Predicting poverty. Data mining approaches to the health and demographic surveillance system in Cuatro Santos, Nicaragua.

BACKGROUND: In order to further identify the needed interventions for continued poverty reduction in our study area Cuatro Santos, northern Nicaragua, we aimed to elucidate what predicts poverty, measured by the Unsatisfied Basic Need index. This analysis was done by using decision tree methodology applied to the Cuatro Santos health and demographic surveillance databases. METHODS: Using variables derived from the health and demographic surveillance update 2014, transferring individual data to the household level we used the decision tree framework Conditional Inference trees to predict the outcome "poverty" defined as two to four unsatisfied basic needs using the Unsatisfied Basic Need Index. We further validated the trees by applying Conditional random forest analyses in order to assess and rank the importance of predictors about their ability to explain the variation of the outcome "poverty." The majority of the Cuatro Santos households provided information and the included variables measured housing conditions, assets, and demographic experiences since the last update (5 yrs), earlier participation in interventions and food security during the last 4 weeks. RESULTS: Poverty was rare in households that have some assets and someone in the household that has a higher education than primary school. For these households participating in the intervention that installed piped water with water meter was most important, but also when excluding this variable, the resulting tree showed the same results. When assets were not taken into consideration, the importance of education was pronounced as a predictor for welfare. The results were further strengthened by the validation using Conditional random forest modeling showing the same variables being important as predicting the outcome in the CI tree analysis. As assets can be a result, rather than a predictor of more affluence our results in summary point specifically to the importance of education and participation in the water installation intervention as predictors for more affluence. CONCLUSION: Predictors of poverty are useful for directing interventions and in the Cuatro Santos area education seems most important to prioritize. Hopefully, the lessons learned can continue to develop the Cuatro Santos communities as well as development in similar poor rural settings around the world.

Effect of a food supplementation and psychosocial stimulation trial for severely malnourished children on the level of maternal depressive symptoms in Bangladesh.

BACKGROUND: Maternal depression is associated with poor child development and growth in low-income countries. This paper evaluates the effect of a community-based trial providing psychosocial stimulation and food supplements to severely malnourished children on maternal depressive symptoms in Bangladesh. METHODS: Severely underweight (weight-for-age Z-score < -3) hospitalized children aged 6-24 months (n = 507), were randomly assigned to: psychosocial stimulation (PS), food supplementation (FS), PS+FS, clinic control (CC) and hospital control (CH) at discharge. PS included play sessions with children and parental counselling to mothers during fortnightly follow-up visit at community clinics, conducted by trained play leaders for 6 months. FS involved cereal-based supplements (150-300 kcal/day) for 3 months. All groups received medical care, micronutrient supplements and growth monitoring. We used Bayley scales, Home Observation for Measurement of Environment (HOME) inventory and a parenting questionnaire to assess child development, home stimulation and mothers' child-rearing practices, respectively. We assessed mothers' depressive symptoms using a modified version of Centre for Epidemiologic Studies Depression Scale at baseline and at 6 months post intervention. RESULTS: Maternal depressive symptoms were significantly lower in the CH group at baseline (P = 0.014). After 6 months of intervention there was no significant effect of intervention after adjusting for baseline scores and all possible confounders. Maternal depressive symptoms were higher among poorer (P = 0.06), older (P = 0.057) and less educated (P = 0.019) mothers, who were housewives (P = 0.053), and whose husbands had more unstable jobs (P = 0.058). At 6 months post intervention, children's cognitive (P = 0.045) and motor (P = 0.075) development, HOME (P = 0.012) and mother's parenting score (P = 0.057) were higher among mothers with lower depressive symptoms. CONCLUSION: The study did not show a significant effect of the intervention on the level of maternal depressive symptoms. Interventions with higher intensity and/or of longer duration focusing directly on maternal psychosocial functioning are probably needed to reduce maternal depressive symptoms.

Survival of infants in the context of prevention of mother to child HIV transmission in South Africa.

