Environmental impact of the diet of young Portuguese and its relationship with adherence to the Mediterranean Diet.

OBJECTIVE: To estimate, in a cohort of young Portuguese adults, the environmental impact (greenhouse gas (GHG) emissions, land use, energy used, acidification and potential eutrophication) of diet according to adherence to the Mediterranean Diet (MD). METHODS: Data from 1554 participants of the Epidemiologic Health Investigation of Teenagers in Porto (EPITeen) were analysed. Food intake and MD adherence were determined using validated questionnaires. The environmental impact was evaluated with the EAT-Lancet Commission tables, and the link between MD adherence and environmental impact was calculated using adjusted multivariate linear regression models. RESULTS: Higher adherence (high vs. low) to the MD was associated with lower environmental impact in terms of land use (7.8 vs. 8.5 m2, p = 0.002), potential acidification (57.8 vs. 62.4 g SO2-eq, p = 0.001) and eutrophication (21.7 vs. 23.5 g PO4-eq, p < 0.001). Energy use decreased only in the calorie-adjusted model (9689.5 vs. 10,265.9 kJ, p < 0.001), and GHG emissions were reduced only in a complementary model where fish consumption was eliminated (3035.3 vs. 3281.2 g CO2-eq, p < 0.001). Meat products had the greatest environmental impact for all five environmental factors analysed: 35.7% in GHG emissions, 60.9% in energy use, 72.8% in land use, 70% in acidification and 61.8% in eutrophication. CONCLUSIONS: Higher adherence to the MD is associated with lower environmental impact, particularly in terms of acidification, eutrophication, and land use. Reducing meat consumption can contribute to greater environmental sustainability.

Early life exposures are associated with appetitive traits in infancy: findings from the BiTwin cohort.

PURPOSE: To determine the stability of appetitive traits during infancy and their association with early life exposures. METHODS: Participants were from the BiTwin birth cohort (longitudinal study of Portuguese infants). Appetitive traits at 3 months were measured using the Baby Eating Behaviour Questionnaire (n = 347) and at 12 months with the Children's Eating Behaviour Questionnaire for toddlers (n = 325). Stability was assessed with multi-level models. The association of early life exposures (weight for gestational age, mode of feeding, prematurity, smoking during pregnancy, maternal pre-pregnancy BMI, gestational weight gain, and diabetes mellitus diagnosis) with infant appetitive traits was estimated by multivariable linear regression models. RESULTS: Appetite traits showed limited stability (ICCs: 0.25-0.34). Associations with early life exposures varied by age. At 3 months, infants of mothers with higher pre-pregnancy BMI and excessive gestational weight gain had low Satiety Responsiveness. In contrast, infants small for gestational age scored high in this trait (ß̂ = 0.241; 95% CI 0.056-0.425). Exclusively formula-fed infants presented weak food approach traits at this age, namely low Enjoyment of Food (ß̂ = - 0.145; 95% CI - 0.270 to - 0.019) and Food Responsiveness (ß̂ = - 0.415; 95% CI - 0.618 to - 0.212). At 12 months, infants who were small for gestational age had low Food Responsiveness (ß̂ = - 0.297; 95% CI - 0.523 to - 0.072), in contrast, infants of mothers who gained excessive gestational weight had high scores in this trait. Formula feeding was related to rapid eating (Slowness in Eating: ß̂ = - 0.252; 95% CI 0.451 to - 0.054). CONCLUSION: Early life exposures may play a role in the development of infants' appetitive traits, which then change during the first year of life. Interventions focussed on maternal and infant health may have the potential to shape appetite in infancy.

MULT: New height references and their efficiency in multi-ethnic populations.

