Fasting serum insulin levels and insulin resistance are associated with blood rheology in Japanese young adults without diabetes

OBJECTIVES To evaluate fasting serum insulin levels and insulin resistance, and their association with blood rheology, in Japanese young adults without diabetes. METHODS Blood samples were analysed and blood rheology was estimated using haematological parameters. Whole blood passage time was measured using a Hitachi MC-FAN(©) microchannel array flow analyser. RESULTS Out of 151 subjects (mean age, 24.1 ± 1.5 years), fasting serum insulin levels and insulin resistance (using homeostasis model assessment-estimated insulin resistance [HOMA-IR]), were positively correlated with longer whole blood passage times and higher values for haematocrit (Hct), haemoglobin (Hb), fibrinogen, body weight, body mass index (BMI), triglycerides, and low-density lipoprotein cholesterol (LDL-C)/high-density lipoprotein cholesterol (HDL-C) ratio, and were negatively correlated with HDL-C. Whole blood passage time correlated with body weight, BMI, LDL-C/HDL-C ratio, Hct, Hb, white blood cell (WBC) count, platelet count, fibrinogen, fasting serum insulin levels, and HOMA-IR. Multiple regression analysis revealed that whole blood passage time was independently associated with Hct, fibrinogen levels, and WBC count. CONCLUSIONS Fasting serum insulin levels and insulin resistance were associated with blood rheology, and may influence blood rheology by modulating haematological parameters and lipid parameters in young adults without diabetes.