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1.
Am J Clin Nutr ; 119(1): 221-231, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37890672

RESUMO

BACKGROUND: Copper (Cu), an essential trace mineral regulating multiple actions of inflammation and oxidative stress, has been implicated in risk for preterm birth (PTB). OBJECTIVES: This study aimed to determine the association of maternal Cu concentration during pregnancy with PTB risk and gestational duration in a large multicohort study including diverse populations. METHODS: Maternal plasma or serum samples of 10,449 singleton live births were obtained from 18 geographically diverse study cohorts. Maternal Cu concentrations were determined using inductively coupled plasma mass spectrometry. The associations of maternal Cu with PTB and gestational duration were analyzed using logistic and linear regressions for each cohort. The estimates were then combined using meta-analysis. Associations between maternal Cu and acute-phase reactants (APRs) and infection status were analyzed in 1239 samples from the Malawi cohort. RESULTS: The maternal prenatal Cu concentration in our study samples followed normal distribution with mean of 1.92 µg/mL and standard deviation of 0.43 µg/mL, and Cu concentrations increased with gestational age up to 20 wk. The random-effect meta-analysis across 18 cohorts revealed that 1 µg/mL increase in maternal Cu concentration was associated with higher risk of PTB with odds ratio of 1.30 (95% confidence interval [CI]: 1.08, 1.57) and shorter gestational duration of 1.64 d (95% CI: 0.56, 2.73). In the Malawi cohort, higher maternal Cu concentration, concentrations of multiple APRs, and infections (malaria and HIV) were correlated and associated with greater risk of PTB and shorter gestational duration. CONCLUSIONS: Our study supports robust negative association between maternal Cu and gestational duration and positive association with risk for PTB. Cu concentration was strongly correlated with APRs and infection status suggesting its potential role in inflammation, a pathway implicated in the mechanisms of PTB. Therefore, maternal Cu could be used as potential marker of integrated inflammatory pathways during pregnancy and risk for PTB.


Assuntos
Nascimento Prematuro , Gravidez , Feminino , Humanos , Recém-Nascido , Cobre , Idade Gestacional , Nascido Vivo , Inflamação , Fatores de Risco
2.
Trials ; 24(1): 733, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968741

RESUMO

BACKGROUND: The Large-scale Assessment of the Key health-promoting Activities of two New mass drug administration regimens with Azithromycin (LAKANA) trial in Mali aims to evaluate the efficacy and safety of azithromycin (AZI) mass drug administration (MDA) to 1-11-month-old infants as well as the impact of the intervention on antimicrobial resistance (AMR) and mechanisms of action of azithromycin. To improve the transparency and quality of this clinical trial, we prepared this statistical analysis plan (SAP). METHODS/DESIGN: LAKANA is a cluster randomized trial that aims to address the mortality and health impacts of biannual and quarterly AZI MDA. AZI is given to 1-11-month-old infants in a high-mortality setting where a seasonal malaria chemoprevention (SMC) program is in place. The participating villages are randomly assigned to placebo (control), two-dose AZI (biannual azithromycin-MDA), and four-dose AZI (quarterly azithromycin-MDA) in a 3:4:2 ratio. The primary outcome of the study is mortality among the intention-to-treat population of 1-11-month-old infants. We will evaluate relative risk reduction between the study arms using a mixed-effects Poisson model with random intercepts for villages, using log link function with person-years as an offset variable. We will model outcomes related to secondary objectives of the study using generalized linear models with considerations on clustering. CONCLUSION: The SAP written prior to data collection completion will help avoid reporting bias and data-driven analysis for the primary and secondary aims of the trial. If there are deviations from the analysis methods described here, they will be described and justified in the publications of the trial results. TRIAL REGISTRATION: ClinicalTrials.gov ID NCT04424511 . Registered on 11 June 2020.


Assuntos
Azitromicina , Malária , Humanos , Lactente , Antibacterianos/efeitos adversos , Quimioprevenção , Malária/tratamento farmacológico , Malária/prevenção & controle , Malária/epidemiologia , Mali , Administração Massiva de Medicamentos , Método Duplo-Cego
3.
Chemosphere ; 342: 140144, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37704082

RESUMO

Maternal metal (loid)s exposure has been related to birth outcomes but the results are still inconclusive. Most previous studies have discussed the single metal (loid)s, neglecting the scene of co-exposure. We examined the associations of both single metal (loid)s and metal mixtures with birth outcomes in a birth cohort from the Tibetan Plateau, including body weight, body length, head circumference, small for gestational age (SGA), and Ponderal index (PI). In our analysis of 1069 women, we measured 29 metal (loid)s in urine samples in the third trimester. The associations of single metal (loid)s with categorical or continuous birth outcomes were evaluated using a generalized linear mixed-effects model or linear mixed-effects model, respectively. The least absolute shrinkage and selection operator, Bayesian kernel machine, and Quantile g-computation regression were used to explore the joint association. We also evaluated the interactive effects of ethnicity and altitude on the effect of metal (loid)s on birth outcomes. Copper (Cu) concentration in maternal urine was positively associated with SGA, birth weight, birth length, and head circumference in the single pollutant models. For instance, Cu was associated with an increased risk of SGA [OR (95% CI) = 1.56 (1.23, 1.97); P < 0.001]. We didn't find significant joint association of metal mixtures with birth outcomes except a positive association between the mixture of Cu, Magnesium (Mg), and Iron (Fe) with the risk of SGA when the exposure level was above its 80th percentile, and Cu dominated the adverse association in a non-linear manner. Living altitude modified the associations of Cu with SGA and the positive association was only found in participants living at high altitude. In conclusion, maternal urinary metal (loid)s, especially Cu, was the dominant harmful metal (loid)s when associated with SGA on the Tibetan Plateau.


