Purpose: The risk of metabolic syndrome (MetS) is assessed based on the presence of risk factors that include dyslipidemia, hyperglycemia, hypertension and obesity. In this study, we assessed the risk of MetS using principle component (PC) analysis of MetS diagnostic parameters and examined whether the resulting eigenvalues are associated with the circulating concentrations of inflammatory cytokines [interleukin (IL)-1β and IL-6] and a marker for insulin sensitivity (adiponectin) in middle-aged Japanese men without treatment for metabolic diseases.
Materials: We conducted a cross-sectional study of 308 Japanese men without treatment for metabolic diseases aged 40-69 years who participated in health checkups in Japan. We calculated the PC1 score from the following MetS diagnostic parameters: body mass index (BMI), fasting blood glucose, diastolic blood pressure, triacylglycerol and high-density lipoprotein cholesterol. We compared the relationship between PC1 scores and other clinical parameters, including IL-1β, IL-6 and adiponectin, by Spearman's rank correlation coefficient analyses and Jonckheere-Terpstra test.
Results: The associations for most clinical parameters were higher with the PC1 score than with other MetS diagnostic parameters. Homeostasis model assessment-insulin resistance, an index of insulin resistance, showed stronger associations with PC1 score than with MetS diagnostic parameters. Significant associations for IL-1β, IL-6 and adiponectin were observed with the PC1 score, BMI and triacylglycerol; these associations were higher with the PC1 score than with BMI and triacylglycerol.
Conclusions: The present results show that the PC1 score is closely associated with parameters of MetS, inflammation and insulin resistance.