Abstract

RACHED-PAOLI, Ingrid  and  HENRIQUEZ-PEREZ, Gladys. Effectiveness of the Body Mass Index in the nutritional diagnosis of pregnant adolescents. ALAN [online]. 2010, vol.60, n.2, pp.141-147. ISSN 2309-5806.

The purpose of this study was to analyze the diagnostic capacity of different classification criteria based on Body Mass Index in the assessment of nutritional status and to evaluate their effectiveness. The sample comprised 367 healthy pregnant adolescents in their first trimester of gestation, from a socioeconomic level IV, between Oct. 1999 and Dec. 2008. Two methodologies were applied for the nutritional classification: 1. Integral nutritional diagnosis (gold standard), and 2. Body Mass Index (BMI), using local reference values: Proyecto Venezuela and the Transversal Study of Caracas, and international reference values: Frisancho and WHO 2006. Concordances, kappa, sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, and the Youden index were calculated. According to the gold standard and BMI, the percentage of well-nourished pregnant women ranged between 62.4% and 80.6%. Within the deficit range, Frisancho was the most effective with kappa: 0.80; sensitivity: 87.3%; specificity: 94.8%; positive likelihood ratio: 16.9, and negative likelihood ratio: 0.13; Youden index: 0.82. Within the excess range, Frisancho and the Transversal Study of Caracas were the most effective with Youden index: 0.86 and 0.83, respectively. These results revealed that Frisancho was the best criterion to diagnose malnutrition in deficit in pregnant women. All references have an adequate diagnostic capacity for the excess range, of which Frisancho and the Transversal Study of Caracas are the best. We recommend using such reference values to optimize the efficiency of the BMI indicator in diagnosing malnutrition in deficit and in excess in the first trimester of gestation in pregnant adolescents within populations with similar characteristics.

Keywords : Pregnant; anthropometry; tennage; body mass index; classification criteria.