Assuntos
Recém-Nascido Pequeno para a Idade Gestacional , Metais , Gravidez , Recém-Nascido , Humanos , Feminino , Teorema de Bayes , Tibet , Peso ao Nascer , Retardo do Crescimento Fetal
4.
Malar J ; 22(1): 266, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697296

RESUMO

BACKGROUND: The complex interaction between malaria and undernutrition leads to increased mortality and morbidity rate among young children in malaria-endemic regions. Results from previous interventions suggest that improving nutritional status of young children may reduce the burden of malaria. This study tested a hypothesis that provision of lipid-based nutrient supplements (LNS) or corn-soy blend (CSB) supplementation to 6-18-month-old children in Malawi would reduce the prevalence of asymptomatic malaria among them. METHODS: A total of 840 6-month-old children were enrolled in a randomized trial. The participants received 12-month supplementation with three different daily dietary supplementations: CSB, soy-LNS, or milk-LNS, and one control group without supplementation. The prevalence rate of asymptomatic Plasmodium falciparum was determined by real-time PCR from the participant's dried blood spots (DBS) collected at the baseline and every 3 months. The global null hypothesis was tested using modified Poisson regression to estimate the prevalence ratio (PR) between the control group and three intervention groups at all ages combined. All the models were adjusted for malaria at baseline, season of DBS sample collection, site of enrolment, and household asset Z-score. RESULTS: All children combined, the prevalence of P. falciparum was 14.1% at enrollment, 8.7% at 9 months, 11.2% at 12 months, 13.0% at 15 months and 22.4% at 18 months of age. Among all samples that were taken after enrolment, the prevalence was 12.1% in control group, 12.2% in milk-LNS, 14.0% in soy-LNS, and 17.2% in CSB group. Compared to children in the control group the prevalence ratio of positive malaria tests was 1.19 (95% CI 0.81-1.74; P = 0.372) in the milk-LNS group, 1.32 (95% CI 0.88-1.96; P = 0.177) in the soy-LNS group and 1.72 (95% CI 1.19-2.49; P = 0.004) in the CSB group. CONCLUSION: The study findings do not support a hypothesis that LNS or CSB supplementation would reduce the prevalence of asymptomatic malaria among Malawian children. In contrast, there was a signal of a possible increase in malaria prevalence among children supplemented with CSB.


Assuntos
Malária Falciparum , Malária , Humanos , Criança , Pré-Escolar , Lactente , Malaui/epidemiologia , Prevalência , Suplementos Nutricionais , Malária/epidemiologia , Malária/prevenção & controle , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Zea mays
5.
Am J Trop Med Hyg ; 108(4): 768-776, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36780896

RESUMO

Maternal malaria and infections during pregnancy are risk factors for fetal growth restriction. We assessed the impact of preventive treatment in pregnancy on maternal malaria and fetal growth. Between 2003 and 2006, we enrolled 1,320 pregnant Malawian women, 14-26 gestation weeks, in a randomized trial and treated them with two doses of sulfadoxine-pyrimethamine (SP, control) at enrollment and between 28-34 gestation weeks; with monthly SP from enrollment until 37 gestation weeks; or with monthly SP and azithromycin twice, at enrollment and between 28 and 34 gestation weeks (AZI-SP). Participants were seen at 4-week intervals until 36 completed gestation weeks and weekly thereafter. At each visit, we collected dried blood spots for real-time polymerase chain reaction diagnosing of malaria parasitemia and, in a random subgroup of 341 women, we measured fetal biparietal diameter and femur length with ultrasound. For the monthly SP versus the control group, the odds ratios (OR) (95% CI) of malaria parasitemia during the second, third, and both trimesters combined were 0.79 (0.46-1.37), 0.58 (0.37-0.92), and 0.64 (0.42-0.98), respectively. The corresponding ORs for the AZI-SP versus control group were 0.47 (0.26-0.84), 0.51 (0.32-0.81), and 0.50 (0.32-0.76), respectively. Differences between the AZI-SP and the monthly SP groups were not statistically significant. The interventions did not affect fetal biparietal diameter and femur length growth velocity. The results suggest that preventive maternal treatment with monthly SP reduced malaria parasitemia during pregnancy in Malawi and that the addition of azithromycin did not provide much additional antimalarial effect.


Assuntos
Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Feminino , Gravidez , Humanos , Azitromicina/uso terapêutico , Parasitemia/tratamento farmacológico , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina/uso terapêutico , Malária/prevenção & controle , Antimaláricos/uso terapêutico , Combinação de Medicamentos , Desenvolvimento Fetal
6.
Trials ; 24(1): 5, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597115

