Dietary and lifestyle patterns in relation to high blood pressure in children: the GRECO study

Influence of puberty on relationships between body composition and blood pressure: a cross-sectional study

BACKGROUND

Fat mass (FM) and fat-free mass (FFM) are positively associated with blood pressure (BP) in youth. Yet, how puberty, independent of age, affects these relationships remains unclear. Given puberty may be a crucial period for cardiometabolic health, we examined how pubertal development moderates the associations of FM/FFM with BP.

METHODS

Pubertal development, resting BP, and body composition were assessed in a convenience sample of youth (5.5-17 years). General linear models were conducted to assess if pubertal development moderated the relationships between FM/FFM and systolic/diastolic BP standardized for age, sex, and height (SBPz/DBPz).

RESULTS

Among participants (N = 1405; age: M = 13.3 ± 2.9 years; 65.4% female; 53.2% racial/ethnic minority), FM/FFM were positively associated with SBPz and DBPz (ps ≤ 0.02). Pubertal development moderated the associations between FFM and BPz (ps ≤ 0.01), but not FM (ps > 0.43). For early/mid and late pubertal participants, there were positive associations between FFM and BP (DBPz: βs = 0.10-0.18, ps ≤ 0.01; SBPz: βs = 0.33-0.43, ps < 0.001); however, these relationships were attenuated, especially for prepubertal DBPz (DBPz: β = 0.01, p = 0.91; SBPz: β = 0.24, p = 0.001).

CONCLUSIONS

Puberty moderated the relationships between FFM and SBPz/DBPz in analyses that separately modeled the contributions of age and sex. These data suggest that the FFM-DBPz association may potentially be impacted by increasing sex hormone concentrations during puberty.

IMPACT

Fat mass (FM) and blood pressure (BP) were positively associated throughout puberty. Fat-free mass (FFM) and BP were positively associated throughout puberty; however, puberty moderated the FFM-BP relationship, such that there was a positive relationship in early/mid and late puberty, but the relationship was attenuated for prepubertal children. These findings contribute further insight into physiological and cardiometabolic changes occurring during puberty. Changes in hormone concentrations may explain the impact puberty has on the FFM-BP relationship. Understanding predictors of BP are important as childhood BP is associated with future cardiometabolic outcomes.

Estimation of Salt Intake in Normotensive and Hypertensive Children: The Role of Body Weight

OBJECTIVE

The connection between increased dietary salt intake and arterial hypertension has been recognized for a long time, even in children. This study aimed to investigate salt consumption in normotensive and hypertensive children and evaluate their dietary habits.

MATERIALS AND METHODS

A total of fifty participants were included in this cross-sectional study: twenty-five normotensive children and 25 children of both sexes with essential arterial hypertension from 12-17 years old. Subjects' body mass index, waist-to-hip ratio, body composition and arterial blood pressure were measured, and their daily salt intake was calculated from 24-h urine samples. Using the food frequency questionnaire (FFQ), the data on the average daily total energy and food intakes were collected and analyzed using a suitable program.

RESULTS

Estimated daily salt intake was significantly higher in hypertensive compared to normotensive children, and this is positively associated with blood pressure and body mass index (BMI). Hypertensive children had significantly higher BMIs, which also positively correlated with blood pressure. Consistently, resting metabolic rate (kcal) is higher in hypertensive children compared to normotensive, and this is also associated with blood pressure. Reported energy intake is also enlarged in hypertensive compared to normotensive children and for both groups, levels are significantly higher than the recommended values.

CONCLUSIONS

Our study results confirm the relationship between daily salt consumption, blood pressure and body weight. Sodium consumption related to blood pressure and body weight among children. Cardiovascular disease prevention should start in early childhood by reducing salt intake and preventing overweight/obesity since these are two of the most important modifiable risk factors for hypertension.

Associations of parental reproductive age and elevated blood pressure in offspring: An observational study

Background

Increased parental reproductive age has been a social trend around the world, and elevated blood pressure in children leads to an approximately two-fold increased risk of hypertension in adulthood. Aim of this study is to assess the associations of parental reproductive age with the risk of elevated blood pressure in offspring, and to explore the influence of offspring lifestyle on the associations.

