Homocysteine plasma levels are independently associated with insulin resistance in normal weight, overweight and obese pre-menopausal women

Objectives: The aim of the present study was to examine the relationship of homocysteine (Hey) plasma levels to insulin resistance (IR). Design: A cross-sectional study in a primary care setting. Subjects and Methods: Fasting Hey levels were measured in the plasma of 44 pre-menopausal women [17 normal weight (body mass index BMI 20.0-24.9 kg/m(2)), 7 overweight (BMI 25.0-29.9 kg/m(2)), 20 obese (BMI greater than or equal to 30.0 kg/m(2))], aged 18-45 yr. Other measurements included: central fat accumulation, as evaluated by waist circumference; IR, as calculated by homeostatic model assessment (HOMA(IR)); systolic and diastolic blood pressure; and fasting concentrations of glucose, insulin and lipids (total cholesterol, HDL-cholesterol, triglycerides). Results: Hey was positively correlated with insulin concentrations (p <0.01), HOMA(IR) (p <0.01), and systolic and diastolic blood pressure (p <0.01 and p <0.05, respectively). After multivariate analysis, only HOMAIR maintained an independent association with Hey (p <0.05), irrespective of age and other anthropometric and biochemical variables. Lastly, we observed a gradual increase in Hey plasma levels across the age- and BMI-matched quartiles in which the whole population was divided according to HOMA(IR) levels (F: 2.73,p <0.05 for linear trend). Conclusions: Our study shows that Hey plasma levels are independently associated with IR in apparently healthy normal weight, overweight and obese pre-menopausal women, thus suggesting a possible role of IR and/or hyperinsulinaemia in increasing Hcy plasma levels. Since Hcy is a well-known cardiovascular risk factor, higher Hey plasma levels may well be a further mechanism explaining the higher risk of coronary heart disease in patients affected by IR. (C) 2001, Editrice Kurtis.