RESUMO

BACKGROUND: Mass drug administration (MDA) of azithromycin (AZI) has been shown to reduce under-5 mortality in some but not all sub-Saharan African settings. A large-scale cluster-randomized trial conducted in Malawi, Niger, and Tanzania suggested that the effect differs by country, may be stronger in infants, and may be concentrated within the first 3 months after treatment. Another study found no effect when azithromycin was given concomitantly with seasonal malaria chemoprevention (SMC). Given the observed heterogeneity and possible effect modification by other co-interventions, further trials are needed to determine the efficacy in additional settings and to determine the most effective treatment regimen. METHODS: LAKANA stands for Large-scale Assessment of the Key health-promoting Activities of two New mass drug administration regimens with Azithromycin. The LAKANA trial is designed to address the mortality and health impacts of 4 or 2 annual rounds of azithromycin MDA delivered to 1-11-month-old (29-364 days) infants, in a high-mortality and malaria holoendemic Malian setting where there is a national SMC program. Participating villages (clusters) are randomly allocated in a ratio of 3:2:4 to three groups: placebo (control):4-dose AZI:2-dose AZI. The primary outcome measured is mortality. Antimicrobial resistance (AMR) will be monitored closely before, during, and after the intervention and both among those receiving and those not receiving MDA with the study drugs. Other outcomes, from a subset of villages, comprise efficacy outcomes related to morbidity, growth and nutritional status, outcomes related to the mechanism of azithromycin activity through measures of malaria parasitemia and inflammation, safety outcomes (AMR, adverse and serious adverse events), and outcomes related to the implementation of the intervention documenting feasibility, acceptability, and economic aspects. The enrolment commenced in October 2020 and is planned to be completed by the end of 2022. The expected date of study completion is December 2024. DISCUSSION: If LAKANA provides evidence in support of a positive mortality benefit resulting from azithromycin MDA, it will significantly contribute to the options for successfully promoting child survival in Mali, and elsewhere in sub-Saharan Africa. TRIAL REGISTRATION: ClinicalTrials.gov NCT04424511. Registered on 11 June 2020.


Assuntos
Azitromicina , Administração Massiva de Medicamentos , Humanos , Lactente , Antibacterianos/efeitos adversos , Azitromicina/efeitos adversos , Mortalidade Infantil , Malária/prevenção & controle , Mali/epidemiologia , Administração Massiva de Medicamentos/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
7.
Matern Child Nutr ; 19(1): e13417, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36111423

RESUMO

Inadequate diet and frequent symptomatic infections are considered major causes of growth stunting in low-income countries, but interventions targeting these risk factors have achieved limited success. Asymptomatic infections can restrict growth, but little is known about their role in global stunting prevalence. We investigated factors related to length-for-age Z-score (LAZ) at 24 months by constructing an interconnected network of various infections, biomarkers of inflammation (as assessed by alpha-1-acid glycoprotein [AGP]), and growth (insulin-like growth factor 1 [IGF-1] and collagen X biomarker [CXM]) at 18 months, as well as other children, maternal, and household level factors. Among 604 children, there was a continuous decline in mean LAZ and increased mean length deficit from birth to 24 months. At 18 months of age, the percentage of asymptomatic children who carried each pathogen was: 84.5% enterovirus, 15.5% parechovirus, 7.7% norovirus, 4.6% rhinovirus, 0.6% rotavirus, 69.6% Campylobacter, 53.8% Giardia lamblia, 11.9% malaria parasites, 10.2% Shigella, and 2.7% Cryptosporidium. The mean plasma IGF-1 concentration was 12.5 ng/ml and 68% of the children had systemic inflammation (plasma AGP concentration >1 g/L). Shigella infection was associated with lower LAZ at 24 months through both direct and indirect pathways, whereas enterovirus, norovirus, Campylobacter, Cryptosporidium, and malaria infections were associated with lower LAZ at 24 months indirectly, predominantly through increased systemic inflammation and reduced plasma IGF-1 and CXM concentration at 18 months.


Assuntos
Criptosporidiose , Cryptosporidium , Malária , Pré-Escolar , Humanos , Lactente , Infecções Assintomáticas/epidemiologia , Biomarcadores , Cryptosporidium/metabolismo , Transtornos do Crescimento/epidemiologia , Inflamação , Fator de Crescimento Insulin-Like I
8.
Artigo em Inglês | MEDLINE | ID: mdl-36078607

RESUMO

Environmental enteric dysfunction (EED) is common and contributes to linear growth faltering (stunting) and mortality among children in low-resource settings. A few studies on the environmental causes of EED have been conducted but the exact exposures that cause or predispose children to EED are context-specific and not clear. This study aimed to assess associations between selected environmental exposures and EED markers among 620 18-month-old children. This was a secondary analysis of data from Malawian children who participated in a randomized controlled trial (iLiNS-DYAD, registered at clinicaltrials.gov as NCT01239693) from birth to 18 months of age. Data on environmental exposures, including drinking water source, sanitation, exposure to animals, housing materials, season, residential area, and food insecurity were collected at enrolment. Biomarkers of EED included concentrations of calprotectin, regenerating 1B protein (REG1B), and alpha-1-antitrypsin from stool samples to assess intestinal inflammation, repair, and permeability, respectively. We performed bivariate and multivariable analyses to assess associations between environmental exposures and EED biomarkers. Adjusting for possible confounders, we did not find associations between the selected environmental exposures and the three biomarkers. These results do not provide support for our hypothesis that the studied adverse environmental exposures are associated with increased concentrations of children's EED markers in rural Malawi.


