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1.
Matern Child Nutr ; 17(2): e13106, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33236840

RESUMO

This study in Burkina Faso investigated whether offspring of young mothers who had received weekly periconceptional iron supplementation in a randomised controlled trial were at increased risk of malaria. A child safety survey was undertaken in the peak month of malaria transmission towards the end of the trial to assess child iron biomarkers, nutritional status, anaemia and malaria outcomes. Antenatal iron biomarkers, preterm birth, fetal growth restriction and placental pathology for malaria and chorioamnionitis were assessed. Data were available for 180 babies surviving to the time of the survey when their median age was 9 months. Prevalence of maternal iron deficiency in the last trimester based on low body iron stores was 16%. Prevalence of active placental malaria infection was 24.8%, past infection 59% and chorioamnionitis 55.6%. Babies of iron supplemented women had lower median gestational age. Four out of five children ≥ 6 months were iron deficient, and 98% were anaemic. At 4 months malaria prevalence was 45%. Child iron biomarkers, anaemia and malaria outcomes did not differ by trial arm. Factors associated with childhood parasitaemia were third trimester C-reactive protein level (OR 2.1; 95% CI 1.1-3.9), active placental malaria (OR 5.8; 1.0-32.5, P = 0.042) and child body iron stores (OR 1.13; 1.04-1.23, P = 0.002). Chorioamnionitis was associated with reduced risk of child parasitaemia (OR 0.4; 0.1-1.0, P = 0.038). Periconceptional iron supplementation of young women did not alter body iron stores of their children. Higher child body iron stores and placental malaria increased risk of childhood parasitaemia.


Assuntos
Malária , Nascimento Prematuro , Burkina Faso , Criança , Pré-Escolar , Suplementos Nutricionais , Feminino , Ácido Fólico , Humanos , Lactente , Recém-Nascido , Ferro , Malária/epidemiologia , Malária/prevenção & controle , Placenta , Gravidez
2.
Clin Nutr ; 39(1): 204-214, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30737046

RESUMO

BACKGROUND & AIMS: Low iron stores may protect from malaria infection, therefore improving iron stores in early pregnancy in line with current recommendations could increase malaria susceptibility. To test this hypothesis we compared iron biomarkers and red cell indices in nulliparae and primigravidae who participated in a randomized controlled trial of long-term weekly iron supplementation. METHODS: Cross-sectional and longitudinal data analysis from a randomized controlled trial of long-term weekly iron supplementation in rural Burkina Faso. Malaria parasitaemia was monitored and biomarkers and red cell indices measured at study end-points: plasma ferritin, transferrin receptor (sTfR), zinc protoporphyrin, hepcidin, sTfR/log10 ferritin ratio, body iron, haemoglobin, red cell distribution width; mean corpuscular haemoglobin concentration/volume, and C-reactive protein. Correlation coefficients between biomarkers and red cell indices were determined. A regression correction approach based on ferritin was used to estimate iron body stores, allowing for inflammation. Body iron differences were compared between nulliparae and primigravidae, and the association determined of iron biomarkers and body iron stores with malaria. RESULTS: Iron and haematological indices of 972 nulliparae (mean age 16.5 years) and 314 primigravidae (median gestation 18 weeks) were available. Malaria prevalence was 54.0% in primigravidae and 41.8% in nulliparae (relative risk 1.28, 95% CI 1.13-1.45, P < 0.001), anaemia prevalence 69.7% and 43.4% (P < 0.001), and iron deficient erythropoiesis (low body iron) 8.0% and 11.7% (P = 0.088) respectively. Unlike other biomarkers the sTfR/log10 ferritin ratio showed no correlation with inflammation as measured by CRP. Most biomarkers indicated reduced iron deficiency in early pregnancy, with the exception of haemoglobin. Body iron increased by 0.6-1.2 mg/kg in early gestation, did not differ by malaria status in nulliparae, but was higher in primigravidae with malaria (6.5 mg/kg versus 5.0 mg/kg; relative risk 1.53, 95% CI 0.67-2.38, P < 0.001). CONCLUSION: In primigravidae, early pregnancy haemoglobin was not a good indicator of requirement for iron supplementation, which could be detrimental given the association of better iron status with increased malaria infection. TRIAL REGISTRATION: clinicaltrials.gov:NCT01210040. Until placed in a public repository, data relating to the current study can be requested from the corresponding author and will be made available following an end user data agreement and sponsor approval.