OBJECTIVES: To develop new height references (MULT) based on longitudinal data of multi-ethnic populations and to compare them to the height references from the Dutch Growth Study, from the Centers for Disease Control and Prevention (CDC) and from the World Health Organization (WHO). METHODS: The MUL height references were developed through the LMS method and the Generalized Additive Models for Location Scale and Shape. They were constructed based on 2611 subjects (15 292 measurements) from the advantaged quintile of the Young Lives (Younger Cohort), Millennium Cohort Study, Adolescent Nutritional Assessment Longitudinal Study, and Epidemiological Health Investigation of Teenagers in Porto studies. The M, S curves were described to compare the growth trajectory of the MULT, DUTCH, CDC and WHO height references. For the population comparative analysis, we used the total sample of the studies (91 063 observations, 17 641 subjects). The Lin's concordance correlation coefficient (CCC) and Cohen's kappa coefficient (K) were used to verify the agreement between MULT, WHO and CDC height references. RESULTS: The MULT height references showed taller boys for the periods of 61-174 months and 196-240 months and taller girls for 61-147 and 181-240 months, when compared to CDC and WHO height references. There was an almost perfect agreement between WHO and MULT height references (CCC >0.99) for the subjects aged 2 to 5 years. CONCLUSIONS: MULT height references presented a taller population and a high agreement with WHO growth charts, especially for children under 5 years, indicating that it could be useful to assess nutritional status of multi-ethnic populations.

The emergence of socioeconomic inequalities in smoking during adolescence and early adulthood.

BACKGROUND: While it is known that educational inequalities in smoking start during early and middle adolescence, it is unknown how they further develop until adulthood. The aim of this article is to map, in the Portuguese context, how educational inequalities in smoking emerge from pre-adolescence until young adulthood. METHODS: This study used longitudinal data from the EPITeen Cohort, which recruited adolescents enrolled in schools in Porto, Portugal. We included the 1,038 participants followed at ages 13 (2003/2004), 17, 21, and 24 years. We computed the odds ratio (OR) for the prevalence of smoking states (never smoking, experimenter, less-than-daily, daily and former smoker) and the incidence of transitions between these states, as function of age and education, stratified by sex. We also added interaction terms between age and education. RESULTS: Educational inequalities in daily smoking prevalence, with higher prevalence among those with lower educational level, emerged at 17 years old and persisted until higher ages. They were formed in a cumulative way by the increased risk of experimenting between 13 and 17 years, and increased risk of becoming daily smoker between 17 and 21 years. The incidence of smoking cessation was higher among the higher educated. Inequalities were formed similarly for women and men, but with lower level and showed no significance among women. CONCLUSIONS: These results highlight that actions to prevent smoking should also take in account the potential impact in smoking inequalities, and should focus not only on middle adolescence but also on late adolescence and early adulthood.

Socioeconomic factors and intergenerational differences in height of Portuguese adults born in 1990: results from the EPITeen cohort.

Average adult height is an indicator of population health and a marker of socioeconomic inequalities. This study aimed to assess how socioeconomic differences affect intergenerational height increase between adults born in 1990 and their parents. Data from a population-based cohort of subjects born in 1990 (EPITeen) were analysed. Participants' adult height was objectively measured. Parental height, education, and occupation were reported by the parents. The height difference between daughters and their mothers (n=707), and sons and their fathers (n=647) was calculated. A generalised linear model was used to assess the association between parental education and occupation, separately, and the intergenerational height difference, adjusted for maternal age at birth, smoking during pregnancy, birthweight adjusted for gestational age, and birth order. Females were on average 1.46cm (SD=6.62) taller than their mothers, and males 3.00cm (SD=7.26) taller than their fathers. The highest height gain was shown in those with less advantaged socioeconomic background. In the adjusted model, sons whose mothers had 0-6 years of education grew 3.9cm taller (ß=3.894; 95%CI:2.345;5.443) and daughters 1.5cm taller (ß=1.529; 95%CI:0.180;2.878) (compared to >12y maternal education); for paternal education, sons and daughters grew 3.5cm (ß=3.480; 95%CI:1.913;5.047) and 1.9cm taller (ß=1.895; 95%CI:0.526;3.265), respectively. A higher height increase was found in participants with less advantaged maternal and paternal occupational level. Adults born in 1990 are taller than their parents, and height gain was higher in males than females. Adults from a lower socioeconomic status experienced the highest height gain, suggesting a reduction in height inequality.

Consumption of ultra-processed foods and IL-6 in two cohorts from high- and middle-income countries.

