RESUMO
BACKGROUND: Vitamin A (VA) assessment is important for targeting public health programs. Retinol isotope dilution (RID) is a sensitive method to estimate total body VA stores (TBSs) and total liver reserves (TLRs), but the impact of subclinical inflammation on RID is unclear. OBJECTIVE: We determined the association between TBSs and TLRs, estimated by RID, and inflammation among preschool children without clinical infection in Burkina Faso, Cameroon, Ethiopia, South Africa, and Tanzania. METHODS: Five studies (n = 532; 47.9 ± 8.3 mo; 49.0% male) included 13C-RID and measurement of inflammation markers, CRP, and α1-acid glycoprotein (AGP). Spearman correlations were used to evaluate TBSs and TLRs with inflammation biomarkers. Wilcoxon and Kruskal-Wallis tests were used to compare TBSs and TLRs by inflammation categories [normal vs. elevated CRP (>5 mg/L) or AGP (>1 g/L)] and inflammation stage [reference, incubation (elevated CRP), early convalescence (elevated CRP and AGP), and late convalescence (elevated AGP)]. RESULTS: Complete data were available for 439 children. Median (Q1, Q3) TLRs ranged from 0.12 (0.07, 0.18) µmol/g in Ethiopia to 1.10 (0.88, 1.38) µmol/g in South Africa. Elevated CRP ranged from 4% in Burkina Faso to 42% in Cameroon, and elevated AGP from 20% in Tanzania to 58% in Cameroon. Pooled analysis (excluding Cameroon) showed a negative correlation between TBSs and AGP (ρ = -0.131, P = 0.01). Children with elevated AGP had higher probability of having lower TBSs (probability = 0.61, P = 0.002). TBSs differed among infection stages (P = 0.020). Correlations between TLRs and CRP or AGP were not significant. CONCLUSIONS: No indication of systematic bias in RID-estimated TLRs was found due to subclinical inflammation among preschool children. The inverse relationship between TBSs and AGP may reflect decreased stores after infection or an effect of inflammation on isotope partitioning. Further research should investigate potential confounding variables to improve TBS-estimate validity.
Assuntos
Deficiência de Vitamina A , Vitamina A , Humanos , Masculino , Pré-Escolar , Feminino , Convalescença , Inflamação , Biomarcadores , Fígado/química , Isótopos , África do Sul , Orosomucoide/análiseRESUMO
BACKGROUND: Stable isotope techniques using 13C to assess vitamin A (VA) dietary sources, absorption, and total body VA stores (TBSs) require determination of baseline 13C abundance. 13C-natural abundance is approximately 1.1% total carbon, but varies with foods consumed, supplements taken, and food fortification with synthetic retinyl palmitate. OBJECTIVES: We determined 13C variation from purified serum retinol and the resulting impact on TBSs using pooled data from preschool children in Burkina Faso, Cameroon, Ethiopia, South Africa, Tanzania, and Zambia and Zambian women. METHODS: Seven studies included children (n = 639; 56 ± 25 mo; 48% female) and one in women (n = 138; 29 ± 8.5 y). Serum retinol 13C-natural abundance was determined using GC-C-IRMS. TBSs were available in 7 studies that employed retinol isotope dilution (RID). Serum CRP and α1-acid-glycoprotein (AGP) were available from 6 studies in children. Multivariate mixed models assessed the impact of covariates on retinol 13C. Spearman correlations and Bland-Altman analysis compared serum and milk retinol 13C and evaluated the impact of using study- or global-retinol 13C estimates on calculated TBSs. RESULTS: 13C-natural abundance (%, median [Q1, Q3]) differed among countries (low: Zambia, 1.0744 [1.0736, 1.0753]; high: South Africa, 1.0773 [1.0769, 1.0779]) and was associated with TBSs, CRP, and AGP in children and with TBSs in women. 13C-enrichment from serum and milk retinol were correlated (r = 0.52; P = 0.0001). RID in children and women using study and global estimates had low mean bias (range, -3.7% to 2.2%), but larger 95% limits of agreement (range, -23% to 37%). CONCLUSIONS: 13C-natural abundance is different among human cohorts in Africa. Collecting this information in subgroups is recommended for surveys using RID. When TBSs are needed on individuals in clinical applications, baseline 13C measures are important and should be measured in all enrolled subjects.