Assuntos
Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Ferro/sangue , Malária/sangue , Malária/epidemiologia , Adolescente , Adulto , Biomarcadores , Burkina Faso/epidemiologia , Estudos Transversais , Feminino , Número de Gestações , Humanos , Estudos Longitudinais , Gravidez , Primeiro Trimestre da Gravidez , Prevalência , Adulto Jovem
3.
J Clin Pathol ; 67(8): 717-23, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24915849

RESUMO

AIM: Iron deficiency is an important child health problem. Its diagnosis in areas of high infection exposure remains complicated as inflammation may interfere with the accuracy of peripheral iron markers. With this study, we aimed to validate the conventional iron markers and two novel iron markers, hepcidin and Red blood cell Size Factor (RSf), against the reference standard of iron status, bone marrow iron, in children living in an infectious setting. METHODS: We compared ferritin, soluble transferrin receptor, Soluble Transferrin Log-Ferritin Index (sTfR-F), mean cellular volume, mean cellular haemoglobin concentration, hepcidin and RSf, against bone marrow iron in 87 healthy Malawian children (6-66 months) scheduled for elective surgery. RESULTS: Of all children, 44.8% had depleted bone marrow iron stores. Using optimised cut-offs, ferritin (<18 µg/L) and sTfR-F (>1.85) best predicted depleted iron stores with a sensitivity/specificity of 73.7%/77.1% and 72.5%/75.0%, respectively. Hepcidin (<1.4 nmol/L) was a moderate sensitive marker (73.0%) although specificity was 54.2%; RSf poorly predicted depleted iron stores. CONCLUSIONS: We provide the first bone marrow-validated data on peripheral iron markers in African children, and showed ferritin and sTfR-F best predicted iron status. Using appropriately defined cut-offs, these indicators can be applied in surveillance and research. As their accuracy is limited for clinical purposes, more reliable iron biomarkers are still required in African children.


Assuntos
Anemia Ferropriva/diagnóstico , Medula Óssea/química , Hepcidinas/sangue , Ferro/análise , Anemia Ferropriva/sangue , Biomarcadores/sangue , Pré-Escolar , Índices de Eritrócitos , Feminino , Ferritinas/sangue , Humanos , Lactente , Ferro/sangue , Deficiências de Ferro , Malaui , Masculino , Receptores da Transferrina/sangue , Transferrina
4.
PLoS One ; 8(12): e78964, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24339866

RESUMO

INTRODUCTION: A reliable diagnostic biomarker of iron status is required for severely anemic children living in malarious areas because presumptive treatment with iron may increase their infection risk if they are not iron deficient. Current biomarkers are limited because they are altered by host inflammation. In this study hepcidin concentrations were assessed in severely anemic children living in a highly malarious area of Malawi and evaluated against bone marrow iron in order to determine the usefulness of hepcidin as a point of care test. METHODS: 207 severely anemic children were assessed for levels of hepcidin, ferritin, serum transferrin receptor, erythropoietin, hematological indices, C-reactive protein, interleukin-6, malaria parasites and HIV infection. Deficiency of bone marrow iron stores was graded and erythroblast iron incorporation estimated. Interaction of covariates was assessed by structural-equation-modeling. RESULTS AND CONCLUSION: Hepcidin was a poor predictor of bone marrow iron deficiency (sensitivity 66.7%; specificity 48.5%), and of iron incorporation (sensitivity 54.2%; specificity 61.8%), and therefore would have limitations as a point of care test in this category of children. As upregulation of hepcidin by inflammation and iron status was blunted by erythropoietin in this population, enhanced iron absorption through the low hepcidin values may increase infection risk. Current recommendations to treat all severely anemic children living in malarious areas with iron should therefore be reconsidered.


Assuntos
Anemia/sangue , Anemia/epidemiologia , Medula Óssea/metabolismo , Doenças Transmissíveis/sangue , Doenças Transmissíveis/epidemiologia , Hepcidinas/sangue , Deficiências de Ferro , Pré-Escolar , Eritropoese , Feminino , Humanos , Hipóxia/sangue , Incidência , Lactente , Malaui/epidemiologia , Masculino , Análise Multivariada
5.
Nutr Rev ; 71(8): 528-40, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23865798

RESUMO

Infection is a major cause of neonatal death in developing countries. This review investigates whether host iron status affects the risk of maternal and/or neonatal infection, potentially contributing to neonatal death, and summarizes the iron acquisition mechanisms described for pathogens causing stillbirth, preterm birth, and congenital infection. In vitro evidence shows that iron availability influences the severity and chronicity of infections that cause these negative outcomes of pregnancy. In vivo evidence is lacking, as relevant studies of maternal iron supplementation have not assessed the effect of iron status on the risk of maternal and/or neonatal infection. Reducing iron-deficiency anemia among women is beneficial and should improve the iron stores of babies; moreover, there is evidence that iron status in young children predicts the risk of malaria and, possibly, the risk of invasive bacterial diseases. Caution with maternal iron supplementation is indicated in iron-replete women who may be at high risk of exposure to infection, although distinguishing between iron-replete and iron-deficient women is currently difficult in developing countries, where a point-of-care test is needed. Further research is indicated to investigate the risk of infection relative to iron status in mothers and babies in order to avoid iron intervention strategies that may result in detrimental birth outcomes in some groups of women.


