Effects of FTO and PPARγ variants on intrauterine growth restriction in a Brazilian birth cohort

Intrauterine growth restriction (IUGR) is related to a higher risk of neonatal mortality, minor cognitive deficit, metabolic syndrome, and cardiovascular disease in adulthood. In previous studies, genetic variants in the FTO (fat mass and obesity-associated) and PPARγ (peroxisome proliferator-activated receptor-gamma) genes have been associated with metabolic disease, body mass index, and obesity among other outcomes. We studied the association of selected FTO (rs1421085, rs55682395, rs17817449, rs8043757, rs9926289, and rs9939609) and PPARγ (rs10865710, rs17036263, rs35206526, rs1801282, rs28763894, rs41516544, rs62243567, rs3856806, and rs1805151) single-nucleotide polymorphisms (SNPs) with IUGR, through a case-control study in a cohort of live births that occurred from June 1978 to May 1979 in a Brazilian city. We selected 280 IUGR cases and 256 controls for analysis. Logistic regression was used to jointly analyze the SNPs as well as factors such as maternal smoking, age, and schooling. We found that the PPARγ rs41516544 increased the risk of IUGR for male offspring (OR 27.83, 95%CI 3.65-212.32) as well as for female offspring (OR=8.94, 95%CI: 1.96-40.88). The FTO rs9939609 TA genotype resulted in a reduced susceptibility to IUGR for male offspring only (OR=0.47, 95%CI: 0.26-0.86). In conclusion, we demonstrated that PPARγ SNP had a positive effect and FTO SNP had a negative effect on IUGR occurrence, and these effects were gender-specific.

Is soft drink consumption associated with gestational hypertension? Results from the BRISA cohort

It is still unknown whether excessive consumption of sugar-sweetened beverages may be linked to gestational hypertensive disorders, other than preeclampsia. This study investigated the association between soft drink consumption and hypertension during pregnancy, analyzing the relationship from the perspective of counterfactual causal theory. Data from pregnant women of the BRISA cohort were analyzed (1,380 in São Luis and 1,370 in Ribeirão Preto, Brazil). The explanatory variable was the frequency of soft drink consumption during pregnancy obtained in a prenatal interview. The outcome was gestational hypertension based on medical diagnosis, at the time of delivery. A theoretical model of the association between soft drink consumption and gestational hypertension was constructed using a directed acyclic graph. Marginal structural models (MSM) weighted by the inverse of the probability of soft drink consumption were also employed. Using Poisson regression analysis, high soft drink consumption (≥7 times/week) was associated with gestational hypertension in São Luís (RR=1.48; 95%CI: 1.03-2.10), in Ribeirão Preto (RR=1.51; 95%CI: 1.13-2.01), and in the two cohorts combined (RR=1.45; 95%CI: 1.16-1.82) compared to lower exposure (<7 times/week). In the MSM, the association between high soft drink consumption and gestational hypertension was observed in Ribeirão Preto (RR=1.63; 95%CI: 1.21-2.19) and in the two cohorts combined (RR=1.51; 95%CI: 1.15-1.97), but not in São Luís (RR=1.26; 95%CI: 0.79-2.00). High soft drink consumption seems to be a risk factor for gestational hypertension, suggesting that it should be discouraged during pregnancy.

Racial inequality in perinatal outcomes in two Brazilian birth cohorts

This study aimed to estimate and compare racial inequality in low birth weight (LBW), preterm birth (PTB), and intrauterine growth restriction (IUGR) in two Brazilian birth cohorts. This was a cross-sectional study nested within two birth cohorts in Ribeirão Preto (RP) and São Luís (SL), whose mothers were interviewed from January to December 2010. In all, 7430 (RP) and 4995 (SL) mothers were interviewed. The maternal skin color was the exposure variable. Associations were adjusted for socioeconomic and biological covariates: maternal education, per capita family income, family economic classification, household head occupation, maternal age, parity, marital status, prenatal care, type of delivery, maternal pre-pregnancy BMI, hypertension, hypertension during pregnancy, and smoking during pregnancy collected from questionnaires applied at birth. Statistical analysis was done with the chi-squared test and logistic regression. In RP, newborns from mothers with black skin color had a higher risk of LBW and IUGR, even after adjusting for socioeconomic and biological variables (P<0.001). In SL, skin color was not a risk factor for LBW (P=0.859), PTB (P=0.220), and IUGR (P=0.062), before or after adjustment for socioeconomic and biological variables. The detection of racial inequality in these perinatal outcomes only in the RP cohort after adjustment for socioeconomic and biological factors may be reflecting the existence of racial discrimination in the RP society. In contrast, the greater miscegenation present in São Luís may be reflecting less racial discrimination of black and brown women in this city.

