Objective: Obesity promotes the development of diseases in many organ systems. The relationship between lipoporotein (a), lipid parameters and insulin resistance which accompany obesity has not been clarified. The correction of dyslipidemia in obesity and insulin resistance is of critical importance for prevention of coronary heart disease. The aim of this study is to determine the relationship between the body mass index and serum levels of lipids and lipoprotein (a), and to clarify the interaction with insulin resistance.

Materials and Methods: In this study, control group consisted of 35 adults, 19-82 years of age, and body mass index 24.9³ - ³18.5. Obese and overweight group consisted of 70 adults, 20-82 years of age, and body mass index >24.9. Serum levels of lipoprotein (a), apolipoprotein A1 and apolipoprotein B were measured by nephelometric method, triglyceride, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, glucose were measured by photometric methods and insulin was measured by an immunoassay method. The body mass index was calculated as kg/m² and the insulin resistance was calculated as (HOMA-IR) = [fasting insulin (µU/mL) X fasting blood glucose (mmol/L)] / 22.5.

Results: Serum triglyceride and apolipoprotein B levels were significantly higher and levels of high density lipoprotein cholesterol, apolipoprotein A1 were significantly lower in obese and overweight group compared to controls while Lp(a) levels showed no significant difference. It has been observed that the levels of lipoprotein (a), apolipoprotein B and triglyceride were significantly higher while high density lipoprotein cholesterol was significantly lower in obese adult with insulin resistance compared with controls (p<0.05).

Conclusion: Our results suggest that the levels of lipoprotein (a) might be an important risk factor in obese and overweight population with insulin resistance.