Assuntos
Deficiência de Vitamina A , Vitamina A , Humanos , Feminino , Pré-Escolar , Masculino , Dieta , Deficiência de Vitamina A/epidemiologia , Suplementos Nutricionais , Isótopos , ZâmbiaRESUMO
Previous research has demonstrated a virtual absence of vitamin A deficiency and adequacy of vitamin A intake through consumption of liver in preschool children of a community in the Northern Cape province of South Africa where sheep farming is common, and liver, an exceptionally rich source of vitamin A, is frequently eaten. Only 60-75 g of liver per month is needed to meet the vitamin A requirement of preschool children. Because this may have implications for routine vitamin A supplementation, and because liver consumption for the rest of the province is unknown, the study aim was to establish the prevalence and frequency of liver intake in a provincial-wide survey. An unquantified liver-specific food frequency questionnaire, covering a period of 1 month, complemented by a 1-year recall, was administered to mothers of 2- to 5-year-old children (n = 2,864) attending primary health care facilities in all five districts and 26 subdistricts. A total of 86% of children were reported to eat liver, which was eaten in all districts by at least 80% of children. The overall median frequency of liver intake was 1.0 [25th, 75th percentiles: 0.5, 3.0] times per month and ranged from 1.0 [0.3, 2.0] to 2.0 [1.0, 4.0] for the various districts. Based on a previously reported portion size of 66 g, these results suggest vitamin A dietary adequacy in all districts and possibly also vitamin A intake exceeding the Tolerable Upper Intake Level in some children. Routine vitamin A supplementation in this province may not be necessary and should be reconsidered.
Assuntos
Dieta/métodos , Carne , Inquéritos Nutricionais/estatística & dados numéricos , Estado Nutricional , Deficiência de Vitamina A/prevenção & controle , Vitamina A/sangue , Animais , Pré-Escolar , Feminino , Humanos , Fígado , Masculino , Inquéritos Nutricionais/métodos , Ovinos , África do SulRESUMO
Serum retinol was assessed in mothers and newborns from an impoverished South African community where liver is frequently eaten and vitamin A deficiency known to be absent. Paired cord and maternal blood (n = 201) were collected after delivery and analysed for serum retinol and C-reactive protein (CRP). Liver intake during pregnancy and intention to breastfeed were also assessed. Mean serum retinol was 1.03 µmol/L ± 0.40 in mothers and 0.73 ± 0.24 µmol/L in newborns, with 21.4% and 49.3% having serum retinol <0.70 µmol/L (<20 µg/dL), respectively. Raised CRP was found in 59.9% of mothers, with a significant negative correlation between serum retinol and CRP (r = -0.273; p < 0.0001). Liver was eaten by 87.6% of mothers, and 99% indicated their intention to breastfeed. Despite consumption of liver, serum retinol was low in both the mother and the newborn. The conventional cut-off for serum retinol, i.e. <0.70 µmol/L may therefore not apply for the mother and newborn in the period immediately after delivery. Serum retinol may be influenced by factors other than vitamin A status, e.g. the haemodilution of pregnancy, as well as the acute phase response induced by the birth process, as suggested by raised CRP in 60% of mothers. In the newborns, the low serum retinol is likely to increase rapidly, as liver is frequently eaten by mothers and practically all of them intended to breastfeed. Our results confirm the need for better indicators of vitamin A status or alternative cut-off values during this period.
Assuntos
Carne , Mães , Período Pós-Parto/sangue , Deficiência de Vitamina A/epidemiologia , Vitamina A/sangue , Adulto , Aleitamento Materno , Proteína C-Reativa/metabolismo , Dieta , Feminino , Sangue Fetal/química , Humanos , Recém-Nascido , Fígado , Estado Nutricional , Fatores Socioeconômicos , África do Sul , Inquéritos e Questionários , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/diagnóstico , Adulto JovemRESUMO
OBJECTIVE: To assess the contribution of liver to the vitamin A intake of 24-59-month-old children from an impoverished South African community where liver is frequently consumed and vitamin A deficiency previously shown to be absent. DESIGN: Cross-sectional. SETTING: Northern Cape Province, South Africa. SUBJECTS: Children aged 24-59 months (n 150). Vitamin A intake from liver was assessed using a single 24 h recall and a quantified liver frequency questionnaire. In addition, information on vitamin A intake via the national fortification programme was obtained from the 24 h recall and information on vitamin A supplementation from the Road-to-Health Chart. Height, weight and socio-economic data were also collected. RESULTS: Stunting, underweight and wasting were prevalent in 36·9 %, 25·5 % and 12·1 % of children. Mean daily vitamin A intake from liver was 537 and 325 µg retinol equivalents measured by the 24 h recall and liver frequency questionnaire, respectively. Liver was consumed in 92·7 % of households and by 84·7 % of children; liver intake was inversely related to socio-economic status (P < 0·05). The food fortification programme contributed 80 µg retinol equivalents and the vitamin A supplementation programme 122 µg retinol equivalents to daily vitamin A intake. CONCLUSIONS: The study showed that liver alone provided more than 100 % of the Estimated Average Requirement of the pre-school children in this impoverished community. The results also challenge the notion generally held by international health bodies that vitamin A deficiency, poor anthropometric status and poverty go together, and reinforces the fact that South Africa is a culturally diverse society for which targeted interventions are required.