Birth by cesarean section and mood disorders among adolescents of a birth cohort study in northern Brazil

The increasing number of cesarean sections worldwide has encouraged research on the long-term effects of this birth type on the offspring's mental health. The objective of this study was to investigate whether there is an association between birth by cesarean section and the development of mood disorders (depression and bipolar disorders) in adolescents. A cohort study was carried out with 1603 adolescents from 18 to 19 years old who participated in the third phase of a birth cohort study in São Luís, MA, in 2016. Information on birth type and weight, prematurity, mother's age and schooling, parity, marital status, and smoking behavior during pregnancy, were collected at birth. The study outcomes were depression, bipolar disorder, and "mood disorder" construct. A Directed Acyclic Graph (DAG) was developed to select the variables for minimal adjustment for confounding and collision bias. Associations were estimated through propensity score weighting using a two-step estimation model, and confounders for cesarean birth were used in the predictive model. There was no significant association in the relationship between birth type and depression (95%CI: -0.037 to 0.017; P=0.47), bipolar disorder (95%CI: -0.019 to 0.045; P=0.43), and mood disorder (95%CI: -0.033 to 0.042; P=0.80) in adolescents of both sexes. Birth by cesarean section was not associated with the development of mood disorders in adolescents.

Relative validity of a food frequency questionnaire for adolescents from a capital in the Northeastern region of Brazil

The present study was conducted to evaluate the validity of the Food Frequency Questionnaire (FFQ) used in the RPS Birth Cohort Consortium (Ribeirão Preto, Pelotas, and São Luís) to assess dietary intake of adolescents from São Luís, Maranhão. The research was developed with 152 adolescents aged 18 and 19 years. For the validation of the FFQ, the average of three 24-hour recalls (24HRs) was used as the reference method. The mean and standard deviation of energy and nutrient intake extracted from the surveys were estimated. The paired Student's t-test was used to verify the differences between the instruments. Pearson correlation coefficient, intraclass correlation coefficient (ICC), weighted Kappa, and the Bland-Altman plot were calculated in order to measure the agreement. The study adopted a level of significance <5%. Compared with the three 24HRs, the FFQ overestimated the consumption of most nutrients. Energy-adjusted and de-attenuated concordance Pearson correlation coefficients ranged from 0.06 to 0.43, and correlations were significant for iron, calcium, riboflavin, sodium, saturated fat, niacin, and vitamin C. The energy-adjusted and de-attenuated ICCs ranged from 0.01 to 0.31, and the weighted Kappa ranged from 0.01 to 0.46. The analyses of agreement were significant for vitamin C, fiber, calcium, riboflavin, niacin, sodium, lipids, and iron. In conclusion, the FFQ presented acceptable relative validity for lipids, saturated fatty acids, fiber, calcium, iron, riboflavin, niacin, vitamin C, and sodium. This instrument will be useful in studies about food consumption of adolescents in São Luís, Maranhão.

Association of genitourinary infections and cervical length with preterm childbirth

A prospective cohort study was conducted on a convenience sample of 1370 pregnant women with a gestational age of 20 to 25 weeks in the city of Ribeirão Preto. Data on obstetrical history, maternal age, parity, smoking habit, and a history of preterm delivery was collected with the application of a sociodemographic questionnaire. Cervical length was determined by endovaginal ultrasound, and urine and vaginal content samples were obtained to determine urinary tract infection (UTI) and bacterial vaginosis (BV), respectively. The aim of this study was to verify the association of cervical length and genitourinary infections with preterm birth (PTB). Ultrasound showed no association of UTI or BV with short cervical length. PTB rate was 9.63%. Among the women with PTB, 15 showed UTI (RR: 1.55, 95%CI: 0.93–2.58), 19 had BV (RR: 1.22, 95%CI: 0.77–1.94), and one had both UTI and BV (RR: 0.85, 95%CI: 0.13–5.62). Nineteen (14.4%) PTB occurred in women with a cervical length ≤2.5 cm (RR: 2.89, 95%CI: 1.89–4.43). Among the 75 patients with PTB stratified as spontaneous, 10 showed UTI (RR: 2.02, 95%CI: 1.05–3.86) and 14 had a diagnosis of BV (RR: 1.72, 95%CI: 0.97–3.04). A short cervical length between 20 and 25 weeks of pregnancy was associated with PTB, whereas UTI and BV determined at this age were not associated with short cervical length or with PTB, although UTI, even if asymptomatic, was related to spontaneous PTB.

