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1.
J Acquir Immune Defic Syndr ; 43(1): 107-16, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16885772

ABSTRACT

BACKGROUND: Vitamin A deficiency is common among women in resource-poor countries and is associated with greater mortality during HIV. METHODS: Fourteen thousand one hundred ten mothers were tested for HIV and randomly administered 400,000 IU vitamin A or placebo at less than 96 hours postpartum. The effects of vitamin A and HIV status on mortality, health care utilization, and serum retinol were evaluated. RESULTS: Four thousand four hundred ninety-five (31.9%) mothers tested HIV positive. Mortality at 24 months was 2.3 per 1000 person-years and 38.3 per 1000 person-years in HIV-negative and HIV-positive women, respectively. Vitamin A had no effect on mortality. Tuberculosis was the most common cause of death, and nearly all tuberculosis-associated deaths were among HIV-positive women. Among HIV-positive women, vitamin A had no effect on rates of hospitalization or overall sick clinic visits, but did reduce clinic visits for malaria, cracked and bleeding nipples, pelvic inflammatory disease, and vaginal infection. Among HIV-negative women, serum retinol was responsive to vitamin A, but low serum retinol was rare. Among HIV-positive women, serum retinol was largely unresponsive to vitamin A, and regardless of treatment group, the entire serum retinol distribution was shifted 25% less than that of HIV-negative women 6 weeks after dosing. CONCLUSIONS: Single-dose postpartum vitamin A supplementation had no effect on maternal mortality, perhaps because vitamin A status was adequate in HIV-negative women and apparently unresponsive to supplementation in HIV-positive women.


Subject(s)
HIV Infections/epidemiology , HIV Seronegativity , HIV Seropositivity/epidemiology , Puerperal Disorders/virology , Vitamin A/therapeutic use , Adult , Cause of Death , Dietary Supplements , Female , HIV Infections/complications , HIV Infections/mortality , HIV Seropositivity/mortality , Humans , Morbidity , Pregnancy , Risk Factors , Survival Rate , Tuberculosis/complications , Tuberculosis/mortality , Vitamin A/administration & dosage , Zimbabwe/epidemiology
2.
Am J Clin Nutr ; 84(1): 212-22, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16825698

ABSTRACT

BACKGROUND: Anemia is prevalent in infants in developing countries. Its etiology is multifactorial and includes vitamin A deficiency. OBJECTIVE: Our primary aim was to measure the effect of maternal or neonatal vitamin A supplementation (or both) on hemoglobin and anemia in Zimbabwean infants. Our secondary aim was to identify the underlying causes of postnatal anemia. DESIGN: A randomized, placebo-controlled trial was conducted in 14 110 mothers and their infants; 2854 infants were randomly selected for the anemia substudy, of whom 1592 were successfully observed for 8-14 mo and formed the study sample. Infants were randomly assigned within 96 h of delivery to 1 of 4 treatment groups: mothers and infants received vitamin A; mothers received vitamin A and infants received placebo; mothers received placebo and infants received vitamin A; and mothers and infants received placebo. The vitamin A doses were 400,000 and 50,000 IU in the mothers and infants, respectively. RESULTS: Vitamin A supplementation had no effect on hemoglobin or anemia (hemoglobin <105 g/L) in unadjusted or adjusted analyses. Infant HIV infection independently increased anemia risk >6-fold. Additional predictors of anemia in HIV-negative and -positive infants were male sex and lower total body iron at birth. In addition, in HIV-positive infants, the risk of anemia increased with early infection, low maternal CD4+ lymphocyte count at recruitment, and frequent morbidity. Six-month plasma ferritin concentrations <12 microg/L were a risk factor in HIV-negative but not in HIV-positive infants. Maternal HIV infection alone did not cause anemia. CONCLUSION: Prevention of infantile anemia should include efforts to increase the birth endowment of iron and prevent HIV infection.


