[Waist-to-height ratio as a predictor of blood pressure in Mexican children.  Follow-up study]. 
To assess the effect of increased waist-to-height ratio (WHtR) on the development of high blood pressure or hypertension in Mexican children.  313 preschoolers followed for one year.  We measured height and waist circumference (WC) and calculated the WHtR (cm WC/cm height).  Blood pressure was obtained with a mercury sphygmomanometer.  Children were classified with high blood pressure according to the fourth report of diagnosis, evaluation and treatment of high blood pressure in children and adolescents.  We assessed longitudinally the impact of body mass indicators (body mass index, WC and total fat) and WHtR on the development of high pressure in separate models.  Longitudinal analysis was performed with random effects using Husman test for assessing the adequacy of the model.  WHtR 1.75 unit increased the risk of hypertension.  The WHtR is a better predictor of hypertension compared to BMI and WC in preschool children followed over time.