Results of blood pressure screening in a population of school-aged children in the province of Milan: role of overweight

Abstract

To study the prevalence of high blood pressure (BP) in an Italian paediatric population, and to verify whether in this population elevated BP values are associated with overweight (OW). Children (1206 males, 1210 females) from the lower-grade public schools (ages 6-11 years) were studied. Body weight, height and BP were measured in each child. Elevated BP was defined if resting systolic and/or diastolic BP values equalled or exceeded the 95th percentile according to gender, age and height, based on the US normative BP tables. Overweight children were identified using four different methods: (1) the classification based on the relative body weight; (2) the French references by Rolland-Cachera et al. (Am J Clin Nutr 1982; 36:178-184); (3) the International Obesity Task Force charts; and (4) the Italian charts defined by Cacciari et al. (Eur J Clin Nutr 2002; 56:171-180). The prevalence of high BP in our population was 4.2% and was significantly higher in females (65/1210 = 5.4%) than in males (37/1206 = 3.1%), P = 0.005. The different methods used to define OW provide different estimates of OW prevalence (from 17.0 to 38.6%). The percentage of high BP subjects was significantly higher in OW than in normal-weight children regardless of the method used for the definition of the weight class (P < 0.0001), in both genders. In addition, for each age range, absolute systolic and diastolic BP values were higher in OW as compared to normal-weight children both in males and in females (P < 0.0001). Our study indicates the importance of performing BP screenings in the paediatric population, and to promote interventions that may reduce the prevalence of OW in children.