Food consumption by young adults living in Ribeirão Preto, SP, 2002/2004

There is evidence showing a close relationship between diet and the occurrence of non-communicable chronic diseases. The present study assessed food consumption in a 2002/2004 cohort of young adults born in 1978/79 in Ribeirão Preto, SP, Brazil. The composition of the habitual diet consumed by a sample of 2063 individuals aged 23-25 years was analyzed using a validated semi-quantitative food frequency questionnaire based on studies of prevention of non-communicable chronic diseases. The Dietsys software was used for dietary calculations. In terms of WHO/2003 recommendations, there was a high mean daily consumption of energy from fat (consumption: 35.4%; recommendation: 15-30%), a low mean intake of energy from carbohydrates (47.5%; 55-75%) and a low mean consumption of total fibers (15.2 g; >25 g). Mean intake of energy from fatty acids (10%; <10%) and protein (15.6%; 10-15%) was within recommended limits. When compared to the recommendations of the food pyramid adapted to the Brazilian population, adequate intake was observed only regarding the meat group (consumption: 1.9 portions; recommended: 1-2). There was a low consumption of vegetables (2.9; 4-5), fruits (1.2; 3-5), breads (3.6; 6-9), and dairy products (1.7; 3), with excessive fat and sugar intake (5.7; 1-2). We conclude that the inadequate food consumption observed in this young population may be associated with the development of excess weight and may contribute to the triggering of non-communicable chronic diseases.

Do socioeconomic factors explain why maternal smoking during pregnancy is more frequent in a more developed city of Brazil?

The prevalence of smoking during pregnancy in Ribeirão Preto, a rich Brazilian city, was significantly higher (21.4%) than in São Luís (5.9%), a less developed city. To assess which variables explain the difference in prevalence of smoking during pregnancy, data from two birth cohorts were used, including 2846 puerperae from Ribeirão Preto, in 1994, and 2443 puerperae from São Luís, in 1997/98. In multivariable analysis, risk of maternal smoking during pregnancy was higher in São Luís for mothers living in a household with five or more persons (OR = 1.72, 95%CI = 1.12-2.64), aged 35 years or older (OR = 1.98, 95%CI = 0.99-3.96), who had five or more children (OR = 2.10, 95%CI = 1.16-3.81), and whose companion smoked (OR = 2.20, 95%CI = 1.52-3.18). Age of less than 20 years was a protective factor (OR = 0.55, 95%CI = 0.33-0.92). In Ribeirão Preto there was association with maternal low educational level (OR = 2.18, 95%CI = 1.30-3.65) and with a smoking companion (OR = 3.25, 95%CI = 2.52-4.18). Receiving prenatal care was a protective factor (OR = 0.24, 95%CI = 0.11-0.49). Mothers from Ribeirão Preto who worked outside the home were at a higher risk and those aged 35 years or older or who attended five or more prenatal care visits were at lower risk of smoking during pregnancy as compared to mothers from São Luís. Smoking by the companion reduced the difference between smoking rates in the two cities by 10%. The socioeconomic variables in the model did not explain the higher prevalence of smoking during pregnancy in the more developed city.

Why are the rates of cesarean section in Brazil higher in more developed cities than in less developed ones?

The objective of the present study was to investigate factors associated with cesarean sections in two cities located in different regions of Brazil and to determine factors that explain the higher cesarean section rate in the more developed city, Ribeirão Preto, compared to the less developed one, São Luís. Data from two cohort studies comprising 2846 women in Ribeirão Preto in 1994, and 2443 women in São Luís in 1997/1998 were used. Adjusted and non-adjusted risk estimates were calculated using a Poisson regression model. The cesarean section rate was 33.7% in São Luís and 50.8% in Ribeirão Preto. Adjusted analysis in a joint sequential model revealed a 51% higher risk of cesarean section in Ribeirão Preto compared to São Luís (prevalence rate ratio (PRR) = 1.51). Adjustment for category of hospital admission reduced the PRR to 1.09, i.e., this variable explained 82% of the difference in the cesarean section rate between the two cities. Adjustment for the variable "the same physician for prenatal care and delivery" reduced the PRR to 1.07, with the "physician" factor explaining 86% of the difference between rates. When simultaneously adjusted for the two variables, the PRR decreased to 1.05, with these two variables explaining 90% of the difference in the cesarean section rate between the two cities, and the difference was no longer significant. The difference in the cesarean section rate between the two Brazilian cities, one more and one less developed, was mainly explained by the physician factor and, to a lesser extent, by the category of hospital admission.

