Relationship of age at menarche and serum leptin with the metabolically unhealthy phenotype in adolescents Translated title: Relación de la edad de la menarquia y la leptina sérica con el fenotipo metabólicamente no saludable en adolescentes

Abstract

Abstract Objective: to analyze the relationship of age at menarche and leptin with the metabolically healthy (MH) and metabolically unhealthy (MUH) phenotypes in adolescent girls in different body mass index (BMI) categories. Method: an observational and cross-sectional study consisting of 139 female adolescents attended to at the Adolescent Reference Center in Macaé, Rio de Janeiro.: Menarche was classified as early (EM) when the first menstruation occurred at or before 11 years of age; normal menarche (NM) was categorized at ages 12 to 14; menarche was considered late (LM) when it occurred at age 15 or older. The factors required to ascertain the subjects' phenotype, as well as their leptin levels, weight, and height, were measured and their BMIs were calculated. The girls were classified as MH or MUH based on the NCEP-ATP III criteria as adapted for children and adolescents. Results: 82 % (n = 114) of the girls were classified as MH and 18 % (n = 25) as MUH. Mean age at menarche was 11.79 ± 1.39 years. There was a higher prevalence of MUH amongst the girls who had EM (p = 0.04). A higher inadequacy of serum leptin concentrations was found in girls who had EM (p = 0.05) and in those classified as MUH (p = 0.01). The adolescents who were severely obese exhibited inadequate leptin levels (p < 0.01) and had gone through EM (p = 0.02). A total of 8.1 % (n = 7) of the normal-weight girls were classified as MUH, and 29.4 % (n = 5) of those who were severely obese were classified as MH (p < 0.01). Conclusion: early menarche and high serum leptin concentrations are related with the MUH phenotype in adolescent girls in different BMI categories.

Translated abstract

Resumen Objetivo: analizar la relacion de la edad de la menarquia y los niveles de leptina con los fenotipos metabolicamente saludables (MS) y metabolicamente no saludables (MNS) en adolescentes de diferentes categorias de indice de masa corporal (IMC). Método: estudio observacional y transversal compuesto por 139 adolescentes de sexo feminino, atendidas en el Centro de Referencia para Adolescentes de Macae, Rio de Janeiro. La menarquia se clasifico como precoz (MP) cuando se produjo la primera menstruacion a o antes de los 11 anos de edad; la menarquia normal (MN) se clasifico como aquella sucedida a la edad de 12 a 14 anos; la menarquia se consider tardia (MT) cuando ocurrio a los 15 anos o mas. Se midieron los factores necesarios para determinar el fenotipo de los sujetos, y se midieron sus niveles de leptina, peso y altura, y se calculo su IMC. Las adolescentes se clasificaron como MS y MNS segun los criterios de NCEP-ATP III, adaptados para ninos y adolescentes. Resultados: el 82 % (n = 114) de las adolescentes se clasificaron como MH y el 18 % (n = 25) como MUH. La edad media de la menarquia fue de 11,79 ± 1,39 anos. Hubo una mayor prevalencia de MUH entre las adolescentes que tenian MP (p = 0,04). Se encontro una mayor insuficiencia de las concentraciones sericas de leptina en las adolescentes que tenian MP (p = 0,05) y en aquellas clasificadas como MNS (p = 0,01). Las adolescentes que eran severamente obesas exhibieron niveles inadecuados de leptina (p < 0,01) y habian pasado por una MP (p = 0,02). El 8,1 % (n = 7) de las adolescentes de peso normal se clasificaron como MNS y el 29,4 % (n = 5) de las que eran severamente obesas se clasificaron como MS (p < 0,01). Conclusión: la menarquia temprana y las altas concentraciones sericas de leptina estan relacionadas con el fenotipo MNS en las adolescents de diferentes categorias de IMC.