AIM: We sought to study the survival of newborn children according to HIV status of the mother, that of the child and the timing of infection. METHODS: This is a prospective cohort study of 883 mothers (665 HIV-positive and 218 HIV-negative) and their infants. Data were collected using semi-structured questionnaires during home visits between the antenatal period and 36 weeks post-delivery. Infant HIV status was determined at 3, 24 and 36 weeks by HIV DNA PCR. RESULTS: The majority (81.3%) of infected infants who died were infected by 3 weeks of age. Of the HIV-exposed infants who died, 19 (28.4%) died before 6 weeks and 38 (56.7%) died by 12 weeks. The hazard ratio (HR) of mortality at 36 weeks of age in HIV-infected infants compared with exposed but negative infants was 8.9 (95% CI: 6.7-11.8). There was no significant difference in 36 week survival rates between HIV-non-exposed and HIV-exposed but negative infants (HR: 0.7; 95% CI: 0.3-1.5). The infant being HIV-positive at age 3 weeks (HR: 32 95% CI: 14.0-73.1) and rural site (HR: 4.4 95% CI: 1.2-23.4) were the two independent risk factors for infant death amongst HIV-exposed infants. CONCLUSION: The prognosis for infants with early HIV infection was very poor in this cohort. A greater focus on prevention of early infection, earlier screening for HIV infection and access to antiretrovirals for eligible infants is recommended.

Household food security is associated with early childhood language development: results from a longitudinal study in rural Bangladesh.

BACKGROUND: Although household food security (HHFS) has been linked to academic performance in school children, its association with early childhood development has received less attention, particularly in low-income countries. We investigated the association of HHFS with subsequent language development of children at 18 months of age in rural Bangladesh. METHODS: We followed 1439 infants born in 2002-2003 to the mothers in Maternal and Infant Nutrition Intervention in Matlab study, a large intervention trial conducted in rural Bangladesh. A HHFS scale was created from data collected from mothers during pregnancy. At 18 months, children's language (expression and comprehension) development was assessed using a Bengali adaptation of MacArthur's Communicative Development Inventory which was based on mothers' report of their children's ability to comprehend and express words in different categories. General linear regression models were used to examine the association between HHFS and language development at 18 months of age adjusting for potential confounders. RESULTS: Household food security was associated with language comprehension (B = 0.19, 95% CI = 0.09, 0.30, P < 0.001) and expression (B = 1.01, 95% CI = 1.00, 1.02, P < 0.01) at 18 months of age. Mean language comprehension and expression at 18 months of the children in higher quartiles of HHFS were higher (P < 0.05) than those of the children in lower quartiles. CONCLUSIONS: Household food security is positively associated with subsequent language development of rural Bangladeshi children. Early language development has been reported to predict later child development. Therefore, strategies to ensure HHFS status in Bangladesh and similar settings should be considered for optimum child development.

Early-life nutritional and environmental determinants of thymic size in infants born in rural Bangladesh.

AIM: The aim was to assess the impact of nutritional status and environmental exposures on infant thymic development in the rural Matlab region of Bangladesh. METHODS: In a cohort of N(max) 2094 infants born during a randomized study of combined interventions to improve maternal and infant health, thymic volume (thymic index, TI) was assessed by ultrasonography at birth and at 8, 24 and 52 weeks of age. Data on birth weight, infant anthropometry and feeding status were also collected. RESULTS: At all ages, TI was positively associated with infant weight and strongly associated with the month of measurement. Longer duration of exclusive breastfeeding resulted in a larger TI at 52 weeks. TI at birth and at 8 weeks correlated positively with birth weight, but by 24 and 52 weeks and when adjusted for infant weight this effect was no longer present. Thymic size was not affected by pre-natal maternal supplementation or by socioeconomic status but was correlated to arsenic exposure during pregnancy. CONCLUSION: In this population of rural Bangladeshi infants, thymic development is influenced by both nutritional and environmental exposures early in life. The long-term functional implications of these findings warrant further investigation.

Serum lipid values in adolescents are related to family history, infant feeding, and physical growth.