Assuntos
Dieta , Fígado , Carne , Necessidades Nutricionais , Pobreza , Deficiência de Vitamina A/prevenção & controle , Vitamina A/administração & dosagem , Adulto , Pré-Escolar , Estudos Transversais , Suplementos Nutricionais , Características da Família , Feminino , Alimentos Fortificados , Transtornos do Crescimento/epidemiologia , Humanos , Masculino , Rememoração Mental , Avaliação Nutricional , Classe Social , África do Sul/epidemiologia , Inquéritos e Questionários , Magreza/epidemiologia , Síndrome de Emaciação/epidemiologiaAssuntos
Saúde Global , Saúde Mental/estatística & dados numéricos , Humanos , Transtornos Mentais/economia , Transtornos Mentais/epidemiologia , Transtornos Mentais/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias/economia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Organização Mundial da SaúdeRESUMO
OBJECTIVE: To assess serum retinol, liver intake patterns, breast-feeding history and anthropometric status in pre-school children of a low socio-economic community where liver is regularly consumed. DESIGN: Cross-sectional study. SETTING: Northern Cape Province, South Africa. SUBJECTS: Children aged 1-6 years (n 243) who attended the local primary health-care facility and had not received a vitamin A supplement in the 6 months preceding the study. Non-pregnant female caregivers (n 225), below 50 years of age, were also assessed. RESULTS: Despite stunting, underweight and wasting being prevalent in 40·5%, 23·1% and 8·4% of the children, only 5·8% had serum retinol concentrations < 20 µg/dl, which is in sharp contrast to the national prevalence of 63·6%. None of the caregivers were vitamin A deficient. Liver was eaten by 89·2% of children, with 87% of households eating liver at least once monthly and 30% eating it at least once weekly; liver was introduced into the diet of the children at a median age of 18 months. Ninety-three per cent of the children were being breast-fed or had been breast-fed in the past; children were breast-fed to a median age of 18 months. A significant negative correlation was found between educational level of the caregiver and frequency of liver intake (r = -0·143, P=0·032). There was no correlation between serum retinol and indicators of anthropometric or socio-economic status. CONCLUSIONS: The blanket approach in applying the national vitamin A supplementation programme may not be appropriate for all areas in the country, even though the community may be poor and undernourished.
Assuntos
Antropometria , Transtornos da Nutrição Infantil/epidemiologia , Fígado , Vitamina A/administração & dosagem , Vitamina A/sangue , Aleitamento Materno/estatística & dados numéricos , Criança , Transtornos da Nutrição Infantil/sangue , Pré-Escolar , Estudos Transversais , Suplementos Nutricionais , Feminino , Humanos , Lactente , Masculino , Fatores Socioeconômicos , África do Sul/epidemiologia , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/epidemiologiaRESUMO
BACKGROUND: Excessive vitamin A (VA) can cause bone resorption and impair growth. Government-mandated VA supplementation (VAS) and adequate intake through dietary fortification and liver consumption led to excessive VA in South African children. OBJECTIVES: We evaluated the relation between VAS and underlying hypervitaminosis A assessed by retinol isotope dilution (RID) with measures of growth and bone turnover in this cohort. METHODS: Primary outcomes in these children (n = 94, 36-60 mo) were anthropometric measurements [height-for-age (HAZ), weight-for-age (WAZ), and weight-for-height (WHZ) z scores], serum bone turnover markers [C-terminal telopeptide of type I collagen (CTX) and N-terminal propeptide of type I procollagen (P1NP)], and inflammation defined as C-reactive protein (CRP; ≥5 mg/L) and/or α1-acid glycoprotein (AGP; ≥1 g/L). VA status was previously measured by RID-estimated total body VA stores (TBSs) and total liver VA reserves (TLRs), and serum retinol and carotenoid concentrations, before and 4 wk after children were administered 200,000 IU VAS. Serum 25-hydroxyvitamin D3 was measured by ultra-performance LC. RESULTS: In this largely hypervitaminotic A cohort, HAZ, WAZ, and WHZ were negatively associated with increasing TLRs, where TLRs predicted 6-10% of the variation before VAS (P < 0.05), increasing to 14-19% 4 wk after VAS (P < 0.01). Bone resorption decreased after VAS (P < 0.0001), whereas formation was unaffected. Neither CTX nor P1NP were correlated with TLRs at either time. Serum carotenoids were low. One child at each time point was vitamin D deficient (<50 nmol/L). CRP and AGP were not associated with growth measurements. CONCLUSIONS: Excessive TLRs due to dietary VA intake and VAS are associated with lower anthropometric measures and bone resorption decreased after supplementation. VA supplementation programs should monitor VA status with biomarkers sensitive to TLRs to avoid causing negative consequences in children with hypervitaminosis A. This trial is registered at clinicaltrials.gov as NCT02915731.
