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1.
BMC Infect Dis ; 7: 63, 2007 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-17594484

RESUMEN

BACKGROUND: Low vitamin E levels are often found in HIV-1 infection, and studies have suggested that higher levels may decrease the risk of disease progression. However, vitamin E supplementation has also been reported to increase CCR5 expression, which could increase HIV-1 replication. We hypothesized that vitamin E levels at HIV-1 acquisition may influence disease progression. METHODS: Vitamin E status was measured in stored samples from the last pre-infection visit for 67 Kenyan women with reliably estimated dates of HIV-1 acquisition. Regression analyses were used to estimate associations between pre-infection vitamin E and plasma viral load, time to CD4 count <200 cells/muL, and mortality. RESULTS: After controlling for potential confounding factors, each 1 mg/L increase in pre-infection vitamin E was associated with 0.08 log10 copies/mL (95% CI -0.01 to +0.17) higher set point viral load and 1.58-fold higher risk of mortality (95% CI 1.15-2.16). The association between higher pre-infection vitamin E and mortality persisted after adjustment for set point viral load (HR 1.55, 95% CI 1.13-2.13). CONCLUSION: Higher pre-infection vitamin E levels were associated with increased mortality. Further research is needed to elucidate the role vitamin E plays in HIV-1 pathogenesis.


Asunto(s)
Infecciones por VIH/sangre , Infecciones por VIH/mortalidad , VIH-1/patogenicidad , Carga Viral , Vitamina E/sangre , Adulto , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/metabolismo , Humanos , Kenia/epidemiología , Estudios Prospectivos , Análisis de Supervivencia , Deficiencia de Vitamina E/virología
2.
Int J STD AIDS ; 18(3): 202-6, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17362556

RESUMEN

Observational studies have suggested that low serum beta-carotene concentrations may influence HIV-1 disease progression. However, randomized trials have not demonstrated beneficial effects of beta-carotene supplementation. To understand this discrepancy, we conducted a cross-sectional study among 400 HIV-1-seropositive women in Mombasa, Kenya, to correlate serum beta-carotene concentrations with several measures of HIV-1 disease severity. beta-Carotene concentrations were significantly associated with biologic markers of HIV-1 disease progression (CD4 count, HIV-1 plasma viral load, serum C-reactive protein [CRP] concentration, and serum albumin level). In multivariate analysis, beta-carotene concentrations below the median were associated with elevated CRP (>10 mg/l, adjusted odds ratio [aOR] 3.32, 95% confidence interval [CI] 1.99-5.53, P<0.001) and higher HIV-1 plasma viral load (for each log(10) copies/mL increase, aOR 1.38, 95% CI 1.01-1.88, P=0.04). In the context of negative findings from randomized trials of beta-carotene supplementation in HIV-1-seropositive individuals, these results suggest that low beta-carotene concentrations primarily reflect more active HIV-1 infection rather than a deficiency amenable to intervention.


Asunto(s)
Infecciones por VIH/sangre , VIH-1/crecimiento & desarrollo , beta Caroteno/sangre , Adulto , Proteína C-Reactiva/metabolismo , Recuento de Linfocito CD4 , Estudios Transversales , Progresión de la Enfermedad , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Kenia , Carga Viral , Vitamina A/administración & dosificación , beta Caroteno/deficiencia
3.
BMC Infect Dis ; 6: 85, 2006 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-16712720

RESUMEN

BACKGROUND: Low serum selenium has been associated with lower CD4 counts and greater mortality among HIV-1-seropositive individuals, but most studies have not controlled for serum albumin and the presence of an acute phase response. METHODS: A cross-sectional study was conducted to evaluate relationships between serum selenium concentrations and CD4 count, plasma viral load, serum albumin, and acute phase response markers among 400 HIV-1-seropositive women. RESULTS: In univariate analyses, lower CD4 count, higher plasma viral load, lower albumin, and the presence of an acute phase response were each significantly associated with lower serum selenium concentrations. In multivariate analyses including all four of these covariates, only albumin remained significantly associated with serum selenium. For each 0.1 g/dl increase in serum albumin, serum selenium increased by 0.8 microg/l (p < 0.001). Women with an acute phase response also had lower serum selenium (by 5.6 microg/l, p = 0.06). CONCLUSION: Serum selenium was independently associated with serum albumin, but not with CD4 count or plasma viral load, in HIV-1-seropositive women. Our findings suggest that associations between lower serum selenium, lower CD4 count, and higher plasma viral load may be related to the frequent occurrence of low serum albumin and the acute phase response among individuals with more advanced HIV-1 infection.