Association between tobacco and/or alcohol consumption during pregnancy and infant development: BRISA Cohort

Fetuses exposed to alcohol and/or tobacco are at risk for perinatal adversities. However, little is currently known about the association of the separate or concomitant use of alcohol and tobacco with infant motor and cognitive development. Thus, the objective of the present study was to investigate the association between maternal consumption of alcohol and/or tobacco during pregnancy and the motor and cognitive development of children starting from the second year of life. The study included 1006 children of a cohort started during the prenatal period (22-25 weeks of pregnancy), evaluated at birth and reevaluated during the second year of life in 2011/2013. The children were divided into four groups according to the alcohol and/or tobacco consumption reported by their mothers at childbirth: no consumption (NC), separate alcohol consumption (AC), separate tobacco consumption (TC), and concomitant use of both (ACTC). The Bayley Scale of Infant and Toddler Development Third Edition screening tool was used for the assessment of motor and cognitive development. Adjusted Poisson regression models were used to determine the association between groups and delayed development. The results indicated that only the ACTC group showed a higher risk of motor delay, specifically regarding fine motor skills, compared to the NC group (RR=2.81; 95%CI: 1.65; 4.77). Separate alcohol or tobacco consumption was not associated with delayed gross motor or cognitive development. However, the concomitant use of the two substances increased the risk of delayed acquisition of fine motor skills.

Socio-environmental determinants of the delay in the first dental visit: results of two population-based cohort studies in Brazil

The objective of this study was to describe the timing of the first dental visit and investigate the association of socioeconomic and behavioral factors with dental visit delay among 10/11-year-old children from two live-birth population cohorts with extremely contrasting socioeconomic profiles. Follow-up data (2004-2005) from cohorts of Ribeirão Preto (RP) (n=790) and São Luís (SL) (n=673) were evaluated. Delay in dental visit was defined as not visiting a dentist before the age of 7. Covariates included family socioeconomic characteristics, mother-related health behavior, and child-related characteristics. Prevalence ratios with robust standard errors were estimated. In both cohorts, less than 5% of children had visited a dentist before the age of two and about 35% of them had not visited a dentist before the age of seven. Lower mother’s schooling and lack of private health insurance were associated with the delay in first dental visit for both cohorts. A small number of mother's prenatal care visits and being from a single-father family or a family without parents were only associated in the RP cohort, while having ≥4 siblings and lifetime dental pain were associated in the SL cohort. The association with dental pain probably reveals a preventive care-seeking behavior. Therefore, the percentage of delayed first dental visit of children was very high even among those with the most educated mothers. Further studies are necessary to analyze recent changes and underlying factors related to access to first dental visit after the implementation of the National Oral Health Policy in 2006.

Determinants of the introduction of early complementary feeding before and after the third month of life: a multinomial analysis

The introduction of early complementary feeding (ECF) is determined by different factors depending on when it occurs. The objective of this study was to analyze factors associated with the introduction of ECF in two different moments of the infant's life: from zero to three and from four to five months of age. A cohort with 3,306 dyads studied in the BRISA survey in São Luis/MA in 2010 was used. Questionnaires were applied at birth and at follow-up when the infants were 15 to 36 months of age of women with more than 20 weeks of gestational age, residing in this municipality. A multivariate model of multinomial logistic regression was used to verify associations between independent variables and ECF at 0 to 3 months and at 4 to 5 months of age. A hierarchical analysis model was used to select variables for confounding adjustment. Variables with a P-value <0.05 were considered significant. For ECF introduced between 0-3 months, the variables "use of pacifier", "maternal paid activity", "smoking", and "postpartum pregnancy" were identified as risk factors. The variables "use of pacifier" and "maternal paid activity" remained associated as a risk for ECF introduced from 4-5 months. The variable 'mother without partner' (RR=1.26 and P=0.04) represented a risk factor for ECF only for the 4-5 months period. Although each period presented specific risk factors, the use of pacifier and maternal professional activity were associated in the two periods studied, indicating their importance for the introduction of ECF.

