The distribution of the indicator height for age of Mexican children and adolescents with Down syndrome according to different reference standards.

OBJECTIVE To compare the indicator height for age in Mexican children with Down Syndrome (DS) with two different reference patterns of growth (American and Spanish) that might be suitable for the Mexican population. METHODS A cross-sectional study was performed including 235 Mexican children and adolescents of both sexes with DS aged 45 days to 16 years enrolled in two specialized schools in the metropolitan area of Guadalajara. The dependent variables were weight/age; height/age; weight/ height and BMI. The data expressed was percentiles and the chi-square test was used to compare the distribution of the height/age index with American and Spanish reference patterns. In addition, a chi-square test was performed for the goodness of fit of the height/age index, with breakpoints lower and greater than the 50th percentile. RESULTS The percentage of participants who were below the 50th percentile in the height/age index was significantly higher with the Spanish vs. the American reference pattern. The chi-square test for goodness of fit showed that the frequency of cases located below the 50th percentile in the height/age index was significantly higher with the American pattern in the age groups of 0 to 36 months (p = 0.022) and 37 to 72 months (p <0.001), but it was not significant (p = 0.225) in the older than 72 months age group. CONCLUSION The American reference pattern is a better fit for the growth of Mexican children with DS compared with the Spanish reference pattern, and the distribution profile obtained with the standard growth and WHO reference was not suitable for the assessment of children with Down syndrome.