OBJECTIVE:To assess the relative importance of the extent and regional distribution of fat for metabolic risk factors in young adults. DESIGN: Cross-sectional study of findings from a hospital-based case-control study. SUBJECTS: A total of 46 adult Danish Caucasian patients (40 men and six women, aged 34-54 y). Of these, 22 had had non fatal acute myocardial infarction before 41 y of age and 24 were age-and gender-matched controls without coronary heart disease. MEASUREMENTS: Four measurements of fat: body mass index (BMI, kg/m 2 ), body fat percentage measured using a dual energy X-ray absorptiometry (DEXA) scanner, waist/hip circumference ratio (WHR), and intra-abdominal adipose tissue area measured using computed tomography (CT) scanning, and eight metabolic risk factors: systolic and diastolic blood pressure, HbA 1c percentage, fasting concentrations of capillary whole blood glucose, high-density lipoprotein (HDL) cholesterol, serum triglyceride, plasma plasminogen activator inhibitor 1 (PAI-1), and urinary albumin:creatinine excretion ratio. RESULTS: Of 46 participants, 10 were obese (BMI 430 kg/m 2 ), 12 were abdominally obese (WHR 40.90 for men and 40.85 for women), and 20 were intra-abdominally obese (intra-abdominal adipose tissue area 4135 cm 2 ). Men had a higher intraabdominal adipose tissue area than women (P ¼ 0.0053, Mann-Whitney U-test). In multiple regression analyses of the four fat variables, only intra-abdominal adipose tissue area significantly predicted the levels of six metabolic risk factors: systolic blood pressure, diastolic blood pressure, fasting concentrations of capillary whole blood glucose, serum HDL cholesterol, serum triglyceride, and PAI-1. The intra-abdominal adipose tissue area had a linear relation with the six metabolic risk factors. CONCLUSIONS: For young individuals, intra-abdominal fat is the important component of the body fat for six of the eight metabolic risk factors. Intra-abdominal fat might contribute to that most patients with acute myocardial infarction at a young age are men. Overall, obesity is an excess of total body fat and may be diagnosed as a high BMI (Z30 kg/m 2 ). However, a dual energy X-ray absorptiometry (DEXA) scanner measures the body fat mass more precisely as a percentage of the weight of the body.5 Abdominal obesity may be diagnosed as a high waist/hip circumference ratio (WHR) that can be because of an excess of either subcutaneous or intra-abdominal fat. A computed tomography (CT) scanning gives a more precise measure of the extent of the abdominal fat, and allows separate measurements of the subcutaneous and intraabdominal adipose tissue. 5 Furthermore, World HealthOrganization (WHO) developed criteria for a metabolic syndrome including insulin resistance, overall obesity measured as BMI or abdominal obesity measured as WHR, and raised the levels of at least three of five metabolic risk factors. 6There is no consensus as to the importance of the different measurements of body fat.7 Therefore, we explored the relation between extent and region...

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Background Of major coronary risk factors, smoking and total cholesterol were significant in a previous Danish casecontrol study of myocardial infarction at a young age.Objective To determine whether smoking was an important coronary risk factor in the context of new and major anthropometric and biochemical risk factors for myocardial infarction in individuals less than 41 years of age.Methods A prevalence hospital-based matched casecontrol study of young individuals. We selected 22 Caucasian cases and 24 Caucasian controls without coronary heart disease matching for age and gender and studied a series of major coronary risk factors and newer anthropometric and biochemical variables. ResultsIn conditional univariate logistic regression analyses, the following factors were significantly associated with the coronary risk: family history, social class, smoking, intraabdominal adipose tissue area as percentage of total abdominal adipose tissue area on a CT scan, glycosylated haemoglobin level, systolic blood pressure, total cholesterol, low density lipoprotein (LDL) cholesterol, homocysteine, and fibrinogen levels (P o 0.05). However, in multiple conditional logistic regression analyses, only smoking, LDL cholesterol, and fibrinogen levels remained significant. Ten cases (46%) and none of the 24 controls were smokers with a LDL cholesterol level 4.5 mmol/l and a fibrinogen level 3.7 g/l (P ¼ 0.0003, Fisher's exact test). ConclusionOut of a series of major and newer coronary risk factors in young Western Caucasians, smoking, and levels of LDL cholesterol, and fibrinogen were independent significant coronary risk factors. The findings need to be validated in prospective studies.

Because only some coronary risk factors have been evaluated for an association with plasma plasminogen activator inhibitor 1 (PAI-1) activity, this cross-sectional study examined the association between 27 coronary risk factors and PAI-1 in 24 healthy persons without coronary heart disease (control persons) and 22 patients who had survived myocardial infarction (cases). The coronary risk factors included major coronary risk factors such as age, anthropometric measures such as intraabdominal fat, and biochemical analytes such as serum concentration of triglyceride and plasma von Willebrand factor activity. The associations were analyzed in univariate and multiple linear regression analyses. For the control persons, triglyceride and von Willebrand factor were significantly associated with PAI-1 activity (p=0.0002, R2=0.55). In contrast for the 24 cases, age and intraabdominal adipose tissue were significantly associated with PAI-1 (p=0.0011, R2=0.51). Coronary risk factors explained more than half the variation of PAI-1 activity for both study groups. However, healthy persons and patients with previous myocardial infarction differed regarding coronary risk factors associated with PAI-1.

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