This study evaluated the association between ultra-processed foods (UPF) on serum IL-6 and to investigate the mediation role of adiposity. Participants were 524 adults from the EPITeen Cohort (Porto, Portugal) and 2888 participants from the 1982 Pelotas Birth Cohort (Pelotas, Brazil). Dietary intake was collected using FFQ when participants were 21 years of age in the EPITeen and 23 years in the Pelotas Cohort. Serum IL-6 and body fat mass were evaluated when participants were 27 and 30 years old in the EPITeen and Pelotas, respectively. Generalised linear models were fitted to test main associations. Mediation of body fat mass was estimated using G-computation. After adjustment for socio-economic and behaviour variables, among females from the EPITeen, the concentration of IL-6 (pg/ml) increased with increasing intake of UPF from 1·31 (95 % CI 0·95, 1·82) in the first UPF quartile to 2·20 (95 % CI 1·60, 3·01) and 2·64 (95 % CI 1·89, 3·69) for the third and fourth UPF quartiles, respectively. A similar result was found among males in the Pelotas Cohort, IL-6 increased from 1·40 (95 % CI 1·32, 1·49) in the first UPF quartile to 1·50 (95 % CI 1·41, 1·59) and 1·59 (95 % CI 1·49, 1·70) in the two highest UPF quartiles. The P-value for the linear trend was < 0·01 in both findings. The indirect effect through fat mass was NS. Our findings suggest that the consumption of UPF was associated with an increase in IL-6 concentration; however, this association was not explained by adiposity.

Dietary glycemic load and its association with glucose metabolism and lipid profile in young adults.

BACKGROUND AND AIM: To evaluate the association of Glycemic Load (GL) with glucose metabolism and blood lipids among young adults. METHODS AND RESULTS: This study included 1538 participants (51% females), evaluated at 21 years of age as part of the EPITeen cohort. The GL of each individual was obtained from the assessment of their dietary intake by using a 86-item semi-quantitative food frequency questionnaire. The evaluation included anthropometric measurements and a fasting blood sample was used to measure glucose, insulin, triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Insulin resistance was calculated based on the homeostasis model method (HOMA-IR). The association between the GL and the biochemical parameters was evaluated by linear regression models using ß and 95% confidence intervals (95% CI), stratified by sex and adjusted for body mass index (BMI), energy and fiber intake, and self-perceived social class. No association was found between GL and the glucose metabolism parameters after adjustment. Regarding blood lipids, a positive association was found with LDL-C (ß = 1.507, 95% CI 0.454; 2.561 for females; ß = 0.216, 95% CI -0.587; 1.020 for males) and a negative association with HDL-C (ß = -0.647, 95% CI -1.112; -0.181 for females; ß = -0.131, 95% CI -0.422; 0.160 for males). CONCLUSIONS: Our results suggest that, in healthy young subjects, a high GL diet may have a negative impact on lipid profile.

Socioeconomic circumstances and lung function growth from early adolescence to early adulthood.

BACKGROUND: A reduced lung function in early adulthood is associated with respiratory and non-respiratory diseases and is a long-term predictor of mortality. This study investigated the association between early socioeconomic circumstances (SEC) and lung function growth trajectories from early adolescence until early adulthood. METHODS: We analysed data from the EPITeen population-based study, including adolescents born in 1990. Study waves occurred at 13, 17 and 21 years of age. Information on sociodemographic, behavioural and health factors, anthropometry and spirometry was collected. Early-life SEC were assessed using maternal education and paternal occupational position. The forced expiratory volume in the first second (FEV1) growth trajectories were drawn considering sex-and-height interactions over an 8-year period. Our sample included 2022 participants with complete information for the relevant variables. RESULTS: Participants from most disadvantaged SEC presented lower FEV1 at early adolescence compared to high-SEC counterparts, but differences seem to diminish with height growth. The effect of paternal occupational position in lung function growth trajectories was moderated by height, thus individuals from fathers with less advantaged occupational position had lower FEV1 at early adolescence, but they had a faster FEV1 growth over time. CONCLUSIONS: Individuals from most disadvantaged SEC presented lower lung function at early adolescence compared to high-SEC counterparts; nevertheless, a catch-up growth was observed. IMPACT: Lower socioeconomic circumstances were previously associated with reduced lung function and a higher risk of respiratory diseases in adults. Fewer studies analysed the effects of early-life socioeconomic circumstances in lung function growth during adolescence. Disadvantaged socioeconomic circumstances were associated with lower lung function in early adolescence. However, social differences diminished over adolescence, suggesting a catch-up growth of lung function among those from lower socioeconomic circumstances. An improved understanding of the mechanism underlying lung function catch-up (or the absence of catch-up) might support interventions to narrow social inequalities in respiratory health and should be further investigated.

