Morning or bedtime NPH insulin combined with sulfonylurea in treatment of NIDDM.

OBJECTIVE: To compare the effect of morning and bedtime NPH insulin combined with daytime sulfonylurea on glycemic control in non-insulin-dependent diabetes mellitus (NIDDM) patients no longer responding to treatment with sulfonylureas alone. RESEARCH DESIGN AND METHODS: Twenty-four NIDDM patients who fulfilled these criteria were randomized to treatment with Protaphan human insulin in the morning or at bedtime (22 +/- 1 IU) plus 3.5 mg glibenclamide twice a day. RESULTS: Morning and bedtime NPH insulin resulted in equal reduction of HbA1 (from 13.5 +/- 0.3 to 9.4 +/- 0.1 and 9.6 +/- 0.2%, respectively) and mean self-monitored blood glucose (9.2 +/- 0.5 vs. 10.1 +/- 0.4 mM). Bedtime insulin resulted in lower morning blood glucose (7.8 +/- 0.5 vs. 9.1 +/- 0.4 mM; P less than 0.01), whereas morning insulin resulted in lower evening blood glucose (10.1 +/- 0.6 vs 12.1 +/- 0.6 mM, P less than 0.01). CONCLUSIONS: Morning and bedtime NPH insulin combined with glibenclamide are equipotent in the treatment of NIDDM patients with secondary failure to sulfonylurea. However, this treatment regimen normalizes blood glucose only in a small group of patients. Therefore, more intensified insulin therapy seems to be required to achieve this goal.