Total serum cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), apolipoprotein A-I (apo A-I), apolipoprotein B (apo B), and lipoprotein (a) (Lp(a)) were analysed in 879 14- and 17-year-old healthy adolescents (477 boys and 402 girls), and related to family history of cardiovascular disease, early feeding, weight and length at birth, and physical growth during infancy and childhood. Mean TC was significantly higher in girls than in boys (4.4 and 4.2 mmol/l, respectively, both age-groups together). High TC values ( > 5.2 mmol/l) were more prevalent in girls than in boys: 14% and 17% compared to 6% and 12% in 14- and 17-year-old girls and boys, respectively. Mean TC and LDL-C values were lower during mid-puberty in both boys and girls while, in boys but not in girls, mean HDL-C values decreased and TG values increased successively with increasing pubertal stage. Girls who were taking oral contraceptives had higher mean values of TC (4.91/4.39 mmol/l), TG (1.32/0.83 mmol/l), and apo B (0.89/0.73 g/l). Boys with a family history of early deaths ( < 55 years) from myocardial infarction and girls with a family history of cerebral haemorrhage/thrombosis in fathers had higher mean values of TC (4.55/4.17 and 5.03/4.40 mmol/l, for boys and girls, respectively), LDL-C (2.84/2.47 and 3.08/2.56 mmol/l), and apo B (0.73/0.70 and 0.86/0.73 g/l). Adolescents with short duration of breast feeding ( < 6 months), or early introduction of infant formula, had higher mean values of TC (4.29/4.14 mmol/l) and apo B (0.72/0.68 g/l). There were no significant correlations between serum lipid values and body weight or length at birth, but adolescents with high LDL-C (upper quartile) seemed to have lower attained heights during infancy and childhood. In conclusion, this study shows that serum lipids in adolescence are primarily related to age and sex but also to early determinants like family history of cardiovascular diseases, infant feeding, and early physical growth.

Growth of breast-fed infants deviates from current reference data: a pooled analysis of US, Canadian, and European data sets. World Health Organization Working Group on Infant Growth.

OBJECTIVE: To compare growth patterns of a large sample of breast-fed infants with the current World Health Organization (WHO)/Centers for Disease Control and Prevention (CDC) reference data. METHODS: Data from seven longitudinal studies of infant growth in North America and northern Europe were pooled (n = 453 breast-fed infants). Weight, length and head circumference were compared with the WHO/CDC reference, and repeated-measures analysis of variance was used to examine associations between growth patterns and breast-feeding duration, age of introduction of solid foods, and use of other milks. RESULTS: In comparison with WHO/CDC reference data, infants breast-fed for at least 12 months (n = 226) grew more rapidly in the first 2 months and less rapidly (particularly in weight) from 3 to 12 months; the mean z score at 12 months was -0.53 for weight for age, -0.29 for length for age, and -0.32 for weight for length. In contrast, mean head circumference was well above the WHO/CDC median throughout the first year of life. These patterns were generally consistent across studies. In the full sample (n = 453), a longer duration of breast-feeding was associated with a greater decline in weight for age and weight for length but not length for age. CONCLUSION: These results suggest that if growth charts are to reflect patterns consistent with those of infants following WHO feeding recommendations, new reference data based on breast-fed infants are needed.

Measuring children's diets: evaluation of dietary assessment techniques in infancy and childhood.

Epidemiological studies of dietary habits in infancy and childhood face a number of difficulties, which are more or less specific for these ages. In connection with studies on dietary habits of Swedish infants and children an evaluation of different dietary assessment techniques was performed. Breastfeeding data obtained in retrospective interviews at six months had good validity. The reliability of breastfeeding and weaning data decreased over time. Short questions on food frequencies, often used in research and clinical practice, were shown to be a poor screening instrument and suffered from biases when used in groups of four- and eight-year-old children. Group mean estimations of dietary intake of four- and eight-year-old children obtained by 24-hour recalls were close to those of seven-day records from the same individuals. Dietary intake in a 13-year-old group according to 24-hour recall and dietary history differed significantly; the dietary history gave much higher estimations. The reliability of dietary history in a small group of 13-year-old boarding school children was fairly good. The internal validity of food recording was examined by use of chemical analysis of duplicate portions. Generally, there was good agreement between the records and the analysed duplicates. The intake of a number of nutrients varied during the week, often showing a maximum towards the weekend. The intake of vitamin C was higher in winter time, otherwise no seasonal variation was found. The intra-individual variation in dietary intake is illustrated and its consequences for dietary studies are discussed.

Changing social patterns of risk factors for cardiovascular disease in a Swedish community intervention programme.