Indoor environmental quality in households of families with infant twins under 1 year of age living in Porto.

Exposure to air pollution in early years can exacerbate the risk of noncommunicable diseases throughout childhood and the entire life course. This study aimed to assess temperature, relative humidity (RH), carbon dioxide (CO2) and monoxide (CO), particulate matter (PM2.5, PM10), ultrafine particles, nitrogen dioxide (NO2), ozone (O3), formaldehyde, acetaldehyde and volatile organic compounds (VOC) levels in the two rooms where infant twins spend more time at home (30 dwellings, Northern Portugal). Findings showed that, in general, the worst indoor environmental quality (IEQ) settings were found in bedrooms. In fact, although most of the bedrooms surveyed presented adequate comfort conditions in terms of temperature and RH, several children are sleeping in a bedroom with improper ventilation and/or with a significant degree of air pollution. In particular, mean concentrations higher than recommended limits were found for CO2, PM2.5, PM10 and total VOC. Additionally, terpenes and decamethylcyclopentasiloxane were identified as main components of emissions from indoor sources. Overall, findings revealed that factors related to behaviors of the occupants, namely related to a conscientious use of cleaning products, tobacco and other consumer products (air-fresheners, incenses/candles and insecticides) and promotion of ventilation are essential for the improvement of air quality in households and for the promotion of children's health.

Metabolically healthy overweight in young adulthood: is it a matter of duration and degree of overweight?

BACKGROUND AND AIM: Given the controversy regarding metabolically healthy obesity, we studied the association between duration and degree of body mass index (BMI) from adolescence to early adulthood and metabolic status of both overweight/obese and under/normal weight subjects. METHODS AND RESULTS: Participants of the EPITeen cohort were evaluated at 13, 17, 21 and 24 years (n = 1040). Duration and degree of BMI in the 11-year period was summarized through the area under the curve of BMI (BMIAUC). Metabolic health at 24 y was defined as optimal levels of lipids, blood pressure and glucose. The association between BMIAUC per year and metabolic health was estimated through binary logistic regression models, adjusted for confounders and stratified by BMI. The proportion of metabolically healthy overweight/obesity at 24 y was 13.4%. After adjustment for sociodemographic and behavioural factors, the increase of one kg/m2 in BMI on average per year during the period between 13 and 24 y was associated with 14% lower odds of being metabolically healthy among under/normal weight participants (OR = 0.86, 95% CI 0.78-0.94); and 8% lower odds of metabolic health among obese/overweight participants (OR = 0.92, 95% CI 0.85-1.00). After additional adjustment for waist circumference, the association was attenuated, especially in the obese/overweight group (OR = 1.03, 95% CI 0.93-1.14). About 20% of the metabolically healthy obese/overweight at 13 y transitioned to metabolically unhealthy obesity/overweight at 24 y. CONCLUSION: The results support the hypothesis that the healthy obesity phenotype could be explained by a lower exposure to adiposity, either by shorter time or lower quantity, and a more favourable body fat distribution.

Energy intake misreport: how different methods affect its prevalence and nutrient intake estimates.

