[Obesity and dyslipidemia. Nature of an association]

Obesity is commonly associated with hyperlipidemia on the basis of clinical and epidemiological studies, but the mechanisms of that relationship are not well understood. To evaluate the contribution of obesity to fasting levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG), we retrospectively analyzed data of 209 patients (175 women and 34 men) attending our outpatient clinic to lose weight. Hyperlipidemia, namely hypertriglyceridemia and low levels of HDL-C, was more frequent in more advanced grades of obesity. Fifty per cent of men with moderate obesity were found to have hypertriglyceridemia and 41.6% showed low levels of HDL-C. However, the relationship between obesity and hyperlipidemia is confounded by age and is not significant when body mass index (BMI) is correct for age. After this correction, we only found a significant correlation (r = 0.93, p = 0.01) between BMI and hypertriglyceridemia in female patients. We conclude that hyperlipidemia and obesity are associate but their relationship is weak and influenced by age. Also important in this relationship seems to be the distribution of body fat.