Methods

Data was obtained from a national school program conducted in 7 Chinese provinces, and the final sample was 39,190 students aged 7-18 years. Anthropometric measurements and questionnaires were designed to collect data of children blood pressure and information respectively.

Results

In this study, 26.7% of children were defined as elevated blood pressure. A U-shaped pattern was observed in the relationship between maternal age and risk of elevated blood pressure, while risk of elevated blood pressure decreased continuously with paternal age increased. After adjustment, offspring of paternal age ≤27 & maternal age ≤26 years and those of paternal age >30 & maternal age >32 years were related to great risk of elevated blood pressure (OR = 1.18, 95% CI: 1.08-1.29, P < 0.001; OR = 1.18, 95% CI: 1.01-1.38, P < 0.05). When stratified by lifestyle status, significant associations between maternal/paternal age and risk of elevated blood pressure were only observed in those with worse lifestyle behaviors, but not in offspring with healthier lifestyle.

Conclusion

Our findings demonstrate that risk of elevated blood pressure in children is independently related to parental reproductive age, and children maintaining a healthy lifestyle may mitigate the adverse effect.

Exploring the Associations between Single-Child Status and Childhood High Blood Pressure and the Mediation Effect of Lifestyle Behaviors

Background: This study aimed to assess the association between single-child status and childhood high blood pressure (HBP) and to explore the role of lifestyle behaviors in this relationship. Methods: This study used data from a cross-sectional survey of 50,691 children aged 7~18 years in China. Linear and logistic regression models were used to assess the relationship between single-child status and HBP, and interactions between single-child status and lifestyle behaviors were also evaluated. Mediation analysis was conducted to detect the mediation effect of lifestyle behaviors. Results: Of the participants enrolled, 67.2% were single children and 49.4% were girls. Non-single children were associated with a greater risk of HBP, especially in girls (OR = 1.11, 95%CI: 1.03~1.19). Meat consumption and sedentary behavior mediated 58.9% of the association between single-child status and HBP (p < 0.01). When stratified by sleeping duration, non-single girls of insufficient sleep and hypersomnia showed a higher risk of HBP (p < 0.05) than single-child peers, but not in those with adequate sleep. Conclusion: Findings suggest that non-single children had an increased risk of HBP, and keeping healthy lifestyle behaviors could help to mitigate the adverse impact in non-single children.

Risk of hypertension in school-aged children undergoing a long-term community-based lifestyle intervention: Tehran Lipid and Glucose Study

Childhood hypertension which increases the risk of cardiovascular diseases in adulthood is becoming more prevalent. For the first time in the Middle-East region, this study aimed to assess the long-term effectiveness of a community-based lifestyle intervention on the incidence of hypertension in school-aged children during 16 years of follow-up. This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS). Participants were 2080 children aged 8-18 years with normal blood pressure who were under the coverage of three health care centers selected using multistage cluster random sampling method. One of the health care centers far from the other two was selected for implementing lifestyle intervention (1053 children, 48.2% boys). Triennial examinations were conducted, and survival Cox models were used to assess intervention effects on the incidence of hypertension in boys and girls. Crude incidence rates (per 1000 person-years) of hypertension were 8.11, 3.7, and 5.8 among boys, girls, and the total sample, respectively. Our results showed that HTN has occurred significantly less (P = 0.025) in the intervention group than in the control group, only in female participants. These results remained significant even after adjusting for individuals' and parental characteristics (P = 0.033). Although the risk of hypertension in boys was more than twice that observed in girls, the effectiveness of the recent community-based healthy lifestyle intervention was observed only in girls and not in boys. Further studies are needed to understand gender differences in promoting the effectiveness of similar future programs. The TLGS is registered at Iran Registry for Clinical Trials, a WHO primary registry (http://irct.ir; IRCTID: IRCT138705301058N1).