Racial inequalities and perinatal health in the southeast region of Brazil

Few studies are available about racial inequalities in perinatal health in Brazil and little is known about whether the existing inequality is due to socioeconomic factors or to racial discrimination per se. Data regarding the Ribeirão Preto birth cohort, Brazil, whose mothers were interviewed from June 1, 1978 to May 31, 1979 were used to answer these questions. The perinatal factors were obtained from the birth questionnaire and the ethnic data were obtained from 2063 participants asked about self-reported skin color at early adulthood (23-25 years of age) in 2002/2004. Mothers of mulatto and black children had higher rates of low schooling (< or = 4 years, 27.2 and 38.0%) and lower family income (< or = 1 minimum wage, 28.6 and 30.4%). Mothers aged less than 20 years old predominated among mulattos (17.0%) and blacks (14.0%). Higher rates of low birth weight and smoking during pregnancy were observed among mulatto individuals (9.6 and 28.8%). Preterm birth rate was higher among mulattos (9.5%) and blacks (9.7%) than whites (5.5%). White individuals had higher rates of cesarean delivery (34.9%). Skin color remained as an independent risk factor for low birth weight (P < 0.001), preterm birth (P = 0.01), small for gestational age (P = 0.01), and lack of prenatal care (P = 0.02) after adjustment for family income and maternal schooling, suggesting that the racial inequalities regarding these indicators are explained by the socioeconomic disadvantage experienced by mulattos and blacks but are also influenced by other factors, possibly by racial discrimination and/or genetics.

Do intrauterine growth restriction and overweight at primary school age increase the risk of elevated body mass index in young adults?

Obesity is one of the rising public health problems characterized as a risk factor for many chronic diseases in adulthood. Early life events such as intrauterine growth restriction, as well as life style, are associated with an increased prevalence of this disease. The present study was performed to determine if intrauterine growth restriction interacts with overweight at primary school age to affect body mass index (BMI) in young adults. From June 1, 1978 to May 31, 1979, 6827 singleton liveborns from Ribeirão Preto, São Paulo State, Brazil, corresponding to 98% of all births at the 8 maternity hospitals, were examined and their mothers were interviewed. Samples from the initial cohort were examined again at primary school age (8 to 11 years of age) and at the time of military service (18 years of age). There were 519 male individuals with complete measurements taken in the three surveys. Intrauterine growth-restricted individuals had a BMI 0.68 kg/m(2) lower than that of individuals who were not restricted (95%CI = -1.34 to -0.03) and overweight at primary school age showed a positive and strong effect on BMI at 18 years of age (coefficient 5.03, 95%CI = 4.27 to 5.79). However, the increase in BMI was much higher--6.90 kg/m(2)--when the conscript had been born with intrauterine growth restriction and presented overweight at primary school age (95%CI = 4.55 to 9.26). These findings indicate that the effect of intrauterine growth restriction on BMI at 18 years of age is modified by later weight gain during school age.

Social inequality and perinatal health: comparison of three Brazilian cohorts

The objective of the present study was to estimate and compare social inequality in terms of three indicators, i.e., low birth weight (LBW), preterm birth (PTB) and small for gestational age (SGA) birth, in three birth cohorts. Two cohorts were from the city of Ribeirão Preto, where data were collected for all 6748 live born singletons in 1978/79 and for one third of live born singletons (2846) in 1994. The third cohort consisted of 2443 singletons born in São Luís over a period of one year (1997/98). In Ribeirão Preto, LBW and PTB rates increased in all social strata from 1978/79 to 1994. Social inequalities regarding LBW and PTB disappeared since the increase in these rates was more accelerated in the groups with higher educational level. The percentage of SGA infants increased over the study period. Social inequality regarding SGA birth increased due to a more intense increase in SGA births in the strata with lower schooling. In São Luís, in 1997/98 there was no social inequality in LBW or PTB rates, whereas SGA birth rate was higher in mothers with less schooling. We speculate that the more accelerated increase in medical intervention, especially due to the increase in cesarean sections in the more privileged groups, could be the main factor explaining the unexpected increase in LBW and PTB rates in Ribeirão Preto and the decrease or disappearance of social inequality regarding these perinatal indicators in the two cities.

