Department of Biomedical Technology, Faculty of Health and Wellness Sciences, Cape Peninsula University of Technology, Cape Town, South Africa.
PLoS One. 2013 Aug 13;8(8):e71133. doi: 10.1371/journal.pone.0071133. eCollection 2013.
The proposed waist-to-height ratio (WHtR) cut-off of 0.5 is less optimal for cardiometabolic risk screening in children in many settings. The purpose of this study was to determine the optimal WHtR for children from South Africa, and investigate variations by gender, ethnicity and residence in the achieved value.
Metabolic syndrome (MetS) components were measured in 1272 randomly selected learners, aged 10-16 years, comprising of 446 black Africans, 696 mixed-ancestry and 130 Caucasians. The Youden's index and the closest-top-left (CTL) point approaches were used to derive WHtR cut-offs for diagnosing any two MetS components, excluding the waist circumference.
The two approaches yielded similar cut-off in girls, 0.465 (sensitivity 50.0, specificity 69.5), but two different values in boys, 0.455 (42.9, 88.4) and 0.425 (60.3, 67.7) based on the Youden's index and the CTL point, respectively. Furthermore, WHtR cut-off values derived differed substantially amongst the regions and ethnic groups investigated, whereby the highest cut-off was observed in semi-rural and white children, respectively, Youden's index0.505 (31.6, 87.1) and CTL point 0.475 (44.4, 75.9).
The WHtR cut-off of 0.5 is less accurate for screening cardiovascular risk in South African children. The optimal value in this setting is likely gender and ethnicity-specific and sensitive to urbanization.
在许多情况下，建议的腰高比（WHtR）截断值 0.5 对于儿童的心血管代谢风险筛查不太理想。本研究的目的是确定南非儿童的最佳 WHtR，并研究在实现该值时性别、族裔和居住地的差异。
在 1272 名随机选择的 10-16 岁学习者中测量了代谢综合征（MetS）成分，其中包括 446 名非洲黑人、696 名混合血统和 130 名白种人。使用 Youden 指数和最接近左上角（CTL）点方法来推导 WHtR 截断值，用于诊断除腰围外的任何两种 MetS 成分。
两种方法在女孩中得出相似的截断值，0.465（敏感性 50.0，特异性 69.5），但在男孩中得出两个不同的值，0.455（42.9，88.4）和 0.425（60.3，67.7）基于 Youden 指数和 CTL 点。此外，在所研究的地区和族裔群体中，WHtR 截断值的差异很大，其中半农村和白人儿童的截断值最高，分别为 Youden 指数 0.505（31.6，87.1）和 CTL 点 0.475（44.4，75.9）。
0.5 的 WHtR 截断值对于南非儿童心血管风险筛查不太准确。在这种情况下，最佳值可能因性别和族裔而异，并且对城市化敏感。