Assuntos
Hipervitaminose A , Deficiência de Vitamina A , Pré-Escolar , Dieta , Humanos , África do Sul , Vitamina ARESUMO
PURPOSE: In this study, we aimed to investigate trends in the age-standardized and age-specific incidence rates in two distinct regions (the northern and southern areas) of South Africa covered by a population-based cancer registry. In addition, trends in coverage of the cervical cancer screening program were assessed using routine health service data. METHODS: Occurrences (topography C53.0-C53.9) for the period 1998-2012 were extracted from a cancer registry database from which basic descriptive statistics and frequencies were analyzed for all variables using CanReg4. Trends over time were estimated using a direct standardization method and world standard population as a reference. Screening coverage annualized figures for women age ≥ 30 years by sub-health district were extracted from the District Health Information System. RESULTS: In the northern area, annual age-standardized incidence rates per 100,000 women increased from 24.0 (95% CI, 21.1 to 27.0) in 1998-2002 to 39.0 (95% CI, 35.6 to 42.5) in 2008-2012, with a screening coverage rate of 15% by 2012. In contrast, no increase was observed in incidence in the southern area, with rates of 20.0 (95% CI, 18.5 to 21.4) in 1998-2002 and 18.8 (95% CI, 16.2 to 21.4) in 2008-2012, and the southern area had a higher screening coverage of 41% in 2012. Overall, the percentage distribution of stage at diagnosis showed that 28.5% of occurrences were diagnosed at disease stages I and II and 35%, at III and IV; 36% had with missing stage information (2003-2012). In 77% of occurrences, a histologically verified diagnosis was made, compared with only 12.3% by cytology. CONCLUSION: This study has demonstrated an almost two-fold increase in the incidence rate in the northern area but little change in the southern area of the cancer registry.
Assuntos
Neoplasias do Colo do Útero , Adulto , Detecção Precoce de Câncer , Feminino , Humanos , Incidência , Sistema de Registros , África do Sul/epidemiologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologiaRESUMO
Vitamin A (VA) deficiency is a serious public health problem, especially in preschool children who are at risk of increased mortality. In order to address this problem, the World Health Organization recommends periodic high-dose supplementation to children 6-59 months of age in areas of highest risk. Originally, supplementation was meant as a short-term solution until more sustainable interventions could be adopted. Currently, many countries are fortifying commercialized common staple and snack foods with retinyl palmitate. However, in some countries, overlapping programs may lead to excessive intakes. Our review uses case studies in the United States, Guatemala, Zambia, and South Africa to illustrate the potential for excessive intakes in some groups. For example, direct liver analysis from 27 U.S. adult cadavers revealed 33% prevalence of hypervitaminosis A (defined as ≥1 µmol/g liver). In 133 Zambian children, 59% were diagnosed with hypervitaminosis A using a retinol isotope dilution, and 16% had ≥5% total serum VA as retinyl esters, a measure of intoxication. In 40 South African children who frequently consumed liver, 72.5% had ≥5% total serum VA as retinyl esters. All four countries have mandatory fortified foods and a high percentage of supplement users or targeted supplementation to preschool children.
Assuntos
Vitamina A/administração & dosagem , Pré-Escolar , Suplementos Nutricionais , Feminino , Guatemala/epidemiologia , Humanos , Hipervitaminose A/epidemiologia , Lactente , Masculino , África do Sul/epidemiologia , Estados Unidos/epidemiologia , Deficiência de Vitamina A/epidemiologia , Zâmbia/epidemiologiaRESUMO
BACKGROUND: In some regions, multiple vitamin A (VA) interventions occur in the same target groups, which may lead to excessive stores. Retinol isotope dilution (RID) is a more sensitive technique than serum retinol to measure VA status. OBJECTIVE: We evaluated VA status before and after a high-dose supplement in preschool children living in a region in South Africa with habitual liver consumption and exposed to VA supplementation and fortification. METHODS: After baseline blood samples, subjects (46.7 ± 8.4 mo; n = 94) were administered 1.0 µmol [14,15]-13C2-retinyl acetate to estimate total liver retinol reserves by RID with a follow-up 14-d blood sample. Liver intake was assessed with a frequency questionnaire. In line with current practice, a routine 200,000 IU VA capsule was administered after the RID test. RID was repeated 1 mo later. Serum retinyl esters were evaluated using ultra-performance liquid chromatography. RESULTS: At baseline, 63.6% of these children had hypervitaminosis A defined as total liver retinol reserves ≥1.0 µmol/g liver, which increased to 71.6% after supplementation (1.13 ± 0.43 to 1.29 ± 0.46 µmol/g; P < 0.001). Total serum VA as retinyl esters was elevated in 4.8% and 6.1% of children before and after supplementation. The odds of having hypervitaminosis A at baseline were higher in children consuming liver ≥1/mo (ratio 3.70 [95% CI: 1.08, 12.6]) and in children receiving 2 (4.28 [1.03, 17.9]) or 3 (6.45 [0.64, 65.41]) supplements in the past 12 mo. Total body stores decreased after the supplement in children in the highest quartile at baseline compared with children with lower stores, who showed an increase (P = 0.007). CONCLUSIONS: In children, such as this cohort in South Africa, with adequate VA intake through diet, and overlapping VA fortification and supplementation, preschool VA capsule distribution should be re-evaluated. This trial was registered at https://clinicaltrials.gov/ct2/show/NCT02915731 as NCT02915731.