Early life, current socioeconomic position and serum lipids in young adulthood of participants in a cohort study initiated in 1978/1979

The association between socioeconomic position (SEP) and serum lipids has been little studied and the results have been controversial. A total of 2063 young adults born in 1978/79 were evaluated at 23-25 years of age in the fourth follow-up of a cohort study carried out in Ribeirão Preto, SP, Brazil, corresponding to 31.8% of the original sample. Total serum cholesterol (TC), triglycerides, high-density cholesterol (HDL cholesterol) and low-density cholesterol (LDL cholesterol) were analyzed according to SEP at birth and during young adulthood. SEP was classified into tertiles of family income and a cumulative score of socioeconomic disadvantage was created. TC was 11.85 mg/100 mL lower among men of lower SEP in childhood (P < 0.01) but no difference was found in women, whereas it was 8.46 lower among men (P < 0.01) and 8.21 lower among women of lower SEP in adulthood (P < 0.05). Individuals of lower SEP had lower LDL and HDL cholesterol, with small differences between sexes and between the two times in life. There was no association between SEP and triglyceride levels. After adjustment of income at one time point in relation to the other, some associations lost significance. The greater the socioeconomic disadvantage accumulated along life, the lower the levels of TC, LDL and HDL cholesterol (P < 0.05). The socioeconomic gradient of TC and LDL cholesterol was inverse, representing a lower cardiovascular risk for individuals of lower SEP, while the socioeconomic gradient of HDL cholesterol indicated a lower cardiovascular risk for individuals of higher SEP.

Profile of three Brazilian birth cohort studies in Ribeirão Preto, SP and São Luís, MA

We describe three birth cohort studies, respectively carried out in 1978/79 and 1994 in Ribeirão Preto, a city located in the most developed region of Brazil, and in 1997/98 in São Luís, a city located in a less developed region. The objective of the present report was to describe the methods used in these three studies, presenting their history, methodological design, objectives, developments, and difficulties faced along 28 years of research. The first Ribeirão Preto study, initially perinatal, later encompassed questions regarding the repercussions of intrauterine development on future growth and chronic adult diseases. The subjects were evaluated at birth (N = 6827), at school age (N = 2861), at the time of recruitment for military service (N = 2048), and at 23/25 years of age (N = 2063). The study of the second cohort, which started in 1994 (N = 2846), permitted comparison of aspects of perinatal health between the two groups in the same region, such as birth weight, mortality and health care use. In 1997/98, a new birth cohort study was started in São Luís (N = 2443), capital of the State of Maranhão. The 1994 Ribeirão Preto cohort and the São Luís cohort are in the second phase of joint follow-up. These studies permit comparative temporal analyses in the same place (Ribeirão Preto 1978/79 and 1994) and comparisons of two contrasting populations regarding cultural, economic and sociodemographic conditions (Ribeirão Preto and São Luís).

Factors associated with infant and adolescent mortality

Few studies have described factors associated with infant and adolescent mortality since birth. We report here mortality during a 20-year period in a birth cohort from Ribeirão Preto in order to identify birth variables that influenced mortality among infants and children between 10 and 19 years of age, the main causes of death, and the influence of social inequality at birth on death. Mothers were interviewed shortly after delivery. Social, biological and demographic information was collected, and mortality up to 19 years of age was investigated in registry systems. Of the 6748 liveborn singletons born in the municipality from 1978 to 1979, 343 died before or when 19 years of age were completed. Most of the cohort mortality (74.9%) occurred during the first year of life and 19.6% occurred from 10 to 19 years. Mortality was higher among boys. Preterm birth (hazard ratio, HR = 7.94) and low birth weight (HR = 10.15) were strongly associated with infant mortality. Other risk factors for infant mortality were: maternal age (3)35 years (HR = 1.74), unskilled manual occupation of family head (HR = 2.47), and for adolescent mortality: unskilled manual occupation of family head (HR = 9.98) and male sex (HR = 6.58). "Perinatal conditions" were the main causes of deaths among infants and "external causes" among adolescents, especially boys. Socioeconomic factors at birth, represented by occupation, influenced adolescent mortality due to external causes, which was higher among boys (7:1). The influence of social inequality at birth on death, measured by occupation, was greater in adolescence than in infancy.

Do early life factors influence body mass index in adolescents?