Uterine vascular resistance and other maternal factors associated with the risk of developing hypertension during pregnancy

Gestational hypertension and pre-eclampsia are important causes of perinatal morbidity. The objective of the present study was to determine the increase in relative risk for developing hypertensive disorders of pregnancy based on the evaluation of pregnant women between 20 and 25 weeks of gestation, and to correlate the findings at this period with the outcome of pregnancy. We conducted a prospective cohort study, with a convenience sample of 1417 patients evaluated at this gestational age, of which 1306 were contacted at childbirth. We detected an increased relative risk of 2.69 (95%CI: 1.86 to 3.89) associated with pulsatility index of the uterine arteries, a 2.8 increase (95%CI: 1.58 to 5.03) in relative risk attributed to maternal age above 35 years, a 1.68 increase (95%CI: 1.17 to 2.40) attributed to parity greater than or equal to 3, and a 5.35 increase (95%CI: 4.18 to 6.85) attributed to chronic hypertension and obesity, with a progressive increase in relative risk according to the degree of overweight, i.e., grades 1, 2, 3, and morbid obesity (2.58, 3.06, 5.84, and 7.28, respectively).

Can increased resistance to uterine artery flow be a risk factor for adverse neurodevelopmental outcomes in childhood? A prospective cohort study

A prospective cohort study was conducted to determine whether an increased uterine artery pulsatility index (UtA-PI) in the second trimester of pregnancy is a risk factor for neurodevelopmental outcomes in children 2-3 years of age. A group of pregnant women with a UtA-PI below the 90th percentile (P90) and a second group with a UtA-PI ≥ P90 in the second trimester were included in this study. The children of these women were evaluated during their second or third year of life using the Bayley III Screening Test. A total of 858 pregnancies with UtA-PI < P90 and 96 pregnancies with UtA-PI ≥ 90 were studied. The differences between the groups related to UtA-PI ≥ 90 were detected in relation to the variables of the Caucasian ethnicity, hypertension, newborn weight and stay in the intensive care unit after birth. However, adjusted neurodevelopmental outcomes did not differ between the groups: OR 0.53 (95% CI 0.27-1.04%). This study failed to demonstrate that the UtA-PI is a risk factor for adverse neurodevelopment in children.Impact statementWhat is already known on this subject? Early interventions in children at high risk for neurodevelopmental deficiency have proved to be beneficial. The complications associated with gestation and delivery negatively influence neurodevelopment. Several studies have shown that some adverse pregnancy outcomes such as preeclampsia, foetal growth restriction and foetal death can be predicted by increased resistance to flow in the uterine artery in the second trimester. However, there are no studies evaluating the association of the uterine artery with neurodevelopmental results.What do the results of this study add? This study concludes that neurodevelopment is influenced by multiple environmental and intrinsic factors and cannot be predicted by only one variable, such as the uterine artery blood flow. The brain has repair mechanisms to attenuate insults that occur during gestation and delivery.What are the implications of these findings for clinical practice and/or further research? This study was unable to demonstrate that blood flow in the uterine artery is a risk factor for neurodevelopment. Different, larger studies should be conducted by combining other factors with the uterine artery in an algorithm to allow the early identification of children at risk for neurodevelopmental impairment.

Factors associated with vertical HIV transmission during two different time periods: the impact of zidovudine use on clinical practice at a Brazilian reference centre

Vertical HIV transmission rates and associated factors among mother-infant pairs cared for at a Brazilian reference centre from 1988 to 1993 (period 1), and from 1996 to 1999 (period 2) were evaluated. A total of 150 and 239 infants born to HIV+ mothers were enrolled at birth during these periods. No zidovudine prophylaxis was available in period 1. In period 2, 92.4% of the infants were exposed to zidovudine (54% started at delivery or in the post-natal period). During period 1, 25 of 129 infants were found to be infected (19.4%; 95% confidence interval [CI]=13-27) vs 20 of 232 (8.6%; 95% CI=5-13) during period 2 ( P <0.01). After controlling for co-variables, this decline was due to zidovudine prophylaxis, either with complete (odds ratio [OR]=0.24; 95% CI=0.08-0.70) or incomplete (OR=0.37; 95% CI=0.17-0.81) regimens. Premature rupture of membranes (OR =3.2) and rhesus-negative blood type of the infant (OR=2.6) facilitated transmission. Although confirming the protective effect of zidovudine prophylaxis, alternative approaches aimed at pregnant women identified late are needed for this population.