Assuntos
Dieta , Alimentos Fortificados , Hipervitaminose A/sangue , Fígado , Ovinos , Vitamina A/administração & dosagem , Animais , Pré-Escolar , Suplementos Nutricionais , Alimentos Fortificados/análise , Humanos , Fígado/química , África do Sul , Vitamina A/análise , Vitamina A/sangueRESUMO
The choice of iron fortificant usually represents a balance between bioavailability of the compound and its tendency to cause organoleptic problems. The aim of this study was to evaluate the efficacy of sodium iron EDTA (NaFeEDTA) and ferrous fumarate at levels compatible with South African brown bread (10 mg/kg flour for NaFeEDTA and 20 mg/kg flour for ferrous fumarate) in a randomized controlled trial; electrolytic iron was evaluated at the level currently used in South Africa (35 mg/kg flour). Schoolchildren (n = 361), aged 6-11 y, from a low socioeconomic community with hemoglobin (Hb) < or = 125 g/L were randomly assigned to 1 of 4 groups that received 4 slices of brown bread supplying either: 1) no fortification iron 2) 2.35 mg iron as NaFeEDTA; 3) 4.70 mg iron as ferrous fumarate; and 4) 8.30 mg iron as electrolytic iron per intervention day. These amounts simulated a bread intake of 6 slices per day over the 34-wk study period at fortification levels of 0, 10, 20, and 35 mg/kg flour, respectively. Hb concentration and iron status were assessed at baseline and after 34 wk of intervention. The iron interventions did not affect Hb concentration, transferrin saturation, or serum ferritin, iron, or transferrin receptor concentrations relative to the control group. Our results suggest that electrolytic iron at the level currently used in South Africa is not effective in improving iron or Hb status. Neither do NaFeEDTA or ferrous fumarate appear to be suitable alternatives for the fortification of wheat flour when included at levels that do not cause color changes.
Assuntos
Anemia Ferropriva/prevenção & controle , Pão/análise , Compostos Férricos/administração & dosagem , Compostos Ferrosos/administração & dosagem , Alimentos Fortificados/análise , Ferro/administração & dosagem , Criança , Relação Dose-Resposta a Droga , Ácido Edético/administração & dosagem , Ácido Edético/química , Compostos Férricos/química , Compostos Ferrosos/química , Hemoglobinas/metabolismo , Humanos , Ferro/sangue , Ferro/química , África do SulRESUMO
The ratio of Ascaris seropositivity to the presence of eggs in the faeces was 2.44 in children residing near Cape Town, South Africa. Similar and larger ratios have previously been described for children and women living in the city. The new finding strengthens the concept that when helminthic infections occur together with non-helminthic diseases, an analysis of the interaction must include the use of disease-related immunological variables and not be based only on egg excretion status. One of the reasons is that many egg-negative people who live where helminthiasis is highly endemic are immunologically activated as a result of transitory non-patent or intermittent patent infection by Ascaris and/or other worms.
