The cut-off point of waist circumference for identifying metabolic syndrome in people over 30 years of age in Shanghai Fengcheng community

Objective To investigate the appropriate cut-off point of waist circumference as a component of metabolic syndrome(MS) for residents over 30 years of age in Shanghai rural communities. Methods A cross sectional survey with random sampling was performed including 1 041 residents over 30 years of age in Fengcheng community. It was used to investigate the correlation between waist circumstance and clustering of other MS components, and to find out the appropriate cut-off point of waist circumference with low false positive and low false negative rates for identifying two or more risk components of MS. Results The odds ratio (OR) of clustering of risk components increased significantly with the increase in size of waist circumference. Waist circumference ≥85.0 cm for men and ≥80.0 cm for women corresponded to the shortest distance in receiver operating characteristics (ROC) curve. The prevalence of MS was 15.32% in men with waist circumference ≥85.0 cm and 12.35% in women with waist circumference ≥80.0 cm respectively. In these patients, the combination of increased waist circumference,high blood pressure and high blood glucose was the most frequent. Conclusions MS could be defined if a person in Shanghai rural community had three or more of the following five components: waist circumference ≥85.0 cm in men or ≥80.0 cm in women; systolic blood pressure ≥130 mm Hg (1 mm Hg = 0.133 kPa) or diastolic blood pressure ≥85.0 mm Hg; blood triglyeride≥1.70 mmol/L; high density lipoprotein cholesterol1.03 mmol/L in men or 1.29 mmol/L in women; fasting blood glucose ≥5.6 mmol/L.