Subject(s)
Anemia/epidemiology , HIV Infections/complications , Infant Nutritional Physiological Phenomena , Maternal Nutritional Physiological Phenomena , Vitamin A Deficiency/epidemiology , Vitamin A/administration & dosage , Adult , Anemia/blood , Anemia/etiology , Dietary Supplements , Dose-Response Relationship, Drug , Double-Blind Method , Female , Ferritins/blood , HIV Infections/blood , Hemoglobins/analysis , Humans , Infant , Infant, Newborn , Male , Nutritional Status , Postpartum Period , Pregnancy , Prospective Studies , Risk Factors , Sex Factors , Vitamin A/blood , Vitamin A Deficiency/etiology , Vitamin A Deficiency/prevention & control , Vitamins/administration & dosage , Vitamins/blood , Zimbabwe/epidemiology
3.
AIDS ; 20(10): 1437-46, 2006 Jun 26.
Article in English | MEDLINE | ID: mdl-16791019

ABSTRACT

OBJECTIVE: To test whether post-partum vitamin A supplementation can reduce incident HIV among post-partum women and identify risk factors for HIV incidence. DESIGN: Randomized, placebo-controlled trial METHODS: Between November 1997 and January 2001, 14,110 women were randomly administered 400,000 IU vitamin A or placebo within 96 h post-partum. HIV incidence was monitored among 9562 HIV-negative women. RESULTS: Cumulative incidence was 3.4% [95% confidence interval (CI), 3.0-3.8] and 6.5% (95% CI, 5.7-7.4) over 12 and 24 months post-partum, respectively. Vitamin A supplementation had no impact on incidence [hazard ratio (HR), 1.08; 95% CI, 0.85-1.38]. However, among 398 women for whom baseline serum retinol was measured, those with levels indicative of deficiency (< 0.7 micromol/l, 9.2% of those measured) were 10.4 (95% CI, 3.0-36.3) times more likely to seroconvert than women with higher concentrations. Furthermore, among women with low serum retinol, vitamin A supplementation tended to be protective against incidence (HR, 0.29; 95% CI, 0.03-2.60; P = 0.26), although not significantly so, perhaps due to limited statistical power. Severe anaemia (haemoglobin < 70 g/l) was associated with a 2.7-fold (95%CI, 1.2-6.1) greater incidence. Younger women were at higher risk of HIV infection: incidence declined by 5.7% (2.8-8.6) with each additional year of age. CONCLUSION: Among post-partum women, a single large-dose vitamin A supplementation had no effect on incidence, although low serum retinol was a risk factor for seroconversion. Further investigation is required to determine whether vitamin A supplementation of vitamin-A-deficient women or treatment of anaemic women can reduce HIV incidence.


Subject(s)
HIV Infections/prevention & control , Postnatal Care/methods , Vitamin A/therapeutic use , Adolescent , Adult , Age Factors , Female , HIV Infections/epidemiology , Hemoglobins/metabolism , Humans , Incidence , Marital Status , Occupations/statistics & numerical data , Parity , Pregnancy , Risk Factors , Sexual Behavior , Socioeconomic Factors , Vitamin A/blood , Zimbabwe/epidemiology
4.
J Infect Dis ; 193(6): 860-71, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16479521

ABSTRACT

BACKGROUND: Low maternal serum retinol level is a risk factor for mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV). Multiple-large-dose vitamin A supplementation of HIV-positive children reduces mortality. The World Health Organization recommends single-large-dose vitamin A supplementation for postpartum women in areas of prevalent vitamin A deficiency; neonatal dosing is under consideration. We investigated the effect that single-large-dose maternal/neonatal vitamin A supplementation has on MTCT, HIV-free survival, and mortality in HIV-exposed infants. METHODS: A total of 14,110 mother-infant pairs were enrolled < or =96 h after delivery, and both mother and infant, mother only, infant only, or neither received vitamin A supplementation in a randomized, placebo-controlled trial with a 2 x 2 factorial design. All but 4 mothers initiated breast-feeding. A total of 4495 infants born to HIV-positive women were included in the present analysis. RESULTS: Neither maternal nor neonatal vitamin A supplementation significantly affected postnatal MTCT or overall mortality between baseline and 24 months. However, the timing of infant HIV infection modified the effect that supplementation had on mortality. Vitamin A supplementation had no effect in infants who were polymerase chain reaction (PCR) positive [corrected] for HIV at baseline. In infants who were PCR negative at baseline and PCR positive at 6 weeks, neonatal supplementation reduced mortality by 28% (P=.01), but maternal supplementation had no effect. In infants who were PCR negative at 6 weeks, all 3 vitamin A regimens were associated with ~2-fold higher mortality (P< or =.05). CONCLUSIONS: Targeted vitamin A supplementation of HIV-positive children prolongs their survival. However, postpartum maternal and neonatal vitamin A supplementation may hasten progression to death in breast-fed children who are PCR negative at 6 weeks. These findings raise concern about universal maternal or neonatal vitamin A supplementation in HIV-endemic areas.


