One-year response to evening insulin therapy in non-insulin-dependent diabetes

Abstract

We studied the 1-year response and predictors of the response to combination therapy with evening insulin and oral agents in NIDDM patients with a secondary failure. Injection of intermediate-acting (Monotard HM) or long-acting (Ultratard HM) insulin was added to previous oral therapy in 17 diabetics (of mean age (+/- SD) 54 +/- 2 years, BMI 27.6 +/- 0.5 kg m-2). The initial insulin dose was in the range 10-16 U, and the mean dose was 23 +/- 2 U d-1 at 12 months. During the year, combination therapy reduced the mean fasting blood glucose concentration (12.7 +/- 0.6 vs. 8.4 +/- 0.7 mmol l-1, P less than 0.001) and HbA1 (10.7 +/- 0.3 vs. 9.8 +/- 0.4%, P less than 0.01). Body weight increased by 4.4 +/- 0.7 kg (P less than 0.001). The serum cholesterol concentration decreased by 14% (P less than 0.01), but serum triglyceride and HDL-cholesterol levels remained unchanged. Elevation of serum triglycerides and plasma free fatty acids (FFAs) at baseline predicted a poor long-term outcome to this mode of therapy. In conclusion, the addition of evening injections of insulin to oral therapy improves glycaemic control in poorly controlled NIDDM patients. However, initial hypertriglyceridaemia predicts a poor long-term outcome to evening insulin supplementation.