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1.
JCI Insight ; 6(3)2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33400687

RESUMEN

Antiretroviral therapies (ARTs) abrogate HIV replication; however, infection persists as long-lived reservoirs of infected cells with integrated proviruses, which reseed replication if ART is interrupted. A central tenet of our current understanding of this persistence is that infected cells are shielded from immune recognition and elimination through a lack of antigen expression from proviruses. Efforts to cure HIV infection have therefore focused on reactivating latent proviruses to enable immune-mediated clearance, but these have yet to succeed in reducing viral reservoirs. Here, we revisited the question of whether HIV reservoirs are predominately immunologically silent from a new angle: by querying the dynamics of HIV-specific T cell responses over long-term ART for evidence of ongoing recognition of HIV-infected cells. In longitudinal assessments, we show that the rates of change in persisting HIV Nef-specific responses, but not responses to other HIV gene products, were associated with residual frequencies of infected cells. These Nef-specific responses were highly stable over time and disproportionately exhibited a cytotoxic, effector functional profile, indicative of recent in vivo recognition of HIV antigens. These results indicate substantial visibility of the HIV-infected cells to T cells on stable ART, presenting both opportunities and challenges for the development of therapeutic approaches to curing infection.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Antígenos VIH/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , VIH-1/inmunología , Linfocitos T/inmunología , Linfocitos T/virología , Adulto , Anciano , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Estudios de Cohortes , Femenino , Granzimas/metabolismo , Infecciones por VIH/virología , Interacciones Microbiota-Huesped/efectos de los fármacos , Interacciones Microbiota-Huesped/inmunología , Humanos , Evasión Inmune , Interferón gamma/metabolismo , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Linfocitos T/efectos de los fármacos , Carga Viral , Adulto Joven
2.
Matern Child Health J ; 23(2): 155-163, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30003521

RESUMEN

Objectives To examine the effects of oral maternal vitamin B12 supplementation during pregnancy and early lactation on cognitive development in children. Method We studied 218 children born to mothers enrolled in a placebo-controlled, randomized trial of vitamin B12 supplementation during pregnancy through 6 weeks post-partum. Cognitive functions were assessed at 30 months using the Bayley Scales of Infant Development- 3rd edition (BSID III). The association of maternal sociodemographic characteristics, maternal biochemical status during pregnancy, birth weight and home environment with each sub-domain of BSID-III was examined using linear regression analysis. Separate multiple linear regression analyses for each of the BSID-III sub-domains with maternal trimester specific nutritional biomarker status was conducted. Results Children of mothers who received oral vitamin B12 supplementation had significantly higher scores on expressive language compared to children of mothers who received placebo (ß = 0.14, P = 0.03). Children of mothers with elevated serum total homocysteine (tHcy) in the second and third trimesters of pregnancy had significantly lower scores on expressive language (ß = - 0.18, P = 0.03 and ß = - 0.19, P = 0.02, respectively) and gross motor domains (ß = - 0.23, P = 0.008 and ß = - 0.30, P = 0.001, respectively) of BSID-III adjusted for treatment arm and multiple confounders, compared with children whose mothers did not have elevated tHcy. Conclusions for practice Maternal B12 supplementation during pregnancy was associated with higher expressive language scores in children at 30 months. Elevated maternal tHcy levels during pregnancy had negative associations with expressive language and gross motor domains of BSID-III. Larger trials of maternal B12 supplementation are needed to confirm these findings.


Asunto(s)
Desarrollo Infantil , Cognición/efectos de los fármacos , Suplementos Dietéticos , Desarrollo Fetal , Vitamina B 12/administración & dosificación , Niño , Cognición/fisiología , Femenino , Humanos , India/epidemiología , Lactante , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Atención Posnatal , Embarazo , Atención Prenatal , Efectos Tardíos de la Exposición Prenatal , Factores Socioeconómicos , Resultado del Tratamiento , Vitamina B 12/sangre
3.
Matern Child Nutr ; 13(2)2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27356547

RESUMEN

Maternal nutritional status during pregnancy impacts fetal brain development. Vitamin B12 plays a vital role in neuronal development. However, findings from studies on the association between maternal B12 status and child cognitive functions have been inconsistent. We performed a randomized, placebo-controlled clinical trial of oral B12 supplementation (50 µg) beginning at <14 weeks of gestation through a 6-week post-partum. In the present study, we report the effects of maternal B12 supplementation on cognitive development in infants at 9 months of age on Bayley Scales of Infant Development-III (BSID-III). One hundred eighty-three pregnant women received vitamin B12, and 183 received placebo. Nine-month BSID-III development score was available in 178 infants. There were no significant differences in maternal sociodemographic characteristics and baseline biochemical measures between infants who underwent BSID-III evaluation and infants who were not evaluated. There were no significant differences in any of the subscales of BSID-III between infants born to mothers who received B12 supplementation (n = 78) vs. placebo (n = 100). On multiple regression analysis, elevated maternal total homocysteine (tHcy) levels adjusted for treatment group, birthweight, parity, income and home environment at second trimester of pregnancy were significantly negatively associated with expressive language (ß = 3.13 points, P < 0.001), and in third trimester of pregnancy with expressive language (ß = -2.29 points, P < 0.001) and fine motor (ß = -1.41 points, P = 0.005) domains of BSID-III. While no significant effects of maternal B12 supplementation were seen on cognitive development in infants at 9 months of age, elevated maternal tHcy levels were associated with poorer cognitive performance in some of the subdomains of BSID-III. In pregnant women with elevated tHcy levels and or B12 deficiencies, it may be worthwhile to study the impact of longer term maternal supplementation on infant cognitive outcomes.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Cognición , Suplementos Dietéticos , Fenómenos Fisiologicos Nutricionales Maternos , Deficiencia de Vitamina B 12/epidemiología , Vitamina B 12/administración & dosificación , Adulto , Encéfalo/embriología , Desarrollo Infantil , Método Doble Ciego , Femenino , Desarrollo Fetal , Homocisteína/sangre , Humanos , India/epidemiología , Lactante , Modelos Lineales , Micronutrientes/administración & dosificación , Micronutrientes/sangre , Estado Nutricional , Embarazo , Efectos Tardíos de la Exposición Prenatal , Prevalencia , Factores Socioeconómicos , Resultado del Tratamiento , Adulto Joven
4.
J Nutr ; 144(5): 758-64, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24598885

