OBJECTIVETo explore the optimal cut-off values of waist-to-height ratio (WHtR) for detecting the severe central obesity and low body weight in adult Chinese population.

METHODSA total of 30 630 participants aged 35-59 years from different areas in mainland China were surveyed for cardiovascular diseases risk factors in two independent cross-sectional studies that carried out in 1992-1994 and 1998, respectively. Indices, such as sensitivity, specificity for hypertension, abnormal glucose, high serum total cholesterol, low serum high density lipoprotein cholesterol and clustering of risk factors (number ≥ 2) were calculated to evaluate the efficacy individual cut-off point of WHtR. The cut-off point value for obvious central obesity was fixed on the point whose specificity of the point was gathered more than 90%. And the cut-off point value to indicate low weight was determined by the percentile distribution of WHtR, at which the 5th percentile of point, both in male and female population. Based on the principle of convenient and practical for use, the optimal cut-off point values of WHtR for low weight and obvious central obesity were determined.

RESULTSThe cut-off values of WHtR to detect severe central obesity were 0.54 and 0.57 for men and women, respectively. Additionally, the cut-off points of WHtR for each of the 4 cardiovascular risk factors to evaluate the severity separately ranged from 0.54 to 0.55 in male, and ranged from 0.57 to 0.58 in female. The 5th percentile of WHtR, which was the point value of WHtR to indicate low body weight, was 0.40 in both male and female population.

CONCLUSIONOur data suggest that the optimal cut-off value of WHtR for defining severe central obesity and low body weight should be 0.57 and 0.40, respectively.