Since 1985 a small-scale community-based cardiovascular disease (CVD) preventive programme has been in operation in an inland municipality, Norsjö, in Northern Sweden. The aim of this study was to assess the development of the relationship between social position and CVD risk factors in repeated cross-sectional surveys (1985-1990) among all men and women aged 30, 40, 50 and 60 years in the study area, using an age-stratified random sample from the Northern Sweden MONICA Study of 1986 and 1990 as reference population. These multiple cross-sectional surveys comprised a self-administered questionnaire and a health examination. Of the study population 95% (n = 1499) and 80% of those in the reference area (n = 3208) participated. Subjects were classified with regard to demographic, structural and social characteristics in relation to CVD risk factors and self-reported health status. Time trends in classical risk factor occurrence were assessed in terms of age- and sex- adjusted odds ratios using Mantel-Haenszel procedures. When simultaneously adjusting for several potential confounders we used a logistic regression analysis. Initially, more than half of the study population, both males and females, had and elevated (> or = 6.5 mmol/l) serum cholesterol level. After adjustments had been made for age and social factors it was found that the relative risk of hypercholesterolaemia dropped substantially and significantly among both sexes during the 6 years of CVD intervention in the study area. However, the probability of being a smoker was significantly reduced only in highly educated groups. Among other risk factors no single statistically significant change over time could be found. In the reference area there were no changes over time for the selected CVD risk factors. People in the study area had a less favourable perception of their health than those in the reference area. Social differences were found when perceived good health was measured, especially in variables indicating emotional and social support. When sex, age and social factors had been accounted for there was not clear change over the years in perceived good health.

Dietary determinants of a non-progressive spastic paraparesis (Konzo): a case-referent study in a high incidence area of Zaire.

BACKGROUND: Konzo is an upper motor neuron disease in Africa, characterized by an abrupt onset of a permanent but non-progressive spastic paraparesis. It is named after the local designation in the first report from Zaire. Konzo has been attributed to a metabolic insult from the combined effect of high cyanide and low sulphur intake from several weeks of exclusive consumption of insufficiently processed bitter cassava roots. METHODS: The association between insufficient soaking of cassava roots and konzo is assessed in a matched case-referent study with multivariate conditional logistic regression including 57 case-referent pairs from a rural high incidence community of Zaire. RESULTS: In the multivariate analysis short processing of cassava in the form of only 2 nights soaking yielded an odds ratio of 11.0 (95% confidence interval 1.7-73) when controlling for poverty-related factors and diet. We also show a dose-response relationship for insufficient cassava soaking, both unadjusted and adjusted for potential confounders. CONCLUSIONS: This study supports a causal relationship between insufficient processing of bitter cassava and konzo.

Insulin resistance syndrome in adolescents.

To explore whether the so-called insulin resistance syndrome can be identified in adolescents, serum insulin level was measured in 842 healthy Swedish adolescents (462 boys and 380 girls) and the values were related to current serum lipoprotein and apolipoprotein values (triglyceride [TG], total cholesterol [TC], high-density lipoprotein cholesterol [HDL-C), low-density lipoprotein cholesterol [LDL-C], apolipoprotein [apo] A-I, apo B, and lipoprotein(a)), blood pressure (BP), and anthropometric measurements and previous physical growth. Mean serum insulin values were higher in 14-year-olds as compared with 17-year-olds and were highest in midpuberty. Adolescents with a high serum insulin had a higher attained height and weight during infancy and childhood. Obesity (body mass index [BMI] > 30 kg/m2) was found in 1% of both boys and girls, and hypertensive BP levels were found in 3% of the boys and 1% of the girls. Controlling for age, serum insulin correlated positively with BMI (r = .36 and .25 in boys and girls, respectively), TG (r = .32 and .14), LDL-C (r = .17 and .24), and apoB (r = .23 and .23) and negatively with HDL-C (r = -.13 and -.21). High serum insulin, TG, LDL-C, and BP and low HDL-C clustered in adolescents with high BMI. In conclusion, the findings of this study indicate that features typical of the insulin resistance syndrome are already present in adolescents.

Children born in the summer have increased risk for coeliac disease.