RESUMEN

Pregnant women in resource-poor areas are at risk of multiple micronutrient deficiencies, and indicators of low vitamin B-12 status have been associated with adverse pregnancy outcomes, including anemia, low birth weight, and intrauterine growth retardation. To evaluate whether daily oral vitamin B-12 supplementation during pregnancy increases maternal and infant measures of vitamin B-12 status, we performed a randomized, placebo-controlled clinical trial. Pregnant women <14 wk of gestation in Bangalore, India, were randomly assigned to receive daily oral supplementation with vitamin B-12 (50 µg) or placebo through 6 wk postpartum. All women were administered iron and folic acid supplements throughout pregnancy. One hundred eighty-three women were randomly assigned to receive vitamin B-12 and 183 to receive placebo. Compared with placebo recipients, vitamin B-12-supplemented women had significantly higher plasma vitamin B-12 concentrations at both the second (median vitamin B-12 concentration: 216 vs. 111 pmol/L, P < 0.001) and third (median: 184 vs. 105 pmol/L, P < 0.001) trimesters. At 6 wk postpartum, median breast milk vitamin B-12 concentration was 136 pmol/L in vitamin B-12-supplemented women vs. 87 pmol/L in the placebo group (P < 0.0005). Among vitamin B-12-supplemented women, the incidence of delivering an infant with intrauterine growth retardation was 33 of 131 (25%) vs. 43 of 125 (34%) in those administered placebo (P = 0.11). In a subset of infants tested at 6 wk of age, median plasma vitamin B-12 concentration was 199 pmol/L in those born to supplemented women vs. 139 pmol/L in the placebo group (P = 0.01). Infant plasma methylmalonic acid and homocysteine concentrations were significantly lower in the vitamin B-12 group as well. Oral supplementation of urban Indian women with vitamin B-12 throughout pregnancy and early lactation significantly increases vitamin B-12 status of mothers and infants. It is important to determine whether there are correlations between these findings and neurologic and metabolic functions. This trial was registered at clinicaltrials.gov as NCT00641862.


Asunto(s)
Lactancia Materna , Lactancia/efectos de los fármacos , Atención Prenatal/métodos , Deficiencia de Vitamina B 12/tratamiento farmacológico , Vitamina B 12/administración & dosificación , Vitamina B 12/sangre , Adolescente , Adulto , Bangladesh/epidemiología , Suplementos Dietéticos , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Incidencia , Lactante , Recién Nacido , Lactancia/metabolismo , Masculino , Embarazo , Resultado del Embarazo/epidemiología , Factores de Riesgo , Deficiencia de Vitamina B 12/epidemiología , Vitaminas/administración & dosificación , Vitaminas/sangre , Adulto Joven
5.
J Trop Pediatr ; 60(4): 279-86, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24567309

RESUMEN

BACKGROUND: Micronutrient deficiencies and in utero exposure to HIV may impair infant neurodevelopment. OBJECTIVE: To evaluate the effect of daily multivitamin supplementation on the cognitive, language and motor development of HIV-exposed Tanzanian infants. METHODS: A total of 2387 infants were randomized to receive daily oral supplementation of multivitamins (B-complex, C and E) or placebo from age 6 weeks for 24 months. The cognitive, language and motor scales of the Bayley Scales of Infant and Toddler Development, third edition, were administered to a subset of 206 infants at age 15 months. RESULTS: Multivitamin supplementation did not improve measures of cognitive development, expressive or receptive language or gross motor capabilities. There was a trend toward improved fine motor skills among infants randomized to the multivitamin group (difference in mean score = 0.38; 95% CI = -0.01, 0.78, p = 0.06). CONCLUSION: Daily provision of multivitamins to HIV-exposed infants does not substantially improve developmental outcomes at age 15 months.


