Search

The objective of this study was to assess the degree of BP Tracking from childhood to adulthood and to evaluate whether high BP levels persist over time and progress to adult hypertension.Two hundred and twenty-two healthy schoolchildren living in the North of Portugal were assessed at 17 year intervals, starting in 1979 (cohort 1) aged 5 to 18 years, and again in 1996 (cohort 2). Tracking indices (Ti) were calculated as follows: Ti = (2x + y-z) /N/0.89, where x, y and z refer to the total number in the same, adjacent and remote trisections, respectively, and N = x + y + z. If Ti1 there is positive tracking.For systolic and diastolic blood pressure, all Ti were greater than 1.0. All individuals that remained in the 3rd tertil, 17 years later, weigh more and are more obese than those of the 1st tertil. 56.6% of the individuals that belong to the 3rd tertil are now hypertensive, which means that a significant percentage of the children with high blood pressure in the first survey will be hypertensive in the future.

Many studies have assessed the blood pressure tracking among children and adolescents, but the results have been controversial. This study assessed the blood pressure tracking in 224 Portuguese school children and young adults following them for 17 years. The correlations obtained for systolic and diastolic blood pressure in both sexes are not very high, although positive and statistically significant. On the other hand, there was a stronger correlation between anthropometric variables and blood pressure and indices of obesity.

The aim of our study is to evaluate whether factor analysis is better able to explain the variability of systolic blood pressure (SBP) and diastolic blood pressure (DBP) when compared with regression analysis, which is the usual tool to study a set of variables related to blood pressure (BP). SBP, DBP, weight, height, BMI, triceps skin-fold, sexual maturation and rurality were studied in 889 children aged 5-18 years (389 boys and 500 girls). The proposed method transforms any set of variables into a set of new variables (factors) which are uncorrelated with each other. One of the factors obtained clearly explains the BP variance of the. With this method, the algorithm accepts all meaningful variables, while regressions reject most of them. This method also explains a larger amount of BP variability, losing as little information as possible. In our sample the percentage of the total variance (communality) explained by the three factors was 80.3% for SBP, 88.1% for DBP in males, 79.3% for SBP and 90.7% for DBP in females. For the same sample, regressions only explained 41.2% in males and 41.9% in females for SBP, 40.9% in males and 47.2% in females for DBP. In conclusion, this method is more accurate for epidemiological studies producing a better overall score than regression analysis, losing almost no information from the sample. Two important strengths of the proposed methodology are as follows. First, it yields a unique, easy to calculate and flexible cardiovascular index for children, thus circumventing the problem of making decisions based on two variables (SBP and DBP). Second, such an index is the result of a methodology where specific BP variability is isolated rather than explained.

Obesity is associated with high blood pressure BP, mainly in adults. It has been suggested that body fat patterning plays a role in the etiology of hypertension. This relationship also exists in children, however it is less well known. The aim of this study was to evaluate the prevalence of high blood pressure (HBP) in children and adolescents, and the influence of obesity on this population, as well as the presence of familial aggregation for these factors. Eight hundred and eighty-nine children (389 boys and 500 girls aged 5-18 years) and their parents, from the North of Portugal were studied. Systolic blood pressure, diastolic blood pressure, weight, height, triceps skinfold, body mass index and sexual maturation were measured. The criterion of high blood pressure was defined as the BP being higher than the 90th percentile. All variables were converted to age and sex in specific "Z-scores". A SPSS package was used. We found 47 (5.2%) people of both sexes to have high blood pressure. The children of this group were compared with the normotensive group. These children were heavier (p0.005) and more obese (p0.0001) than the others. No difference was found for sexual maturation or height. The parents of the group with high blood pressure were heavier (p0.001) and more obese (p0.01) than the parents of the normotensive group. In conclusion, obesity is an important factor in children with higher values. Children with HBP are more likely to come from families with history of obesity. The identification of these risk factors in children is an important contribution to the prevention of cardiovascular disease in adulthood.

A study was undertaken to determine whether parent-child blood pressure (BP) resemblances reflect parent-child similarities in body build. Those studied were 889 children, 5-18 years old, their parents and relatives because of recognized correlations between body build and BP in individuals, along with familial clustering of these variables. To maximize the likelihood of demonstrating correlations between BP and body build in family members, BP and anthropometric variables of parents whose children were in the upper quintile (group I) and lower quintile (group II) of the same variables were compared. Variance analysis has shown that group I children were heavier (P less than or equal to 0.001) and more obese (P less than or equal to 0.01) than group II. The parents of group I had higher systolic BP (P less than or equal to 0.001), diastolic BP (P less than or equal to 0.01), were taller (P less than or equal to 0.0001), heavier (P less than or equal to 0.001) and more obese (P less than or equal to 0.01), than the parents of group II. Parent-children BP resemblances reflect parent-children similarities in body build. The study of group I children and their families may give important information about determinants of high BP in children.