Assuntos
Transtornos do Crescimento , Intestino Delgado , Animais , Biomarcadores/metabolismo , Exposição Ambiental/efeitos adversos , Humanos , Malaui/epidemiologia
9.
BMJ Open ; 12(6): e060367, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710236

RESUMO

OBJECTIVE: To estimate the degree of SARS-CoV-2 transmission among healthcare workers (HCWs) and general population in Kita region of Mali. DESIGN: Routine surveillance in 12 health facilities, HCWs serosurvey in five health facilities and community serosurvey in 16 villages in or near Kita town, Mali. SETTING: Kita region, western Mali; local health centres around the central (regional) referral health centre. PARTICIPANTS: Patients in routine surveillance, HCWs in local health centres and community members of all ages in populations associated with study health centres. MAIN OUTCOME MEASURES: Seropositivity of ELISA test detecting SARS-CoV-2-specific total antibodies and real-time RT-PCR confirmed SARS-CoV-2 infection. RESULTS: From 2392 routine surveillance samples, 68 (2.8%, 95% CI: 2.2% to 3.6%) tested positive for SARS-CoV-2 by RT-PCR. The monthly positivity rate was 0% in June-August 2020 and gradually increased to 6% by December 2020 and 6.2% by January 2021, then declined to 5.5%, 3.3%, 3.6% and 0.8% in February, March, April and May 2021, respectively. From 397 serum samples collected from 113 HCWs, 175 (44.1%, 95% CI: 39.1% to 49.1%) were positive for SARS-CoV-2 antibodies. The monthly seroprevalence was around 10% from September to November 2020 and increased to over 40% from December 2020 to May 2021. For community serosurvey in December 2020, overall seroprevalence of SARS-CoV-2 antibodies was 27.7%. The highest age-stratified seroprevalence was observed in participants aged 60-69 years (45.5%, 95% CI: 32.3% to 58.6%). The lowest was in children aged 0-9 years (14.0%, 95% CI: 7.4% to 20.6%). CONCLUSIONS: SARS-CoV-2 in rural Mali is much more widespread than assumed by national testing data and particularly in the older population and frontline HCWs. The observation is contrary to the widely expressed view, based on limited data, that COVID-19 infection rates were lower in 2020-2021 in West Africa than in other settings.


Assuntos
COVID-19 , Anticorpos Antivirais , COVID-19/diagnóstico , COVID-19/epidemiologia , Criança , Pessoal de Saúde , Humanos , Mali/epidemiologia , SARS-CoV-2 , Estudos Soroepidemiológicos
10.
Curr Dev Nutr ; 6(3): nzac013, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35317414

RESUMO

Background: Pregnant women in Malawi are at risk of selenium deficiency, which can have adverse effects on pregnancy outcomes. Interventions for improving selenium status are needed. Objectives: To assess the effect of provision of small-quantity lipid-based nutrient supplements (SQ-LNSs) to Malawian women during pregnancy on their plasma selenium concentrations at 36 wk of gestation. Methods: Pregnant women (≤20 wk of gestation) were randomly assigned to receive daily either: 1) iron and folic acid (IFA); 2) multiple micronutrients (MMN; 130 µg selenium per capsule); or 3) SQ-LNS (130 µg selenium/20 g). Plasma selenium concentrations were measured by inductively coupled plasma mass spectrometry at baseline and after ≥16 wk of intervention (at 36 wk of gestation) and compared by intervention group. Results: At 36 wk of gestation, median (quartile 1, quartile 3) plasma selenium concentrations (micromoles per liter) were 0.96 (0.73, 1.23), 0.94 (0.78, 1.18), and 1.01 (0.85, 1.28) in the IFA, MMN, and SQ-LNS groups, respectively. Geometric mean (GM) plasma selenium concentration was 5.4% (95% CI: 1.8%, 9.0%) higher in the SQ-LNS group than in the MMN group and tended to be higher than in the IFA group (+4.2%; 95% CI: 1.0%, 7.8%). The prevalence of adjusted plasma selenium concentrations <1 µmol/L was 55.1%, 57.8%, and 47.3% in the IFA, MMN, and SQ-LNS groups, respectively; it was lower in the SQ-LNS group than in the MMN group, OR = 0.44 (95% CI: 0.24, 0.83), and tended to be lower than in the IFA group, OR = 0.54 (95% CI: 0.29, 1.03). There was a significant interaction between baseline plasma selenium concentration and intervention group (P = 0.003). In the lowest tertile of baseline selenium concentrations, GM plasma selenium concentration was higher, and the prevalence of low values was lower in the SQ-LNS group compared with the MMN and IFA groups at 36 wk of gestation (P ≤ 0.007). Conclusions: Provision of SQ-LNS containing selenium to pregnant women can be an effective strategy for improving their selenium status.This trial was registered at clinicaltrials.gov (identifier: NCT01239693).

11.
Matern Child Nutr ; 18(3): e13331, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35128820

RESUMO

Lipid-based nutrient supplements (LNS) have been found to improve child growth and reduce child mortality. However, the mechanistic pathways for these improvements warrant exploration. One potential pathway is linked to improvement in intestinal health. Our study aimed to test a hypothesis that small-quantity LNS (SQ-LNS) could reduce the levels of intestinal inflammation, repair and permeability of children. As intestinal health markers we measured fecal calprotectin, regenerating 1B protein (REG1B) and alpha-1-antitrypsin concentrations at 18 months of age (after 12 months of supplementation) and 1 year later (12 months after cessation of supplementation). In this analysis, we included data of 735 children who participated in a randomised dietary supplementation trial in rural Malawi; 243 children who received 20 g/day SQ-LNS from 6 to 18 months of age were in the SQ-LNS group, while the others who received no dietary supplementation during this period were in the control group. At 18 months of age, the mean concentrations of calprotectin, REG1B and alpha-1-antitrypsin were 241, 105 µg/g and 7.1 mg/dl, respectively, in the SQ-LNS group, and 224, 105 µg/g and 7.4 mg/dl, respectively, in the control group, and did not differ between the SQ-LNS and control groups. We conclude that SQ-LNS provision did not have an impact on children's intestinal health in rural Malawi.