Birth weight, current body mass index, and insulin sensitivity and secretion in young adults in two Latin American populations

BACKGROUND AND AIMS

Although studies have shown association of birth weight (BW) and adult body mass index (BMI) with insulin sensitivity in adults, there is limited evidence that BW is associated with insulin secretion. We assessed the associations between BW and current BMI with insulin sensitivity and secretion in young Latin American adults.

METHODS AND RESULTS

Two birth cohorts, one from Ribeirao Preto, Brazil, based on 1984 participants aged 23-25 years, and another from Limache, Chile, based on 965 participants aged 22-28 years were studied. Weight and height at birth, and current fasting plasma glucose and insulin levels were measured. Insulin sensitivity (HOMA%S) and secretion (HOMA%β) were estimated using the Homeostatic Model Assessment (HOMA2). Multiple linear regression analyses were carried out to test the associations between BW and adult BMI z-scores on log HOMA%S and log HOMA%β. BW z-score was associated with HOMA%S in the two populations and HOMA%β in Ribeirao Preto when adult BMI z-score was included in the model. BW z-score was associated with decreasing insulin secretion even without adjusting for adult BMI, but only in Ribeirao Preto. BMI z-score was associated with low HOMA%S and high HOMA%β. No interactions between BW and BMI z-scores on insulin sensitivity were shown.

CONCLUSIONS

This study supports the finding that BW may affect insulin sensitivity and secretion in young adults. The effect size of BW on insulin status is small in comparison to current BMI.

Childhood socioeconomic position, adult socioeconomic position and social mobility in relation to markers of adiposity in early adulthood: evidence of differential effects by gender in the 1978/79 Ribeirao Preto cohort study

Background:

Longitudinal studies drawn from high-income countries demonstrate long-term associations of early childhood socioeconomic deprivation with increased adiposity in adulthood. However, there are very few data from resource-poor countries where there are reasons to anticipate different gradients. Accordingly, we sought to characterise the nature of the socioeconomic status (SES)-adiposity association in Brazil.

Methods:

We use data from the Ribeirao Preto Cohort Study in Brazil in which 9067 newborns were recruited via their mothers in 1978/79 and one-in-three followed up in 2002/04 (23–25years). SES, based on family income (salaries, interest on savings, pensions and so on), was assessed at birth and early adulthood, and three different adiposity measures (body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR)) ascertained at follow-up. The association between childhood SES, adult SES and social mobility (defined as four permutations of SES in childhood and adulthood: low–low, low–high, high–low, high–high), and the adiposity measures was examined using linear regression.

Results:

There was evidence that the association between SES and the three markers of adiposity was modified by gender in both adulthood (P<0.02 for all outcomes) and childhood SES (P<0.02 for WC and WHR). Thus, in an unadjusted model, linear regression analyses showed that higher childhood SES was associated with lower adiposity in women (coefficient (95% confidence intervals) BMI: −1.49 (−2.29,−0.69); WC: −3.85 (−5.73,−1.97); WHR: −0.03 (−0.04,−0.02)). However, in men, higher childhood SES was related to higher adiposity (BMI: 1.03 (0.28,−1.78); WC: 3.15 (1.20, 5.09); WHR: 0.009 (−0.001, 0.019)) although statistical significance was not seen in all analyses. There was a suggestion that adult SES (but not adult health behaviours or birthweight) accounted for these relationships in women only. Upward mobility was associated with protection against greater adiposity in women but not men.

Conclusion:

In the present study, in men there was some evidence that both higher childhood and adulthood SES was related to a higher adiposity risk, while the reverse gradient was apparent in women.

Growth after ventricular septal defect repair: does defect size matter? A 10-year experience

AIM

To evaluate whether the ventricular septal defect (VSD) size, along with the degree of preoperative growth impairment and age at repair, may influence postoperative growth, and if VSD size can be useful to identify children at risk for preoperative failure to thrive.

METHODS

Sixty-eight children submitted to VSD repair in a Brazilian tertiary-care institution were evaluated. Weight and height measurements were converted to Z-scores. Ventricular septal defect size was normalized by dividing it by the aortic root diameter (VSD/Ao ratio).

