Long-term effect of intensified insulin treatment on lipid parameters in diabetes mellitus type I

Premature atherosclerosis is often found in patients with diabetes mellitus (DM) type I, and alterations in lipid metabolism seem to play an important role in the development of this complication. Intensified insulin therapy improves glycemic control parameters significantly. To evaluate the effect of this optimized insulin treatment (OIT) not only on glycemic control, but also on plasma lipids, 24 patients with DM type I (19 men and 5 women, 18 to 61 years) were switched from a standard insulin therapy to a regimen of OIT which has been maintained for more than 3 years now. After 2 years on OIT a reduction of HbA1c values from 8.1% to 7.5% (p less than 0.01) was accompanied by an increase in HDL cholesterol from 52 to 67 mg/dl (p less than 0.05) and a decrease of triglyceride levels from 319 to 67 mg/dl (p less than 0.001). At the end of the second year on OIT some of the patients exhibited a reversal of the favorable trend in HbA1c and lipid values. Intensified instructions regarding the implementation of OIT were therefore repeated and resulted in a renewed improvement of overall HbA1c, HDL cholesterol and triglyceride levels to 6.43%, 67 mg/dl, and 78 mg/dl, respectively. Our findings underline the value of OIT not only for glycemic control, but also for the control of plasma lipids considered to be major risk factors for coronary artery disease.