Blood fatty acid composition in relation to allergy in children aged 2-9 years: results from the European IDEFICS study.

BACKGROUND/OBJECTIVES: Blood polyunsaturated fatty acids (PUFA) are involved in allergy development, but the etiological role of n-6 and n-3 PUFA is still controversial. A European multicenter study of children (IDEFICS) provided the opportunity to explore the cross-sectional association between fatty acids (FA) and allergy. SUBJECTS/METHODS: Blood FA levels were measured in 2600 children aged 2-9 years and were recorded as the percentage of weight of all FA detected. Logistic regression of allergy status on FA components was adjusted for age, sex, country, body mass index, family history of allergic disease, breast-feeding, and number of siblings. The results were given as odds ratios (OR) for current vs no allergy ever and an increase in FA by 1 s.d. RESULTS: Overall, higher proportions of n-6 PUFA were associated with higher odds of allergy (OR=1.21 (1.05, 1.40)). Monounsaturated FA (MUFA) were associated with reduced risk for allergy (OR=0.75 (0.65, 0.87)), whereas saturated FA did not differ by allergy status. The strongest associations were observed in children <4 years old, with ORs of allergy given as 1.62 (1.15, 2.29) for n-3 PUFA and 0.63 (0.42, 0.95) for MUFA. With regard to individual FA, these associations were independently observed for docosapentaenoic acid (22:5 n-3) and oleic acid (18:1 n-9). CONCLUSIONS: Both PUFA subtypes were positively associated with allergy in an age-dependent manner, whereas MUFA was associated with less allergy. The observation of high proportions of n-3 PUFA in allergic children younger than 4 years might help to understand the nature of early onset of atopic disease.

Association of heart rate and blood pressure among European adolescents with usual food consumption: The HELENA study.

BACKGROUND AND AIM: In adults, there is some evidence that improving diet reduces blood pressure (BP) and the subsequent risk of cardiovascular diseases (CVDs). However, studies that analyse this association in adolescents are still scarce. The objective of the present study was to examine the associations between heart rate, systolic (SBP), diastolic (DBP) and mean arterial blood pressure (MAP) among European adolescents and usual intake of vegetables, fruits, dairy products, meat, fish, high-sugar foods and savoury snacks. METHODS AND RESULTS: In total, 2283 adolescents from the HELENA-study (12.5-17.5 years old; 1253 girls) were included. Dietary intake was assessed using two computerized 24-hour dietary recalls. Age, sex, body mass index, maternal educational level, physical activity and Tanner stage were considered as confounders. Associations were examined by mixed model analysis stratified by sex. Tests for trend were assessed by tertiles of intake while controlling for the aforementioned confounders. Dairy products and fish intake were negatively associated with BP and heart rate. Significant decreasing trends were observed for heart rate and BP across tertiles of dairy products, fish intake and high-sugar foods intake (p < 0.05). Significant increasing trends were observed for SBP and MAP across tertiles of savoury snack intake (p < 0.05). CONCLUSION: Significant but small inverse associations between fish and dairy products consumption with blood pressure and heart rate have been found in European adolescents. Dietary intervention studies are needed to explore these associations in the context of the modification of several risk factors for the prevention of cardiovascular diseases.

Does the FTO gene interact with the socioeconomic status on the obesity development among young European children? Results from the IDEFICS study.

BACKGROUND: Various twin studies revealed that the influence of genetic factors on psychological diseases or behaviour is more expressed in socioeconomically advantaged environments. Other studies predominantly show an inverse association between socioeconomic status (SES) and childhood obesity in Western developed countries. The aim of this study is to investigate whether the fat mass and obesity-associated (FTO) gene interacts with the SES on childhood obesity in a subsample (N = 4406) of the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS) cohort. METHODS: A structural equation model (SEM) is applied with the latent constructs obesity, dietary intakes, physical activity and fitness habits, and parental SES to estimate the main effects of the latter three variables and a FTO polymorphism on childhood obesity. Further, a multiple group SEM is used to explore whether an interaction effect exists between the single nucleotide polymorphism rs9939609 within the FTO gene and SES. RESULTS: Significant main effects are shown for physical activity and fitness (standardised [betacrc ](s) = -0.113), SES ([betacrc ](s) = -0.057) and the FTO homozygous AA risk genotype ([betacrc ](s) = -0.177). The explained variance of obesity is ~9%. According to the multiple group approach of SEM, we see an interaction between SES and FTO with respect to their effect on childhood obesity (Δχ(2) = 7.3, df = 2, P = 0.03). CONCLUSION: Children carrying the protective FTO genotype TT seem to be more protected by a favourable social environment regarding the development of obesity than children carrying the AT or AA genotype.

Blood pressure reference values for European non-overweight school children: the IDEFICS study.