Assuntos
Ascaríase/complicações , Ascaríase/imunologia , Ascaris/imunologia , Adolescente , Animais , Criança , Feminino , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Imunoglobulina E/sangue , Contagem de Ovos de Parasitas/normas , Prevalência , África do SulRESUMO
BACKGROUND: Ascariasis and HIV/AIDS are often co-endemic under conditions of poverty in South Africa; and discordant immune responses to the respective infections could theoretically be affecting the epidemic of HIV/AIDS in various ways. It is well-known that sensitisation to helminthic antigens can aggravate or ameliorate several non-helminthic diseases and impair immunisation against cholera, tetanus and tuberculosis. The human genotype can influence immune responses to Ascaris strongly. With these factors in mind, we have started to document the extent of long-term exposure to Ascaris and other helminths in a community where HIV/AIDS is highly prevalent. In more advanced studies, objectives are to analyse relevant immunological variables (e.g. cytokine activity and immunoglobulin levels). We postulate that when Ascaris is hyperendemic, analysis of possible consequences of co-infection by HIV cannot be based primarily on excretion vs non-excretion of eggs. METHODS: Recall of worms seen in faeces was documented in relation to the age of adult volunteers who were either seropositive (n = 170) or seronegative (n = 65) for HIV. Reasons for HIV testing, deworming treatments used or not used, date and place of birth, and duration of residence in Cape Town, were recorded. Confidence intervals were calculated both for group percentages and the inter-group differences, and were used to make statistical comparisons. RESULTS: In both groups, more than 70% of participants were aware of having passed worms, often both when a child and as an adult. Most of the descriptions fitted Ascaris. Evidence for significantly prolonged exposure to helminthic infection in HIV-positives was supported by more recall of deworming treatment in this group (p < 0.05). Over 90% of the participants had moved to the city from rural areas. CONCLUSION: There was a long-term history of ascariasis (and probably other helminthic infections) in both of the groups that were studied. In women in the same community, and in children living where housing and sanitation are better, Ascaris sero-prevalence exceeded egg-prevalence by two- and three-fold, respectively. For ongoing and future analyses of possible consequences of co-infection by Ascaris (and/or other helminths) and HIV/AIDS (and/or other bystander conditions), comparisons must be based mainly on disease-related immunological variables. Especially in adults, comparisons cannot be based only on the presence or absence of eggs in excreta.
Assuntos
Fezes/parasitologia , Infecções por HIV/complicações , Helmintíase/complicações , Enteropatias Parasitárias/complicações , Adulto , Animais , Anti-Helmínticos/uso terapêutico , Ascaríase/complicações , Ascaríase/tratamento farmacológico , Ascaríase/parasitologia , Ascaris/isolamento & purificação , Criança , Feminino , Helmintíase/tratamento farmacológico , Helmintíase/parasitologia , Humanos , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/parasitologia , Masculino , Contagem de Ovos de Parasitas , África do Sul , Inquéritos e QuestionáriosRESUMO
Adequate iodine concentration in breastmilk (BMIC) is essential for optimal neonatal thyroid hormone synthesis and neurological development in breastfed infants. For many decades, iodine deficiency has been a public health problem in Nepal. However, recently, excessive iodine intakes among Nepali infants have been reported. This study aimed to measure BMIC and urinary iodine concentration (UIC) among lactating women in a peri-urban area of Nepal. Iodine concentration was measured in spot urine (n = 485) and breastmilk samples (n = 291) of 500 randomly selected lactating women. The median (p25, p75) BMIC and median UIC were 250 (130, 370) µg/L and 230 (135-377) µg/L, respectively. Around 82% had BMIC > 100 µg/L, 61% had BMIC > 200 µg/L and 81% had UIC > 100 µg/L, 37% had >300 µg/L and 20% had >500 µg/L. In multiple linear regression models, time since birth (ß 3.0, 95% CI (0.2, 5.0)) and UIC (ß 1.0, 95% CI (0.1, 2.0)) were associated with BMIC, explaining 26% of the variance. A large proportion of the women had adequate BMIC and UIC; however, a subset had high iodine concentrations. These findings emphasize the importance of carefully monitoring iodine intake to minimize the risk of iodine excess and subsequently preventing transient iodine-induced hypothyroidism in breastfed infants.
