Tracking of blood pressure during childhood: the Muscatine Study

Frequency of Elevated Blood Pressure Associated With Physical Activity and Dietary Patterns among School Going Adolescents in Karachi: A Cross Sectional Survey

Background: Studies have suggested that atherosclerotic changes take place in the body since childhood due to altered dietary patterns and sedentary lifestyle. It is critical to identify gap areas and update current literature to produce effective changes in our lifestyle. Study design: A cross-sectional survey conducted among school going adolescents in Karachi. Methods: A cross sectional study was performed in three different schools of Karachi. A sample size of 288 was drawn through non-probability, purposive sampling technique. Students were given a questionnaire comprising of questions regarding their physical activity levels, dietary patterns and knowledge regarding blood pressure. Blood pressure and Body Mass Index data was also recorded. Results: Mean age of participants was 14.10 ± 1.097. Of the 288 students that participated in this study (122 boys and 166 girls), 227 were normal for hypertension status (93 boys and 134 girls), 27 were pre-hypertensive (7 boys and 20 girls), and 34 were hypertensive (22 boys and 12 girls). Mean systolic blood pressure was 112.73 ± 13.49, and mean diastolic blood pressure was 71.25 ± 13.03. Awareness among participants was high regarding hypertension being linked to the foods they consumed (62.8%). Conclusion: Our study did not show strong correlation between physical activity and dietary patterns, with status of hypertension. Screening programs should be conducted in schools to monitor blood pressure and body mass index. High risk groups should be approached and advised for lifestyle modification.. Keywords: hypertension, adolescents, life style,

Elevated Blood Pressure and Its Associated Risk Factors among Adolescents of a North Indian City - A Cross-sectional Study

Context:

Amidst the uncertainty in childhood blood pressure (BP) thresholds, besides the ambiguity in levels and duration of BP elevation causing organ damage, hypertension is present in substantial number of asymptomatic children and adolescents with only a few studies disclosing the setup. With projection of deaths due to noncommunicable diseases in 2030 rising to 52 million, it is necessary to know about the knowledge of present adolescents about BP and its modifiable risk factors.

Aims:

(1) To assess the prevalence of elevated BP among adolescents and to ascertain the associated risk factors. (2) To assess adolescent's knowledge about BP and its modifiable factors.

Settings and Design:

A community-based cross-sectional study was conducted on school going adolescents of Lucknow, from September 2014 to August 2015.

Subjects and Methods:

BP, height, and weight were measured following standard protocols, Centers for Disease Control and Prevention charts for finding respective cut-off values and oral questionnaire for assessing lifestyle risk factors were used.

Statistical Analysis:

Chi-square, unpaired t-test, and logistic regression were used.

Results:

Of the 1041 participants, elevated BP (BP percentile ≥90) was prevalent in 24.2%. On regression, factors such as obesity (adjusted odds ratio [aOR] = 5.8, 95% confidence interval [CI] = 3.6–9.4), low fruit diet (aOR = 3.3, 95% CI = 2.1–5.4), and frequent junk food consumption (aOR = 1.9, 95% CI = 1.3–2.8) raised the odds of elevated BP while it was lowered by being physically active (aOR = 0.67, 95% CI = 0.46–0.97). Of 86.3% of children (n = 898) who were fathomed of BP, only less than third (33% and 21.9%) acquainted of BP raising and lowering practices, respectively.

Conclusions:

Prevalence of high BP is colossal with only a few children knowing its amendable nature. Strenuous efforts targeting detrimental behaviors and imparting the sense of healthy lifestyle enhancing practices are vital to control this epidemic.

Gender and obesity modify the impact of salt intake on blood pressure in children

BACKGROUND

Most modifiable risk factors for high blood pressure (BP), such as obesity and salt intake, are imprinted in childhood and persist into adulthood. The aim of our study was to evaluate the intake of salt in children and to assess its impact on BP taking into account gender and nutritional status.

METHODS

A total of 298 children aged 8-9 years were evaluated in a cross-sectional study. Anthropometric measurements and 24-h ambulatory monitoring were performed, and salt intake was determined by 24-h urinary sodium excretion.