Assuntos
Suplementos Nutricionais , Nutrientes , Criança , Humanos , Lactente , Complexo Antígeno L1 Leucocitário , Lipídeos , Malaui , Micronutrientes , População Rural
12.
J Trop Pediatr ; 68(2)2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35149871

RESUMO

BACKGROUND: Environmental enteric dysfunction (EED) is common in low- and middle-income countries and associated with childhood undernutrition. The composition of gut microbiota has been implicated in the pathogenesis of EED. Our aim was to assess the associations between gut microbiota and EED biomarkers in rural Malawian children. We hypothesized that there would be an inverse association between microbiota maturity and diversity and fecal concentrations of EED biomarkers. METHODS: We used data from fecal samples collected at 6, 18 and 30 months from 611 children who were followed up during a nutrition intervention trial. The primary time point for analysis was 18 months. Microbiota data were obtained through 16S rRNA sequencing and variables included microbiota maturity and diversity, phylogenetic dissimilarity and relative abundances of individual taxa. EED biomarkers included calprotectin (marker of inflammation), alpha-1 antitrypsin (intestinal permeability) and REG1B (intestinal damage). RESULTS: There was an inverse association between microbiota maturity and diversity and fecal concentrations of all 3 EED biomarkers at 18 months (p≤0.001). The results were similar at 30 months, while at 6 months inverse associations were found only with calprotectin and alpha-1 antitrypsin concentrations. At 18 months, EED biomarkers were not associated with phylogenetic dissimilarity, but at 6 and 30 months several associations were observed. Individual taxa predicting EED biomarker concentrations at 18 months included several Bifidobacterium and Enterobacteriaceae taxa as well as potentially displaced oral taxa. CONCLUSIONS: Our findings support the hypothesis of an inverse association between microbiota maturity and diversity and EED in rural Malawian children.


Chronic childhood undernutrition is an important public health concern that affects about 150 million children, mostly in low- and middle-income countries. Undernutrition is caused by insufficient nutrient intake and frequent infections, but there are also other underlying factors. One of these is a condition called environmental enteric dysfunction (EED), which is characterized by intestinal inflammation and damage without apparent clinical symptoms. EED is thought to be caused by the ingestion of pathogenic bacteria that leads to changes in the intestine such as increased permeability and decreased absorptive capacity. This might make the intestinal wall vulnerable to bacterial invasion and reduce the absorption of nutrients. Besides potentially pathogenic bacteria, there are many commensal bacteria in the gastrointestinal tract that have beneficial functions and that interact with the immune system. The aim of our study was to assess the associations between all these bacteria, that is the intestinal microbiota and biomarkers of EED. We used data from fecal samples collected from young children participating in a nutrition intervention trial in rural Malawi. Our findings support an inverse association between the diversity and maturity of the intestinal microbiota and biomarkers of EED. Additionally, we identified the differences at the level of individual bacterial taxa (groups of bacteria defined by genetic similarity) between participants with different levels of EED biomarkers. Due to the type of study, we cannot determine whether the observed associations represent a causal relationship between the intestinal microbiota and EED. This as well as the exact mechanisms behind these associations should be assessed in further studies.


Assuntos
Microbioma Gastrointestinal , Criança , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Humanos , Inflamação , Permeabilidade , Filogenia , RNA Ribossômico 16S/genética
13.
Geohealth ; 6(1): e2021GH000452, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35024531

RESUMO

Diarrheal disease, still a major cause of childhood illness, is caused by numerous, diverse infectious microorganisms, which are differentially sensitive to environmental conditions. Enteropathogen-specific impacts of climate remain underexplored. Results from 15 studies that diagnosed enteropathogens in 64,788 stool samples from 20,760 children in 19 countries were combined. Infection status for 10 common enteropathogens-adenovirus, astrovirus, norovirus, rotavirus, sapovirus, Campylobacter, ETEC, Shigella, Cryptosporidium and Giardia-was matched by date with hydrometeorological variables from a global Earth observation dataset-precipitation and runoff volume, humidity, soil moisture, solar radiation, air pressure, temperature, and wind speed. Models were fitted for each pathogen, accounting for lags, nonlinearity, confounders, and threshold effects. Different variables showed complex, non-linear associations with infection risk varying in magnitude and direction depending on pathogen species. Rotavirus infection decreased markedly following increasing 7-day average temperatures-a relative risk of 0.76 (95% confidence interval: 0.69-0.85) above 28°C-while ETEC risk increased by almost half, 1.43 (1.36-1.50), in the 20-35°C range. Risk for all pathogens was highest following soil moistures in the upper range. Humidity was associated with increases in bacterial infections and decreases in most viral infections. Several virus species' risk increased following lower-than-average rainfall, while rotavirus and ETEC increased with heavier runoff. Temperature, soil moisture, and humidity are particularly influential parameters across all enteropathogens, likely impacting pathogen survival outside the host. Precipitation and runoff have divergent associations with different enteric viruses. These effects may engender shifts in the relative burden of diarrhea-causing agents as the global climate changes.