Asunto(s)
Desarrollo Infantil/efectos de los fármacos , Suplementos Dietéticos , Infecciones por VIH/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Sistema Nervioso/efectos de los fármacos , Vitaminas/administración & dosificación , Cognición , Método Doble Ciego , Femenino , Infecciones por VIH/complicaciones , Humanos , Lactante , Desarrollo del Lenguaje , Masculino , Destreza Motora , Sistema Nervioso/crecimiento & desarrollo , Embarazo , Complicaciones Infecciosas del Embarazo/virología , Resultado del Tratamiento
6.
BMJ Open ; 3(11): e003703, 2013 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-24247327

RESUMEN

OBJECTIVES: Vitamin D is an immunomodulator and can alter response to tuberculosis (TB) treatment, though randomised trials have been inconclusive to date. We present one of the first comprehensive analysis of the associations between vitamin D status and TB treatment, T-cell counts and nutritional outcomes by HIV status. DESIGN: Cohort study. SETTING: Outpatient clinics in Tanzania. PARTICIPANTS: 25-hydroxyvitamin D levels were assessed in a cohort of 677 patients with TB (344 HIV infected) initiating anti-TB treatment at enrolment in a multivitamin supplementation (excluding vitamin D) trial (Clinicaltrials.gov identifier: NCT00197704). PRIMARY AND SECONDARY OUTCOME MEASURES: Information on treatment outcomes such as failure and relapse, HIV disease progression, T-cell counts and anthropometry was collected routinely, with a median follow-up of 52 and 30 months for HIV-uninfected and HIV-infected patients, respectively. Cox and binomial regression, and generalised estimating equations were used to assess the association of vitamin D status with these outcomes. RESULTS: Mean 25-hydroxyvitamin D concentrations at enrolment were 69.8 (±21.5) nmol/L (27.9 (±8.6) ng/mL). Vitamin D insufficiency (<75 nmol/L) was associated with a 66% higher risk of relapse (95% CI 4% to 164%; 133% higher risk in HIV-uninfected patients). Each unit higher 25-hydroxyvitamin D levels at baseline were associated with a decrease of 3 (p=0.004) CD8 and 3 (p=0.01) CD3 T-cells/µL during follow-up in patients with HIV infection. Vitamin D insufficiency was also associated with a greater decrease of body mass index (BMI; -0.21 kg/m(2); 95% CI -0.39 to -0.02), during the first 8 months of follow-up. No association was observed for vitamin D status with mortality or HIV disease progression. CONCLUSIONS: Adequate vitamin D status is associated with a lower risk of relapse and with improved nutritional indicators such as BMI in patients with TB, with or without HIV infection. Further research is needed to determine the optimal dose of vitamin D and effectiveness of daily vitamin D supplementation among patients with TB.

7.
J Int AIDS Soc ; 16: 18022, 2013 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-23948440

RESUMEN

INTRODUCTION: Anaemia is prevalent among children born to HIV-positive women, and it is associated with adverse effects on cognitive and motor development, growth, and increased risks of morbidity and mortality. OBJECTIVE: To examine the effect of daily multivitamin supplementation on haematologic status and mother-to-child transmission (MTCT) of HIV through breastfeeding. METHODS: A total of 2387 infants born to HIV-positive women from Dar es Salaam, Tanzania were enrolled in a randomized, double-blind, placebo-controlled trial, and provided a daily oral supplement of multivitamins (vitamin B complex, C and E) or placebo at age 6 weeks for 24 months. Among them, 2008 infants provided blood samples and had haemoglobin concentrations measured at baseline and during a follow-up period. Anaemia was defined as haemoglobin concentrations <11 g/dL and severe anaemia <8.5 g/dL. RESULTS: Haemoglobin concentrations among children in the treatment group were significantly higher than those in the placebo group at 12 (9.77 vs. 9.64 g/dL, p=0.03), 18 (9.76 vs. 9.57 g/dL, p=0.004), and 24 months (9.93 vs. 9.75 g/dL, p=0.02) of follow-up. Compared to those in the placebo group, children in the treatment group had a 12% lower risk of anaemia (hazard ratio (HR): 0.88; 95% CI: 0.79-0.99; p=0.03). The treatment was associated with a 28% reduced risk of severe anaemia among children born to women without anaemia (HR: 0.72; 95% CI: 0.56-0.92; p=0.008), but not among those born to women with anaemia (HR: 1.10; 95% CI: 0.79-1.54; p=0.57; p for interaction=0.007). One thousand seven hundred fifty three infants who tested HIV-negative at baseline and had HIV testing during follow-up were included in the analysis for MTCT of HIV. No association was found between multivitamin supplements and MTCT of HIV. CONCLUSIONS: Multivitamin supplements improve haematologic status among children born to HIV-positive women. Further trials focusing on anaemia among HIV-exposed children are warranted in the context of antiretroviral therapy.