STUDY OBJECTIVE: Coeliac disease, also called permanent gluten sensitive enteropathy, is being recognised as a widespread health problem. Defining the possible role of environmental factors in its aetiology might open doors to primary prevention. This study therefore analysed if the risk for coeliac disease varies with month of birth as a proxy for a seasonal pattern for possible causal environmental exposure(s). DESIGN: A population based incidence register of coeliac disease in children below 15 years of age covering the period from 1973 to 1997. Incidence rates were calculated by month of birth, stratified for age at diagnosis. Poisson regression analyses were used to estimate the relative risk for coeliac disease for children below 2 years of age by season of birth, also taking into account gender and time period of diagnosis. SETTING: Sweden. PARTICIPANTS: All 2151 children in the study base with verified coeliac disease. MAIN RESULTS: The risk for coeliac disease was significantly higher if born during the summer as compared with the winter (RR=1.4, 95% CI 1.2 to 1.7), but only in children below 2 years of age at diagnosis. This relative seasonal risk pattern prevailed during a 10 year epidemic of coeliac disease, although incidence rates varied threefold. The incidence was constantly higher among girls as compared with boys, but boys showed a more pronounced seasonal variation in risk than girls. CONCLUSIONS: An increased coeliac disease risk in children born in the summer compared with the winter reflects causal environmental exposure(s) with a seasonal pattern. Infections might be the exposure of importance, either by means of a direct causal role and/or through interaction with other exposures, for example, gluten intake. However, non-infectious exposures should also be explored as possible contributing causal factors.

Fertility and infant mortality trends in Nicaragua 1964-1993. The role of women's education.

OBJECTIVES: To assess trends in fertility and infant mortality rates (IMR) in León, Nicaragua, and to examine the effect of women's education on these trends during 1964-1993, a period of rapid social change. DESIGN: Cross sectional survey, based on random cluster sampling. A retrospective questionnaire on reproductive events was used. SETTING: The municipality of León, which is the second largest city in Nicaragua, with a total population of 195,000 inhabitants. SUBJECTS: 10,867 women aged 15-49 years, corresponding to 176,281 person years of reproductive life. Their children contributed 22,899 person years under 12 months of age to the IMR analysis. MAIN OUTCOME MEASURES: Fertility rate (number of pregnancies per 1000 person years) for specific age groups and calendar periods, total fertility rate, and IMR. RESULTS: Fertility rates and IMR declined in parallel, especially during the 1980s. However, education specific fertility rates did not decline, but the proportion of educated young women increased from 20% to 46%. This had also an impact on the overall IMR decline, although IMR reduction mainly took place among infants of women without formal education, decreasing from 118 to 69 per 1000 during the observation period. CONCLUSIONS: In this demographic transition over three decades, fertility and IMR declined simultaneously. The decreasing trend in fertility was mainly explained by an increase in women's education, while the IMR decline seemed to be the result of health interventions, specially targeted to poorer groups of women and their infants. Thus, social differences in fertility rates remained unchanged, while equity in chances of child survival increased.

Utilisation of reproductive health services in rural Vietnam; are there equal opportunities to plan and protect pregnancies?

STUDY OBJECTIVES: To describe the utilisation of reproductive health services (family planning, antenatal care, and delivery services) and the socioeconomic determinants for utilisation of health services. DESIGN: This was a cross sectional survey, using a multistage sampling technique. SETTING: Tien Hai district, Thai Binh Province, Vietnam. Altogether 1132 mothers with children under 5 years of age were interviewed about antenatal, delivery, and family planning services utilisation during a five year period (1987-92). MAIN RESULTS: Seventy per cent of the women used contraceptive methods, with the intrauterine device being the most common. The use of the intrauterine device was positively associated with the number of children alive but not with other sociodemographic factors in the mothers. Thirty per cent of the women had attended an antenatal clinic for check ups during their last pregnancy. It was found that mothers with fewer deliveries, higher education, and who were Buddhist or of no religion had utilised antenatal services more frequently than the others. Seventy five per cent of the mothers in this study had been assisted by health professionals at their last delivery. Those mothers with fewer deliveries, higher education, who were Buddhist or had no religion, and had sufficient to eat were more likely to have their births attended by health professionals. CONCLUSIONS: In spite of a relatively high education level in the population and services which are generally available, there was an under utilisation of antenatal and delivery care and there was no equal opportunity for different groups of mothers to use these services. Family planning services were, however, frequently used and were used to the same extent by different groups of mothers. Except for abortion, alternatives to the intrauterine device method were rarely available. If pregnancies are to be protected in an efficient way in rural Vietnam, reproductive health care must be strengthened and efforts should be made to reach the women who are not using these services at present.

