Metabolic syndrome in Japanese diagnosed with visceral fat measurement by computed tomography

Abstract
The metabolic syndrome represents an aggregation of cardiovascular risk factors including obesity, raised blood pressure, impaired glucose tolerance, and dyslipidemia that are associated with increased incidence of arteriosclerosis. Evidence accumulated indicates that the visceral fat accumulation is essential in the development of the syndrome. To investigate the prevalence of the metabolic syndrome in Japan, we analyzed cross-sectional data from 3574 middle aged Japanese (2947 men and 627 women, aged 40-59 years) in a large company, whose visceral fat accumulation was assessed by computed tomography. We employed receiver operation characteristic analysis to identify the optimal visceral fat area (VFA) value that has the sensitivity and the specificity to predict the presence of at least two components of the syndrome in an individual. The sensitivities and the specificities for men were 0.67 and 0.60 at VFA of 100 cm2, and for women, 0.73 and 0.70 at VFA of 65 cm2, respectively. Waist circumferences that corresponded to the VFA cutoff were 86.0 cm for men, and 77.0 cm for women. Using 100 cm2 in men and 65 cm2 in women as the criteria of visceral adiposity, the prevalence of the metabolic syndrome was 25.5% in men and 11.0% in women. Although obesity is less prevalent than in western countries, the metabolic syndrome is substantially widespread in Japan. (Communicated by Hiroo IMURA, M.J.A.)