Asunto(s)
Anemia/tratamiento farmacológico , Dieta/métodos , Infecciones por VIH/transmisión , Transmisión Vertical de Enfermedad Infecciosa , Vitaminas/uso terapéutico , Adulto , Preescolar , Método Doble Ciego , Femenino , Hemoglobinas/análisis , Humanos , Lactante , Recién Nacido , Placebos/administración & dosificación , Embarazo , Tanzanía , Resultado del Tratamiento
8.
J Nutr ; 143(5): 722-7, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23514773

RESUMEN

Growth faltering and micronutrient deficiencies commonly coexist in HIV-exposed children in sub-Saharan Africa, and correcting deficiencies, such as those of vitamins B-complex, C, and E, may improve HIV-related endpoints and child growth. We therefore examined the effect of daily oral supplementation of vitamins B-complex, C, and E on growth among 2341 children born to HIV-infected mothers in Tanzania. HIV-infected women pregnant at ≤32 wk of gestation were enrolled in the study. Children were randomized at age 6 wk to receive multivitamins or placebo until age 104 wk. All women received the same types of vitamins pre- and postnatally. At 6 wk, 256 children (11.1%) were HIV infected and the mean (SD) Z-scores for length for age (LAZ), weight for length (WLZ), and weight for age (WAZ) were -0.39 ± 1.20, -0.21 ± 1.23, and -0.52 ± 1.11, respectively. There was no overall treatment effect on LAZ, WLZ, or WAZ profiles during the follow-up (P ≥ 0.15). There was no treatment effect from 6 to 104 wk on LAZ [(95% CI: -0.14, 0.13); P = 0.94], WLZ [(95% CI: -0.17, 0.13); P = 0.78], or WAZ [(95% CI: -0.15, 0.16); P = 0.97] or on the incidence of growth failure, defined as respective Z-scores < -2 (P ≥ 0.29). Among the subgroup of HIV-uninfected children, there was no treatment effect from 6 to 104 wk on LAZ, WLZ, and WAZ (P ≥ 0.71) or on the incidence of growth failure (P ≥ 0.16). Multivitamin supplements had no effect on growth among children born to HIV-infected women who were themselves receiving multivitamins.


Asunto(s)
Suplementos Dietéticos , Trastornos del Crecimiento/prevención & control , Crecimiento/efectos de los fármacos , Infecciones por VIH/complicaciones , Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Infecciosas del Embarazo , Vitaminas/farmacología , Adulto , Avitaminosis/complicaciones , Avitaminosis/tratamiento farmacológico , Estatura/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Femenino , Trastornos del Crecimiento/complicaciones , Trastornos del Crecimiento/epidemiología , Humanos , Incidencia , Lactante , Masculino , Madres , Embarazo , Tanzanía/epidemiología , Vitaminas/uso terapéutico , Adulto Joven
9.
Am J Clin Nutr ; 96(6): 1437-46, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23134887

RESUMEN

BACKGROUND: Multiple micronutrients (vitamin B complex and vitamins C and E) were effective at reducing infectious disease morbidity, HIV disease progression, and poor pregnancy outcomes in HIV-infected women. OBJECTIVE: The objective was to evaluate whether direct supplementation of these micronutrients to HIV-exposed infants reduces mortality and morbidity. DESIGN: Infants born to HIV-infected women from Dar es Salaam, Tanzania, were randomly assigned to receive daily oral supplementation of multiple multivitamins (vitamin B complex and vitamins C and E) or placebo from age 6 wk for 24 mo. All-cause mortality, hospitalizations, and unscheduled clinic visits were recorded. Morbidities were recorded during monthly follow-up visits. All mothers received multiple micronutrients throughout the study. RESULTS: A total of 1193 infants were randomly assigned to receive micronutrients and 1194 to receive placebo. There were 138 child deaths in the multivitamin group and 124 deaths in the placebo group (HR: 1.13; 95% CI: 0.88, 1.44; P = 0.33). Hospitalizations (RR: 0.83; 95% CI: 0.62, 1.13; P = 0.23), unscheduled clinic visits (RR: 0.97; 95% CI: 0.85, 1.10; P = 0.59), and maternal reports of diarrhea (RR: 0.97; 0.87, 1.10; P = 0.64) were not significantly different between the 2 groups. Fever (P = 0.02) and vomiting (P = 0.007) were significantly lower in the multivitamin group. Among 429 children whose mothers received antiretroviral (ARV) therapy, multivitamin use had no effect on mortality but was associated with a significant reduction in hospitalizations (P = 0.035), episodes of fever (P = 0.005), and episodes of fever and cough (P = 0.019). CONCLUSIONS: In the setting of maternal micronutrient supplementation, supplementation of HIV-exposed infants with vitamin B and vitamins C and E does not reduce mortality. Studies of nutrition supplementation in ARV-exposed infants may be warranted.


Asunto(s)
Suplementos Dietéticos , Seropositividad para VIH/transmisión , Fenómenos Fisiológicos Nutricionales del Lactante , Control de Infecciones/métodos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Fenómenos Fisiologicos Nutricionales Maternos , Micronutrientes/uso terapéutico , Antirretrovirales/efectos adversos , Antirretrovirales/uso terapéutico , Lactancia Materna/efectos adversos , Método Doble Ciego , Femenino , Fiebre/prevención & control , Seropositividad para VIH/tratamiento farmacológico , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Masculino , Micronutrientes/administración & dosificación , Áreas de Pobreza , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Tanzanía , Vómitos/prevención & control
10.
PLoS One ; 7(5): e37350, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22606361