BACKGROUND: Although different methods for the evaluation of energy intake (EI) misreport have been described, it is unclear which one is the most appropriate. AIM: To assess the performance of these methods in the prevalence of EI misreports and accuracy of nutrient intake estimates. METHODS: Reports of 3,639 adults from the Portuguese National Food, Nutrition and Physical Activity Survey 2015-2016 were classified using univariate (Willett; interquartile range) and multivariate (Goldberg; predicted total energy expenditure [pTEE], testing different standard deviations [SD]) methods. Self-reported intakes were compared to their respective estimates by urinary excretion in a sub-sample of 80. The effect of the exclusion of misreporters on nutrient estimates was assessed by the differences in linear regression coefficients between plausible and total sample. RESULTS: The highest prevalence of EI misreport was observed using pTEE 1SD (63.9%). Differences in the associations between nutrient self-reported intake and estimated intake using urinary biomarkers were verified with misreporters' exclusion by pTEE 1SD method (ß-protein = 0.209; 95% CI = 0.074-0.529; ß-potassium = 0.276; 95% CI = 0.060-0.560) and Goldberg 2SD (ß-protein = 0.080; 95% CI = 0.025-0.235; ß-potassium = 0.106; 95% CI = -0.048-0.246). CONCLUSIONS: Multivariate methods lead to a higher prevalence of misreports and larger differences in nutrient estimates. The application of the pTEE 1SD and Goldberg 2SD methods resulted in more accurate nutrient estimates.

Assessment of indoor air conditions in households of Portuguese families with newborn children. Implementation of the HEALS IAQ checklist.

Conducting epidemiological and risk assessment research that considers the exposome concept, as in the case of HEALS project, requires the acquisition of higher dimension data sets of an increased complexity. In this context, new methods that provide accurate and interpretable data summary on relevant environmental factors are of major importance. In this work, a questionnaire was developed to collect harmonized data on potential pollutant sources to air in the indoor environment where children spend an important part of their early life. The questionnaire was designed in a user friendly checklist format to be filled out at the maternity in ten European cities. This paper presents and discusses the rationale for the selection of the questionnaire contents and the results obtained from its application in the households of 309 HEALS-enrolled families with babies recently born in Porto, Portugal. The tool was very effective in providing data on the putative air pollution sources in homes, with special focus on the bedroom of the newborns. The data collected is part of a wider effort to build the databases and risk assessment models of the HEALS project. The results of the analysis of the collected data suggest that, for the population under study, the main concerns on early life exposures at home can be related to emissions from the use of household solid fuels, indoor tobacco, household cleaning products, fragranced consumer products (e.g. air fresheners, incense and candles), moisture-related pathologies and traffic-related outdoor pollution. Furthermore, it is anticipated that the tool can be a valuable means to empower citizens to actively participate in the control of their own exposures at home. Within this context, the application of the checklist will also allow local stakeholders to identify buildings presenting most evident IAQ problems for sampling or intervention as well as to guide them in preparing evidence-based educational/awareness campaigns to promote public health through creating healthy households.

Characterizing energy intake misreporting and its effects on intake estimations, in the Portuguese adult population.

OBJECTIVE: The aim of the current study was to evaluate energy intake misreporting prevalence, its associated factors and its effects on nutrient intake, in the Portuguese population aged from 18 to 84 years. DESIGN: Cross-sectional study. SETTING: Portugal. SUBJECTS: Adults participants from the National Food, Nutrition and Physical Activity Survey, IAN-AF, 2015-2016, who provided two complete 24 h dietary recall and complete covariate information. RESULTS: Under, plausible and over-reporters were identified according to the Goldberg method. Total misreporting prevalence was 29·9 %, being 28·5 % of under-reporting and 1·4 % of over-reporting. The current study found higher odds of being classified as an under-reporter especially in participants with higher BMI and in those who self-reported health perception status as non-favourable. Energy intake estimation increases by 853.5 kJ/d (204 kcal/d) when misreporters are excluded, and the same tendency is observed for macro and micronutrients. It is worth mentioning that the prevalence of inadequacy for protein intake decreases by about 5 % when considering plausible reporters. CONCLUSIONS: The exclusion of misreporters has a small impact on the crude energy and nutrient estimates as well as on assessing the contribution of nutrients to total energy intake. However, a moderate impact was observed in the estimation of nutrient inadequacy prevalence.