Assuntos
Nível de Saúde , Mortalidade Infantil , Infecções/epidemiologia , Ferro/sangue , Complicações Infecciosas na Gravidez/epidemiologia , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/prevenção & controle , Países em Desenvolvimento/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Resultado da Gravidez , Nascimento Prematuro , Fatores de Risco
6.
PLoS One ; 7(8): e42670, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22916146

RESUMO

INTRODUCTION: Iron deficiency is highly prevalent in pre-school children in developing countries and an important health problem in sub-Saharan Africa. A debate exists on the possible protective effect of iron deficiency against malaria and other infections; yet consensus is lacking due to limited data. Recent studies have focused on the risks of iron supplementation but the effect of an individual's iron status on malaria risk remains unclear. Studies of iron status in areas with a high burden of infections often are exposed to bias. The aim of this study was to assess the predictive value of baseline iron status for malaria risk explicitly taking potential biases into account. METHODS AND MATERIALS: We prospectively assessed the relationship between baseline iron deficiency (serum ferritin <30 µg/L) and malaria risk in a cohort of 727 Malawian preschool children during a year of follow-up. Data were analyzed using marginal structural Cox regression models and confounders were selected using causal graph theory. Sensitivity of results to bias resulting from misclassification of iron status by concurrent inflammation and to bias from unmeasured confounding were assessed using modern causal inference methods. RESULTS AND CONCLUSIONS: The overall incidence of malaria parasitemia and clinical malaria was 1.9 (95% CI 1.8-2.0) and 0.7 (95% CI 0.6-0.8) events per person-year, respectively. Children with iron deficiency at baseline had a lower incidence of malaria parasitemia and clinical malaria during a year of follow-up; adjusted hazard ratio's 0.55 (95%-CI:0.41-0.74) and 0.49 (95%-CI:0.33-0.73), respectively. Our results suggest that iron deficiency protects against malaria parasitemia and clinical malaria in young children. Therefore the clinical importance of treating iron deficiency in a pre-school child should be weighed carefully against potential harms. In malaria endemic areas treatment of iron deficiency in children requires sustained prevention of malaria.


Assuntos
Ferro/sangue , Malária/epidemiologia , Pré-Escolar , Fatores de Confusão Epidemiológicos , Feminino , Humanos , Incidência , Lactente , Malária/sangue , Malaui/epidemiologia , Masculino , Estudos Prospectivos
7.
BMC Med Res Methodol ; 12: 53, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22520150

RESUMO

BACKGROUND: Compliance is a critical issue for parental questionnaires in school based epidemiological surveys and high compliance is difficult to achieve. The objective of this study was to determine trends and factors associated with parental questionnaire compliance during respiratory health surveys of school children in Merseyside between 1991 and 2006. METHODS: Four cross-sectional respiratory health surveys employing a core questionnaire and methodology were conducted in 1991, 1993, 1998 and 2006 among 5-11 year old children in the same 10 schools in Bootle and 5 schools in Wallasey, Merseyside. Parental compliance fell sequentially in consecutive surveys. This analysis aimed to determine the association of questionnaire compliance with variation in response rates to specific questions across surveys, and the demographic profiles for parents of children attending participant schools. RESULTS: Parental questionnaire compliance was 92% (1872/2035) in 1991, 87.4% (3746/4288) in 1993, 78.1% (1964/2514) in 1998 and 30.3% (1074/3540) in 2006. The trend to lower compliance in later surveys was consistent across all surveyed schools. Townsend score estimations of socio-economic status did not differ between schools with high or low questionnaire compliance and were comparable across the four surveys with only small differences between responders and non-responders to specific core questions. Respiratory symptom questions were mostly well answered with fewer than 15% of non-responders across all surveys. There were significant differences between mean child age, maternal and paternal smoking prevalence, and maternal employment between the four surveys (all p < 0.01). Out-migration did not differ between surveys (p = 0.256) with three quarters of parents resident for at least 3 years in the survey areas. CONCLUSION: Methodological differences or changes in socio-economic status of respondents between surveys were unlikely to explain compliance differences. Changes in maternal employment patterns may have been contributory. This analysis demonstrates a major shift in community parental questionnaire compliance over a 15 year period to 2006. Parental questionnaire compliance must be factored into survey designs and methodologies.