The association between early life factors and body mass index (BMI) in adulthood has been demonstrated in developed countries. The aim of the present study was to assess the influence of early life factors (birth weight, gestational age, maternal smoking, and social class) on BMI in young adulthood with adjustment for adult socioeconomic position. A cohort study was carried out in 1978/79 with 6827 mother-child pairs from Ribeirão Preto city, located in the most developed economic area of the country. Biological, economic and social variables and newborn anthropometric measurements were obtained shortly after delivery. In 1996, 1189 males from this cohort, 34.3% of the original male population, were submitted to anthropometric measurements and were asked about their current schooling on the occasion of army recruitment. A multiple linear regression model was applied to determine variables associated with BMI. Mean BMI was 22.7 (95%CI = 22.5-23.0). After adjustment, BMI was 1.22 kg/m(2) higher among infants born with high birth weight ( > or = 4000 g), 1.21 kg/m(2) higher among individuals of low social class at birth and 0.69 kg/m(2) higher among individuals whose mothers smoked during pregnancy (P < 0.05). The association between social class at birth and BMI remained statistically significant (P < 0.05) even after adjustment for adult schooling. These findings suggest that early life social influences on BMI were more important and were not reversed by late socioeconomic position. Therefore, prevention of overweight and obesity should focus not only on changes in adult life styles but also on factors such as high birth weight.

Inadequate utilization of prenatal care in two Brazilian birth cohorts

Data for two birth cohorts from two Brazilian municipalities, Ribeirão Preto in 1994 and São Luís in 1997/1998, were used to identify and compare factors associated with inadequate utilization of prenatal care and to identify factors capable of explaining the differences observed between the two cities. Prenatal care was defined as adequate or inadequate according to the recommendations of the Brazilian Ministry of Health. The chi-square test and Poisson regression were used to compare differences in the inadequacy of prenatal care utilization. The percentage of inadequacy was higher in São Luís (34.6%) than in Ribeirão Preto (16.9%). Practically the same variables were associated with inadequacy in both cities. Puerperae with lower educational level, without a companion or cohabiting, who delivered in public health units, younger than 20 years, multiparae and smokers, with low family income presented higher percentages of inadequate prenatal care utilization. However, the effects of some variables differed between the two cities. The risk for inadequate use of prenatal care was higher for women attended in the public health sector in São Luís and for cohabiting women in Ribeirão Preto. The effect of the remaining factors studied did not differ between cities. The category of admission accounted for 57.0% of the difference in the inadequate use of prenatal care between cities and marital status accounted for 45.3% of the difference. Even after adjustment for all variables, part of the difference in the inadequacy of prenatal care utilization remained unexplained.

Health in early adulthood: the contribution of the 1978/79 Ribeirão Preto birth cohort

The increase in non-communicable chronic diseases of adults is due to demographic changes and changes in the risk factors related to physical activity, smoking habits and nutrition. We describe the methodology for the evaluation of persons at 23/25 years of age of a cohort of individuals born in Ribeirão Preto in 1978/79. We present their socioeconomic characteristics and the profile of some risk factors for chronic diseases. A total of 2063 participants were evaluated by means of blood collection, standardized questionnaires, anthropometric and blood pressure measurements, and methacholine bronchoprovocation tests. The sexes were compared by the chi-square test, with alpha = 0.05. Obesity was similar among men and women (12.8 and 11.1%); overweight was almost double in men (30.3 vs 17.7%). Weight deficit was higher among women than among men (8.6 and 2.6%). Women were more sedentary and consumed less alcohol and tobacco. Dietary fat consumption was similar between sexes, with 63% consuming large amounts (30 to 39.9 g/day). Metabolic syndrome was twice more frequent among men than women (10.7 vs 4.8%), hypertension was six times more frequent (40.9 vs 6.4%); altered triglyceride (16.1 vs 9.8%) and LDL proportions (5.4 vs 2.7%) were also higher in men, while women had a higher percentage of low HDL (44.7 vs 39.5%). Asthma and bronchial hyper-responsiveness were 1.7 and 1.5 times more frequent, respectively, among women. The high prevalence of some risk factors for chronic diseases among young adults supports the need for investments in their prevention.

Prevalence and risk factors for work related asthma in young adults

OBJECTIVES

To investigate the prevalence and predictors of work related asthma in young adults from the general population.