Subject(s)
HIV Infections/prevention & control , Infant Mortality , Infectious Disease Transmission, Vertical , Vitamin A Deficiency/prevention & control , Vitamin A/administration & dosage , Dietary Supplements , Female , HIV Infections/complications , HIV Infections/mortality , HIV Seronegativity , Humans , Infant , Infant, Newborn , Milk, Human/chemistry , Postpartum Period , Pregnancy , Vitamin A/adverse effects , Vitamin A Deficiency/mortality
5.
BMC Infect Dis ; 6: 1, 2006 Jan 03.
Article in English | MEDLINE | ID: mdl-16390553

ABSTRACT

BACKGROUND: Anemia is common in HIV infection and independently associated with disease progression and mortality. The pathophysiology of HIV-related anemia is not well understood especially in infancy. METHODS: We conducted a longitudinal cohort study nested within the Zimbabwe Vitamin A for Mothers and Babies Project. We measured hemoglobin, erythropoietin (EPO), serum transferrin receptor (TfR) and serum ferritin at 6 weeks, 3 and 6 months of age and hemoglobin at 9 and 12 months in 3 groups of randomly selected infants: 136 born to HIV-negative mothers, and 99 born to HIV-positive mothers and who were infected themselves by 6 weeks of age, and 324 born to HIV-positive mothers but who did not become infected in the 6 months following birth. RESULTS: At one year of age, HIV-positive infants were 5.26 (adjusted odds ratio, P < 0.001) times more likely to be anemic compared to HIV-negative infants. Among, HIV-negative infants, EPO was or tended to be inversely associated with hemoglobin and was significantly positively associated with TfR throughout the first 6 months of life; TfR was significantly inversely associated with ferritin at 6 months; and EPO explained more of the variability in TfR than did ferritin. Among infected infants, the inverse association of EPO to hemoglobin was attenuated during early infancy, but significant at 6 months. Similar to HIV-negative infants, EPO was significantly positively associated with TfR throughout the first 6 months of life. However, the inverse association between TfR and ferritin observed among HIV-negative infants at 6 months was not observed among infected infants. Between birth and 6 months, mean serum ferritin concentration declined sharply (by approximately 90%) in all three groups of babies, but was significantly higher among HIV-positive compared to HIV-negative babies at all time points. CONCLUSION: HIV strongly increases anemia risk and confounds interpretation of hematologic indicators in infants. Among HIV-infected infants, the EPO response to anemia is attenuated near the time of infection in the first weeks of life, but normalizes by 6 months.


Subject(s)
Anemia, Iron-Deficiency/etiology , Anemia, Iron-Deficiency/physiopathology , Erythropoiesis/physiology , HIV Seronegativity/physiology , HIV Seropositivity/complications , HIV Seropositivity/physiopathology , Cohort Studies , Erythropoietin/blood , Female , Ferritins/blood , Hemoglobins/metabolism , Humans , Infant , Infant, Newborn , Longitudinal Studies , Male , Odds Ratio , Receptors, Transferrin/blood , Risk Factors , Zimbabwe
6.
Am J Clin Nutr ; 81(2): 454-60, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15699235