RESULTS

The average estimated salt intake among the entire cohort of children enrolled in the study was 6.5 ± 2.2 g/day, and it was significantly higher in boys than in girls (6.8 ± 2.4 vs. 6.1 ± 1.9 g/day, respectively; p = 0.018) and in overweight/obese children than in normal weight children (6.8 ± 2.4 vs. 6.1 ± 2.0 g/day, respectively; p = 0.006). Salt intake exceeded the upper limit of the US Dietary Reference Intake in 72% of children. Daytime systolic BP increased by 1.00 mmHg (95% confidence interval 0.40-1.59) per gram of daily salt intake in overweight/obese boys, but not in normal weight boys or in girls.

CONCLUSIONS

Our results demonstrate an extremely high salt intake among 8- to 9-year-old Portuguese children. Higher salt intake was associated with higher systolic BP in boys, specifically in those who were overweight/obese. Longitudinal studies are needed to further evaluate the causal relationship between obesity and high BP and the mechanism by which salt intake modulates this relationship. Nonetheless, based on our results, we urge that dietary salt reduction interventions, along with measures to fight the global epidemic of obesity, be implemented as early in life as possible.

Cardiovascular target organ damage could have been detected in sustained pediatric hypertension

The aim of this study was to assess sustained hypertension in children and its impact on cardiovascular target organ damage (TOD). Blood pressure (BP) was measured in children in Beijing in 2009. Primary hypertension was diagnosed based on three separate visits. Hypertensive children and normotensive children were followed up in 2011. According to these evaluations, three groups were defined: sustained hypertension, non-sustained hypertension and normotensive. Cardiovascular TOD and metabolic disorders were evaluated using pulse-wave velocity (PWV), carotid intima-media thickness (cIMT), and assessments of left ventricular structure and kidney function. A total of 3032 children aged 9-15 years participated in this survey, of whom 128 were diagnosed with hypertension after three separate BP measurements. Eighty out of 128 (62.5%) hypertensive and 158 normotensive children were available for follow-up in 2011. Forty-eight children were defined as having sustained hypertension, 38 as non-sustained hypertension and 152 as normotensive. Mean levels of brachial-ankle PWV (baPWV), left ventricular mass, left ventricular mass index (LVMI) and cIMT were significantly different between the three groups (p < 0.01). Compared to normotensives, the odds ratios and 95% confidence intervals for elevated LVM and cIMT were 5.27 (1.57-17.66) and 2.88 (1.03-8.09) in the non-sustained hypertensive group, and 3.28 (1.00-10.74) and 7.25 (2.69-19.58) in the sustained hypertensive group. The children with sustained hypertension have the highest risk of developing arterial stiffness, left ventricular hypertrophy and early blood vessel endothelium damage. The indices of cIMT, LVMI and PWV were useful to identify children at high risk of cardiovascular TOD.

Children and adolescents with obesity-associated high blood pressure

Hypertension and obesity are both common health problems in children and adolescents. More than 17% of children are obese and even more children are overweight. Hypertension, although defined differently in children than in adults, can be detected in 3% to 4% of children, and approximately 30% of obese adolescents have high blood pressure (BP) associated with obesity. Children with high BP and obesity frequently have other risk factors that are components of the metabolic syndrome. Evidence of target organ damage, including left ventricular hypertrophy, is detectable in many children with hypertension and is more commonly found in children with high BP and obesity. Both obesity and hypertension are considered inflammatory conditions. There are some emerging data in the young that show an association of insulin resistance, obesity, and high BP with inflammatory markers. Children and adolescents with hypertension and especially obesity-associated hypertension can be identified and should be evaluated for additional metabolic risk factors. Considering the heightened risk for premature cardiovascular (CV) disease, therapeutic interventions, including lifestyle changes and medications, when indicated, are important for all children and adolescents with obesity-associated hypertension.