RESUMEN

BACKGROUND: Experimental data suggest a role for iron in the course of tuberculosis (TB) infection, but there is limited evidence on the potential effects of iron deficiency or iron overload on the progression of TB disease in humans. The aim of the present analysis was to examine the association of iron status with the risk of TB progression and death. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed plasma samples and data collected as part a randomized micronutrient supplementation trial (not including iron) among HIV-infected and HIV-uninfected TB patients in Dar es Salaam, Tanzania. We prospectively related baseline plasma ferritin concentrations from 705 subjects (362 HIV-infected and 343 HIV-uninfected) to the risk of treatment failure at one month after initiation, TB recurrence and death using binomial and Cox regression analyses. Overall, low (plasma ferritin<30 µg/L) and high (plasma ferritin>150 µg/L for women and>200 µg/L for men) iron status were seen in 9% and 48% of patients, respectively. Compared with normal levels, low plasma ferritin predicted an independent increased risk of treatment failure overall (adjusted RR = 1.95, 95% CI: 1.07 to 3.52) and of TB recurrence among HIV-infected patients (adjusted RR = 4.21, 95% CI: 1.22 to 14.55). High plasma ferritin, independent of C-reactive protein concentrations, was associated with an increased risk of overall mortality (adjusted RR = 3.02, 95% CI: 1.95 to 4.67). CONCLUSIONS/SIGNIFICANCE: Both iron deficiency and overload exist in TB patients and may contribute to disease progression and poor clinical outcomes. Strategies to maintain normal iron status in TB patients could be helpful to reduce TB morbidity and mortality.


Asunto(s)
Hierro/metabolismo , Tuberculosis Pulmonar/metabolismo , Adulto , Estudios de Cohortes , Femenino , Ferritinas/sangre , Infecciones por VIH/complicaciones , Humanos , Deficiencias de Hierro , Sobrecarga de Hierro/complicaciones , Sobrecarga de Hierro/metabolismo , Masculino , Micronutrientes/administración & dosificación , Estudios Prospectivos , Tanzanía/epidemiología , Insuficiencia del Tratamiento , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/mortalidad , Tuberculosis Pulmonar/terapia , Adulto Joven
11.
J Nutr ; 142(2): 350-7, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22190024

RESUMEN

Many studies have documented a high prevalence of anemia among tuberculosis (TB) patients and anemia at TB diagnosis has been associated with an increased risk of death. However, little is known about the factors contributing to the development of TB-associated anemia and their importance in TB disease progression. Data from a randomized clinical trial of micronutrient supplementation in patients with pulmonary TB in Tanzania were analyzed. Repeated measures of anemia with iron deficiency, anemia without iron deficiency, and iron deficiency without anemia were assessed as risk factors for treatment failure, TB recurrence, and mortality. The prevalence of anemia (hemoglobin < 110 g/L) at baseline was 64%, more than one-half of which was related to iron deficiency (mean corpuscular volume , 80 fL). We found no evidence of an association between anemia (with or without iron deficiency) or iron deficiency without anemia at baseline and the risk of treatment failure at 1 mo after initiation. Anemia without iron deficiency was associated with an independent, 4-fold increased risk of TB recurrence [adjusted RR = 4.10 (95% CI = 1.88, 8.91); P < 0.001]. Iron deficiency and anemia (with and without iron deficiency) were associated with a 2- to nearly 3-fold independent increase in the risk of death [adjusted RR for iron deficiency without anemia = 2.89 (95% CI = 1.53, 5.47); P = 0.001; anemia without iron deficiency = 2.72 (95% CI = 1.50, 4.93); P = 0.001; iron deficiency anemia = 2.13 (95% CI = 1.10, 4.11); P = 0.02]. Efforts to identify and address the conditions contributing to TB-associated anemia, including iron deficiency, could play an important role in reducing morbidity and mortality in areas heavily affected by TB.


Asunto(s)
Anemia Ferropénica/complicaciones , Tuberculosis/complicaciones , Tuberculosis/mortalidad , Adulto , Anemia Ferropénica/epidemiología , Suplementos Dietéticos , Femenino , Infecciones por VIH/complicaciones , Humanos , Masculino , Oportunidad Relativa , Estudios Prospectivos , Factores de Riesgo , Tanzanía/epidemiología , Tuberculosis/epidemiología , Adulto Joven
12.
Nutr J ; 10: 120, 2011 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-22039966

RESUMEN

BACKGROUND: Children with tuberculosis often have underlying nutritional deficiencies. Multivitamin supplementation has been proposed as a means to enhance the health of these children; however, the efficacy of such an intervention has not been examined adequately. METHODS: 255 children, aged six weeks to five years, with tuberculosis were randomized to receive either a daily multivitamin supplement or a placebo in the first eight weeks of anti-tuberculous therapy in Tanzania. This was only 64% of the proposed sample size as the trial had to be terminated prematurely due to funding constraints. They were followed up for the duration of supplementation through clinic and home visits to assess anthropometric indices and laboratory parameters, including hemoglobin and albumin. RESULTS: There was no significant effect of multivitamin supplementation on the primary endpoint of the trial: weight gain after eight weeks. However, significant differences in weight gain were observed among children aged six weeks to six months in subgroup analyses (n=22; 1.08 kg, compared to 0.46 kg in the placebo group; 95% CI=0.12, 1.10; p=0.01). Supplementation resulted in significant improvement in hemoglobin levels at the end of follow-up in children of all age groups; the median increase in children receiving multivitamins was 1.0 g/dL, compared to 0.4 g/dL in children receiving placebo (p<0.01). HIV-infected children between six months and three years of age had a significantly higher gain in height if they received multivitamins (n=48; 2 cm, compared to 1 cm in the placebo group; 95% CI=0.20, 1.70; p=0.01; p for interaction by age group=0.01). CONCLUSIONS: Multivitamin supplementation for a short duration of eight weeks improved the hematological profile of children with tuberculosis, though it didn't have any effect on weight gain, the primary outcome of the trial. Larger studies with a longer period of supplementation are needed to confirm these findings and assess the effect of multivitamins on clinical outcomes including treatment success and growth failure. CLINICALTRIALS.GOV IDENTIFIER: NCT00145184.