OBJECTIVES: To provide oscillometric blood pressure (BP) reference values in European non-overweight school children. DESIGN: Cross-sectional analysis from the IDEFICS study (www.ideficsstudy.eu) database. METHODS: Standardised BP and anthropometric measures were obtained from children aged 2 to 10.9 years, participating in the 2007-2008 and 2009-2010 IDEFICS surveys. Age- and height-specific systolic and diastolic pressure percentiles were calculated by GAMLSS, separately for boys and girls, in both the entire population (n=16,937) and the non-overweight children only (n=13,547). The robustness of the models was tested by sensitivity analyses carried out in both population samples. RESULTS: Percentiles of BP distribution in non-overweight children were provided by age and height strata, separately for boys and girls. Diastolic BP norms were slightly higher in girls than in boys for similar age and height, while systolic BP values tended to be higher in boys starting from age 5 years. Sensitivity analysis, comparing BP distributions obtained in all children with those of non-overweight children, showed that the inclusion of overweight/obese individuals shifted the references values upward, in particular systolic BP in girls at the extreme percentiles. CONCLUSIONS: The present analysis provides updated and timely information about reference values for BP in children aged 2 to <11 years that may be useful for monitoring and planning population strategies for disease prevention.

Blood lipids among young children in Europe: results from the European IDEFICS study.

BACKGROUND: Measurement of cholesterol and triglyceride (TG) fractions in blood has become standard practice in the early detection of atherosclerotic disease pathways. Considerable attention is given nowadays to the presence of these risk factors in children and to start preventive campaigns early in life. In this context, it is imperative to have valid comparative frameworks for interpretation of lipid levels. The aim of this study is to present sex- and age-specific reference values on blood lipid levels in European children aged 2.0-10.9 years. METHODS: Fasting blood was obtained via either venipuncture or capillary sampling. In 13,579 European non-obese children (50.3% boys), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), TG and TC/HDL-C ratio levels were measured with a point-of-care analyser (Cholestech). Sex- and age-specific reference values were computed with the GAMLSS method with the statistical software R. RESULTS: Reference curves and 1st, 3rd, 10th, 25th, 50th, 75th, 90th, 97th and 99th percentile values are presented. HDL-C showed a positive trend with age, from 2 years onwards, but was relatively stable above the age of 7. For LDL-C and TC, linear but small age-related trends were seen. The TC/HDL-C values showed a gradual negative trend from the age of 2 up to 6 and were relatively stable afterwards. For TG, no age trend was found (P=0.285). Boys had higher mean HDL-C values than girls (1.414 vs 1.368 mmol l(-1)), and lower TC, LDL-C, TC/HDL-C and TG values (3.981 vs 4.087 mmol l(-1); 2.297 vs 2.435 mmol l(-1); 2.84 vs 3.01mmol l(-1); and 0.509 vs 0.542 mmol l(-1), respectively). CONCLUSIONS: These new and recent references could serve as a European orientation of blood lipid values in children in the context of standard medical practice and for the purpose of public health screening.

Reference values of whole-blood fatty acids by age and sex from European children aged 3-8 years.

OBJECTIVES: To establish reference values for fatty acids (FA) especially for n-3 and n-6 long-chain polyunsaturated FAs (LC PUFA) in whole-blood samples from apparently healthy 3-8-year-old European children. The whole-blood FA composition was analysed and the age- and sex-specific distribution of FA was determined. DESIGN AND SUBJECTS: Blood samples for FA analysis were taken from 2661 children of the IDEFICS (identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study cohort. Children with obesity (n=454) and other diseases that are known to alter the FA composition (n=450) were excluded leaving 1653 participants in the reference population. MEASUREMENTS: The FA composition of whole blood was analysed from blood drops by a rapid, validated gas chromatographic method. RESULTS: Pearson correlation coefficients showed an age-dependent increase of C18:2n-6 and a decrease of C18:1n-9 in a subsample of normal weight boys and girls. Other significant correlations with age were weak and only seen either in boys or in girls, whereas most of the FA did not show any age dependence. For age-dependent n-3 and n-6 PUFA as well as for other FA that are correlated with age (16:0, C18:0 and C18:1n-9) percentiles analysed with the general additive model for location scale and shape are presented. A higher median in boys than in girls was observed for C20:3n-6, C20:4n-6 and C22:4n-6. CONCLUSIONS: Given the reported associations between FA status and health-related outcome, the provision of FA reference ranges may be useful for the interpretation of the FA status of children in epidemiological and clinical studies.

The role of dietary fat on the association between dietary amino acids and serum lipid profile in European adolescents participating in the HELENA Study.