Assuntos
Proteção da Criança/estatística & dados numéricos , Participação da Comunidade/psicologia , Fidelidade a Diretrizes , Indicadores Básicos de Saúde , Inquéritos Epidemiológicos , Pais/psicologia , Adolescente , Adulto , Antropometria , Asma/complicações , Asma/diagnóstico , Asma/epidemiologia , Viés , Área Programática de Saúde/estatística & dados numéricos , Distribuição de Qui-Quadrado , Criança , Proteção da Criança/tendências , Participação da Comunidade/estatística & dados numéricos , Participação da Comunidade/tendências , Estudos Transversais , Inglaterra/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/prevenção & controle , Feminino , Inquéritos Epidemiológicos/estatística & dados numéricos , Humanos , Masculino , Comportamento Materno , Gravidez , Prevalência , Sons Respiratórios/diagnóstico , Fatores de Risco , Instituições Acadêmicas/estatística & dados numéricos , Fumar/epidemiologia , Fumar/psicologia , Fatores Socioeconômicos , Inquéritos e Questionários
8.
Pediatr Blood Cancer ; 59(2): 211-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22492631

RESUMO

Patients with Sickle cell disease (SCD) exhibit signs of poor growth, increased susceptibility to infection and recurrent episodes of painful vaso-occlusive crises. Micronutrient deficiencies may increase susceptibility to these outcomes. We conducted a systematic review to assess the strength of evidence for improved outcomes related to micronutrient interventions. Six randomized-controlled trials of moderate quality met the inclusion criteria. Zinc supplementation was associated with improved growth and decreased incidence of infection and is a promising intervention in the management of SCD patients. Omega-3 fatty acid supplementation was associated with limited reduction in vaso occlusive crises. This review identifies key knowledge gaps, which are important research priorities for nutritional interventions.


Assuntos
Anemia Falciforme/complicações , Anemia Falciforme/patologia , Arteriopatias Oclusivas/etiologia , Infecções/etiologia , Micronutrientes/deficiência , Humanos
9.
PLoS Negl Trop Dis ; 6(3): e1555, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22514750

RESUMO

BACKGROUND: Hookworm infections are an important cause of (severe) anemia and iron deficiency in children in the tropics. Type of hookworm species (Ancylostoma duodenale or Necator americanus) and infection load are considered associated with disease burden, although these parameters are rarely assessed due to limitations of currently used diagnostic methods. Using multiplex real-time PCR, we evaluated hookworm species-specific prevalence, infection load and their contribution towards severe anemia and iron deficiency in pre-school children in Malawi. METHODOLOGY AND FINDINGS: A. duodenale and N. americanus DNA loads were determined in 830 fecal samples of pre-school children participating in a case control study investigating severe anemia. Using multiplex real-time PCR, hookworm infections were found in 34.1% of the severely anemic cases and in 27.0% of the non-severely anemic controls (p<0.05) whereas a 5.6% hookworm prevalence was detected by microscopy. Prevalence of A. duodenale and N. americanus was 26.1% and 4.9% respectively. Moderate and high load A. duodenale infections were positively associated with severe anemia (adjusted odds ratio: 2.49 (95%CI 1.16-5.33) and 9.04 (95%CI 2.52-32.47) respectively). Iron deficiency (assessed through bone marrow examination) was positively associated with intensity of A. duodenale infection (adjusted odds ratio: 3.63 (95%CI 1.18-11.20); 16.98 (95%CI 3.88-74.35) and 44.91 (95%CI 5.23-385.77) for low, moderate and high load respectively). CONCLUSIONS/SIGNIFICANCE: This is the first report assessing the association of hookworm load and species differentiation with severe anemia and bone marrow iron deficiency. By revealing a much higher than expected prevalence of A. duodenale and its significant and load-dependent association with severe anemia and iron deficiency in pre-school children in Malawi, we demonstrated the need for quantitative and species-specific screening of hookworm infections. Multiplex real-time PCR is a powerful diagnostic tool for public health research to combat (severe) anemia and iron deficiency in children living in resource poor settings.


Assuntos
Ancylostoma/isolamento & purificação , Ancilostomíase/complicações , Ancilostomíase/epidemiologia , Anemia/epidemiologia , Anemia/etiologia , Deficiências de Ferro , Ancylostoma/patogenicidade , Animais , Pré-Escolar , Feminino , Humanos , Lactente , Malaui/epidemiologia , Masculino , Reação em Cadeia da Polimerase Multiplex , Necator americanus/isolamento & purificação , Necator americanus/patogenicidade , Carga Parasitária , Prevalência , Reação em Cadeia da Polimerase em Tempo Real
10.
Atten Defic Hyperact Disord ; 3(1): 21-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21432615

