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Background: A precise knowledge of the prevalence and importance of cardiovascular risk factors will facilitate the development of preventive strategies. Aim: To study cardiovascular risk factors among healthy young adults. Subjects and methods: Eight hundred and fifty subjects aged 22 to 28 years, living in two cities in Valparaiso province, were studied. Weight, height and blood pressure were recorded. A fasting blood sample was obtained from 806 individuals (54% female), to measure plasma lipids, glucose and insulin levels, to estimate their homeostasis model assessment scores (HOMA) and to evaluate the occurrence of metabolic syndrome. Results: Five percent of the studied population had high blood pressure, 14% had obesity, 57% smoked, 25% had high total cholesterol levels, 10.5% had high levels of low density lipoprotein cholesterol, 46% had low levels of high density lipoprotein cholesterol, 16% had high triglyceride levels, 36% had insulin resistance, 7% had a metabolic syndrome, 14% were heavy drinkers and 38% were sedentary. Women had a higher prevalence of obesity and metabolic syndrome. In only 24% of the studied subjects, no risk factor was identified. Conclusions: A high prevalence of cardiovascular risk factors was found in this population of young adults (Rev Méd Chile 2003; 131: 973-80).

Cholesterol has evolved to fulfill sophisticated biophysical, cell signalling, and endocrine functions in animal systems. At the cellular level, cholesterol is found in membranes where it increases both bilayer stiffness and impermeability to water and ions. Furthermore, cholesterol is integrated into specialized lipid-protein membrane microdomains with critical topographical and signalling functions. At the organismal level, cholesterol is the precursor of all steroid hormones, including gluco- and mineralo-corticoids, sex hormones, and vitamin D, which regulate carbohydrate, sodium, reproductive, and bone homeostasis, respectively. This sterol is also the immediate precursor of bile acids, which are important for intestinal absorption of dietary lipids as well as energy homeostasis and glucose regulation. Complex mechanisms maintain cholesterol within physiological ranges and the dysregulation of these mechanisms results in embryonic or adult diseases, caused by either excessive or reduced tissue cholesterol levels. The causative role of cholesterol in these conditions has been demonstrated by genetic and pharmacological manipulations in animal models of human disease that are discussed herein. Importantly, the understanding of basic aspects of cholesterol biology has led to the development of high-impact pharmaceutical therapies during the past century. The continuing effort to offer successful treatments for prevalent cholesterol-related diseases, such as atherosclerosis and neurodegenerative disorders, warrants further interdisciplinary research in the coming decades.

Background/ObjectivesAbdominal obesity (AO) is associated with elevated risk for cardiovascular diseases; however, this association is less clear for non-obese people. We estimated the association of AO and cardiovascular risk factors (CVRF) and disease in non-obese adult individuals from Chile.Subjects/Methods5248 adults (15 years of age or older) of both sexes from the Chilean National Health Survey (October 2009 –September 2010, response rate 85%.) were included. Information on myocardial infarction and stroke was self-reported. BMI, waist circumference (WC), arterial pressure, plasma glucose, and cholesterol levels were measured. Predictive accuracy of WC was evaluated by area under curve of receiver operating characteristic analysis and cut off points were established by Youden Index. Relationship between AO and CVRF was analyzed by Chi-squared tests.ResultsNormal weight/overweight/obesity were present in 34.4%/45.2%/18.1% of men and 33.4%/33.6%/27.5% of women. Predictive accuracy of WC to identify at least one CVRF was 0.70/0.67 and optimal cutoff points for WC in non-obese subjects were 91/83 cm in men/women, respectively. AO was present in 98.2%/99.1% of obese, 70.5%/77.4% of overweight and 12.4%/16.4% of normal weight men/women. AO was associated with increased frequency of CVRF in overweight men (6/8 and stroke) and women (4/8) and higher frequency in normal weight men (8/8 and myocardial infarction/stroke) and women (6/8 and myocardial infarction).ConclusionsWC cutoff points calculated for non-obese chilean population discriminate more differences in CVRF in normal weight woman. AO significantly increases the frequency of CVRF and diseases in overweight and especially normal weight individuals. WC can be used as a low cost, feasible and reproducible predictor for CVRF in non-obese individuals in most clinical settings.