Assuntos
Iodo/análise , Iodo/urina , Lactação/fisiologia , Leite Humano/química , Feminino , Humanos , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/epidemiologia , Lactente , Iodo/efeitos adversos , NepalRESUMO
BACKGROUND: South Africa has endorsed a World Health Assembly (WHA) resolution calling for control of soil-transmitted helminths (STHs). In Cape Town, services and housing that exist in old-established suburbs should minimise the prevalence of intestinal parasitic infections, even when residents are poor. Where families live in shacks in densely-populated areas without effective sanitation, more than 90% of children can be infected by STHs. The humoral immune response to worms theoretically favours infection by Mycobacterium tuberculosis and HIV. OBJECTIVES: Obtain estimates of gender-, age-, school-related and overall prevalence of helminthiasis and giardiasis in a low-income but well-serviced community. Assess possible sources of infection. Alert health services to the need for control measures and the threat from protozoal pathogens. Warn that the immune response to intestinal parasites may favour tuberculosis (TB) and HIV/AIDS. METHODS: A cross-sectional study of the prevalence of helminthiasis and giardiasis was carried out in a large, non-selective sample of children attending nine schools. Gender, school and age effects were related to non-medical preventive services, sewage disposal practices and possible sources of infection. RESULTS: The overall STH infestation rate was 55.8%. Prevalence was influenced by school and age but not by gender. Eggs and cysts were seen at the following prevalences: Ascaris 24.8%; Trichuris 50.6%; Hymenolepis nana 2.2%; Enterobius 0.6%; Giardia 17.3%; hookworm 0.08%; and Trichostrongylus 0.1%. Approximately 60% of sewage sludge is used in a form that will contain viable eggs and cysts. CONCLUSIONS: Prevalence trends in this old community in Cape Town could indicate infection by swallowing eggs or cysts on food or in water, more than by exposure to polluted soil. Sewage sludge and effluent might be sources of infection. In adjacent, under-serviced, newer communities, promiscuous defaecation occurs. Probable vectors are discussed. The immune response to intestinal parasites might be a risk factor for HIV/AIDS and TB.
Assuntos
Giardíase/epidemiologia , Helmintíase/epidemiologia , Adolescente , Fatores Etários , Criança , Estudos Transversais , Feminino , Giardíase/prevenção & controle , Helmintíase/prevenção & controle , Humanos , Masculino , Áreas de Pobreza , Prevalência , Prevenção Primária , Fatores Sexuais , África do Sul/epidemiologiaRESUMO
OBJECTIVES: This cross-sectional study examined the nutritional factors associated with the high levels of stunting in 2- to 5-y-old children in an impoverished South African setting where liver is frequently eaten and vitamin A deficiency known to be absent. METHODS: Children's dietary intake was assessed by a single 24-h recall. Heights and weights were measured and information was obtained on breast-feeding history, the child's habitual milk intake, as well as substance use by the mother during pregnancy (n = 150). RESULTS: The overall prevalence of stunting was 36.9% (CI 29.2, 44.6) and increased with age, being 49% in the 4- to 5-y-old age category. Birth weight correlated significantly with height-for-age z-scores (HAZ; r = 0.250, P = 0.003), and was lower in children whose mothers smoked and used alcohol during pregnancy than in children whose mothers abstained (P < 0.0001). Median intake of energy, carbohydrate and protein was adequate. Median intake for all micronutrients was at least 90% of the estimated average requirement, except for calcium, vitamin D and vitamin E, which was 21%, 15%, and 32%, respectively. Intake of fat, calcium, phosphorous, vitamin D, riboflavin, and vitamin B12 (nutrients that typically occur in milk) was significantly lower in stunted than in non-stunted children (P < 0.05). When excluding children with low birth weight, intake of calcium, vitamin D, and riboflavin were still significantly lower (P < 0.05). HAZ was higher in children who habitually drank milk compared to those who did not (P = 0.003). CONCLUSIONS: Inadequate calcium and vitamin D intake, presumably because of low intake of milk after weaning, may have contributed to stunting in this population.
Assuntos
Cálcio/deficiência , Dieta , Transtornos do Crescimento/etiologia , Micronutrientes/deficiência , Estado Nutricional , Deficiência de Vitamina D/complicações , Vitamina D/administração & dosagem , Animais , Peso ao Nascer , Cálcio/administração & dosagem , Pré-Escolar , Estudos Transversais , Feminino , Transtornos do Crescimento/epidemiologia , Humanos , Ferro/administração & dosagem , Deficiências de Ferro , Masculino , Micronutrientes/administração & dosagem , Gravidez , Complicações na Gravidez , Prevalência , Riboflavina/administração & dosagem , África do Sul/epidemiologia , Vitamina A/administração & dosagem , Deficiência de Vitamina D/epidemiologia , Zinco/administração & dosagem , Zinco/deficiênciaRESUMO
BACKGROUND: Production of yellow and dark-green leafy vegetables at the household level may provide economically deprived households with direct access to provitamin A-rich foods. OBJECTIVE: The aim of the study was to determine whether the dietary intake of yellow and dark-green leafy vegetables and the serum retinol concentrations of children improve with a home-gardening program. DESIGN: A home-gardening program was integrated with a community-based growth-monitoring system in a rural village. Cross-sectional data were collected at baseline and 20 mo after implementation of the program. The dietary intake, serum retinol concentrations, and growth of 2-5-y-old children and maternal knowledge regarding vitamin A were determined. A neighboring village served as a control village. RESULTS: In the experimental village, 126 home gardens were established, representing approximately one-third of the households. Serum retinol concentrations in the experimental village increased significantly (P = 0.0078), whereas those in the control village decreased significantly (P = 0.0148). At follow-up, children from the experimental village consumed yellow and dark-green leafy vegetables more often and had significantly higher (P = 0.005) serum retinol concentrations (0.81 +/- 0.22 micro mol/L; n = 110) than did children from the control village (0.73 +/- 0.19 micro mol/L; n = 111). Maternal knowledge regarding vitamin A improved significantly in the experimental village (P = 0.001). CONCLUSION: A home-gardening program that was integrated with a primary health care activity, linked to nutrition education, and focused on the production of yellow and dark-green leafy vegetables significantly improved the vitamin A status of 2-5-y-old children in a rural village in South Africa.
