Optimal cut-off points for waist circumference in the definition of metabolic syndrome: a cross-sectional study in rural Bangladesh.

Abstract

Objective: To determine optimal waist circumference (WC) cut-off points for identifying metabolic syndrome (MetS) in Bangladeshi adults, with the aim of enhancing diagnostic accuracy specific to this population.

Design: Cross-sectional analysis.

Setting: Rural community in Chandra, Bangladesh.

Participants: A total of 2293 adults aged 20 years and older.

Primary and secondary outcome measures: MetS was defined using the modified National Cholesterol Education Program Adult Treatment Panel III criteria. Receiver operating characteristic (ROC) curves and Youden's Index were used to identify WC cut-off points that maximised sensitivity and specificity for diagnosing MetS. Restricted cubic spline regression was employed to explore the non-linear relationship between WC and MetS risk.

Results: The optimal WC cut-off points for predicting MetS were 90 cm for men (sensitivity 55.2%, specificity 94.3%, OR 12.5, 95% CI 8.6 to 18.0) and 80 cm for women (sensitivity 86.7%, specificity 71.9%, OR 15.6, 95% CI 11.4 to 21.3). The area under the ROC curve was 0.819 for men and 0.827 for women. Non-linear analysis indicated a significant increase in MetS risk beyond these thresholds, with a steeper risk gradient observed in men.

Conclusions: This study establishes WC cut-off points of 90 cm for men and 80 cm for women as optimal for diagnosing MetS in Bangladeshi adults, underscoring the necessity of population-specific diagnostic criteria to improve early detection and management.