14.
J Nutr ; 152(1): 286-301, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34543432

RESUMO

INTRODUCTION: Small-quantity (SQ) lipid-based nutrient supplements (LNSs) may influence infants' plasma fatty acid (FA) profiles, which could be associated with short- and long-term outcomes. OBJECTIVES: We aimed to determine the impact of SQ-LNS consumption on infants' plasma FA profiles in Ghana and Malawi. METHODS: Ghanaian (n = 1320) and Malawian (n = 1391) women ≤20 weeks pregnant were assigned to consume 60 mg iron and 400 µg folic acid daily until delivery [iron and folic acid (IFA) group], multiple-micronutrient supplements (MMNs) until 6 months postpartum (MMN group), or SQ-LNSs (∼7.8 linoleic acid:α-linolenic acid ratio) until 6 months postpartum (LNS group). LNS group infants received SQ-LNS from 6 to 18 months of age. We compared infant plasma FAs by intervention group in subsamples (n = 379 in Ghana; n = 442 in Malawi) at 6 and 18 months using ANOVA and Poisson regression models. Main outcomes were mean percentage compositions (%Cs; percentage of FAs by weight) of α-linolenic acid (ALA), linoleic acid (LA), EPA, DHA, and arachidonic acid (AA). RESULTS: At 6 months, LNS infants had greater mean ± SD ALA %Cs in Ghana (0.23 ± 0.08; IFA, 0.21 ± 0.06; MMN, 0.21 ± 0.07; P = 0.034) and Malawi (0.42 ± 0.16; IFA, 0.38 ± 0.15; MMN, 0.38 ± 0.14; P = 0.034) and greater AA values in Ghana (6.25 ± 1.24; IFA, 6.12 ± 1.13; MMN, 5.89 ± 1.24; P = 0.049). At 18 months, LNS infants had a tendency towards greater ALA (0.32 ± 0.16; IFA, 0.24 ± 0.08; MMN, 0.24 ± 0.10; P = 0.06) and LA (27.8 ± 3.6; IFA, 26.9 ± 2.9; MMN, 27.0 ± 3.1; P = 0.06) in Ghana, and greater ALA (0.45 ± 0.18; IFA, 0.39 ± 0.18; MMN, 0.39 ± 0.18; P < 0.001) and LA (29.7 ± 3.5; IFA, 28.7 ± 3.3; MMN, 28.6 ± 3.4; P = 0.011) in Malawi. The prevalence of ALA below the population-specific 10th percentile was lower in the LNS group compared to the MMN group, but not the IFA group. Groups did not differ significantly in plasma EPA or DHA levels. CONCLUSIONS: SQ-LNS increased infants' plasma essential FA levels in Ghana and Malawi, which may have implications for health and developmental outcomes. These trials were registered at clinicaltrials.gov as NCT00970866 and NCT01239693.


Assuntos
Fenômenos Fisiológicos da Nutrição Materna , Micronutrientes , Suplementos Nutricionais , Ácidos Graxos Essenciais , Feminino , Gana , Humanos , Lactente , Lipídeos , Malaui , Nutrientes , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Am J Clin Nutr ; 114(Suppl 1): 68S-94S, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34590114

RESUMO

BACKGROUND: Small-quantity lipid-based nutrient supplements (SQ-LNSs) have been shown to reduce the prevalence of child anemia and iron deficiency, but effects on other micronutrients are less well known. Identifying subgroups who benefit most from SQ-LNSs could support improved program design. OBJECTIVES: We aimed to identify study-level and individual-level modifiers of the effect of SQ-LNSs on child hemoglobin (Hb), anemia, and inflammation-adjusted micronutrient status outcomes. METHODS: We conducted a 2-stage meta-analysis of individual participant data from 13 randomized controlled trials of SQ-LNSs provided to children 6-24 mo of age (n = 15,946). We generated study-specific and subgroup estimates of SQ-LNSs compared with control, and pooled the estimates using fixed-effects models. We used random-effects meta-regression to examine potential study-level effect modifiers. RESULTS: SQ-LNS provision decreased the prevalence of anemia (Hb < 110 g/L) by 16% (relative reduction), iron deficiency (plasma ferritin < 12 µg/L) by 56%, and iron deficiency anemia (IDA; Hb < 110 g/L and plasma ferritin <12 µg/L) by 64%. We observed positive effects of SQ-LNSs on hematological and iron status outcomes within all subgroups of the study- and individual-level effect modifiers, but effects were larger in certain subgroups. For example, effects of SQ-LNSs on anemia and iron status were greater in trials that provided SQ-LNSs for >12 mo and provided 9 (as opposed to <9) mg Fe/d, and among later-born (than among first-born) children. There was no effect of SQ-LNSs on plasma zinc or retinol, but there was a 7% increase in plasma retinol-binding protein (RBP) and a 56% reduction in vitamin A deficiency (RBP < 0.70 µmol/L), with little evidence of effect modification by individual-level characteristics. CONCLUSIONS: SQ-LNSs can substantially reduce the prevalence of anemia, iron deficiency, and IDA among children across a range of individual, population, and study design characteristics. Policy-makers and program planners should consider SQ-LNSs within intervention packages to prevent anemia and iron deficiency.This trial was registered at www.crd.york.ac.uk/PROSPERO as CRD42020156663.


