Waist circumference cutoff points in school-aged Chinese Han and Uygur children.
OBJECTIVE
To examine the distribution of age- and gender-specific waist circumference (WC) and to identify optimal cutoffs for predicting cardiovascular (CV) risk factors in Chinese Han and Uygur children.


METHODS
In total 4,224 Han and Uygur children aged 7-18 were randomly selected from schools in Urumqi city, China. WC, height, and weight were accurately measured in all subjects. Blood pressure, fasting lipids, glucose, and insulin were determined in 258 overweight/obese children and 370 age-, gender-, and ethnicity-matched normal-weight controls selected from the same study sample. LMS (lambda-mu-sigma) method was used to construct WC centile curves. Optimal WC cutoffs were determined by comparing the performance of five sets of WC cutoffs in predicting CV risk factors.


RESULTS
Han boys and girls had higher WC at all percentiles and ages except for girls over the age of 16. Uygur girls also showed a greater increase in WC corresponding with age (2.1 cm/year vs. 1.6 cm/year for the median) than Han girls. Compared with the other four sets of cutoffs, the 85th WC percentile showed the best combination of sensitivity (81.0%) and specificity (71.4%). The two sets of WC cutoffs constructed by allowing centile curves passing through the adult cutoffs for central adiposity using the fitted LMS curves provided poor sensitivities in predicting the presence of cluster of CV risk factors.


CONCLUSIONS
The growth pattern of WC varies with gender and ethnicity. The 85th percentile of WC is an appropriate cutoff for Chinese Han and Uygur children in the prediction of CV risks.
Yan
Weili
W
Division of Epidemiology and Biostatistics, School of Public Health, Xinjiang Medical University, Urumqi, Xinjiang, China. yanweili01@yahoo.com.cn
Yao
Hua
H
Dai
Jianghong
J
Cui
Jun
J
Chen
Yan
Y
Yang
Xiaoyan
X
Harshfield
Gregory A
GA
Wang
Xiaoling
X
D000293:Adolescent; D017677:Age Distribution; D000367:Age Factors; D044466:Asian People; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure; D001827:Body Height; D049628:Body Size / Q000208:ethnology*; D001835:Body Weight; D002318:Cardiovascular Diseases / Q000208:ethnology / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D016022:Case-Control Studies; D002648:Child; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D009765:Obesity / Q000150:complications / Q000208:ethnology* / Q000378:metabolism / Q000503:physiopathology; D050177:Overweight / Q000150:complications / Q000208:ethnology* / Q000378:metabolism / Q000503:physiopathology; D012016:Reference Values; D012307:Risk Factors; D017678:Sex Distribution; D012737:Sex Factors
D001786:Blood Glucose; D007328:Insulin; D008055:Lipids