Asunto(s)
Reacción de Fase Aguda/sangre , Infecciones por VIH/sangre , Infecciones por VIH/patología , Selenio/sangre , Albúmina Sérica/metabolismo , Adulto , Peso Corporal , Recuento de Linfocito CD4 , Estudios Transversales , Femenino , Humanos , ARN Viral/sangre
4.
J Nutr ; 136(6): 1624-9, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16702331

RESUMEN

The ratio of retinol-binding protein (RBP) to transthyretin (TTR) has been proposed as an indirect method with which to assess vitamin A status in the context of inflammation. Few studies have been conducted among adults, and none examined the effect of HIV-1 infection. Our goal was to assess the RBP:TTR ratio among adults, including the effects of HIV-1 and the acute phase response. We used data from a cross-sectional study of 600 Kenyan women, of whom 400 had HIV-1. The effect of vitamin A supplementation among the HIV-1-infected participants was subsequently assessed in a randomized trial. Among HIV-1-uninfected women without an acute phase response, a RBP:TTR cut-off value of 0.25 had approximately 80% sensitivity and specificity to detect vitamin A deficiency (retinol <0.70 micromol/L). No RBP:TTR cut-off value demonstrated both high sensitivity and specificity among HIV-1 infected women without evidence of inflammation. HIV-1 infection and advanced HIV-1 disease were associated with higher RBP:TTR ratios. The effect of HIV-1 was independent of the acute phase response, which also increased the RBP:TTR ratio. Serum retinol increased with vitamin A supplementation among those with a low RBP:TTR ratio, although the effect was small and was not present among those with concurrent inflammation. Thus, the RBP:TTR ratio has modest ability to predict vitamin A deficiency among healthy adults, but HIV-1 infection alters the ratio, even in the absence of the acute phase response. Our results raise questions about the utility of this measurement given the high prevalence of HIV-1 infection in areas where vitamin A deficiency is common.


Asunto(s)
Reacción de Fase Aguda/metabolismo , Infecciones por VIH/metabolismo , VIH-1 , Prealbúmina/metabolismo , Proteínas de Unión al Retinol/metabolismo , Adulto , Femenino , Humanos , Deficiencia de Vitamina A/metabolismo
5.
J Acquir Immune Defic Syndr ; 37(5): 1657-63, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15577425

RESUMEN

To test the hypothesis that micronutrient supplementation decreases genital HIV-1 shedding, a double-blind, randomized, placebo-controlled trial of 6 weeks of multivitamin plus selenium supplementation vs. placebo was conducted among 400 HIV-1-seropositive, nonpregnant, antiretroviral-naive women in Mombasa, Kenya. Primary outcome measures included cervical and vaginal shedding of HIV-1-infected cells and RNA. Secondary outcomes included plasma viral load and CD4 count. Surprisingly, the odds of detection of vaginal HIV-1-infected cells were 2.5-fold higher (P = 0.001) and the quantity of HIV-1 RNA in vaginal secretions was 0.37 log10 copies/swab higher (P = 0.004) among women who received micronutrients in comparison to placebo, even after adjustment for potential confounders including baseline HIV-1 shedding and CD4 count. The increase in vaginal HIV-1 shedding was greatest among women who had normal baseline selenium levels. Micronutrient supplementation resulted in higher CD4 (+23 cells/microL, P = 0.03) and CD8 (+74 cells/microL, P = 0.005) counts compared with placebo but did not alter the plasma viral load. In this randomized trial, micronutrients resulted in higher levels of genital HIV-1 shedding compared with placebo. The potential benefit of micronutrient supplementation in HIV-1-seropositive women should be considered in relation to the potential for increased infectivity.


Asunto(s)
Cuello del Útero/virología , VIH-1/efectos de los fármacos , Micronutrientes/administración & dosificación , Selenio/administración & dosificación , Vagina/virología , Esparcimiento de Virus/efectos de los fármacos , Vitaminas/administración & dosificación , Adolescente , Adulto , Suplementos Dietéticos , Método Doble Ciego , Femenino , Infecciones por VIH/virología , Humanos , Persona de Mediana Edad , ARN Viral/análisis
6.
J Infect Dis ; 189(8): 1466-71, 2004 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15073684

RESUMEN

Cross-sectional analyses have associated vitamin A deficiency with genital shedding of herpes simplex virus (HSV) among human immunodeficiency virus type 1 (HIV-1)-infected women. A randomized clinical trial of vitamin A supplementation given daily for 6 weeks was conducted among 376 women in Mombasa, Kenya, who were coinfected with HSV-2 and HIV-1. At follow-up, there was no significant difference in the detection of genital HSV DNA between women receiving vitamin A supplementation and women receiving placebo (40% vs. 44%, respectively; P = .5) Among women shedding HSV, there was no significant difference in the mean HSV DNA quantity between the group that received vitamin A supplementation and the group that received placebo (4.51 vs. 4.67 log10 copies/swab; P = .6). HSV shedding was associated with significantly higher vaginal and cervical HIV-1 shedding, even after controlling for the plasma HIV-1 load and the CD4 count. Vitamin A supplementation is unlikely to decrease HSV shedding and infectivity.