RESULTS

Twenty-six patients (38%) had significantly low weight-for-height, 10 patients (15%) had significantly low height-for-age and 13 patients (19%) had both conditions at repair. Catch-up growth occurred in 82% of patients for weight-for-age, in 75% of patients for height-for-age and in 89% of patients for weight-for-height. Weight-for-height Z-scores at surgery were significantly lower in patients who underwent repair before 9 months of age. The VSD/Ao ratio did not associate with any other data. On multivariate analysis, weight-for-age Z-scores and age at surgery were independent predictors of long-term weight and height respectively.

CONCLUSION

The VSD/Ao ratio was not a good predictor of preoperative failure to thrive. Most patients had preoperative growth impairment and presented catch-up growth after repair. Preoperative growth status and age at surgery influenced long-term growth.

Mineralocorticoid receptor p.I180V polymorphism: association with body mass index and LDL-cholesterol levels

BACKGROUND/AIMS

Aldosterone and the mineralocorticoid receptor (MR) play a major role in sodium balance and blood pressure control. They are also involved in adipocyte metabolism. The aim of this study was to analyze the association between the MR p.I180V polymorphism with hypertension and markers of cardiovascular risk.

DESIGN AND METHODS

Case-control study nested within a cohort of 2063 subjects followed since birth to date. All subjects (age 23-25 yr old) from the entire cohort with systolic and diastolic hypertension (no.=126) were paired with 398 normotensive controls. MR p.I180V genotype association with anthropometric and biochemical markers of cardiometabolic risk was tested.

RESULTS

There was a significant association of the MR p.I180V genotype with body mass index (BMI) and LDL-cholesterol level (p<0.01). Hypertensive subjects carrying the polymorphic G allele (AG or GG genotypes) presented significantly higher BMI (30.0+/-6.0 vs 28.7+/-5.6 kg/m(2); p<0.01) and higher LDL-cholesterol (139.9+/-60.3 vs 109.9+/-35.5 mg/dl; p<0.01). The frequency of the polymorphism MR p.I180V was similar between hypertensive subjects and controls (p=0.15).

CONCLUSIONS

The MR p.I180V polymorphism seems to be associated with cardiovascular risk factors including BMI and LDL-cholesterol levels. This original in vivo finding reinforces the role of MR in adipocyte biology and in cardiovascular disease.

High prevalence of polycystic ovary syndrome in women born small for gestational age

BACKGROUND

There is evidence that intrauterine growth restriction, resulting in newborn girls that are small for gestational age (SGA), may be related to the onset of polycystic ovary syndrome (PCOS). Thus, we studied whether women born SGA have a higher prevalence of PCOS than women born appropriate for gestational age (AGA).

METHODS

This was a prospective birth cohort study of 384 women born at term between June 1, 1978, and May 31, 1979, in Ribeirão Preto, Brazil. After exclusion, 165 women effectively participated in this study, of whom 43 were SGA and 122 were AGA. The prevalence of PCOS was analysed. At a mean age of 29 years, the women agreed to follow the study protocol, which included: anamnesis, physical examination, serum tests [follicle stimulating hormone, luteinizing hormone, total and free testosterone, dehydroepiandrostenedione sulphate, 17-OH-progesterone, fasting insulin, sex steroid-binding globulin (SHBG) and fasting glucose] and pelvic ultrasound. Data regarding gestational age, birthweight, age at menarche and maternal data were obtained from the files of the cohort. The adjusted relative risk (RR) values of the SGA, insulin resistance, body mass index, maternal smoking and parity variables were analysed using Poisson regression with robust adjustment of variance for the prediction of PCOS.

RESULTS

The prevalence of PCOS was higher in the SGA group than in the AGA group [adjusted RR = 2.44, 95% CI (1.39-4.28)]. Hyperandrogenism was more prevalent in the SGA women than in the AGA women (P = 0.011). Circulating SHBG was lower in the SGA women than in the AGA women (P = 0.041), but fasting insulinemia was similar in both groups.

CONCLUSIONS

The prevalence of PCOS in SGA women was twice as high as in AGA women in our study population.

Impact of specific sensitization on asthma and rhinitis in young Brazilian and Chilean adults

BACKGROUND

The pattern of associations and the attributable fractions (AF) of atopic conditions due to specific sensitizations vary between countries.

OBJECTIVE

To assess the level of associations and AF between sensitization to five allergens and atopic conditions in two settings.