Total, added and free sugar intakes, dietary sources and determinants of consumption in Portugal: the National Food, Nutrition and Physical Activity Survey (IAN-AF 2015-2016).

OBJECTIVE: To assess total sugar (TS), added sugar (AS) and free sugar (FS) intakes, dietary sources, adherence to recommendations and determinants of consumption, in a Portuguese national sample. DESIGN: Cross-sectional study. Dietary assessment was obtained by two food diaries in children aged <10 years and two non-consecutive 24 h recalls for other age groups. TS, AS and FS intakes were estimated by using SPADE software. TS content in food was estimated at the ingredient level. AS content in food was assessed through a systematic methodology and FS was based on the WHO definition. SETTING: National Food, Nutrition and Physical Activity Survey (IAN-AF 2015-2016), Portugal. PARTICIPANTS: Representative sample from the Portuguese population, aged from 3 months to 84 years (n 5811). RESULTS: Mean daily intake and contribution to total energy intake (E%) were 84·3 g/d (18·5 E%) for TS, 32·1 g/d (6·8 E%) for AS and 35·3 g/d (7·5 E%) for FS. Of the population, 76 % adhered to the FS recommendation (FS < 10 E%). The lowest adherence was in children (51·6 %) and adolescents (51·3 %). The main dietary source of TS was fruit across all ages, except in adolescents which was soft drinks. In children, the main dietary sources of FS were yoghurts and sweets, soft drinks in adolescents and table sugar in adults/elderly. FS intake was lower in children with more educated parents and in adults who practised physical activity regularly, and higher among smokers. CONCLUSIONS: Interventions ought to be planned towards decreasing intakes of added and free sugars considering population-specific characteristics.

Parental education associated with immune function in adolescence.

BACKGROUND: The immune system is affected and shaped by several internal and external factors. Among the external variables, the socioeconomic status is known to influence the immune system since the early years of life and throughout life. METHODS: In this study, we assessed the relationship between parental education with the white blood cells and its subtypes in 1213 adolescents from the EPITeen cohort, assessed at the age of 13. Beta coefficients (ß) and 95% confidence intervals (CI) were fitted using linear regression models to quantify the association and were adjusted for sex, body mass index and chronic disease. RESULTS: After adjustment, parental education presented a negative association with white blood cells, which was significant among those with higher high-sensitivity C-reactive protein (hs-CRP) median levels [-0.05 mg/l (95% CI -0.08, -0.01)]. On the contrary, a positive association with lymphocytes was observed, which was, significant among those with lower hs-CRP [0.17 mg/l (95% CI 0.02, 0.32)]. A neutrophil-to-lymphocyte ratio significant decrease was also observed with the increment of parental education (P<0.001). CONCLUSION: We found that parental education was positively associated with a higher proportion of lymphocytes and a lower proportion of neutrophils, suggesting that parental education is associated with offsprinǵs innate immune system regulation. These results may contribute to clarify the relationships between childhood socioeconomic status and increased risk of adverse cardiovascular outcomes and other immune-related diseases.

The NAD+-dependent deacetylase SIRT2 attenuates oxidative stress and mitochondrial dysfunction and improves insulin sensitivity in hepatocytes.

Insulin resistance is a major predictor of the development of metabolic disorders. Sirtuins (SIRTs) have emerged as potential targets that can be manipulated to counteract age-related diseases, including type 2 diabetes. SIRT2 has been recently shown to exert important metabolic effects, but whether SIRT2 regulates insulin sensitivity in hepatocytes is currently unknown. The aim of this study is to investigate this possibility and to elucidate underlying molecular mechanisms. Here, we show that SIRT2 is downregulated in insulin-resistant hepatocytes and livers, and this was accompanied by increased generation of reactive oxygen species, activation of stress-sensitive ERK1/2 kinase, and mitochondrial dysfunction. Conversely, SIRT2 overexpression in insulin-resistant hepatocytes improved insulin sensitivity, mitigated reactive oxygen species production and ameliorated mitochondrial dysfunction. Further analysis revealed a reestablishment of mitochondrial morphology, with a higher number of elongated mitochondria rather than fragmented mitochondria instigated by insulin resistance. Mechanistically, SIRT2 was able to increase fusion-related protein Mfn2 and decrease mitochondrial-associated Drp1. SIRT2 also attenuated the downregulation of TFAM, a key mtDNA-associated protein, contributing to the increase in mitochondrial mass. Importantly, we found that SIRT2 expression in PBMCs of human subjects was negatively correlated with obesity and insulin resistance. These results suggest a novel function for hepatic SIRT2 in the regulation of insulin sensitivity and raise the possibility that SIRT2 activators may offer novel opportunities for preventing or treating insulin resistance and type 2 diabetes.