RESUMO

ADHD prevalence has risen in parallel with rising prevalence of pregnancy smoking and childhood obesity. The objective was to determine the epidemiological association of pregnancy smoking and childhood obesity with ADHD. A cross-sectional community study was conducted in 2006 using a parental questionnaire. A total of 1,074 schoolchildren aged 5-11 years were enrolled from 15 primary schools in a lower socio-economic area of Merseyside. ADHD was defined by the question "does your child have Attention Deficit Hyperactivity Disorder, (ADHD), which has been diagnosed by a doctor?" The prevalence estimates for childhood obesity, maternal smoking during pregnancy and childhood ADHD were 14.9% (116/777), 28.0% (269/955), and 3.4% (32/945), respectively. ADHD prevalence increased fivefold in children with obesity (RR, 4.80, 95% CI 2.2-10.4, P < 0.001) and more than twofold in children of mothers who smoked during pregnancy (RR, 2.44, 95% CI 1.2-4.9, P = 0.02). Regression analysis adjusting for obesity, overweight, maternal smoking during pregnancy, heavy maternal smoking, household member smoking during pregnancy, doctor-diagnosed asthma, preterm birth, and low birthweight showed significant independent associations of ADHD prevalence with obesity (AOR, 4.66, 95% CI 1.57-13.89, P = 0.006) and pregnancy smoking (AOR, 3.19, 95% CI 1.08-9.49, P = 0.04). There was a positive dose-response association of ADHD with the number of maternal cigarettes smoked during pregnancy. Measures to reduce both smoking among pregnant women and childhood obesity might reduce prevalence of childhood ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Comportamento Materno , Obesidade/epidemiologia , Fumar , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Masculino , Obesidade/etiologia , Sobrepeso/epidemiologia , Sobrepeso/etiologia , Gravidez , Prevalência , Fatores de Risco , Fumar/epidemiologia , Inquéritos e Questionários , Reino Unido
11.
Malar J ; 10: 47, 2011 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-21345193

RESUMO

BACKGROUND: Nutritional iron deficiency may limit iron availability to the malaria parasite reducing infection risk, and/or impair host immunity thereby increasing this risk. In pregnant women, there is evidence of an adverse effect with iron supplementation, but the few reported studies are strongly confounded. METHODS: A case control study in pregnant Malawian women was undertaken in Chikhwawa southern Malawi in order to describe iron status in relation to placental malaria controlling for several confounding factors. Pregnancy characteristics were obtained and a blood sample at delivery. A full blood count was performed and serum ferritin and transferrin receptor quantified by enzyme-linked immunoassay. DNA analysis was used to identify genetic polymorphisms for ABO phenotype, hemoglobin HbS, and glucose -6 phosphate dehydrogenase deficiency. Placental tissue was obtained and malaria histology classified as active, past or no malaria infection. RESULTS: 112 cases with placental malaria were identified and 110 women with no evidence of placental infection. Iron deficiency was less frequent in women with placental Plasmodium falciparum infection. In those with acute, chronic or past placental infections the odds ratio for iron deficiency was 0.4, 95% CI 0.2-0.8, p = 0.01; for acute and chronic infections 0.4, 0.2-0.8, p = 0.006; for acute infection 0.3, 0.1-0.7, p = 0.001. The association was greater in multigravidae. CONCLUSION: Women with either acute, or acute and chronic placental malaria were less likely to have iron deficiency than women without placental malaria infection There is a priority to establish if reversing iron deficiency through iron supplementation programs either prior to or during pregnancy enhances malaria risk.


Assuntos
Deficiências de Ferro , Malária Falciparum/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Sistema ABO de Grupos Sanguíneos/genética , Contagem de Células Sanguíneas , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Ferritinas/sangue , Glucosefosfato Desidrogenase/genética , Hemoglobina Falciforme/genética , Humanos , Malaui/epidemiologia , Polimorfismo Genético , Gravidez , Receptores da Transferrina/sangue , Medição de Risco
12.
Eur J Public Health ; 21(3): 286-91, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21126981

RESUMO

BACKGROUND: The combined dose response effects of pregnancy cigarette smoke exposure on childhood overweight, obesity and short stature have not been reported. METHOD: A community based cross-sectional survey of 3038 children aged 5-11 years from 15 primary schools in Merseyside, UK. Self-completed parental questionnaires were used for family characteristics, socio-economic status and parental smoking practices. Children were measured for height and weight and z-scores calculated for parental smoking categories. RESULTS: Of 689 (34.0%) mothers who smoked during pregnancy 50.5% smoked ten or more cigarettes daily (heavy smokers). Children of maternal non-smokers had prevalence estimates for overweight, obesity and short stature of 25, 9.6 and 3.2%, respectively. Prevalence estimates were higher in children of mothers who were heavy smokers during pregnancy, 31.5% (P = 0.001), 15.6% (P < 0.001) and 5.5% (P = 0.001), respectively. Mean height for age z-scores was lower among heavy maternal (P < 0.001) and paternal smokers (P < 0.01) compared to non-smokers. Childhood overweight, obesity or short stature were all associated with heavy maternal smoking during pregnancy (all P < 0.001). Mean body mass index (BMI) z-scores were higher in boys of mothers who smoked (P = 0.043). The adjusted odds ratio for short stature in children of heavy maternal smokers was 2.76 (95% CI 1.21-6.33) and 4.28 (1.37-13.37) if both parents were heavy smokers. The adjusted OR for obesity in children of maternal smokers was 1.61(1.19-2.18). The population attributable risk for short stature was 8.8% (1.1-22.7) for heavy maternal smokers. CONCLUSION: A dose-response association was observed between pregnancy smoking exposure, short stature and obesity.