[Role of breakfast and its quality in the health of children and adolescents in Spain]

Introduction

Eating breakfast is a healthy habit that should be encouraged since childhood. When it provides nutritional quality, it is an important daily meal. The consumption of dairy products, cereals, and fruits at breakfast is associated with healthier dietary patterns, with a beneficial impact on the overall quality of the diet. In Spain, as in many other countries, the proportion of children who eat breakfast daily is very high, decreasing somewhat in adolescence. However, the quality of breakfast leaves room for improvement, with a low proportion of children/adolescents with high nutritional quality breakfasts. Children/adolescents who eat breakfast regularly have a higher intake of various nutrients (especially vitamins and minerals) than those who do not eat breakfast. Although the evidence is not entirely conclusive, numerous studies have shown various benefits when comparing the population that eats breakfast regularly versus those who do not, such as cardiometabolic risk parameters (obesity, diabetes, blood pressure and lipid profile) and cognitive functions. Breakfast should be included in healthy eating plans, since it allows incorporating foods that are difficult to consume in other meals and may contribute to reducing the risk of developing cardiometabolic diseases. In order to promote the intake of a healthy breakfast, it is essential to act on the sociodemographic and cultural factors that influence compliance and quality, such as age, nutritional education (mainly parents and children/adolescents, but also other family members, school mates, friends...), carrying it out as a family, adapting it to the tastes of each population and balancing quality and costs.

Phthalate exposure linked to high blood pressure in Chinese children

BACKGROUND

Exposure to phthalate esters may be linked to the risk of high blood pressure (HBP), but limited evidence is available in Chinese children.

OBJECTIVE

To investigate the associations between nine phthalate metabolites (mPAEs) and systolic/diastolic BP, pulse pressure (PP), mean arterial pressure (MAP), and the risk of HBP.

METHODS

In this cross-sectional study, a total of 1044 primary school children (6-8 years old) were enrolled from Shenzhen, China, between 2016 and 2017. Nine mPAEs were analyzed from urine using ultra-performance liquid chromatography and tandem mass spectrometry. A multivariable linear regression model was used to explore the associations between phthalate exposure and systolic/diastolic BP, PP, and MAP. A binary logistic regression model was used to examine the associations between phthalate exposure and the risk of HBP.

RESULTS

Monomethyl phthalate (MMP) concentrations were significantly higher in HBP children than normal BP children. MMP, monoisobutyl phthalate (MiBP), monobutyl phthalate (MnBP), mono(5-carboxy-2-ethylpentyl) phthalate, mono-[(2-carboxy methyl)hexyl] phthalate (MCMHP), the sum of four short-chain mPAEs (∑LMW), and the sum of all nine mPAEs (∑₉mPAEs) were significantly positively associated with increases in systolic BP z-score, while only MMP was significantly positively associated with diastolic BP z-score. MMP, MiBP, MnBP, MCMHP, ∑LMW, and ∑₉mPAEs were significantly associated with increases in PP, while MMP and MnBP were significantly associated with increases in MAP. MMP was significantly associated with the risk of HBP, with an odds ratio of 1.87 (95% CI: 1.23, 2.85).

CONCLUSIONS

The present study suggests that dimethyl phthalate exposure increases the risk of HBP. And some types of phthalates are associated with elevations in systolic/diastolic BP z scores, PP, and MAP in Chinese children.

Energy Dense Salty Food Consumption Frequency Is Associated with Diastolic Hypertension in Spanish Children

High blood pressure (BP) is a risk factor for cardiovascular disease and sodium consumption is related to high BP. Moreover, sugar-sweetened beverages (SSB) and the Dietary Approach to Stop Hypertension (DASH) influence BP. For this reason, we investigated whether: 1) children with risk of elevated BP had a higher consumption frequency (CF) of energy-dense salty foods (EDSF), high-sugary foods (HSF) and SSB or a low DASH score; and 2) children with a higher CF of EDSF showed a worse anthropometric and metabolic profile. Anthropometry, BP and general biochemical parameters were measured in 687 Spanish children (5-16 years) with normal or excess weight. A food frequency questionnaire was used to calculate EDSF, HSF and SSB consumption, and modified DASH score. Results showed that sex and pubertal stage influenced modified DASH score. Diastolic hypertension was associated to higher CF of EDSF in the whole sample and to higher CF of SSB in pubertal children, both independently of nutritional status. In addition, CF of EDSF was positively associated with CF of HSF and SSB and inversely associated with modified DASH score. Targeted policies and intervention programs, specific for different age ranges, should be established that aim to reduce salt consumption from snacks and processed foods, which could reduce HSF and SSB consumption as well.