METHODS

We studied 2063 Brazilians and 1231 Chileans of both sexes using representative samples selected at birth in the 1970s. Information on asthma and rhinitis was based on the European Community Respiratory Health Survey questionnaire. We assessed bronchial hyperresponsiveness (BHR) to methacholine and sensitization to Dermatophagoides pteronyssinus, cat, dog, grass blend and Alternaria alternata.

RESULTS

The prevalence of sensitization to one or more allergens was 50% in Brazilians and 22% in Chileans. The level of associations varied according to the outcome used. Strong associations between sensitization and asthma, defined as wheeze or awakening with breathlessness at night and positive BHR, were found for each of the five allergens in Chileans [varying from odds ratio (OR) 3.24, 95% confidence interval (CI) 1.47, 7.15 for D. pteronyssinus to 8.44, 95% CI 3.82, 18.66 for cat], whereas the level of associations was restricted to D. pteronyssinus, cat and dog in Brazilians and was somewhat weaker (highest OR 3.90, 95% CI 2.80-5.44). The AF of sensitization on asthma was 54% in Brazil and 44% in Chile. D. pteronyssinus and cat made an independent contribution to asthma in the two samples. The patterns of associations between sensitization and rhino-conjunctivitis were similar to those for asthma.

CONCLUSION

The associations between sensitization, and asthma and rhinitis were high in Chile and moderately high in Brazil, but the AF were higher in Brazil, reflecting a higher prevalence of sensitization. In Brazil, dust mite had the greatest impact on atopic conditions while in Chile several allergens had an impact. Sensitization is as serious a problem in Chile and Brazil as in developed countries.

Asthma definitions, relative validity and impact on known risk factors in young Brazilians

BACKGROUND

An asthma score was proposed in the European Community Respiratory Health Survey (ECRHS) framework, as dichotomous definitions could be less appropriate in the study of chronic diseases. The aims of this study were to assess the value of this asthma score in comparison with other definitions of asthma in another population setting, using as criteria bronchial hyperresponsiveness (BHR) to methacholine and diagnosed asthma, and the association of these definitions to known risk factors of asthma.

METHODS

We used the ECRHS questionnaire on 2063 Brazilians, aged 23-25 years, and measured their BHR. We assessed the positive and negative likelihood ratios (PLR and NLR) of the asthma score (0-8), a three question score (ECRHS definition) and single asthma symptoms in relation to BHR and diagnosed asthma.

RESULTS

The PLR were relatively low for all asthma definitions with odd ratios varying from 1.47 for asthma score to 5.50 for wheeze and waking with breathlessness without a cold. The NLR were near 1. The PLR were lower for assessments using the score than for dichotomous assessments or the ECRHS definition. The PLR increased with asthma scores, but the prevalence with higher scores was too low for useful analysis. The asthma score was slightly better for identifying associations from a set of known risk factors than the other two approaches.

CONCLUSION

Our study provided little support for a greater validity of this asthma score over other asthma definitions, and only marginal advantage for identifying risk factors.

Are birth weight and maternal smoking during pregnancy associated with malnutrition and excess weight among school age children?

In the late 1980's child malnutrition was still prevalent in Brazil, and child obesity was beginning to rise in the richest regions of the country. To assess the extent of the nutritional transition during the period and the influence of birth weight and maternal smoking on the nutritional condition of schoolchildren, we estimated the prevalence of excess weight and malnutrition in a cohort of Brazilian schoolchildren from 1987 to 1989. We calculated the body mass index (BMI) of 8- to 10-year-old schoolchildren born in Ribeirão Preto in 1978/79. We considered children with a BMI <5th percentile (P5) to be malnourished, children with P5 > or = BMI<P85 to be thin and normal, and children with BMI > or = P85 to be overweight. We evaluated the association of these nutritional disorders with birth factors (infant weight, sex, preterm delivery, number of pregnancies, maternal smoking during pregnancy, marital status, and schooling) and type of school using nominal logistic regression. A total of 2797 schoolchildren were evaluated. There was a significant prevalence of malnutrition (9.5%) and excess weight already tended to increase (15.7%), while 6.4% of the children were obese. Excess weight was more prevalent among children attending private schools (odds ratio, OR = 2.27) and firstborn children (OR = 1.69). Maternal smoking during pregnancy protected against malnutrition (OR = 0.56), while children with lower birth weight were at higher risk for malnutrition (OR = 4.23). We conclude that a nutritional transition was under way while malnutrition was still present, but excess weight and related factors were already emerging.