Assuntos
Agricultura , Verduras , Vitamina A/sangue , Adulto , Cuidadores , Pré-Escolar , Estudos Transversais , Dieta , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , Mães , Estado Nutricional , Concentração Osmolar , População Rural , África do SulRESUMO
BACKGROUND: Low serum concentrations of vitamin A and zinc are common in tuberculosis and may have an adverse effect on host cell-mediated responses. The role of adjunctive micronutrient supplementation on treatment outcomes is uncertain. OBJECTIVE: The objective was to assess the efficacy of vitamin A and zinc supplementation on sputum smear and culture conversion and time to culture detection in adults with sputum smear-positive pulmonary tuberculosis. DESIGN: Participants attending a primary care tuberculosis clinic in Cape Town, South Africa, were randomly assigned to receive micronutrients (single dose of 200,000 IU retinyl palmitate plus 15 mg Zn/d for 8 wk) or matching placebo. Sputum was collected weekly for 8 wk for auramine staining and culture on liquid media (BACTEC MGIT 960; Becton Dickinson, Sparks, MD). Performance status, chest radiographs, and anthropometric measures were assessed at baseline and again at 8 wk. RESULTS: The participants (n = 154) were randomly assigned to the micronutrient (n = 77) or placebo (n = 77) group. Twenty participants were HIV infected (13%), and 12 participants had an unknown HIV status (8%). No differences in time to smear or culture conversion were observed between the treatment groups by Kaplan-Meier analysis (P = 0.15 and P = 0.38, respectively; log-rank test). Log-logistic regression analysis found no significant group interaction effect in time to culture detection over the 8-wk period (P = 0.32). No significant differences in weight gain (2.3 ± 3.5 compared with 2.2 ± 2.4 kg, P = 0.68) or radiologic resolution were observed between the treatment groups. CONCLUSION: Supplementation with vitamin A and zinc did not affect treatment outcomes in participants with pulmonary tuberculosis at 8 wk. This trial was registered at controlled-trials.com as ISRCTN80852505.
Assuntos
Suplementos Nutricionais , Tuberculose Pulmonar/tratamento farmacológico , Vitamina A/administração & dosagem , Zinco/administração & dosagem , Adulto , Proteína C-Reativa/análise , Cobre/sangue , Feminino , Humanos , Masculino , Estado Nutricional , Resultado do Tratamento , Tuberculose Pulmonar/sangue , Vitamina A/sangue , Zinco/sangueRESUMO
OBJECTIVES: To estimate the extent of iron deficiency anaemia (IDA) among children aged 0 - 4 years and pregnant women aged 15 - 49 years, and the burden of disease attributed to IDA in South Africa in 2000. DESIGN: The comparative risk assessment (CRA) methodology of the World Health Organization (WHO) was followed using local prevalence and burden estimates. IDA prevalence came from re-analysis of the South African Vitamin A Consultative Group study in the case of the children, and from a pooled estimate from several studies in the case of the pregnant women (haemoglobin level < 11 g/dl and ferritin level < 12 microg/l). Monte Carlo simulation-modelling was used for the uncertainty analysis. SETTING: South Africa. SUBJECTS: Children under 5 years and pregnant women 15 - 49 years. OUTCOME MEASURES: Direct sequelae of IDA, maternal and perinatal deaths and disability-adjusted life years (DALYs) from mild mental disability related to IDA. Results. It is estimated that 5.1% of children and 9 - 12% of pregnant women had IDA and that about 7.3% of perinatal deaths and 4.9% of maternal deaths were attributed to IDA in 2000. Overall, about 174,976 (95% uncertainty interval 150,344 - 203,961) healthy years of life lost (YLLs), or between 0.9% and 1.3% of all DALYs in South Africa in 2000, were attributable to IDA. CONCLUSIONS: This first study in South Africa to quantify the burden from IDA suggests that it is a less serious public health problem in South Africa than in many other developing countries. Nevertheless, this burden is preventable, and the study highlights the need to disseminate the food-based dietary guidelines formulated by the National Department of Health to people who need them and to monitor the impact of the food fortification programme.