Assuntos
Anemia Ferropriva/epidemiologia , Anemia/epidemiologia , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição do Lactente , Lipídeos/administração & dosagem , Estado Nutricional , África Subsaariana/epidemiologia , Bangladesh/epidemiologia , Pré-Escolar , Modificador do Efeito Epidemiológico , Feminino , Humanos , Lactente , Masculino , Micronutrientes/sangue , Micronutrientes/deficiência , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Viruses ; 13(3)2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804173

RESUMO

Three human protoparvoviruses, bufavirus (BuV), tusavirus (TuV) and cutavirus (CuV), have recently been discovered in diarrheal stool. BuV has been associated with diarrhea and CuV with cutaneous T-cell lymphoma, but there are hardly any data for TuV or CuV in stool or respiratory samples. Hence, using qPCR and IgG enzyme immunoassays, we analyzed 1072 stool, 316 respiratory and 445 serum or plasma samples from 1098 patients with and without gastroenteritis (GE) or respiratory-tract infections (RTI) from Finland, Latvia and Malawi. The overall CuV-DNA prevalences in stool samples ranged between 0-6.1% among our six patient cohorts. In Finland, CuV DNA was significantly more prevalent in GE patients above rather than below 60 years of age (5.1% vs 0.2%). CuV DNA was more prevalent in stools among Latvian and Malawian children compared with Finnish children. In 10/11 CuV DNA-positive adults and 4/6 CuV DNA-positive children with GE, no known causal pathogens were detected. Interestingly, for the first time, CuV DNA was observed in two nasopharyngeal aspirates from children with RTI and the rare TuV in diarrheal stools of two adults. Our results provide new insights on the occurrence of human protoparvoviruses in GE and RTI in different countries.


Assuntos
DNA Viral/genética , Gastroenteropatias/virologia , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Parvovirus/genética , Doenças Respiratórias/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , DNA Viral/análise , Fezes/virologia , Feminino , Finlândia/epidemiologia , Gastroenteropatias/epidemiologia , Humanos , Lactente , Letônia/epidemiologia , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Infecções por Parvoviridae/sangue , Parvovirus/classificação , Filogenia , Doenças Respiratórias/sangue , Doenças Respiratórias/epidemiologia , Adulto Jovem
17.
J Nutr ; 151(4): 1029-1037, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33561214

RESUMO

BACKGROUND: Vitamin A (VA) deficiency is prevalent in preschool-aged children in sub-Saharan Africa. OBJECTIVES: We assessed the effect of small-quantity lipid-based nutrient supplements (SQ-LNS) given to women during pregnancy and lactation and their children from 6 to 18 mo of age on women's plasma and milk retinol concentrations in Malawi, and children's plasma retinol concentration in Malawi and Ghana. METHODS: Pregnant women (≤20 wk of gestation) were randomized to receive daily: 1) iron and folic acid (IFA) during pregnancy only; 2) multiple micronutrients (MMN; 800 µg retinol equivalent (RE)/capsule), or 3) SQ-LNS (800 µg RE/20g) during pregnancy and the first 6 mo postpartum. Children of mothers in the SQ-LNS group received SQ-LNS (400 µg RE/20 g) from 6 to 18 mo of age; children of mothers in the IFA and MMN groups received no supplement. Plasma retinol was measured in mothers at ≤20 and 36 wk of gestation and 6 mo postpartum, and in children at 6 and 18 mo of age. Milk retinol was measured at 6 mo postpartum. VA status indicators were compared by group. RESULTS: Among Malawian mothers, geometric mean (95% CI) plasma retinol concentrations at 36 wk of gestation and 6 mo postpartum were 0.97 µmol/L (0.94, 1.01 µmol/L) and 1.35 µmol/L (1.31, 1.39 µmol/L), respectively; geometric mean (95% CI) milk retinol concentration at 6 mo postpartum was 1.04 µmol/L (0.97, 1.13 µmol/L); results did not differ by intervention group. Geometric mean (95% CI) plasma retinol concentrations for Malawian children at 6 and 18 mo of age were 0.78 µmol/L (0.75, 0.81 µmol/L) and 0.81 µmol/L (0.78, 0.85 µmol/L), respectively, and for Ghanaian children they were 0.85 µmol/L (0.82, 0.88 µmol/L) and 0.88 µmol/L (0.85, 0.91 µmol/L), respectively; results did not differ by intervention group in either setting. CONCLUSIONS: SQ-LNS had no effect on VA status of mothers or children, possibly because of low responsiveness of the VA status indicators.


Assuntos
Suplementos Nutricionais , Lipídeos/administração & dosagem , Leite Humano/metabolismo , Vitamina A/sangue , Vitamina A/metabolismo , Adolescente , Adulto , Feminino , Gana/epidemiologia , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Lactação , Malaui/epidemiologia , Fenômenos Fisiológicos da Nutrição Materna , Mães , Estado Nutricional , Gravidez , Prevalência , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/dietoterapia , Deficiência de Vitamina A/epidemiologia , Adulto Jovem
18.
Public Health Nutr ; 24(10): 3049-3057, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33054890

