Background We have recently reported that men with a persistently elevated plasma B-type natriuretic peptide (BNP) level show accumulation of metabolic syndrome-related factors, but women do not show this tendency and the cause for a gender difference is unknown. We examined the effect of high molecular weight (HMW) adiponectin as a biomarker closely associated with the metabolic syndrome on this difference.
Methods Subjects who performed medical check-ups in 2005 and 2006 were enrolled. The 1681 (1061male,620 female, mean age 51.4 years) Japanese subjects without established heart disease were analyzed. The subjects were divided by sex and BNP level (higher BNP group, ≥40 pg/ml; lower BNP group, ≥40pg/ml for two consecutive years), and plasma HMW adiponectin level in the different groups were examined using an enzyme-linked immunosorbent assay (ELISA) kit.
Results Metabolic syndrome-related factors accumulated in males with higher BNP, but not in females with higher BNP. HMW adiponectin was higher in females with higher BNP (9.8 μg/ml vs. 6.1μg/ml in lower BNP group, p<0.01), but this difference was not observed in males (3.7 μg/ml vs.2.8 μg/ml, p=0.37). However, a positive correlation was confirmed between BNP and HMW adiponectin levels in both genders. HMW adiponectin level showed a positive (HDL cholesterol) or a negative (TG) correlation in both genders, and showed a negative correlation with glucose level only in females. Conclusion Our findings suggest that higher BNP level with relatively lower HMW adiponectin level may be associated with accumulation of metabolic syndrome-related factors in men.

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Background The relationship between serum amyloid A (SAA) as an inflammation marker and interleukin-6 (IL-6) as a factor inducing SAA provides an important insight into vascular lesions in a population of diabetic patients.
Methods We investigated the use of piecewise linear regression as a replacement for the simple correlation diagram method in order to uncover the pathologic condition hidden behind their correlation.
Results and Conclusions Significant associations were found between SAA and IL-6 (r=0.469) and between ferritin (Ft) and lipoprotein lipase (LPL) mass (r=0.314). We attempted to detect pathologic tendencies related to SAA in the abnormal range using the piecewise linear regression method, and confirmed the close relationship between SAA and IL-6 related to the mechanism for cytokine induction. In addition, our analyses characterized how the inflammation marker SAA was related to LPL mass as a marker of endothelial cell damage and Ft as an oxidative stress marker protein with antioxidant properties.

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Background and Methods To clarify the factors which influence B-type natriuretic peptide (BNP) concentration in healthy individuals,559 individuals (267 men and 292 women) were examined for their BNP levels and other indices.
Results The BNP concentrations were significantly higher in female than male counterparts and increased with increasing age. The maximum difference of mean BNP concentration was observed in females in their 60s and males in their 30s (25.2 mg/dl,7.1 mg/dl respectively), the difference was more than 3.5times. Positive relations were observed in age, systolic BP, pulse pressure and augmentation index (Al); negative relations were observed in immunoreactive insulin (IRI), γ-GTP, albumin, Hb, hematocrit, RBC, uric acid and heart rate. The most significant correlation with serum BNP level was observed in Hb (r=0.329). There was a statistical significance in mean overall serum BNP level between the obesity and normal weight groups (p=0.009). The difference of mean BNP concentration between smoker and nonsmoker groups was not statistically significant but smokers tended to have lower BNP concentrations than nonsmokers.
Conclusion These differences were considered to be caused by the subsequent secondary erythrocytosis in obesity and smoking. Further studies of BNP change in various situations are needed to clarify the mechanism inducing cardiac stress.

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Background HbA1c is proposed as an optional component of metabolic syndrome (MS).
Therefore, we studied an optimal cut point of HbA1c as a component of MS. Methods Medical check-up data of 1354 men and 814 women were examined using Spearman's correlation coefficients among MS-related components, stepwise logistic regressions using MS and Japanese MS (JMS) as dependent variables, and receiver operating characteristic (ROC) curves for diagnosing MS and JMS. MS was defined by revised National Cholesterol Education Program (NCEP) criteria for Japanese and JMS was defined by the Examination Committee for Criteria of Metabolic Syndrome. The optimal cut point was defined as the point on the ROC curve from where the distance to the point where both sensitivity and specificity were one was minimal.
Results The correlation coefficients of HbA_1c with other MS-related components and the area under ROC curve (AUC) of HbA1c for diagnosing MS and JMS were comparable to those of other MS-related cornponents. HbA1c was an independent marker for JMS, but not for MS. AUC of HbA1c for diagnosing MS and JMS were 0.731 and 0.717 in men and 0.737 and 0.802 in women, respectively. The optimal cut point with its sensitivity and specificity of HbA_1c for diagnosing MS and JMS were 5.15% with 0.61 and 0.75 and 5.2% with 0.57 and 0.79, respectively in men and 5.2% with 0.56 and 0.77 and 5.2% with 0.68 and 0.75, respectively in women. Conclusion We recommend 5.2% as an optimal cut point of HbA_1c for diagnosing MS among Japanese.

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Background Waist circumference (WC) is important as an indicator for obesity and used as diagnostic criteria for metabolic syndrome in Japan. To investigate the difference by the criteria of WC, we compared the relation of WC to cardiac performance in subjects of health screenings.
Methods WC, BMI, blood samples. UCG and BP were measured in 445 men without cardiovascular disease who underwent one night two day health screenings (Ningen Dock). By their WC and BMI, WC85obesity (WC≥85 cm for obesity), WC90 obesity (WC≥90 cm for obesity) and BMI obesity (BMI≥25 for obesity) were defined. After comparing cardiac volume, function and BP between obesity and non-obesity groups, correlation of each parameter to WC and BMI were investigated.
Results Aortic diameter, left atrial dimension (LAD), left ventricular wall thickness, and BP were significantly increased in WC85 obesity. Left ventricular volume and stroke volume were also increased in WC90 obesity. These parameters correlated well with WC, and in multivariable analysis, LAD and posterior wall thickness were the independent predictor for WC. BMI obesity revealed almost same results with WC90 obesity, and LAD and diastolic BP predicted BMI independently.
Conclusions Cardiac volume is increased and hypertrophied in obese men undergoing health screenings. Criteria for obesity changed the relation of cardiac parameters to WC and BMI. WC85 obesity revealed obesity related early cardiac changes and WC90 revealed advanced cardiac changes, almost same with BMI obesity. (Ningen Dock 2009; 23: 29-35)

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