Effect of Overweight and Obesity on High Blood Pressure in Chinese Children and Adolescents

OBJECTIVE

This study aimed to compare the secular trends of high blood pressure (HBP) and the effects of overweight and obesity on HBP between Chinese ethnic minority and Han children and adolescents .

METHODS

Data were collected from 224,151 Chinese ethnic minority and 664,094 Han children and adolescents aged 7 to 18 years during three successive, national cross-sectional surveys (2005, 2010, and 2014). Logistic regression and population-attributable risk analyses were used to evaluate the association between HBP and overweight and obesity.

RESULTS

HBP prevalence in ethnic minorities increased from 4.8% in 2005 to 6.3% in 2014, which was significantly higher than the variable HBP trends (4.1% to 5.5%) in Han children and adolescents. Both ethnic minority and Han children and adolescents experienced a rapid increase in overweight and obesity, but the pace of growth for HBP, overweight, and obesity was faster in ethnic minorities than in their Han peers. Moreover, the effects of obesity on HBP in ethnic minorities showed a sustained increase over time but were stable for the Han.

CONCLUSIONS

Higher HBP prevalence, faster obesity increases, and a stronger impact of obesity on HBP in children and adolescents of Chinese ethnic minorities predict their looming burden of HBP, which suggests that attention to the cardiovascular disease risks in children and adolescents from ethnic minorities is indicated to reduce their future adult risk.

Sodium intake and blood pressure in children and adolescents: a systematic review and meta-analysis of experimental and observational studies

Background

High sodium intake is a cause of elevated blood pressure in adults. In children and adolescents, less evidence is available and findings are equivocal. We systematically reviewed the evidence from experimental and observational studies on the association between sodium intake and blood pressure in children and adolescents.

Methods

A systematic search of the Medline, Embase, CINAHL and CENTRAL databases up to March 2017 was conducted and supplemented by a manual search of bibliographies and unpublished studies. Experimental and observational studies involving children or adolescents between 0 and 18 years of age were included. Random-effects meta-analyses were performed by pooling data across all studies, separately for experimental and observational studies, and restricting to studies with sodium intake and blood pressure measurement methods of high quality. Subgroup meta-analyses, sensitivity analyses and meta-regressions were conducted to investigate sources of heterogeneity and confounding. The dose-response relationship was also investigated.

Results

Of the 6572 publications identified, 85 studies (14 experimental; 71 observational, including 60 cross-sectional, 6 cohort and 5 case-control studies) with 58 531 participants were included. In experimental studies, sodium reduction interventions decreased systolic blood pressure by 0.6 mm Hg [95% confidence interval (CI): 0.5, 0.8] and diastolic blood pressure by 1.2 mm Hg (95% CI: 0.4, 1.9). The meta-analysis of 18 experimental and observational studies (including 3406 participants) with sodium intake and blood pressure measurement methods of high quality showed that, for every additional gram of sodium intake per day, systolic blood pressure increased by 0.8 mm Hg (95% CI: 0.4, 1.3) and diastolic blood pressure by 0.7 mm Hg (95% CI: 0.0, 1.4). The association was stronger among children with overweight and with low potassium intake. A quasi-linear relationship was found between sodium intake and blood pressure.

Conclusions

Sodium intake is positively associated with blood pressure in children and adolescents, with consistent findings in experimental and observational studies. Since blood pressure tracks across the life course, our findings support the reduction of sodium intake during childhood and adolescence to lower blood pressure and prevent the development of hypertension.