Association between insulin resistance and haematological parameters: A cohort study from adolescence to adulthood.

BACKGROUND: The aim of this study was to quantify the relationship between insulin resistance and haematological parameters from adolescence to adulthood. METHODS: Participants from the EPITeen cohort were evaluated at 13, 17, and 21 years, through standardized procedures. A fasting blood sample was obtained, and insulin resistance was evaluated by the homeostatic model assessment (HOMA-IR). The cross-sectional association between HOMA-IR and haematological parameters at 21 years was quantified in 1671 participants by multivariate linear regression coefficients (ß) and 95% confidence intervals (95%CI). For the longitudinal analysis (n = 496), trajectories of insulin and glucose were estimated using model-based clustering, and haematological parameters were compared according to trajectories using ANOVA. RESULTS: At 21 years, after adjustment for BMI, positive associations (ß [95%CI]) were found between HOMA-IR and red blood count (0.05 [0.03;0.07] in females; 0.02 [0.00;0.04] in males); and haematocrit (0.29 [0.12;0.46] in females; 0.21 [0.04,0.38] in males). In females, HOMA-IR was inversely associated with packed cell volume (PCV) (-0.35 [-0.66;-0.05]) and iron levels (-3.98 [-6.94,-1.03]) but positively associated with white blood cells (0.31 [0.19;0.43]) and platelets (7.66 [3.93;11.39]). In males, a higher HOMA-IR was significantly associated with higher haemoglobin (0.09 [0.03;0.16]). Regarding the longitudinal analysis, similar trends were found, but statistical significance was not reached. CONCLUSIONS: Both longitudinal and cross-sectional analyses support the hypothesis that insulin resistance is associated with increased red blood cells count and haematocrit in young adults, even within normal ranges of insulin and glucose.

The use of weight adjusted for height rather than body mass index to assess growth trajectory: Results from a population-based cohort.

We compared different growth models parameterizations regarding (i) adjustment of weight-for-height, as denoted by body mass index (BMI); (ii) adjustment for different covariates, ie, age or height; and (iii) the use of different smoothing methods, ie, polynomial, fractional polynomial, or linear splines. A total of 11 459 measurements of weight and height from 719 participants were used, obtained from the EPITeen cohort at 13, 17, and 21 years, and extracted from child health books. The individual growth curves were modeled using mixed-effects polynomial, fractional polynomial, and linear splines, and each model parameterization included as covariate age or height. The goodness-of-fit of the model parametrizations was compared using the relative squared error (RSE) and the relative absolute error (RAE). The adjustment of weight-for-height as denoted by BMI was found to be biased, especially for extreme values of height and presented the worst fit indexes from all model parameterizations tested (RSE = 12.46%; RAE = 22.63%). Regardless of the smoothing method, the weight-for-height retrieved the best fit indexes in comparison to the adjustment for age. With regard to the smoothing methods and comparing weight-for-height model parameterizations, the fractional polynomial model performed better (RSE = 0.75%; RAE = 5.70%), followed by linear splines (RSE = 0.77%; RAE = 5.82%), and conventional polynomial (RSE = 0.91%; RAE = 6.82%). Therefore, growth modeling in pediatric age should be based on the modeling of weight-for-height because the use of BMI leaves residual confounding for height. Regarding the smoothing methods, although differences were relatively small, the fractional polynomials performed better in comparison to conventional polynomials and linear splines.

Decreases in adiposity reduce the risk of hypertension: Results from a prospective cohort of adolescents.