ABSTRACT

BACKGROUND: Young infants are at risk of vitamin A deficiency. Supplementation of breastfeeding mothers improves the vitamin A status of their infants, but there are no data regarding its effect on infant mortality, and data on the effect of directly supplementing infants during the first few weeks of life are conflicting. OBJECTIVE: The objective was to measure the effect on infant mortality of supplementing neonates and their HIV-negative mothers with single, large doses of vitamin A during the immediate postpartum period. DESIGN: A randomized, placebo-controlled, 2-by-2 factorial design trial was conducted in 14,110 mothers and their infants; 9208 of the mothers were HIV-negative at delivery, remained such during the postpartum year, and were retained in the current analysis. The infants were randomly assigned within 96 h of delivery to 1 of 4 treatment groups: mothers and infants received vitamin A (Aa), mothers received vitamin A and infants received placebo (Ap), mothers received placebo and infants received vitamin A (Pa), and both mothers and infants received placebo (Pp). The vitamin A dose in the mothers was 400,000 IU and in the infants was 50,000 IU. The mother-infant pairs were followed to 12 mo. RESULTS: Hazard ratios (95% CI) for 12 mo mortality among infants in the maternal-supplemented and infant-supplemented groups were 1.17 (0.87, 1.58) and 1.08 (0.80, 1.46), respectively. Hazard ratios (95% CI) for the Aa, Ap, and Pa groups compared with the Pp group were 1.28 (0.83, 1.98), 1.27 (0.82, 1.97), and 1.18 (0.76, 1.83), respectively. These data indicate no overall effect. Serum retinol concentrations among a subsample of women were similar to reference norms. CONCLUSION: Postpartum maternal or neonatal vitamin A supplementation may not reduce infant mortality in infants of HIV-negative women with an apparently adequate vitamin A status.


Subject(s)
Infant Mortality , Vitamin A Deficiency/prevention & control , Vitamin A/administration & dosage , Vitamin A/blood , Adult , Dietary Supplements , Double-Blind Method , Female , Follow-Up Studies , HIV Seronegativity , Humans , Infant , Infant Nutrition Disorders/mortality , Infant, Newborn , Infections/mortality , Male , Milk, Human/chemistry , Nutritional Status , Postpartum Period , Vitamin A/analysis , Vitamin A/metabolism , Vitamin A Deficiency/complications , Vitamin A Deficiency/mortality , Zimbabwe/epidemiology
7.
J Nutr ; 133(11): 3461-8, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14608059

ABSTRACT

One method of preventing postnatal iron deficiency is to ensure that the infant is born with a full endowment of iron. We calculated total body iron at birth (TBI) as the sum of hemoglobin iron (HbI) and body storage iron (BSI) in 2021 Zimbabwean newborns, and related TBI to subsequent anemia from 3 to 12 mo of age and to maternal and fetal characteristics. We estimated the mean +/- SD TBI to be 210 +/- 41 mg. There was an inverse dose-response association between TBI quartile and risk of anemia at all postnatal ages. The odds of anemia were >3 times higher in the lowest vs. highest TBI quartile (P < 0.001) at 6, 9 and 12 mo. Preterm birth and parity were not independently associated with TBI after controlling for birthweight. The predicted change in TBI per kilogram increase in birthweight was 68 mg (P < 0.001). After adjusting for birthweight, TBI increased by 25 mg with each 10-y decrement in maternal age (P = 0.033). Maternal hemoglobin was a strong linear predictor of TBI (P < 0.001). Maternal and infant HIV infection, especially among girls, was associated with apparently greater estimated TBI. We speculate that this is actually an artifact, explained by an inflammatory response, and that there was a sex difference in the response. We conclude that we can make satisfactory estimates of TBI and that the assumptions required for this approach are sufficiently robust to lead to an acceptable estimate of the prenatally acquired iron endowment. Babies born with low birthweight or to mothers with low hemoglobin are born with less TBI, which confers a substantially greater risk of anemia from 3 to 12 mo of age.


Subject(s)
Anemia/epidemiology , HIV Seronegativity/physiology , HIV Seropositivity/physiopathology , Hemoglobins/metabolism , Iron/analysis , Child, Preschool , Female , Ferritins/metabolism , Humans , Infant , Male , Mothers , Risk Factors , Zimbabwe
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