Asunto(s)
Suplementos Dietéticos , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Vitaminas/administración & dosificación , Antropometría , Preescolar , Método Doble Ciego , Determinación de Punto Final , Femenino , Estudios de Seguimiento , Infecciones por VIH/complicaciones , Humanos , Lactante , Masculino , Tanzanía/epidemiología , Resultado del Tratamiento , Tuberculosis/complicaciones , Aumento de Peso/efectos de los fármacos
13.
Am J Clin Nutr ; 92(4): 881-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20739426

RESUMEN

BACKGROUND: Supplementation in lactating HIV-1-infected women with preformed vitamin A and ß-carotene (VA/BC) increases the risk of mother-to-child transmission of HIV through breastfeeding. Identifying a biological mechanism to explain this unexpected finding would lend support to a causal effect. OBJECTIVE: The aim of the study was to evaluate the effect of VA/BC or multivitamin (B complex, vitamin C, and vitamin E) supplementation of HIV-infected women on HIV shedding in breast milk during the first 2 y postpartum. DESIGN: We quantified viral (cell-free) and proviral (cell-associated) HIV loads in breast-milk samples collected ≤15 d after delivery and every 3 mo thereafter from 594 Tanzanian HIV-1-infected women who participated in a randomized trial. Women received 1 of the following 4 daily oral regimens in a 2 × 2 factorial fashion during pregnancy and throughout the first 2 y postpartum: multivitamin, VA/BC, multivitamin including VA/BC, or placebo. RESULTS: The proportion of breast-milk samples with detectable viral load was significantly higher in women who received VA/BC (51.3%) than in women who were not assigned to VA/BC (44.8%; P = 0.02). The effect was apparent ≥6 mo postpartum (relative risk: 1.34; 95% CI: 1.04, 1.73). No associations with proviral load were observed. The multivitamin had no effects. In observational analyses, ß-carotene but not retinol breast-milk concentrations were significantly associated with an increased viral load in milk. CONCLUSIONS: VA/BC supplementation in lactating women increases the HIV load in breast milk. This finding contributes to explaining the adverse effect of VA/BC on mother-to-child transmission. ß-Carotene appears to have an effect on breast-milk viral load, independent of preformed vitamin A. This trial was registered at clinicaltrials.gov as NCT00197756.


Asunto(s)
Suplementos Dietéticos , VIH/aislamiento & purificación , Leche Humana/virología , Esparcimiento de Virus/efectos de los fármacos , Vitamina A/farmacología , Vitaminas/farmacología , beta Caroteno/farmacología , Lactancia Materna/efectos adversos , Femenino , VIH/efectos de los fármacos , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Humanos , Embarazo , Factores de Riesgo , Tanzanía , Carga Viral , Vitamina A/efectos adversos , beta Caroteno/efectos adversos
14.
Br J Nutr ; 103(12): 1784-91, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20211040

RESUMEN

We examined whether there are sex differences in the effect of vitamin supplements on birth outcomes, mortality and morbidity by 2 years of age among children born to HIV-infected women in Tanzania. A randomised placebo-controlled trial was conducted among 959 mother-infant pairs. HIV-infected pregnant women were randomly assigned to receive a daily oral dose of one of four regimens: multivitamins (vitamins B-complex, C and E), vitamin A plus beta-carotene, multivitamins including vitamin A plus beta-carotene or placebo. Supplements were administered during pregnancy and continued after delivery. The beneficial effect of multivitamins on decreasing the risk of low birth weight was stronger among girls (relative risks (RR) = 0.39, 95 % CI 0.22, 0.67) than among boys (RR = 0.81, 95 % CI 0.44, 1.49; P for interaction = 0.08). Maternal multivitamin supplements resulted in 32 % reduction in mortality among girls (RR = 0.68, 95 % CI 0.47, 0.97), whereas no effect was found among boys (RR = 1.20, 95 % CI 0.80, 1.78; P for interaction = 0.04). Multivitamins had beneficial effects on the overall risks of diarrhoea that did not differ by sex. Vitamin A plus beta-carotene alone increased the risk of HIV transmission, but had no effects on mortality, and we found no sex differences in these effects. Sex differential effects of multivitamins on mortality may be due to sex-related differences in the immunological or genetic factors. More research is warranted to examine the effect of vitamins by sex and better understand biological mechanisms mediating such effects.