METHODS

A total of 1922 subjects randomly selected from a birth cohort 1978/79 in Brazil, aged 23-25 years, completed a respiratory symptoms questionnaire based on the European Community Respiratory Health Survey, and underwent spirometry, bronchial challenge test with methacholine, and skin prick test. For subjects presenting with bronchial hyperresponsiveness, workplace exposure and its relationship with symptoms were assessed by a specific questionnaire and individualised job description to define cases of work related asthma.

RESULTS

The prevalence of work related asthma was 4.2% (81 cases): 1.5% (29 cases) were classified as aggravated asthma and 2.7% (52 cases) as occupational asthma. Work related asthma was associated with atopy and education. Lower educational level (1-8 years of schooling) was associated with work related asthma (odds ratio 7.06, 95% CI 3.25 to 15.33). There was no association between work related asthma and smoking, gender, or symptoms of rhinitis.

CONCLUSION

The prevalence of work related asthma was high (4.2%), and was associated with low schooling, probably because of low socioeconomic level. The disease may therefore be a consequence of poverty.

The relative strength of weight and length at birth in contrast to social factors as determinants of height at 18 years in Brazil

BACKGROUND

There is scarce information on the relative importance of measurements at birth and social factors in determining adult height.

AIM

To assess the relative contribution of length and weight at birth, and social factors to height at 18 years.

METHODS

A total of 3470 boys born in Ribeirão Preto, Brazil, in 1978/1979 were reassessed at the time of military conscription. Anthropometric, demographic and social variables were collected concurrently and used in a multiple regression analysis.

RESULTS

A total of 2029 (61.3%) of the target population were assessed at 18 years. In the adjusted analysis, birth length, birth weight, social class, neighbourhood wealth of subject, maternal age and birth order were highly associated with height at 18 years. The results were similar when birth weight and length at birth were included as continuous or categorical variables. The differences in height due to length at birth were greater than those due to social factors.

CONCLUSIONS

This study has demonstrated the lasting and greater effect of length and weight at birth on height in comparison to social factors, but social factors are still meaningful in their effects on height. Birth length has a marginal greater effect on final height than birth weight.

Risk factors for low birthweight in north-east Brazil: the role of caesarean section

Caesarean section (CS) delivery is associated with low birthweight (LBW) in south-east Brazil. A hospital-based study was conducted on singleton infants from mothers residing in São Luís, to assess if an association between CS and LBW was found in the northern part of the country, where the CS rate is lower than in the south-east. A standardised questionnaire was administered to a sample of 2541 mothers in 10 hospitals, representing 94% of all deliveries, from March 1997 to February 1998. In a logistic model, type of delivery was the independent variable, the other variables were treated as confounders, and interaction terms were added between type of delivery and all other factors. LBW was associated with low maternal height, maternal smoking, primiparity, previous LBW, public insurance, preterm birth and CS. The CS rate was 33.7%. The risk of CS was higher for primiparous and married mothers, those with high level of schooling and attended by the same physician during prenatal and delivery care, deliveries held in private hospitals, daylight hours or evenings, and for those mothers who had adequate prenatal care. Because it appears unlikely that only medical reasons are operative, it is a possibility that CS could cause LBW, reflecting abusive indications for elective CS.

Infant mortality rates according to socioeconomic status in a Brazilian city

OBJECTIVE

Data from municipal databases can be used to plan interventions aimed at reducing inequities in health care. The objective of the study was to determine the distribution of infant mortality according to an urban geoeconomic classification using routinely collected municipal data.

METHODS

All live births (total of 42,381) and infant deaths (total of 731) that occurred between 1994 and 1998 in Ribeirão Preto, Brazil, were considered. Four different geoeconomic areas were defined according to the family head's income in each administrative urban zone.

RESULTS

The trends for infant mortality rate and its different components, neonatal mortality rate and post-neonatal mortality rate, decreased in Ribeirão Preto from 1994 to 1998 (chi-square for trend, p<0.05). These rates were inversely correlated with the distribution of lower salaries in the geoeconomic areas (less than 5 minimum wages per family head), in particular the post-neonatal mortality rate (chi-square for trend, p<0.05). Finally, the poor area showed a steady increase in excess infant mortality.

CONCLUSIONS

The results indicate that infant mortality rates are associated with social inequality and can be monitored using municipal databases. The findings also suggest an increase in the impact of social inequality on infant health in Ribeirão Preto, especially in the poor area. The monitoring of health inequalities using municipal databases may be an increasingly more useful tool given the continuous decentralization of health management at the municipal level in Brazil.

