INTRODUCTION Hypertension is one of the most studied risk factors for cardiovascular disease in adults; in children and adolescents, its global prevalence changes with age, from 1%–3% in children to 3.2% in adolescents. In adults, in addition to hypertension, several biochemical markers of cardiovascular risk have been identified. Confirming an association between these and hypertension in childhood and adolescence would allow for more timely diagnosis and monitoring of cardiovascular disease, since the presence of both the markers and hypertension would imply increased risk.
OBJECTIVE Confirm an association between biochemical risk markers of cardiovascular disease and hypertension in children aged 8 to 11 years.
METHODS A cross-sectional study of 373 children aged 8–11 years was conducted in 3 primary schools in the city of Santa Clara in central Cuba. The variables examined were age, sex, height, blood pressure, cholesterol, triglycerides, lipoproteins and apolipoproteins. The children were classified as normotensive, prehypertensive or hypertensive, based on blood pressure readings and percentiles for age, sex and height. Descriptive statistics were calculated for quantitative variables. A bivariate analysis, tests of independence for qualitative variables and a means comparison for quantitative variables (ANOVA and its nonparametric alternative, the Kruskal Wallis test) were performed. Fisher’s F-test and its associated probability value were employed.
RESULTS Some 32.2% of the children were prehypertensive and 5.1% hypertensive. Cholesterol and triglyceride values were significantly higher in hypertensive than in normotensive children (p = 0.028 and p = 0.047, respectively). HDL numbers were higher in normotensive children (p =0.001), and LDL numbers and the LDL/HDL ratio were higher in the hypertensive children, with differences between groups (p = 0.001 for both variables). There were differences between the three blood pressure categories for lipoprotein(a) and ApoA (p <0.001 and p = 0.001), for ApoB and for the ApoB/ApoA ratio (p <0.001 for both variables), with lower ApoA values and higher ApoB and ApoB/ApoA values in the hypertensive children.
CONCLUSIONS The biochemical risk markers most strongly associated with hypertension in children are ApoB values, LDL, lipoprotein(a), and LDL/HDL and ApoB/ApoA ratios.
KEYWORDS Adolescent, child, hypertension, apolipoproteins, cardiovascular diseases, risk factors, Cuba
INTRODUCTION Hypertension and obesity in adults have been linked to increased EKG P-wave dispersion; the association has been shown in relation to hypertension, left ventricular hypertrophy and atrial enlargement. Though studies in children have linked P-wave dispersion to left ventricular hypertrophy, scant pediatric literature relates P-wave dispersion to hypertension and obesity.
OBJECTIVE Assess the association of P-wave dispersion with blood pressure and nutritional status in a pediatric population.
METHODS This cross-sectional study is part of the PROCDEC II project for pediatric hypertension diagnosis and control in Santa Clara, Cuba. Twelve-lead EKG and four blood pressure readings were conducted on a sample of 656 children aged 8–11 years. Blood pressure <90th percentile for age, sex and height was considered normal; 90th–95th percentile, prehypertension; and >95th percentile, hypertension. The main study variables were P-wave dispersion and systolic, diastolic and mean arterial pressure (MAP). Secondary variables were sex, height, weight, and body mass index. Comparisons of means, analysis of variance and linear correlations were done.
RESULTS Mean P-wave dispersion differed significantly (p ≤0.05) among normotensive (30.10 ms), prehypertensive (32.99 ms) and hypertensive children (39.14 ms), as did mean MAP (p <0.05). P-wave dispersion and MAP were significantly correlated in prehypertensive and hypertensive children. Most overweight and obese children with high P-wave dispersion were prehypertensive or hypertensive.
CONCLUSIONS Associations observed between P-wave dispersion and MAP in normotensive, prehypertensive and hypertensive children suggest potential for early detection of EKG patterns showing vulnerability. Given the relationship between increased P-wave dispersion and hypertension already described in adults, use of P-wave dispersion could be a simple, economical and noninvasive method of predicting risk of hypertensive cardiomyopathy in prehypertensive and hypertensive children; this in turn could guide timely, effective treatment and secondary prevention. Similar studies on a larger sample are needed to corroborate these results.
KEYWORDS Arterial hypertension, pediatrics, prevention, electrocardiogram, ECG, EKG, mean arterial pressure, P-wave dispersion, Cuba