Asunto(s)
Suplementos Dietéticos , Infecciones por VIH , Mortalidad Infantil , Transmisión Vertical de Enfermedad Infecciosa , Fenómenos Fisiologicos Nutricionales Maternos , Complicaciones Infecciosas del Embarazo , Vitaminas/uso terapéutico , Adulto , Diarrea/etiología , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/transmisión , VIH-1 , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Masculino , Embarazo , Factores de Riesgo , Factores Sexuales , Tanzanía/epidemiología , Vitaminas/farmacología , Adulto Joven
15.
J Trop Pediatr ; 56(1): 27-35, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19502599

RESUMEN

Vitamin A supplementation starting at 6 months of age is an important child survival intervention; however, not much is known about the association between vitamin A status before 6 months and mortality among children born to HIV-infected women. Plasma concentrations of vitamins A and B-12 were available at 6 weeks of age (n = 576 and 529, respectively) for children born to HIV-infected women and they were followed up for morbidity and survival status until 24 months after birth. Children in the highest quartile of vitamin A had a 49% lower risk of death by 24 months of age compared to the lowest quartile (HR: 0.51, 95% CI: 0.29-0.90; P-value for trend = 0.01). Higher vitamin A levels were protective in the sub-groups of HIV-infected and un-infected children but this was statistically significant only in the HIV-uninfected subgroup. Higher vitamin A concentrations in plasma are protective against mortality in children born to HIV-infected women.


Asunto(s)
Infecciones por VIH/mortalidad , Vitamina A/sangre , Vitamina B 12/sangre , Complejo Vitamínico B/sangre , Vitaminas/sangre , Preescolar , Suplementos Dietéticos/efectos adversos , Método Doble Ciego , Femenino , Estudios de Seguimiento , Infecciones por VIH/complicaciones , Infecciones por VIH/transmisión , VIH-1 , Humanos , Lactante , Mortalidad Infantil , Transmisión Vertical de Enfermedad Infecciosa , Masculino , Morbilidad , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Análisis de Supervivencia , Tanzanía/epidemiología , Vitamina A/administración & dosificación , Vitamina B 12/administración & dosificación , Complejo Vitamínico B/administración & dosificación , Vitaminas/administración & dosificación
16.
Public Health Nutr ; 13(2): 289-96, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19650963

RESUMEN

OBJECTIVE: Predictors and consequences of childhood anaemia in settings with high HIV prevalence are not well known. The aims of the present study were to identify maternal and child predictors of anaemia among children born to HIV-infected women and to study the association between childhood anaemia and mortality. DESIGN: Prospective cohort study. Maternal characteristics during pregnancy and Hb measurements at 3-month intervals from birth were available for children. Information was also collected on malaria and HIV infection in the children, who were followed up for survival status until 24 months after birth. SETTING: Dar es Salaam, Tanzania. SUBJECTS: The study sample consisted of 829 children born to HIV-positive women. RESULTS: Advanced maternal clinical HIV disease (relative risk (RR) for stage > or =2 v. stage 1: 1.31, 95 % CI 1.14, 1.51) and low CD4 cell counts during pregnancy (RR for <350 cells/mm3 v. > or =350 cells/mm3: 1.58, 95 % CI 1.05, 2.37) were associated with increased risk of anaemia among children. Birth weight <2500 g, preterm birth (<34 weeks), malaria parasitaemia and HIV infection in the children also increased the risk of anaemia. Fe-deficiency anaemia in children was an independent predictor of mortality in the first two years of life (hazard ratio 1.99, 95 % CI 1.06, 3.72). CONCLUSIONS: Comprehensive care including highly active antiretroviral therapy to eligible HIV-infected women during pregnancy could reduce the burden of anaemia in children. Programmes for the prevention of mother-to-child transmission of HIV and antimalarial treatment to children could improve child survival in settings with high HIV prevalence.


Asunto(s)
Anemia Ferropénica/epidemiología , Anemia/epidemiología , Infecciones por VIH/complicaciones , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo , Adulto , Anemia/mortalidad , Anemia/prevención & control , Anemia Ferropénica/mortalidad , Anemia Ferropénica/prevención & control , Antirretrovirales/uso terapéutico , Antimaláricos/uso terapéutico , Terapia Antirretroviral Altamente Activa , Peso al Nacer/fisiología , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , Edad Gestacional , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Infecciones por VIH/transmisión , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Malaria/complicaciones , Malaria/tratamiento farmacológico , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Tanzanía
17.
J Infect Dis ; 197(11): 1499-505, 2008 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-18471061

RESUMEN

BACKGROUND: Tuberculosis (TB) often coincides with nutritional deficiencies. The effects of micronutrient supplementation on TB treatment outcomes, clinical complications, and mortality are uncertain. METHODS: We conducted a randomized, double-blind, placebo-controlled trial of micronutrients (vitamins A, B complex, C, and E, as well as selenium) in Dar es Salaam, Tanzania. We enrolled 471 human immunodeficiency virus (HIV)-infected and 416 HIV-negative adults with pulmonary TB at the time of initiating chemotherapy and monitored them for a median of 43 months. RESULTS: Micronutrients decreased the risk ofTB recurrence by 45% overall (95% confidence interval [CI], 7% to 67%; P = .02) and by 63% in HIV-infected patients (95% CI, 8% to 85%; P = .02). There were no significant effects on mortality overall; however, we noted a marginally significant 64% reduction of deaths in HIV-negative subjects (95% CI, -14% to 88%; P = .08). Supplementation increased CD3+ and CD4+ cell counts and decreased the incidence of extrapulmonary TB and genital ulcers in HIV-negative patients. Micronutrients reduced the incidence of peripheral neuropathy by 57% (95% CI, 41% to 69%; P < .001), irrespective of HIV status. There were no significant effects on weight gain, body composition, anemia, or HIV load. CONCLUSIONS: Micronutrient supplementation could improve the outcome in patients undergoing TB chemotherapy in Tanzania.