Asunto(s)
Infecciones por VIH/virología , VIH-1/fisiología , Herpes Genital/virología , Herpesvirus Humano 2/fisiología , Vitamina A/administración & dosificación , Adulto , Recuento de Linfocito CD4 , ADN Viral/química , ADN Viral/genética , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Femenino , Infecciones por VIH/tratamiento farmacológico , Herpes Genital/inmunología , Humanos , Reacción en Cadena de la Polimerasa , Esparcimiento de Virus/efectos de los fármacos
7.
J Acquir Immune Defic Syndr ; 31(2): 243-9, 2002 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-12394804

RESUMEN

Among HIV-1-infected individuals, vitamin A deficiency has been associated with faster disease progression and greater infectivity in observational studies, but randomized clinical trials have shown no effect of vitamin A supplementation. We conducted a cross-sectional study of 400 HIV-1-infected and 200 HIV-1-uninfected women in Mombasa, Kenya to examine the relations between vitamin A deficiency (serum retinol <30 microg/dL) and HIV-1 status, HIV-1 disease stage, and the acute phase response (serum C-reactive protein >or=10 mg/L and/or alpha1-acid glycoprotein >or=1.2 g/L). Among the HIV-1-infected women, the effect of vitamin A supplementation was examined in a randomized trial. Vitamin A deficiency was independently associated with HIV-1 infection (OR = 2.7, 95% CI: 1.9-4.0) and the acute phase response (OR = 2.8, 95% CI: 1.9-4.1). Among HIV-1-infected women, vitamin A deficiency and the acute phase response were associated with each other and were both independently associated with higher HIV-1 plasma viral load and lower CD4 count. HIV-1-infected women having an acute phase response had no increase in serum vitamin A levels after supplementation. Serum levels increased significantly among women without an acute phase response, although not to normal levels among women who were deficient at baseline. Among HIV-1-infected individuals, it is likely that low serum vitamin A concentrations reflect more active infection and the acute phase response. These results provide possible explanations for the disparity between observational studies and randomized trials of vitamin A for HIV-1 infection.


Asunto(s)
Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Deficiencia de Vitamina A/complicaciones , Deficiencia de Vitamina A/tratamiento farmacológico , Vitamina A/uso terapéutico , Adolescente , Adulto , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Recuento de Linfocito CD4 , Estudios Transversales , Femenino , Infecciones por VIH/sangre , Humanos , Kenia , Persona de Mediana Edad , Oportunidad Relativa , Orosomucoide/análisis , Carga Viral , Vitamina A/sangre
8.
J Infect Dis ; 185(8): 1187-91, 2002 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-11930332

RESUMEN

Observational studies have associated vitamin A deficiency with vaginal shedding of human immunodeficiency virus (HIV) type 1-infected cells and mother-to-child HIV-1 transmission. To assess the effect of vitamin A supplementation on vaginal shedding of HIV-1, a randomized, double-blind, placebo-controlled trial of 6 weeks of daily oral vitamin A (10,000 IU of retinyl palmitate) was conducted among 400 HIV-1-infected women in Mombasa, Kenya. At follow-up, there was no statistically significant difference in the prevalence of HIV-1 DNA (18% vs. 21%, P=.4) or the quantity of HIV-1 RNA (3.12 vs. 3.00 log(10) copies/swab, P=1.0) in vaginal secretions of women receiving vitamin A, compared with women receiving placebo. No significant effect of supplementation on plasma HIV-1 load or CD4 or CD8 cell counts was observed, and no effect was seen among women who were vitamin A deficient at baseline. Vitamin A supplementation is unlikely to decrease the infectivity of women infected with HIV-1.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , VIH-1/efectos de los fármacos , Esparcimiento de Virus/efectos de los fármacos , Vitamina A/administración & dosificación , Síndrome de Inmunodeficiencia Adquirida/virología , Adolescente , Adulto , Suplementos Dietéticos , Método Doble Ciego , Femenino , Estudios de Seguimiento , VIH-1/fisiología , Humanos , Persona de Mediana Edad , Vagina/virología , Deficiencia de Vitamina A/inmunología
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