Assuntos
Estatura , Obesidade/epidemiologia , Efeitos Tardios da Exposição Pré-Natal , Fumar/efeitos adversos , Criança , Pré-Escolar , Estudos Transversais , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Razão de Chances , Sobrepeso/epidemiologia , Pais , Gravidez , Prevalência , Fatores de Risco , Inquéritos e Questionários
13.
AIDS ; 24(18): 2883-7, 2010 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-20871386

RESUMO

Anemia is common in HIV infection, but the pathophysiology is poorly understood. Bone marrow analysis in 329 severely anemic (hemoglobin <5 g/dl) Malawian children with (n = 40) and without (n = 289) HIV infection showed that HIV-infected children had fewer CD34(+) hematopoietic progenitors (median 10 vs. 15‰, P = 0.04) and erythroid progenitors (2.2 vs. 3.4‰, P = 0.05), but there were no differences in erythrocyte viability and maturation in later stages of erythropoiesis. Despite an HIV-associated reduction in early red cell precursors, subsequent erythropoiesis appears to proceed similarly in HIV-infected and HIV-uninfected children with severe anemia.


Assuntos
Anemia/imunologia , Medula Óssea/virologia , Eritropoese/imunologia , Infecções por HIV/imunologia , HIV-1 , Estudos de Casos e Controles , Pré-Escolar , Feminino , Infecções por HIV/complicações , Humanos , Lactente , Masculino , Filogenia
14.
Acta Obstet Gynecol Scand ; 89(8): 1011-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20528200

RESUMO

OBJECTIVE: To describe pregnancy outcomes of adolescent and adult primigravidae receiving antimalarials and hematinic supplementation and compare findings with a survey in this area a decade earlier. DESIGN: Cross-sectional surveys in intervention and control sites. SETTING: Community, antenatal and delivery facilities in Chikwawa, Malawi. A rural area with year round malaria transmission. METHODS: Data on antenatal attendance, uptake of intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP), birthweight, malaria, anaemia, for 2,152 primigravidae. OUTCOME MEASURES: Place of delivery, anaemia, malaria, birthweight. RESULTS: Fewer adolescent than adult primigravidae received >or=2 IPTp-SP doses (66 vs. 77.2%, p < 0.001), although more attended for two or more antenatal visits (92.0 vs. 76.7%, p < 0.001). Only 24.1% of adolescent primigravidae attended for hospital delivery. Women resident in intervention sites receiving IPTp-SP community distribution were more likely to choose a community delivery (p < 0.01), and have higher uptake of IPTp-SP (p = 0.036) than women not resident in these villages. Postnatal malaria prevalence was low and did not differ by age or place of delivery. Postnatal anaemia and low birthweight prevalence were higher in adolescents with community deliveries. Maternal anaemia and low birthweight prevalence were lower amongst adolescents in this study compared to estimates from the same population a decade previously. CONCLUSIONS: Adolescents had higher anaemia risk, lower IPTp-SP uptake than adults and under a quarter had a hospital delivery. Pregnancy outcomes improved compared to the survey a decade earlier. Monitoring and surveillance is required to reinforce to policy makers the need to improve adolescent coverage for available interventions.


Assuntos
Antimaláricos/uso terapêutico , Hematínicos/uso terapêutico , Resultado da Gravidez , Adolescente , Adulto , Anemia/epidemiologia , Estudos Transversais , Parto Obstétrico , Combinação de Medicamentos , Feminino , Compostos Ferrosos/uso terapêutico , Ácido Fólico/uso terapêutico , Inquéritos Epidemiológicos , Hospitais/estatística & dados numéricos , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Malária/prevenção & controle , Malaui , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Cuidado Pré-Natal/estatística & dados numéricos , Pirimetamina/uso terapêutico , Serviços de Saúde Rural , População Rural , Sulfadoxina/uso terapêutico
15.
Ann Hum Biol ; 37(6): 789-800, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20545487

RESUMO

BACKGROUND: A recent decline in the male:female (M:F) sex ratio may relate to pregnancy cigarette smoke exposure. AIM: To assess trends and cigarette exposure dose-response effects on the sex ratio. SUBJECTS AND METHODS: A retrospective analysis was carried out of deliveries at the Liverpool Women's Hospital between 1998 and 2003, and of deliveries reported in community surveys from the same area in 1998 and 2006. RESULTS: For the hospital sample, the M:F sex ratio was 1.14 if no parent smoked, and 0.77 when both parents smoked during the mother's pregnancy (p < 0.001). Heavy maternal smokers (>10 cigarettes per day) were more likely to deliver a female baby than light smokers (p < 0.001). Smoking was associated with increased likelihood of female birth controlling for birth year, socio-economic status, alcohol exposure, maternal haemoglobin and body mass index (adjusted OR: 1.41, 95% CI 1.12-1.92, p < 0.001). In the community sample controlling for socio-economic status the ratios were 1.13 (95% CI 1.03-1.24, p = 0.015) in 1998 and 1.31 (95% CI 1.16-1.48, p < 0.001) in 2006. Secular trends showed decreasing ratios in hospital and community samples for both smokers and non-smokers. CONCLUSION: Pregnancy cigarette smoking increased the proportion of female births with evidence for a dose-response association.


