Vieira Ana Carolina R, Alvarez Marlene M, Kanaan Salim, Sichieri Rosely, Veiga Gloria V
Programa de Pós-Graduação em Nutrição, Instituto de Nutrição Josué de Castro, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
Rev Saude Publica. 2009 Feb;43(1):44-52. doi: 10.1590/s0034-89102008005000062. Epub 2008 Oct 31.
To determine the best cut-offs of body mass index for identifying alterations of blood lipids and glucose in adolescents.
A probabilistic sample including 577 adolescent students aged 12-19 years in 2003 (210 males and 367 females) from state public schools in the city of Niterói, Southeastern Brazil, was studied. The Receiver Operating Characteristic curve was used to identify the best age-adjusted BMI cut-off for predicting high levels of serum total cholesterol (> or =150 mg/dL), LDL-C (> or =100 mg/dL), serum triglycerides (> or =100 mg/dL), plasma glucose (> 100 mg/dL) and low levels of HDL-C (< 45 mg/dL). Four references were used to calculate sensitivity and specificity of BMI cut-offs: one Brazilian, one international and two American.
The most prevalent metabolic alterations (>50%) were: high total cholesterol and low HDL-C. BMI predicted high levels of triglycerides in males, high LDL-C in females, and high total cholesterol and the occurrence of three or more metabolic alterations in both males and females (areas under the curve range: 0.59 to 0.67), with low sensitivity (57%-66%) and low specificity (58%-66%). The best BMI cut-offs for this sample (20.3 kg/m(2) to 21.0 kg/m(2)) were lower than those proposed in the references studied.
Although BMI values lower than the International cut-offs were better predictor of some metabolic abnormalities in Brazilian adolescents, overall BMI is not a good predictor of these abnormalities in this population.
确定用于识别青少年血脂和血糖变化的最佳体重指数临界值。
对2003年来自巴西东南部尼泰罗伊市公立学校的577名12 - 19岁青少年学生（210名男性和367名女性）的概率样本进行了研究。采用受试者工作特征曲线来确定用于预测血清总胆固醇（≥150 mg/dL）、低密度脂蛋白胆固醇（≥100 mg/dL）、血清甘油三酯（≥100 mg/dL）、血浆葡萄糖（>100 mg/dL）高水平以及高密度脂蛋白胆固醇（<45 mg/dL）低水平的最佳年龄调整体重指数临界值。使用了四个参考文献来计算体重指数临界值的敏感性和特异性：一个巴西的、一个国际的和两个美国的。
最常见的代谢改变（>50%）为：高总胆固醇和低高密度脂蛋白胆固醇。体重指数预测男性甘油三酯高水平、女性低密度脂蛋白胆固醇高水平以及男性和女性高总胆固醇和三种或更多代谢改变的发生（曲线下面积范围：0.59至0.67），敏感性低（57% - 66%）且特异性低（58% - 66%）。该样本的最佳体重指数临界值（20.3 kg/m²至21.0 kg/m²）低于所研究参考文献中提出的临界值。
尽管低于国际临界值的体重指数值能更好地预测巴西青少年的某些代谢异常，但总体而言，体重指数并非该人群这些异常的良好预测指标。