Clinical experience with infants with Robin sequence: a prospective study

OBJECTIVE

To study the clinical course of patients with Robin sequence (RS) during the first 6 months of life.

DESIGN

A longitudinal prospective study of children with RS.

SETTING

Hospital de Reabilitação de Anomalias Craniofaciais, Universidade de São Paulo, Bauru-SP, Brazil, 1997 and 1998.

PATIENTS

Sixty-two children were studied from hospital admission to 6 months of age. Thirty-three (53.2%) presented with probable isolated RS (PIRS), 25 (40.3%) presented with syndromes or other malformations associated with RS, and 4 (6.5%) presented with RS with neurological involvement.

INTERVENTIONS

The type of respiratory tract obstruction was defined by nasopharyngoscopy. The patients with type 1 and type 2 obstruction underwent nasopharyngeal intubation (NPI), and glossopexy was indicated in patients with type 1 obstruction who did not show clinical improvement with this procedure. Tracheostomy was indicated in patients with type 2 obstruction who did not show a good course after NPI, in patients with type 1 obstruction who did not show good course after glossopexy, and in patients with type 3 and type 4 obstruction.

RESULTS

Prone position treatment (PPT) or NPI was the definitive treatment in 25 cases (75.8%) of PIRS and in 13 cases (52%) of syndromes or other malformations. Among the children with type 1 obstruction, 24 (51.1%) were submitted exclusively to PPT and 12 (25.5%) to NPI. With the type 2 groups, only one (12.5%) received PPT, and three (37.5%) were treated exclusively with NPI. All 15 infants treated exclusively with NPI (24.4%) presented with good weight, length, and neuromotor development.

CONCLUSIONS

Most patients with PIRS and type 1 obstruction improved without surgical intervention. NPI should be the initial treatment in all patients with RS with type 1 and type 2 obstruction who present with important respiratory and feeding difficulties.

Risk factors for the increasing trend in low birth weight among live births born by vaginal delivery, Brazil

OBJECTIVE

To identify risk factors for low birth weight (LBW) among live births by vaginal delivery and to determine if the disappearance of the association between LBW and socioeconomic factors was due to confounding by cesarean section.

METHODS

Data were obtained from two population-based cohorts of singleton live births in Ribeirão Preto, Southeastern Brazil. The first one comprised 4,698 newborns from June 1978 to May 1979 and the second included 1,399 infants born from May to August 1994. The risks for LBW were tested in a logistic model, including the interaction of the year of survey and all independent variables under analysis.

RESULTS

The incidence of LBW among vaginal deliveries increased from 7.8% in 1978--79 to 10% in 1994. The risk was higher for: female or preterm infants; newborns of non-cohabiting mothers; newborns whose mothers had fewer prenatal visits or few years of education; first-born infants; and those who had smoking mothers. The interaction of the year of survey with gestational age indicated that the risk of LBW among preterm infants fell from 17.75 to 8.71 in 15 years. The mean birth weight decreased more significantly among newborns from qualified families, who also had the highest increase in preterm birth and non-cohabitation.

CONCLUSIONS

LBW among vaginal deliveries increased mainly due to a rise in the proportion of preterm births and non-cohabiting mothers. The association between cesarean section and LBW tended to cover up socioeconomic differences in the likelihood of LBW. When vaginal deliveries were analyzed independently, these socioeconomic differences come up again.

Maternal age, social changes, and pregnancy outcome in Ribeirão Preto, southeast Brazil, in 1978-79 and 1994

This study focused on changes in demographic, social, and health-care patterns and pregnancy outcome related to maternal age from 1978-79 to 1994 in Ribeirão Preto, São Paulo State, Brazil. Information on pregnancy outcome was obtained from two cohorts of singleton live births, 6,681 births in 1978/79 and 2,839 births in 1994. A standardized questionnaire was submitted to mothers after delivery, and demographic information was collected from official records. There was a significant increase in teenage pregnancies (from 5.1% to 7.4%) and a decrease in infant mortality (36/1,000 to 17/1,000). There were significant decreases in the proportion of mothers with low schooling (24.5% to 14.4%), smoking (28.9% to 21.%), and multiparity (14.7% to 9.0%). Prenatal coverage improved (from 23.4% to 9.0% of patients with fewer than 4 prenatal visits), while cesareans increased (from 30.6% to 50.8%), as did preterm delivery (7.2% to 13.6%) and low birthweight (7.2% to 10.6%). Despite significant improvements in some maternal characteristics, the proportion of teenage pregnancies, preterm deliveries, low birthweight, and cesareans increased, raising concerns about the health costs and consequences for mothers and infants.