Is family history a useful tool for detecting children at risk for diabetes and cardiovascular diseases? A public health perspective

Several studies indicate that the risk for type 2 diabetes or cardiovascular disease is detectable in childhood, although these disorders may not emerge until adulthood. In addition, type 2 diabetes and cardiovascular disease seem to share risk factors, including obesity and dyslipidemia, and might even share etiology, which has important implications for screening and prevention strategies for both diseases. Primary prevention, in particular, has gained importance because the results of major randomized, controlled trials strongly suggest that, at least in high-risk adult groups, type 2 diabetes can be prevented or delayed. Furthermore, some intervention studies indicate that the risk factors for diabetes and cardiovascular disease can be reduced in children. A simple way to detect risk for either diabetes or cardiovascular disease is to examine the family history. Numerous studies have shown that adults who have 1 or more first- or second-degree relatives affected with diabetes or cardiovascular disease are at high risk of having or developing these diseases. Currently, there are no overall screening strategies recommended for either diabetes or cardiovascular disease among children and adolescents. The evidence is strong, however, that youth with a positive family history already show signs of increased risk for these conditions. Family history can be part of the approach to screening for children at risk of diabetes and cardiovascular disease and should be part of prevention campaigns aimed at reducing the burden of these diseases and their risk factors in children.

Feeding in infancy: short- and long-term effects on cardiovascular function

Cardiovascular responses of adult organisms to feeding are well characterized and, in general, are understood as acute adaptations required for processing and distributing nutrients. Research over the past several years has shown that infants also have important cardiovascular responses to nutrient intake and that these are regulated by changes in autonomic activity to the heart and vasculature. Recent studies have provided results that suggest these responses in infancy may make an important contribution to the long-term development of cardiovascular function, in particular, adult blood pressure (BP). The purpose of this presentation will be to review the evidence that has led to this conclusion, offer ideas about how this potential early-life shaping of subsequent cardiovascular function may come about, and suggest further studies that will be required in order to characterize the mechanisms responsible for these effects.

Blood pressure development in F2 rats derived from SHR and WKY progenitors

In adult humans blood pressure measurements taken at one point in time are significantly correlated with subsequent measurements. However, during development, 'tracking' of blood pressures is relatively poor thus, accurate prediction of hypertension can only be made much later in life. To find better early life predictors of adult hypertension, studies using the F2 generation of rats derived from spontaneously hypertensive (SHR) and normotensive Wistar Kyoto (WKY) grandparents have been initiated. Characteristics of blood pressure development in the F2 population suggest they will be a suitable model for this goal. F2s express a wide range of adult blood pressures but, as is the case in humans, stability of individual ranking within the population, is not present until after puberty. Other results indicate that adult body weight, heart rate, and temperature are not genetically linked to SHR hypertension, and that measurement of these variables early in life, with the possible exception of body weight early in life, can not be used to predict adult hypertension.

Predictors of blood pressure and hypertension in Tecumseh, Michigan

Correlates of present blood pressure status are analyzed in 576 subjects (271 males, average age 32 years) in Tecumseh, Michigan. In addition to the current values, anthropometric and blood pressure data are available when the subjects were, on average, 6.9 and 22.2 years of age. Data on 351 fathers and 368 mothers when they were, on average, 32 years old are also available. Moderate, but significant correlations were found between present and past blood pressure and between past weight or skinfold thickness and the present blood pressure. These correlations were much weaker for childhood values than for values at age 22. When multiple regression techniques were used with blood pressure values at age 22 and parental values as independent variables, 40% of the present systolic blood pressure variance could be explained. Prediction of present hypertension status (blood pressure greater than 140 and/or 90 mm Hg) was evaluated by discriminant analysis. Three variables (weight at age 22, systolic blood pressure at age 22, and father's diastolic blood pressure) entered the model and accurately predicted the present blood pressure classification in 89% of the sample. When current blood pressure status was assessed with respect to previous blood pressure classification (upper 20%), family background, and overweight, a gradient of risk for hypertension was found. On the low end of risk was high childhood pressure (risk 19.1% versus 12.1% in the overall population). The highest risk occurred for those with high pressure and overweight at 22 years who also had a family background of high blood pressure (44% versus 12.1%). The prediction of hypertension from young adulthood to the early fourth decade of life is feasible and permits delineation of populations targeted for primary prevention.