Neural spread of herpes simplex virus types 1 and 2 in mice after corneal or subcutaneous (footpad) inoculation.

Twelve herpes simplex virus (HSV) strains, 6 of each type, were inoculated subcutaneously into the left hind foot and into the cornea of the right eye of 12-day-old Swiss albino mice. The neural spread of virus to trigeminal and spinal ganglia and to brain and spinal cord was studied by demonstration of infective virus, histology and electron microscopy. Type 1 and type 2 infections seemed to spread equally well by intra-axonal transport. Using a protein tracer (horseradish peroxidase) injected into the same site as the virus, transport of the tracer to neurons corresponding to those infected with virus was observed. The extensive destruction of CNS tissue in the transitional region of the trigeminal root where CNS and the peripheral nervous system meet is discussed with reference to the pathogenesis of HSV encephalitis.

Excess female mortality in rural Somalia--is inequality in the household a risk factor?

Gender differences in mortality risks in rural Somali communities were studied to assess their relation to literacy, marital status and family economy between January 1987 and December 1989. In all, 6947 person-years form the basis for the demographic analysis and estimations of mortality rates and survival. Both sexes showed similar mortality risks in infancy and early childhood, but females demonstrated a greater risk of dying during their reproductive life than males. Respiratory symptoms, diarrhoea, fever and jaundice dominated the symptoms prior to death Illiteracy in women considerably increased the risk of dying from 15 years and onwards particularly when living with literate men. The life expectancy from 15 years was 58 for a literate male but only 42 years for an illiterate woman living with a literate head of household. Multivariate analyses showed after adjustment for marital status and literacy that an excess female mortality from 15 years, but especially from 45 years, was associated to a household situation, where the woman did not subside on farming but on other, mainly commercial, activities. This vulnerability of females was associated to the recession of the economy in the pre-war situation in Somalia, a backlash hitting women trying to earn their living. To conclude, gender differences in a number of factors in the household-literacy, marital status and especially source of income-were disadvantageous for the women, increasing the mortality risk in this setting.

Contraceptive patterns among women and men in León, Nicaragua.

The aim was to study the contraceptive patterns among men and women in León, Nicaragua. A questionnaire about sexual, contraceptive, reproductive and socioeconomic issues was directed to 7,789 households including 22% of all women of the municipality aged 15-49 years (n = 10,867). A subsample of 388 men and 413 women aged 15-49 years was drawn at random. Refusals were less than 2%. Private interviews revealed that among fertile women who had been sexually active within the last three months, non-pregnant and wishing to avoid pregnancy, 77% were contracepting. Female sterilization was the most common contraceptive method (39%), followed by intrauterine device (16%). Even though around 60% of women at some time had tried oral contraceptives, only 13% of contraceptors used them currently. The rhythm and interruption methods together constituted only 4%. Condom use was low and mainly occasional. Contraceptive use in sexually active women aged 15-44 years was lower among those having lower education, living in rural areas, and living under poverty conditions. The predominance of female sterilization and the occasional condom use-mainly reported by men-reflects a situation of relative male control over contraception and reproduction. This probably originates from "machista" values where men having many children with different women are considered strong. There was also a significantly higher use of contraceptives among the better-off women and men compared with the extremely poor. The situation of many poor women, in a country with limited contraceptive services, is worrying considering that abortion is illegal and the threat of HIV epidemic is growing. The situation for adolescents is particularly problematic with low experience in contraceptive use.

Coeliac disease: effect of early feeding on the incidence of the disease.

Coeliac disease, also called permanent gluten sensitive enteropathy, has recently been recognised as constituting a widespread health problem. Effective treatment involves the strict exclusion of wheat, rye, barley and possibly also oats from the diet. Genetic susceptibility and the presence of gluten in the diet are prerequisites for developing the disease. Sweden has recently experienced an epidemic of coeliac disease in children below 2 years of age. Previously, considerable changes in incidence over time have also been reported from England, Scotland and Ireland. Such obvious changes in incidence over rather short time periods, in genetically stable populations, emphasise the importance of environmental factors in the aetiology. Thus, most likely, the aetiology of coeliac disease is multifactorial. However, further conclusive evidence is required to settle if environmental factors, beyond presence of gluten in the diet, really influence the immunological process resulting in the coeliac small intestinal lesion, or merely influence the clinical expression of the disease. The search for contributing exposures has thus far focused on early feeding, suggesting that breast-feeding duration and the amount of gluten consumed are of importance, and possibly also the age for introducing gluten into the diet of infants. The pattern of causation may vary over time and between countries, however, which may obscure the search for risk factors. Nevertheless, a challenging possibility that needs to be explored is if coeliac disease can be delayed, or possibly even prevented for an entire life span, by favourable dietary habits.