RESUMO

OBJECTIVES: Inadequate iodine intake during pregnancy increases the risk of neonatal morbidity and mortality. We aimed to evaluate whether prenatal supplements containing iodine affect urinary iodine concentrations (UIC) of pregnant women in Malawi. DESIGN: A randomised controlled trial. Pregnant women (n 1391) were assigned to consume 60 mg/d Fe and 400 µg/d folic acid (IFA) or 18 vitamins and minerals including 250 µg/d iodine (MMN) or 20 g/d small-quantity lipid-based nutrient supplements (SQ-LNS) with similar nutrient contents as MMN group, plus macronutrients (LNS) until childbirth. In a sub-study (n 317), we evaluated group geometric mean urinary iodine concentration (UIC) (µg/L) at 36 weeks of gestation controlling for baseline UIC and compared median (baseline) and geometric mean (36 weeks) UIC with WHO cut-offs: UIC < 150, 150-249, 250-499 and ≥500 reflecting insufficient, adequate, above requirements and excessive iodine intakes, respectively. SETTING: Mangochi District, Malawi. PARTICIPANTS: Women ≤20 weeks pregnant. RESULTS: Groups had comparable background characteristics. At baseline, overall median (Q1, Q3) UIC (319 (167, 559)) suggested iodine intakes above requirements. At 36 weeks, the geometric mean (95 % CI) UIC of the IFA (197 (171, 226)), MMN (212 (185, 243)) and LNS (220 (192, 253)) groups did not differ (P = 0·53) and reflected adequate intakes. CONCLUSIONS: In this setting, provision of supplements containing iodine at the recommended dose to pregnant women with relatively high iodine intakes at baseline, presumably from iodised salt, has no impact on the women's UIC. Regular monitoring of the iodine status of pregnant women in such settings is advisable. Clinicaltrials.gov identifier: NCT01239693.


Assuntos
Ácido Fólico , Iodo , Suplementos Nutricionais , Feminino , Humanos , Recém-Nascido , Ferro , Lipídeos , Malaui , Fenômenos Fisiológicos da Nutrição Materna , Micronutrientes , Gravidez
19.
J Paediatr Child Health ; 57(3): 388-394, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33112481

RESUMO

AIM: This study was designed to determine whether faecal regenerating 1B protein (REG1B) concentration is associated with physical growth among 6-30-month-old children in rural Malawi. METHODS: This was a secondary analysis from a randomised controlled trial in rural Malawi in which we followed-up 790 live-born infants from birth to 30 months of age. We collected anthropometric data at the age of 6, 12, 18, 24 and 30 months. We measured faecal REG1B concentration by enzyme-linked immunosorbent assay (ELISA) technique using stool samples collected at 6, 18 and 30 months of age. We assessed the association between faecal REG1B concentration and children's physical growth using linear regression and longitudinal data analysis. RESULTS: Of 790 live-born infants enrolled, 694 (87%) with at least one faecal REG1B concentration measurement were included in the analysis. Faecal REG1B concentration was not associated with the children's concurrent length-for-age z-score (LAZ), weight-for-age z-score (WAZ), weight-for-length z-score (WLZ) and mid-upper arm circumference-for-age z-score (MUACZ) at any time point (P > 0.05), nor with a change in their anthropometric indices in the subsequent 6-month period (P > 0.05). CONCLUSIONS: Faecal REG1B concentration is not associated with LAZ, WAZ, WLZ and MUACZ among 6-30-month-old infants and children in rural Malawi.


Assuntos
Estatura , Litostatina , População Rural , Antropometria , Peso Corporal , Criança , Pré-Escolar , Fezes , Feminino , Crescimento , Humanos , Lactente , Malaui , Masculino , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Am J Clin Nutr ; 113(2): 380-390, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33381802

RESUMO

BACKGROUND: Insulin-like growth factor I (IGF-I) is the most important hormonal promoter of linear growth in infants and young children. OBJECTIVES: The objectives of this study were to compare plasma IGF-I concentration in a low- compared with a high-income country and characterize biological pathways leading to reduced IGF-I concentration in children in a low-income setting. METHODS: We analyzed plasma IGF-I concentration from 716 Malawian and 80 Finnish children at 6-36 mo of age. In the Malawian children, we studied the association between IGF-I concentration and their environmental exposures; nutritional status; systemic and intestinal inflammation; malaria parasitemia and viral, bacterial, and parasitic enteric infections; as well as growth at 18 mo of age. We then conducted a pathway analysis to identify direct and indirect associations between these predictors and IGF-I concentration. RESULTS: The mean IGF-I concentrations were similar in Malawi and Finland among 6-mo-old infants. At age 18 mo, the mean ± SD concentration was almost double among the Finns compared with the Malawians [24.2 ± 11.3 compared with 12.5 ± 7.7 ng/mL, age- and sex-adjusted difference in mean (95% CI): 11.8 (9.9, 13.7) ng/mL; P < 0.01]. Among 18-mo-old Malawians, plasma IGF-I concentration was inversely associated with systemic inflammation, malaria parasitemia, and intestinal Shigella, Campylobacter, and enterovirus infection and positively associated with the children's weight-for-length z score (WLZ), female sex, maternal height, mother's education, and dry season. Seasonally, mean plasma IGF-I concentration was highest in June and July and lowest in December and January, coinciding with changes in children's length gain and preceded by ∼2 mo by the changes in their WLZ. CONCLUSIONS: The mean plasma IGF-I concentrations are similar in Malawi and Finland among 6-mo-old infants. Thereafter, mean concentrations rise markedly in Finland but not in Malawi. Systemic inflammation and clinically nonapparent infections are strongly associated with lower plasma IGF-I concentrations in Malawi through direct and indirect pathways.


Assuntos
Biomarcadores/sangue , Biomarcadores/química , Inflamação/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Pré-Escolar , Fezes/química , Finlândia , Humanos , Lactente , Malaui , Estações do Ano
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