[Age at menarche among schoolgirls from a rural community in Southeast Brazil]

The purpose of this study was to determine the 3rd percentile (P3), 50th percentile (P50 = median age at menarche = MAM), and amplitude between the extremes (P97 and P3) of age at menarche among schoolgirls in the county of Barrinha, São Paulo, Brazil. Values were correlated with socioeconomic conditions such as social class, number of siblings, and father's employment status. This was a cross-sectional study based on the use of status quo adjusted by logit for calculation of percentiles. A questionnaire was applied to 1,602 schoolgirls aged 8 to 17 years (incomplete). MAM was 12 years (y) and 6 months (m), with a P97 of 10 y and 2 m and a P3 of 14 y and 10 m. Girls from lower-income families and those with unemployed fathers showed later MAM. No difference in MAM was observed with respect to number of siblings. Amplitude between P97 ad P3 was great in the overall sample. We conclude that Barrinha presented a MAM similar to and even lower than regional values for Brazil and for some developed countries. The study of the interval between extreme percentiles proved to be a better indicator of biological diversity and socioeconomic inequality than MAM alone.

[Comparison between two cohorts of adolescent mothers in municipality of the Southeastern, Brazil]

OBJECTIVE

To compare the prevalence of pregnancy among adolescents and analyze trends in some social and biological variables among two cohorts of adolescent mothers in Ribeirão Preto, Brazil, during 1978/79 and 1994.

METHODS

Two cohorts of adolescent mothers were interviewed shortly after delivery, comprising 943 women in the first survey (1978/79) and 499 in the second (1994). Both surveys covered more than 98% of births in all childbirth clinics. Only singleton livebirths from adolescent mothers living in the municipality were included in the analysis. The Chi-square test was used for statistical analysis, with a 0.05 significance level.

RESULTS

The percentage of adolescent mothers increased from 14.1% in 1978/79 to 17.5% in 1994 (p<0.05), mainly due to an increase in deliveries in the 13-17 years age group. There was a reduction in the number of smokers and mothers with lower schooling. The number of prenatal care visits increased. There was also an increase in the proportion of single mothers, of those who were employed and got private delivery care. Low birth weight and preterm birth rates remained unchanged for all of them. Cesarean section and forceps delivery rates increased substantially. Mothers in the 13-17 years age group however showed twice as much premature and low birth weight children, a higher proportion of single mothers with lower schooling, and higher rate of forceps delivery.

CONCLUSIONS

Some characteristics of the adolescent mothers in the 13-17 years age group were more unfavorable when compared to the 18-19 years age group. The characteristics of adolescent age groups need to be better understood and taken into account in the prenatal and delivery care planning.

Factors associated with preterm births in southeast Brazil: a comparison of two birth cohorts born 15 years apart

An increase in preterm deliveries in Ribeirão Preto stimulated an analysis of possible explanatory factors. Two cohorts of singleton livebirths were studied, the first based on 6746 births in 1978-9 and the second based on 2846 births in 1994. A logistic regression was carried out to assess the association of preterm birth with several sociodemographic, behavioural and clinical variables, including year of survey. Delivery in private settings compared with a public setting, maternal age of < or = 17 compared with any other age group, and mothers who had had previous abortions and previous stillbirths were associated with greater rates of preterm birth. Although there was an increase in preterm birth rates regardless of mode of delivery, the increase was greater in the caesarean section group than in the vaginal delivery group. Over the study period, deliveries in private hospitals and caesarean section operations increased markedly (from 4% to 36% and from 30% to 51% respectively). Caesarean section may be the main contributor to the increase of preterm birth rate in this study. It is essential to ensure that health-care staff, especially those in private facilities, are properly educated and audited.

Risk factors for the increasing caesarean section rate in Southeast Brazil: a comparison of two birth cohorts, 1978-1979 and 1994

BACKGROUND

Brazil has the highest caesarean section (CS) rate in the world (36.4% in 1996).