Obesity and season as determinants of high blood pressure in a school-based screening study

This school-based screening study assessed the prevalence of high blood pressure (BP) levels according to the European Society of Hypertension (ESH) 2016 guidelines. Moreover, risk factors for BP elevation, and the effect of geographic and seasonal factors on BP screening were investigated. BP and anthropometric measurements were obtained from 2832 children and adolescents, aged 6-18 years, during the period 2013-2016. Three BP measurements were performed using a mercury sphygmomanometer, and the mean of the last two was used for the analysis. Obesity was defined according to the International Obesity Task Force (IOTF) criteria. The prevalence of high-normal BP/hypertension and overweight/obesity was 3.7%/0.9%, and 22.9%/8.5%, respectively. The majority of the participants presenting high BP (≥90th percentile) were overweight or obese. Increased prevalence of high BP was observed during spring (5.5%) and winter (5%) compared with 2.5% in autumn (P<0.05). SBP z scores were higher in males, during spring and summer, and in urban areas. In conclusion, a low rate of high-normal and hypertensive BP levels was found despite the high prevalence of overweight and obesity. Overweight and obesity were associated with higher BP levels, but there was also a seasonal difference in the prevalence of high BP levels.

Association of dietary pattern with carotid intima media thickness among children with overweight or obesity

BACKGROUND

Since there is no evidence demonstrating the relationship between dietary patterns and subclinical atherosclerosis in children and adolescents, we aimed to examine the association between dietary patterns and carotid intima-media thickness (cIMT) in children and adolescents with overweight and obesity.

METHODS

Data were collected on individuals, aged 6-13 years (n = 339) recruited from primary schools with age- and sex-specific body mass index (BMI) Z-score > 1, based on WHO criteria. Dietary intake was assessed using a valid and reliable food frequency questionnaire and dietary patterns were derived by factor analysis. Measurement of cIMT was performed by means of ultrasonography for the wall of common carotid artery.

RESULTS

The mean ± SD age, BMI Z-score and cIMT of study participants were 9.3 ± 1.7 years, 2.5 ± 0.7 and 0.403 ± 0.057 mm, respectively. Three dietary patterns were identified, which accounted for 23.0% of the total variance, including the healthy, the traditional, and the unhealthy patterns. After adjusting for age, sex, pubertal status, smoking exposure, physical activity, body fat percentage, and intake of magnesium and energy, a significant inverse association was observed between the healthy dietary pattern and cIMT (β = - 0.131, P = 0.019), whereas none were found between cIMT and the traditional (β = - 0.004, P = 0.932) and the unhealthy dietary (β = 0.004, P = 0.942) patterns.

CONCLUSIONS

Results of the present study indicate that adherence to healthy dietary pattern could prevent increased cIMT in children and adolescents with overweight and obesity. Further cohort design research is required to elucidate the association between dietary patterns and cIMT in children and adolescents.

Correlates of elevated blood pressure in healthy children: a systematic review

The prevalence of hypertension in children is increasing globally. Addressing this will require a robust understanding of associated risk factors. To this end, we conducted a systematic review to identify correlates of elevated blood pressure (BP) in children. Literature searches were conducted using pre-defined search terms from three academic databases. The abstract and full text of identified studies were screened for eligibility by two independent reviewers. A total of 100 studies were included in this systematic review. An assessment tool was first used to assess study quality; a narrative synthesis was then performed. We found a broad range of physiological, social and behavioural factors associated with elevated BP in children. The most common correlate observed was adiposity, suggesting that childhood obesity may be implicated in the increased prevalence of hypertension observed in children. However, the broad range of other factors identified underscores the multi-factorial aetiology of hypertension. Data from a broad range of studies showed that the correlates of hypertension in children are multi-factorial. Therefore, approaches aimed at preventing hypertension must in turn be multi-factorial to ensure that the burden of hypertension in childhood is addressed.