Assuntos
Pais , Gravidez , Razão de Masculinidade , Fumar , Relação Dose-Resposta a Droga , Inglaterra , Feminino , Humanos , Exposição por Inalação , Masculino , Probabilidade , Estudos Retrospectivos , Poluição por Fumaça de Tabaco
16.
Eur J Obstet Gynecol Reprod Biol ; 143(1): 38-42, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19147266

RESUMO

OBJECTIVES: To determine the role of maternal CYP1A1, GSTT1, and GSTM1 metabolic gene polymorphisms in modulating the association between pregnancy smoking exposure and fetal growth restriction. STUDY DESIGN: A case-control study was conducted to investigate if the association of pregnancy smoking and birth outcome was modulated by maternal gene polymorphisms. A total of 90 mothers with an IUGR baby (cases) and 180 mothers without IUGR (controls) were enrolled. RESULTS: Almost half of smokers who carried a CYP1A1 variant (51.3%), GSTT1 null (43.6%), or GSTM1 null genotypes (64.1%) delivered a baby with IUGR. Smokers with the variant CYP1A1 "aa" genotype had babies with lower mean birthweight than non-smokers with the same genotype (p=0.004). An interaction test showed increased prevalence of IUGR in smokers with the CYP1A1 (Aa/aa) variant (adjusted OR, 1.9; 95% CI, 1.4-5.5, p=0.01), or with the GSTT1 null (AOR, 1.5; 1.1-3.1, p=0.001), or GSTM1 null genotypes (AOR, 1.5; 1.2-3.7, p=0.001). CONCLUSIONS: Risk of fetal growth restriction in mothers who smoked during pregnancy was modulated by maternal metabolic gene polymorphisms. The genetic control of the conversion of toxic metabolites of tobacco smoke to less damaging substances is important for maternal and fetal health.


Assuntos
Peso ao Nascer , Citocromo P-450 CYP1A1/genética , Retardo do Crescimento Fetal/genética , Glutationa Transferase/genética , Fumar/efeitos adversos , Estudos de Casos e Controles , Feminino , Humanos , Polimorfismo Genético , Gravidez , Fatores de Risco
17.
Ann Hum Biol ; 35(6): 573-83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18932054

RESUMO

BACKGROUND: Prenatal smoking exposure causes intrauterine fetal growth restriction (IUGR), although its effects on fetal proportionality are less clearly defined. AIM: The present study assessed fetal proportionality in babies with IUGR using maternal salivary cotinine to indicate maternal smoking exposure. SUBJECTS AND METHODS: A case-control study at the Liverpool Women's Hospital, UK of babies with asymmetric and symmetric IUGR and non-growth restricted babies was carried out. RESULTS: 270 white women including 90 IUGR cases and 180 controls were enrolled. Asymmetry presented in 52.2% of IUGR cases. Geometric mean maternal cotinine concentration was higher with asymmetric (p=0.002) than symmetric IUGR (p=0.07), when compared to controls. Maternal smoking exposure was independently associated with asymmetric IUGR (OR 2.4, 95% CI, 1.5-4.4, p

Assuntos
Retardo do Crescimento Fetal/induzido quimicamente , Gravidez/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Fumar/efeitos adversos , Tamanho Corporal/efeitos dos fármacos , Estudos de Casos e Controles , Cotinina/análise , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Humanos , Lactente , Exposição Materna/efeitos adversos , Troca Materno-Fetal , Somatotipos , Teratogênicos/toxicidade
18.
J Womens Health (Larchmt) ; 17(6): 965-70, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18554095

RESUMO

BACKGROUND: Pregnancy in older women is of great relevance, particularly in developed countries where many women experience pregnancy late in the childbearing age. METHODS: A hospital-based data analysis of 9506 delivery records from 1998 to 2003 at the Liverpool Women's Hospital was undertaken to assess pregnancy outcomes in older women of reproductive age. RESULTS: Overall, 2.4 % of mothers were >40 years of age (advanced), 5.6% were <20 years (adolescents), and 92% were between 20 and 40 years. The prevalence of low birthweight (LBW), preterm birth, and small for gestational age by maternal age category followed a U-shaped curve with nadirs in the middle age classes. The gestational age of older mothers was 1 week shorter than that for women aged 26-30 years (p = 0.005). Primiparaes >40 years were at higher risk for delivering a LBW (9.4% vs. 5.3%, p = 0.005) or a very preterm baby (8.9% vs. 4.4%, p = 0.001) than were multiparous mothers of the same age. There was an association between maternal advanced age and LBW (adjusted OR [AOR], 1.7, 95% CI 1.4-2.5, p = 0.001), preterm birth (AOR 1.4, 95% CI 1.1-2.4, p = 0.04), or very preterm birth (AOR 1.6, 95% CI 1.2-3.5, p = 0.002) after controlling for prenatal alcohol and smoking exposure, household deprivation, maternal anemia, obesity, parity, and single parenthood. CONCLUSIONS: Pregnancy in older women is associated with adverse birth outcomes, particularly in primigravidas. Increased health promotion is required to highlight the risk of adverse birth outcomes in women who become pregnant for the first time in the late childbearing years.