METHODS

Risk factors for increasing CS rate were studied in two population-based cohorts of singleton live births in families residing in the municipality of Ribeirao Preto, State of Saõ Paulo, Southeast Brazil. The first comprised births from June 1978 to May 1979 (6750 births-one-year survey) and the second births from May to August 1994 (2846 births-4-month survey). Multiple unconditional logistic regression modelling was used to control for confounding.

RESULTS

The CS rate rose from 30.3% in 1978-1979 to 50.8% in 1994. In 1978-1979, socioeconomic, reproductive and demographic variables, and health service factors were associated with CS rate. In 1994, only reproductive, demographic and health service factors remained associated, e.g. hour of delivery (from 7 a.m. to 12 p.m.), attendance by the same physician for prenatal care and delivery, > or =4 prenatal visits, maternal age > or =30 years, 1-3 previous live births and birthweight 3500-3999 g.

CONCLUSION

Caesarean section in Brazil is widely performed for non-medical reasons in which physician convenience plays an important role. There is an urgent need for public health interventions to reduce the CS rate in Brazil, mainly directed towards cultural beliefs and physician behaviour.

Variation in physical fitness between ethnic groups in nine year olds

BACKGROUND

There is little information on cardio-respiratory fitness of children, especially in ethnic minorities in Britain. In this study we assess the associations of social factors, ethnicity, parental health related factors, child's anthropometry, blood pressure and cholesterol measurements with cardio-respiratory fitness.

METHODS

Power output against load at 85% of the maximum heart rate (PWC85%), was measured, using a cycle-ergometer test, in children aged 8-9 years in 22 randomly selected areas in England, 14 in Scotland and in 20 inner city areas in England. The subjects were 317 boys and 310 girls from the English sample, 152 boys and 140 girls from the Scottish sample and 242 boys and 261 girls from the inner city sample.

RESULTS

Short stature (P < 0.001), fatness (P < 0.001), and Indian subcontinent origin (OR = 0.34, 95% CI: 0.16, 0.68 in boys and OR = 0.22, 95% CI: 0.12, 0.40 in girls) were associated with inability to finish the test. In those who finished the test PWC85% was greater in taller children and in those with lower skinfold values (P < 0.001, except height in boys P = 0.017). The PWC85% in those originating in the Indian continent was lower (-0.17 watt/kg, 95% CI :-0.32, -0.01 in boys and -0.29, 95% CI: -0.43, -0.14 in girls) than in white children.

CONCLUSIONS

Shorter and obese children have poorer physical fitness than other children. Physical fitness is lower in children originating in the Indian subcontinent than other British children. This seems to be unrelated to socioeconomic disadvantage. Physical inactivity and lack of cycling skills may explain our findings.

Etiopathogenesis of isolated Robin sequence

OBJECTIVE

To investigate the etiopathogenesis of isolated Robin sequence.

DESIGN

A longitudinal and prospective study of children with isolated Robin sequence and no other associated syndromes or malformations.

SETTING

The study was carried out at the Hospital de Reabilitação de Anomalias Craniofaciais (formerly the Hospital for Research and Rehabilitation of Cleft Lip/Palate), University of São Paulo, Bauru, SP, Brazil, which provides care for patients with lip/palate lesions throughout Brazil.

PATIENTS

Forty-three children were initially included in the study, seven of whom were later found to be cases of Stickler syndrome and excluded. The remaining 36 children presenting only the anomaly triad of microretrognathia, glossoptosis, and cleft palate were followed up from the first month of life to 4 years of age with repetitive clinical and ophthalmological examination.

MAIN OUTCOME MEASURE

A family history of cleft lip/palate was determined on the basis of information provided by the parents and, when possible, the affected relative was submitted to physical examination.

RESULTS

A family history of cleft lip/palate was observed in 27.7% of cases, one case having a younger brother with only cleft palate but no microretrognathia or glossoptosis. Six cases of isolated cleft palate and three cases of cleft lip with or without cleft palate were present in distant relatives. Complete U-shaped cleft palate (wide cleft) was the most frequent type of cleft, which was present in 75% of cases. Only one case of incomplete cleft palate was observed, but U-shaped; 25% of the patients presented complete V-shaped cleft palate.

CONCLUSIONS

We conclude that heredity could be a factor in the etiopathogenesis of isolated Robin sequence and suggest that cleft palate (usually complete and U-shaped) is the primary event in the determination of the triad of anomalies.