Gender and social differences in adolescent sexuality and reproduction in Nicaragua.

PURPOSE: The aim of this research was to study gender and social differences in adolescent sexuality and reproduction, as reflected in age at first intercourse and age at first pregnancy, as a basis for future interventions in the municipality of León, Nicaragua. METHODS: In a community-based cross-sectional study including 7789 households, all women aged 15-49 years (n = 10,867) were interviewed about socioeconomic, sexual, and reproductive issues. A random subsample of men (n = 388) and women (n = 413) aged 15-49 years was interviewed in more detail about sexual patterns and reproduction. RESULTS: The median age at first intercourse for women and men was 17.8 and 16.2 years, respectively. Women's average latency period to end of first pregnancy was 22 months. There was a significant tendency to start active sexual life later among today's girls aged 15-20 years, compared to the groups 21-27, 28-35, and 36-49 years old. A similar trend was found in age at first pregnancy. These secular trends were not found among men. Age at first pregnancy for current adolescents was lower among those having less formal education. CONCLUSIONS: The short latency period between first sexual intercourse and end of first pregnancy, probably reflecting lack of access to counseling and contraception, is worrying in light of the growing sexually transmitted disease/human immunodeficiency virus threat. The secular trend of later start of reproduction, however, is a positive sign which partly may be an effect of increasing education in the Nicaraguan society.

PIP: This study sought to uncover gender and social differences in adolescent sexuality and reproduction in Nicaragua through an investigation of age at first coitus and first pregnancy. Data were gathered through a 1993 cross-sectional, community-based survey of a representative sample of 7789 households in the municipality of Leon. Interviews were held with 10,867 women aged 15-49, and more detailed information was elicited from a random subsample of 388 men and 413 women. It was found that median age at first coitus was 17.8 for women and 16.2 for men, with 25% of the population engaging in coitus before age 15. Women delivered their first child at a median age of 19.6 years, whereas men became fathers at 21.2 years. Lack of formal education increased risk of earlier pregnancy for women by 2.5 times, but no increased risk occurred for rural versus urban residence. Earlier pregnancy occurred in women who did not live with their biological fathers during childhood and adolescence (living with a stepfather increased risk of early coitus and delivery even more). Men without a formal education became fathers at an earlier age in both urban and rural areas. The period between first coitus and delivery for women was 21.5 months (20 months for women with primary education or less and 27 months for those who completed ninth-grader or higher). Age groups comparisons (15-20, 21-27, 28-35, and 36-49) showed that the current adolescents were experiencing first coitus and first pregnancy significantly later than the older groups but that the 28-35 age group showed significantly earlier onset of each event. These results point to the need to improve gender equity and women's status and to develop a health care policy that responds to the special needs of adolescents (counseling, access to contraceptives, and availability of safe abortion). Sex education programs must begin at the primary levels in schools because of high drop-out rates.

Does breast-feeding affect the risk for coeliac disease?

Coeliac disease, or permanent gluten sensitive enteropathy, has emerged as a widespread health problem. It is considered an immunological disease, possibly of autoimmune type, albeit strictly dependent on the presence in the diet of wheat gluten and similar proteins from rye and barley. There are reasons to believe that the aetiology of coeliac disease is multifactorial, i.e. that other environmental exposures than the mere presence in the diet of gluten affect the disease process. Our studies have shown that prolonged breast-feeding, or perhaps even more important, ongoing breast-feeding during the period when gluten-containing foods are introduced into the diet, reduce the risk for coeliac disease. The amount of gluten consumed is also of importance in as much as larger amounts of gluten-containing foods increase the risk for coeliac disease, while it still is uncertain if the age for introducing gluten into the diet of infants is important. Thus, a challenging possibility, that need to be further explored, is if the coeliac enteropathy can be postponed, or possibly even prevented for the entire life span, by favourable dietary habits early in life.