Asunto(s)
Micronutrientes/uso terapéutico , Subgrupos de Linfocitos T/inmunología , Tuberculosis Pulmonar/prevención & control , Tuberculosis Pulmonar/terapia , Adulto , Método Doble Ciego , Femenino , Infecciones por VIH/complicaciones , Humanos , Incidencia , Masculino , Prevención Secundaria , Tanzanía , Resultado del Tratamiento , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/mortalidad
18.
Am J Clin Nutr ; 81(4): 880-8, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15817867

RESUMEN

BACKGROUND: Linear growth retardation and wasting are common in children born to HIV-infected women. Inexpensive interventions that could improve the postnatal growth pattern of such children are needed. OBJECTIVE: The objective was to examine the effect of supplementing HIV-infected women with multivitamins or vitamin A and beta-carotene, during and after pregnancy, on the growth of their children during the first 2 y of life. DESIGN: We conducted a randomized placebo-controlled trial in 886 mother-infant pairs in Tanzania. At the first prenatal visit, HIV-infected women were randomly assigned to 1 of 4 daily oral regimens in a 2 x 2 factorial fashion: multivitamins (MV: thiamine, riboflavin, vitamin B-6, niacin, vitamin B-12, vitamin C, vitamin E, and folic acid), preformed vitamin A + beta-carotene (VA/BC), MV including VA/BC, or placebo. Supplementation continued during the first 2 y postpartum and thereafter. Children were weighed and measured monthly, and all received vitamin A supplements after 6 mo of age per the standard of care. RESULTS: Multivitamins had a significant positive effect on attained weight (459 g; 95% CI: 35, 882; P = 0.03) and on weight-for-age (0.42; 95% CI: 0.07, 0.77; P = 0.02) and weight-for-length (0.38; 95% CI: 0.07, 0.68; P = 0.01) z scores at 24 mo. VA/BC seemed to reduce the benefits of MV on these outcomes. No significant effects were observed on length, midupper arm circumference, or head circumference. CONCLUSION: Supplementation of HIV-infected women with multivitamins (vitamin B complex, vitamin C, and vitamin E) during pregnancy and lactation is an effective intervention for improving ponderal growth in children.


Asunto(s)
Desarrollo Infantil/efectos de los fármacos , Infecciones por VIH/transmisión , Atención Prenatal , Vitaminas/farmacología , Adulto , Antioxidantes/farmacología , Femenino , Infecciones por VIH/epidemiología , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Embarazo , Tanzanía/epidemiología , Vitamina A/farmacología , beta Caroteno/farmacología
19.
AIDS ; 17(6): 821-30, 2003 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-12660529

RESUMEN

OBJECTIVE: To evaluate phenotypic drug susceptibility and non-nucleoside reverse transcriptase inhibitor hypersusceptibility as predictors of the time to virological failure. DESIGN: In a randomized clinical trial, phenotypic susceptibility was retrospectively determined among 131 exclusively nucleoside reverse transcriptase inhibitor (NRTI)-experienced patients with baseline HIV-RNA levels greater than 2000 copies/ml. Subjects were assigned two NRTI drugs and were randomly assigned to nelfinavir, efavirenz, or both. Virological failure was defined as two HIV-RNA measurements of 2000 copies/ml or greater at or after week 16 and before treatment discontinuation. METHODS: Using biological cut-offs to define resistance, assigned NRTI and randomized drug regimens, continuous and dichotomous phenotypic susceptibility scores (PSS) were calculated for each virus. Efavirenz hypersusceptibility as a dichotomous value was defined as less than 0.4-fold resistance. Associations between virological failure and continuous and dichotomous PSS were evaluated using Kaplan-Meier curves and Cox proportional hazards regression models. RESULTS: A higher baseline viral load (P < 0.02) and lower dichotomous or continuous baseline PSS (P = 0.004 and P < 0.001, respectively) were independently associated with virological failure. In the 85 subjects who received efavirenz, efavirenz hypersusceptibility (P = 0.042, hazard ratio 0.43, 95% confidence interval 0.19-0.97) was independently associated with a reduced risk of virological failure. CONCLUSION: Reduced phenotypic susceptibility was a significant independent risk factor for virological failure. The presence of efavirenz hypersusceptibility appeared to enhance virological responses during treatment with efavirenz in combination with NRTIs. The retrospective calculation of continuous PSS accurately identified treatment regimens containing sufficient drug activity to prevent virological failure.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Alquinos , Benzoxazinas , Ciclopropanos , Farmacorresistencia Viral , Quimioterapia Combinada , Femenino , Infecciones por VIH/virología , Transcriptasa Inversa del VIH/antagonistas & inhibidores , VIH-1/aislamiento & purificación , VIH-1/fisiología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Oxazinas/uso terapéutico , Fenotipo , Modelos de Riesgos Proporcionales , ARN Viral/sangre , Estudios Retrospectivos , Factores de Riesgo , Insuficiencia del Tratamiento , Carga Viral , Replicación Viral/efectos de los fármacos
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