 to 5.5 mmol/l in both groups. RESULTS: During the last 12 weeks, FPGs averaged 5.75+/-0.02 and 5.96+/-0.03 mmol/l (p<0.001) and insulin doses were 68+/-5 and 70+/-6 IU/day (0.69+/-0.05 and 0.66+/-0.04 IU kg(-1) day(-1), NS) in the G+MET and NPH+MET groups, respectively. At 36 weeks, mean HbA(1c) was 7.14+/-0.12 and 7.16+/-0.14%, respectively (NS). Symptomatic, but not confirmed symptomatic, hypoglycaemia was significantly lower during the first 12 weeks in the G+MET group (4.1+/-0.8 episodes/patient-year) than in the NPH+MET group (9.0+/-2.3 episodes/patient-year, p<0.05), but not significantly different thereafter. Glucose levels before dinner were higher in the NPH+MET group (10.1+/-0.3 mmol/l) than in the G+MET group (8.6+/-0.3 mmol/l, p=0.002) throughout the 36-week study. With regard to baseline characteristics such as initial glycaemia or C-peptide, there was no difference between patients who achieved good glycaemic control (HbA(1c) <7.0%) and those who did not. Differences were seen in the following: between study centres, weight gain during the run-in period and insulin therapy, and FPG during the last 12 weeks (5.7+/-0.2 vs 6.7+/-0.3 mmol/l for patients reaching vs those not reaching target, p<0.01). CONCLUSIONS/INTERPRETATION: Good glycaemic control can be achieved with both G+MET and NPH+MET. Use of G+MET reduces symptomatic hypoglycaemia during the first 12 weeks and dinner time hyperglycaemia compared with NPH+MET.

Comparison of bedtime insulin regimens in patients with type 2 diabetes mellitus. A randomized, controlled trial.

BACKGROUND: Compared with other insulin regimens, combination therapy with oral hypoglycemic agents and bedtime insulin produces similar improvement in glycemic control but induces less weight gain. OBJECTIVE: To determine whether bedtime insulin regimens differ with respect to their effects on weight gain in patients with type 2 diabetes. DESIGN: Randomized, controlled trial. SETTING: Four outpatient clinics at central hospitals. PATIENTS: 96 patients (mean age, 58 +/- 1 years; mean body mass index, 29 +/- 1 kg/m2) whose type 2 diabetes was poorly controlled with sulfonylurea therapy (mean glycosylated hemoglobin value, 9.9% +/- 0.2%; mean fasting plasma glucose level, 11.9 +/- 0.3 mmol/L [214 +/- 5 mg/dL]). INTERVENTION: Random assignment to 1 year of treatment with bedtime intermediate-acting insulin plus glyburide (10.5 mg) and placebo, metformin (2 g) and placebo, glyburide and metformin, or a second injection of intermediate-acting insulin in the morning. Patients were taught to adjust the bedtime insulin dose on the basis of fasting glucose measurements. MEASUREMENTS: Body weight, biochemical and symptomatic hypoglycemias, and indices of glycemic control. RESULTS: At 1 year, body weight remained unchanged in patients receiving bedtime insulin plus metformin (mean change, 0.9 +/- 1.2 kg; P < 0.001 compared with all other groups) but increased by 3.9 +/- 0.7 kg, 3.6 +/- 1.2 kg, and 4.6 +/- 1.0 kg in patients receiving bedtime insulin plus glyburide, those receiving bedtime insulin plus both oral drugs, and those receiving bedtime and morning insulin, respectively. The greatest decrease in the glycosylated hemoglobin value was observed in the bedtime insulin and metformin group (from 9.7% +/- 0.4% to 7.2% +/- 0.2% [difference, -2.5 +/- 0.4 percentage points] at 1 year; P < 0.001 compared with 0 months and P < 0.05 compared with other groups). This group also had significantly fewer symptomatic and biochemical cases of hypoglycemia (P < 0.05) than the other groups. CONCLUSIONS: Combination therapy with bedtime insulin plus metformin prevents weight gain. This regimen also seems superior to other bedtime insulin regimens with respect to improvement in glycemic control and frequency of hypoglycemia.

Effect of obesity on the response to insulin therapy in noninsulin-dependent diabetes mellitus.

An initial improvement in glycemic control is often followed by gradual deterioration of glycemia during insulin treatment of patients with noninsulin-dependent diabetes mellitus (NIDDM). We examined the causes of such worsening in a 12-month follow-up analysis of 100 insulin-treated NIDDM patients in the Finnish Multicenter Insulin Therapy Study who were treated with either combination therapy with insulin or insulin alone. In the entire study group, glycemic control averaged 9.7 +/- 0.2% at 0 months and 8.0 +/- 0.1%, 8.0 +/- 0.1%, 8.2 +/- 0.1%, and 8.5 +/- 0.2% at 3, 6, 9, and 12 months (P < 0.001 for each time point vs. 0 months). Glycemic control at 12 months was significantly worse than that at 3 (P < 0.001), 6 (P < 0.001), and 9 months (P < 0.02). Baseline body mass index was the most significant predictor of deterioration in glycemic control. During 1 yr, hemoglobin A1c decreased almost 3-fold more (by 1.7 +/- 0.2%; P < 0.001 vs. 0 months) in patients whose baseline weight was below the mean baseline body mass index of 28.1 kg/m2 (nonobese patients) than in those whose weight exceeded 28.1 kg/m2 (obese patients; 0.5 +/- 0.2%; P = NS vs. 0 months; P < 0.01 vs. obese patients). Glycemic control improved similarly over 1 yr in the nonobese subjects and deteriorated similarly in the obese patients regardless of their treatment regimen. Insulin doses, per body weight, were similar in the nonobese and obese patients. The nonobese patients consistently gained less weight during 12 months of combination therapy with insulin (3.5 +/- 0.6 kg at 12 months) than during insulin therapy alone (5.1 +/- 0.6 kg; P < 0.05). The treatment regimen did not influence weight gain in the obese group, who gained 4.4 +/- 1.0 kg during combination therapy with insulin and 4.5 +/- 1.1 kg during insulin therapy alone. We reached the following conclusions: 1) after an initial good response, glycemic control deteriorates more in obese than in nonobese patients with NIDDM; 2) in obese patients, weight gain per se cannot explain the poor glycemic response to combination or insulin therapy, but it may induce a disproportionately large increase in insulin requirements because of greater insulin resistance in the obese than in the nonobese; 3) in nonobese patients, glycemic control improves equally during 1 yr with combination therapy with insulin and insulin alone, but combination therapy with insulin is associated with less weight gain than treatment with insulin alone; 4) weight gain appears harmful, as it is associated with increases in blood pressure and low density lipoprotein cholesterol.