Assuntos
Idade Materna , Complicações na Gravidez/etiologia , Resultado da Gravidez/epidemiologia , Gravidez de Alto Risco , Adulto , Feminino , Idade Gestacional , Hospitais , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Pessoa de Meia-Idade , Paridade , Gravidez , Complicações na Gravidez/epidemiologia , Nascimento Prematuro , Prevalência , Sistema de Registros , Análise de Regressão , Estudos Retrospectivos , Risco , Fumar/efeitos adversos , Fatores Socioeconômicos , Reino Unido/epidemiologia
19.
Matern Child Health J ; 12(2): 188-93, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17557199

RESUMO

Due to impaired airway function, children are at risk for adverse respiratory symptoms if exposed to environmental tobacco smoke (ETS). A community-based, cross-sectional study of 425 children (5-11 years) attending 15 primary schools in a low socio-economic area of Merseyside/UK was undertaken to investigate the association of adverse respiratory symptoms and ETS exposure using a parent-completed questionnaire and children's salivary cotinine measurements. Overall, 28.9% of children had doctor-diagnosed asthma (DDA) and 11.3% a history of hospital admission for respiratory illnesses. The symptom triad of cough, wheeze and breathlessness (C+W+B+) occurred in 12.6% of children. The geometric mean cotinine level was 0.37 ng/ml (95% CI, 0.33-0.42 ng/ml) and it was estimated that 45.6% of children were ETS exposed. A history of asthma in the family was reported for 9.2% of fathers and 7.2% of mothers. Salivary cotinine level was significantly increased in children with DDA compared to those without (P = 0.002). Cotinine-validated levels [adjusted odds ratio (AOR), 1.8; 95% CI, 1.4-2.5), low socio-economic (disadvantaged) status (AOR, 1.4; 1.1-2.9), child's male gender (AOR, 1.6; 1.1-2.5) and maternal smoking (AOR, 2.2; 1.4-3.1) were significantly associated with DDA. The cotinine-validated level (AOR, 1.4; 1.1-2.9) as well as maternal smoking (AOR, 1.8; 1.1-2.5), were also independently associated with C+W+B+. The use of salivary cotinine as an indicator of ETS exposure could be used to inform parents of exposure risk to their asthmatic children and may help re-enforce deterrent efforts to reduce childhood parental smoking exposure.


Assuntos
Asma/metabolismo , Cotinina/análise , Saliva/química , Poluição por Fumaça de Tabaco/efeitos adversos , Asma/diagnóstico , Asma/epidemiologia , Asma/etiologia , Criança , Pré-Escolar , Tosse/etiologia , Estudos Transversais , Dispneia/etiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Áreas de Pobreza , Sons Respiratórios/etiologia , Instituições Acadêmicas , Fumar/efeitos adversos , Fumar/epidemiologia , Classe Social , Inquéritos e Questionários , Reino Unido/epidemiologia
20.
J Child Health Care ; 10(2): 140-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16707542

RESUMO

OBJECTIVE: To assess the influence of socio-economic status on pregnancy outcomes in smoking mothers. STUDY DESIGN: Retrospective analysis. METHODS: Parent-completed questionnaires addressing pregnancy smoking patterns and birth outcomes. Were distributed via children aged 5-11 years attending 10 primary schools in Merseyside. Data from three community-based cross-sectional surveys undertaken in 1993, 1998 and 2001 were analysed. Townsend score was used as an indicator of household socioeconomic status. RESULTS: 82.2 percent (n = 3730) of respondents were classified as low (disadvantaged) socio-economic status. One-third of mothers smoked during pregnancy and this proportion was significantly higher among disadvantaged than advantaged categories (37.7% versus 14.6%; p < 0.001). The logistic regression analysis showed that only maternal smoking during pregnancy was a significant risk factor for adverse birth outcomes when socioeconomic variables were controlled. CONCLUSION: Birth outcomes were worse in babies of smoking mothers during pregnancy independent of household's socio-economic status.


Assuntos
Retardo do Crescimento Fetal/epidemiologia , Recém-Nascido de Baixo Peso , Recém-Nascido Prematuro , Fumar/efeitos adversos , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Modelos Logísticos , Masculino , Análise Multivariada , Gravidez , Estudos Retrospectivos , Fumar/epidemiologia , Fatores Socioeconômicos , Reino Unido/epidemiologia
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