Fast food consumption and its associations with obesity and hypertension among children: results from the baseline data of the Childhood Obesity Study in China Mega-cities

BACKGROUND

China has seen rapid increase in obesity and hypertension prevalence and fast food consumption over the past decade. We examined status and risk factors for Western- and Chinese fast food consumption and their associations with health outcomes in Chinese children, and examined how maternal factors were associated with child health outcomes.

METHODS

Data of 1626 students aged 7-16 (11.6 ± 2.0) years and their parents in four mega-cities across China (Beijing, Shanghai, Nanjing, and Xi'an) were collected in the 2015 baseline survey of the Childhood Obesity Study in China Mega-cities. Weight, height, waist circumference, and blood pressure were measured. Food intake was assessed using questionnaire. Mixed models were used to examine the associations.

RESULTS

Among the children, 11.1% were obese, 19.7% were centrally obese, and 9.0% had hypertension. Obesity prevalence was much higher in boys than in girls (15.2% vs. 6.9% and 27.4% vs. 11.7%, respectively, both P < 0.001). About half (51.9% and 43.6%) of children consumed Western and Chinese fast food, respectively, over the past 3 months. Compared to those with college or above maternal education level, those with elementary school or below maternal education level were 49% more likely to consume Western fast food (odds ratio [OR] and 95% confidence interval [CI]: 1.49 [1.10-2.03]). Chinese fast food consumption rate increased by 12% with each year of increase in child's age (OR and 95% CI: 1.12 [1.02-1.23]). No significant associations between fast food consumption and health outcomes were detected. Adjusting for Western fast food consumption, children with lower maternal education were 71% and 43% more likely to have obesity and central obesity (ORs and 95% CIs: 1.71 [1.12-2.61] and 1.43 [1.00-2.03], respectively), and maternal body mass index was positively associated with child obesity, central obesity, and hypertension (ORs and 95% CIs: 1.11 [1.06-1.17], 1.12 [1.07-1.17], and 1.09 [1.03-1.15], respectively). Results were similar when Chinese fast food consumption was adjusted for.

CONCLUSIONS

The prevalence of fast food consumption, obesity and hypertension is high among children in major cities in China. Maternal factors affect child outcomes.

Associations of Whole Blood n-3 and n-6 Polyunsaturated Fatty Acids with Blood Pressure in Children and Adolescents - Results from the IDEFICS/I.Family Cohort

Background

Polyunsaturated n-3 and n-6 polyunsaturated fatty acids (PUFA) are precursors of biologically active metabolites that affect blood pressure (BP) regulation. This study investigated the association of n-3 and n-6 PUFA and BP in children and adolescents.

Methods

In a subsample of 1267 children aged 2–9 years at baseline of the European IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) cohort whole blood fatty acids were measured by a validated gas chromatographic method. Systolic and diastolic BP was measured at baseline and after two and six years. Mixed-effects models were used to assess the associations between fatty acids at baseline and BP z-scores over time adjusting for relevant covariables. Models were further estimated stratified by sex and weight status.

Results

The baseline level of arachidonic acid was positively associated with subsequent systolic BP (β = 0.08, P = 0.002) and diastolic BP (β = 0.07, P<0.001). In thin/normal weight children, baseline alpha-linolenic (β = -1.13, P = 0.003) and eicosapentaenoic acid (β = -0.85, P = 0.003) levels were inversely related to baseline and also to subsequent systolic BP and alpha-linolenic acid to subsequent diastolic BP. In overweight/obese children, baseline eicosapentaenoic acid level was positively associated with baseline diastolic BP (β = 0.54, P = 0.005).

Conclusions

Low blood arachidonic acid levels in the whole sample and high n-3 PUFA levels in thin/normal weight children are associated with lower and therefore healthier BP. The beneficial effects of high n-3 PUFA on BP were not observed in overweight/obese children, suggesting that they may have been overlaid by the unfavorable effects of excess weight.