This study aimed to evaluate the effect of age-related changes in body mass index and waist circumference during adolescence on blood pressure levels and incidence of hypertension. Among the 2159 adolescents recruited at 13 years in Porto, Portugal, we evaluated those free of hypertension at baseline and followed-up at 17 years (n = 1377) - EPITeen cohort, 2003-2008. Changes in BMI percentage (BMI%) and waist circumference percentage (WC%) were evaluated continuously as the difference between 13 and 17 years, then categorized in sex-specific quartiles. Hypertension was defined as systolic and/or diastolic blood pressure ≥ 95th sex- age- and height-specific reference percentile. The association between changes in adiposity and incidence of hypertension was computed through generalized linear models with log link function and Poisson distribution [incidence rate ratios (IRR), 95% confidence intervals (95%CI)], adjusting for baseline adiposity, sex, and family history of hypertension. Overall incidence rate of hypertension was 23.8 (95%CI 19.6-28.8) per 1000 person-years. Participants presenting the highest decrease in BMI% from 13 to 17 years (1st quartile) presented lower SBP at 17y, while for those with increasing BMI% (4th quartile) SBP increased. In comparison to stable BMI% (3rd quartile), decreases in BMI% (1st quartile) were associated with 44% lower risk of hypertension at 17y (IRR = 0.56, 95%CI 0.32-0.97). Increases in BMI% (4th quartile) were associated with increased incidence, although without statistical significance (IRR = 1.11, 95%CI 0.66-1.85). Results were similar when considering changes in WC%. Decreases in BMI and WC throughout adolescence in the whole spectrum of adiposity levels presented potential benefit for blood pressure.

Association between the exposure to phthalates and adiposity: A meta-analysis in children and adults.

BACKGROUND: Exposure to environmental chemicals has become one of the major concerns in the past decades. Phthalates are a family of synthetic organic chemicals used in the manufacture of plastics, solvents, and personal care products. These compounds are considered as endocrine-disrupting compounds (EDCs) since they may interfere with the endocrine system and disrupt its physiologic function. AIM: The purpose of this work is to synthesize results from published literature on the association between the exposure to phthalates and adiposity in adults and children. METHODS: We searched PubMed from inception up to 01 August 2019, to retrieve original papers reporting data on the association between EDCs and adiposity, using the following search expression: (("Endocrine disruptor" OR Endocrine disruptor[mh] OR phthalate) AND (Obesity OR Overweight OR BMI OR "Body fat" OR Adipose tissue[mh] OR Body size[mh] OR "body size" OR "body weight" OR Anthropometry OR "anthropometric measures")) AND (humans[mh]). The study variables and characteristics were collected during data extraction, namely the study design, sample, exposure, outcome, descriptive and association measures. Study quality was assessed using the STROBE template for observational studies. Although studies examined several adiposity measures, Body Mass Index (BMI) and Waist Circumference (WC) were the most commonly used, therefore, we used the beta coefficients regarding BMI and WC, and odds ratios when BMI outcome was categorical to perform the meta-analysis. Data from the studies were combined using fixed effects meta-analyses to compute summary regression coefficients or odds ratios and corresponding 95% confidence intervals (95% CI). Heterogeneity between studies was assessed by the I2 statistic. RESULTS: In the systematic review we found 29 publications addressing the association between phthalate compounds and adiposity. The vast majority of the included studies reported associations that were not statistically significant. For most of the phthalate compounds there were few studies providing compatible measures and therefore it was not possible to combine the results in a meta-analysis. Both for BMI and WC, the meta-analysis for MiBP, MCPP and MbzP showed negative associations and null association for MBP in children, although none of them was significant. For MEP, positive but not significant associations were found both in children and adults. Conversely, for MEHP a negative association was found also in children and adults although it did not reach statistical significance. Only for MECPP a significant association was found for obesity in adults (OR = 1.67 (95% CI 1.30; 2.16). CONCLUSION: In general, a positive association between phthalates and adiposity measures was found, especially in adults. However, most of the results did not reach statistical significance and the inconsistencies found between studies did not allow to reach a definitive conclusion. Additionally, we cannot exclude a possible effect of publication bias.