BACKGROUND/OBJECTIVES: The objective of this study was to examine the relationship between amino acid (AA) intake and serum lipid profile in European adolescents from eight European cities participating in the cross-sectional (2006-2007) HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study, and to assess whether this association was independent of total fat intake. SUBJECTS/METHODS: Diet, skinfold thickness, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), TC/HDL-c ratio, low-density lipoprotein cholesterol (LDL-c), apolipoprotein B (Apo B), apolipoprotein A1 (Apo A1) and Apo B/Apo A1 ratio were measured in 454 12.5- to 17.5-year-old adolescents (44% boys). Intake was assessed via two non-consecutive 24-h dietary recalls. Data on maternal education and sedentary behaviors were obtained via questionnaires. Physical activity was objectively measured by accelerometry. RESULTS: Alanine, arginine, asparaginic acid, glycine, histidine, lysine and serine intakes were inversely associated with serum TG concentrations in both boys and girls. Intake of other AA like alanine and/or arginine was also inversely associated with serum TC, LDL-c and Apo B/Apo A1 ratio only in girls. An inverse association was observed between intakes of alanine, isoleucine, leucine, methionine, serine, tryptophan, tyrosine and valine and TC/HDL-c ratio among female adolescents. Similar results were found in males for serine and tryptophan intakes. It is noteworthy, however, that associations were no longer significant in both genders when total fat intake was considered as a confounding factor. CONCLUSIONS: In this sample of adolescents, the association between AA intakes and serum lipid profile did not persist when dietary fat was considered. Therefore, dietary interventions and health promotion activities should focus on fat intake to improve lipid profile and potentially prevent cardiovascular disease.

Evaluation of food and nutrient intake assessment using concentration biomarkers in European adolescents from the Healthy Lifestyle in Europe by Nutrition in Adolescence study.

Accurate food and nutrient intake assessment is essential for investigating diet-disease relationships. In the present study, food and nutrient intake assessment among European adolescents using 24 h recalls (mean of two recalls) and a FFQ (separately and the combination of both) were evaluated using concentration biomarkers. Biomarkers included were vitamin C, ß-carotene, DHA+EPA, vitamin B12 (cobalamin and holo-transcobalamin) and folate (erythrocyte folate and plasma folate). For the evaluation of the food intake assessment 390 adolescents were included, while 697 were included for the nutrient intake assessment evaluation. Spearman rank and Pearson correlations, and validity coefficients, which are correlations between intake estimated and habitual true intake, were calculated. Correlations were higher between frequency of food consumption (from the FFQ) and concentration biomarkers than between mean food intake (from the recalls) and concentration biomarkers, especially for DHA+EPA (r 0·35 v. r 0·27). Most correlations were higher among girls than boys. For boys, the highest validity coefficients were found for frequency of fruit consumption (0·88) and for DHA+EPA biomarker (0·71). In girls, the highest validity coefficients were found for fruit consumption frequency (0·76), vegetable consumption frequency (0·74), mean fruit intake (0·90) and DHA+EPA biomarker (0·69). After exclusion of underreporters, correlations slightly improved. Correlations between usual food intakes, adjusted for food consumption frequency, and concentration biomarkers were higher than correlations between mean food intakes and concentration biomarkers. In conclusion, two non-consecutive 24 h recalls in combination with a FFQ seem to be appropriate to rank subjects according to their usual food intake.

The relationship between paediatric calcaneal quantitative ultrasound measurements and dual energy X-ray absorptiometry (DXA) and DXA with laser (DXL) as well as body composition.

BACKGROUND: Quantitative ultrasound (QUS) is a quick, non-invasive and inexpensive method to measure bone strength. Moreover, the device is portable, which makes it easy to be used in the field. In contrast to other bone measuring techniques, QUS does not use any ionised radiation. However, the validity of QUS in the measurement of bone health and the relationship between QUS output and body composition have not been assessed in very young children. OBJECTIVE: To investigate the relationship between paediatric calcaneal QUS and both dual-energy X-ray absorptiometry (DXA) and calcaneal DXA with laser (DXL) and body composition parameters. SUBJECTS: A total of 37 Belgian children (10 boys and 27 girls; 4 to 8 years old) underwent a calcaneal QUS as well as a DXA scan. A total of 24 Swedish children (15 boys and 9 girls; 3 to 5 years old) underwent a calcaneal QUS as well as a heel DXL scan. The height and weight of all children were measured. RESULTS: The QUS stiffness index (SI) was significantly negatively correlated with bone mineral density (BMD) of the total body (r=-0.370, P=0.02). No significant correlations were found between the SI and DXL results. In the total sample, the SI showed a significant positive correlation with body mass index (BMI) (r=0.298, P=0.02), even after correction for age, gender and centre. In the Belgian sample, the SI was also significantly positively correlated with total body fat mass content (r=0.416, P=0.01) and body fat percentage (r=0.566, P<0.01) obtained by whole-body DXA. CONCLUSION: The SI measured by QUS does not correlate significantly with BMD values measured by DXA or DXL in 3- to 8-year-old children. However, there is a significant positive correlation between SI and BMI and body fat %.