Water Intake in a Sample of Greek Adults Evaluated with the Water Balance Questionnaire (WBQ) and a Seven-Day Diary

Awareness on the importance of hydration in health has created an unequivocal need to enrich knowledge on water intake of the general population and on the contribution of beverages to total water intake. We evaluated in the past water intake in a sample of Greek adults using two approaches. In study A, volunteers completed the Water Balance Questionnaire (WBQ), a food frequency questionnaire, designed to evaluate water intake (n = 1092; 48.1% males; 43 ± 18 years). In study B, a different population of volunteers recorded water, beverage, and food intake in seven-day diaries (n = 178; 51.1% males; 37 ± 12 years). Herein, data were reanalyzed with the objective to reveal the contribution of beverages in total water intake with these different methodologies. Beverage recording was grouped in the following categories: Hot beverages; milk; fruit and vegetable juices; caloric soft drinks; diet soft drinks; alcoholic drinks; other beverages; and water. Total water intake and water intake from beverages was 3254 (SE 43) mL/day and 2551 (SE 39) mL/day in study A; and 2349 (SE 59) mL/day and 1832 (SE 56) mL/day in study B. In both studies water had the highest contribution to total water intake, approximately 50% of total water intake, followed by hot beverages (10% of total water intake) and milk (5% of total water intake). These two approaches contribute information on water intake in Greece and highlight the contribution of different beverages; moreover, they point out differences in results obtained from different methodologies attributed to limitations in their use.

Longitudinal Assessment of Blood Pressure in School-Aged Children: A 3-Year Follow-Up Study

The purpose of this study was to assess the prevalence of abnormal blood pressure in a population of school children during a 3-year follow-up period and its relationship with obesity. Anthropometric and blood pressure data were collected from a population of Italian school children during three consecutive years. During each year blood pressure measurements were repeated three times, at intervals of 1 week. A total of 564 school-children [311 boys; mean (SD) age 8.8 ± 1.4 years] were recruited. During each year, systolic and diastolic blood pressure decreased from visit 1 to visit 3 (p < 0.001). This was associated with a decline in the percentage of prehypertension/hypertension from visit 1 to visit 3. An abnormal blood pressure value in at least one study visit was found in 8.8-17 % of children, whereas the prevalence of hypertension at all three study visits was between 5.2 and 7.8 %, and that of prehypertension at all three visits was between 2.8 and 3.8 %. High blood pressure was more frequent in obese children. In this population of school children the percentage of prehypertension/hypertension remarkably varied when based on one versus three annual assessments, thus emphasizing the importance of repeated measurement before making a diagnosis of abnormal blood pressure. Adiposity was confirmed to be a determinant of high blood pressure.

A Western dietary pattern is associated with higher blood pressure in Iranian adolescents

PURPOSE

The dietary determinants of adolescent blood pressure (BP) are not well understood. We determined the association between major dietary patterns and BP in a sample of Iranian adolescents.

METHODS

This cross-sectional study was conducted among a representative sample (n = 557) of Shirazi adolescents aged 12-19 years. Participants' systolic and diastolic BP was measured using a validated oscillometric BP monitor. Usual dietary intakes during the past 12 months were assessed using a valid and reproducible 168-item semiquantitative food frequency questionnaire through face-to-face interviews. Principal component factor analysis was used to identify major dietary patterns based on a set of 25 predefined food groups.

RESULTS

Overall, three major dietary patterns were identified, among which only the Western pattern (abundant in soft drinks, sweets and desserts, salt, mayonnaise, tea and coffee, salty snacks, high-fat dairy products, French fries, and red or processed meats) had a significant association with BP. After adjusting for potential confounders in the analysis of covariance models, multivariable adjusted means of the systolic and mean BP of subjects in the highest tertile of the Western pattern score were significantly higher than those in the lowest tertile (for systolic BP: mean difference 6.9 mmHg, P = 0.001; and for mean BP: mean difference 4.2 mmHg, P = 0.003). A similar but statistically insignificant difference was observed in terms of diastolic BP.

CONCLUSIONS

The findings suggest that a Western dietary pattern is associated with higher BP in Iranian adolescents. However, additional large-scale prospective studies with adequate methodological quality are required to confirm these findings.