Unexpected Inverse Relationship between Insulin Resistance and Serum Homocysteine in Healthy Subjects

H. ROSOLOVÁ, J. ŠIMON, O. MAYER Jr., J. RACEK¹, T. DIERZÉ, D. W. JACOBSEN²

Center of Preventive Cardiology, Second Department of Internal Diseases and ¹Institute of Biochemistry of the Medical Faculty Charles University, Plzeň, Czech Republic, ²Department of Cell Biology, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio, USA

Received January 10, 2001
Accepted March 28, 2001

Summary
Mild hyperhomocysteinemia has been established as a new independent risk factor for atherosclerosis and thrombosis. The metabolic syndrome of insulin resistance is associated with a high risk of coronary heart disease. Our objective was to determine if any relationship exists between the metabolic syndrome of insulin resistance in non-diabetic subjects and total serum homocysteine levels. Sixty-six healthy volunteers (33 males and 33 females) were selected from the population of Pilsen. Insulin resistance was measured by the Insulin Suppression Test using Octreotide. Steady-state plasma glucose concentrations at the end of the test period provided a quantitative measure of insulin resistance. Serum homocysteine level was estimated by high-pressure liquid chromatography. Serum folate and vitamin B12 were estimated using commercial kits on an Abbott IMx analyzer. All other laboratory tests were performed by standard methods in a routine biochemical laboratory. Subjects with the highest tertile of steady-state plasma glucose showed a significantly higher body mass index, blood pressure, fasting plasma triglyceride levels, plasminogen activator inhibitor-1 and lower HDL-cholesterol, i.e. an insulin resistance pattern. These subjects had significantly lower serum homocysteine levels compared with non-insulin resistant subjects. The negative association of insulin resistance and serum homocysteine was unexpected. The contribution of plasma folate levels to serum homocysteine levels and serum creatinine was significantly negative and positive, respectively.

Key words
Homocysteine · Insulin resistance · Coronary risk factors

Reprint requests
H. Rosolová, Center of Preventive Cardiology, Second Department of Internal Medicine, E. Beneše 13, 305 99 Plzeň, Czech Republic, e-mail : rosolova@fnplzen.cz