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Villamor, Eduardo

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Villamor

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Eduardo

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Villamor, Eduardo
Author's Publications: search.filters.isAuthorOfPublication.0680be18-d5a3-4fcd-a0c0-eeec741e8ea9

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Now showing 1 - 8 of 8
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    Effects of Vitamin A Supplementation on Immune Responses and Correlation with Clinical Outcomes
    (American Society for Microbiology, 2005) Villamor, Eduardo; Fawzi, Wafaie
    Vitamin A supplementation to preschool children is known to decrease the risks of mortality and morbidity from some forms of diarrhea, measles, human immunodeficiency virus (HIV) infection, and malaria. These effects are likely to be the result of the actions of vitamin A on immunity. Some of the immunomodulatory mechanisms of vitamin A have been described in clinical trials and can be correlated with clinical outcomes of supplementation. The effects on morbidity from measles are related to enhanced antibody production and lymphocyte proliferation. Benefits for severe diarrhea could be attributable to the functions of vitamin A in sustaining the integrity of mucosal epithelia in the gut, whereas positive effects among HIV-infected children could also be related to increased T-cell lymphopoiesis. There is no conclusive evidence for a direct effect of vitamin A supplementation on cytokine production or lymphocyte activation. Under certain circumstances, vitamin A supplementation to infants has the potential to improve the antibody response to some vaccines, including tetanus and diphtheria toxoids and measles. There is limited research on the effects of vitamin A supplementation to adults and the elderly on their immune function; currently available data provide no consistent evidence for beneficial effects. Additional studies with these age groups are needed.
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    A Trial of the Effect of Micronutrient Supplementation on Treatment Outcome, T Cell Counts, Morbidity, and Mortality in Adults with Pulmonary Tuberculosis
    (Oxford University Press (OUP), 2008) Villamor, Eduardo; Mugusi, Ferdinand; Urassa, Willy; Bosch, Ronald; Saathoff, Elmar; Matsumoto, Kenji; Meydani, Simin N.; Fawzi, Wafaie
    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 of TB 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.
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    Effect of vitamin supplementation on breast milk concentrations of retinol, carotenoids and tocopherols in HIV-infected Tanzanian women
    (Nature Publishing Group, 2007) Webb, A L; Aboud, S; Furtado, Jeremy; Murrin, C; Campos, Hannia; Fawzi, Wafaie; Villamor, Eduardo
    Background The effect of daily prenatal and postnatal vitamin supplementation on concentrations of breast milk nutrients is not well characterized in HIV-infected women. Objective We examined the impact of vitamin supplementation during pregnancy and lactation on breast milk concentrations of retinol, carotenoids, and tocopherols during the first year post-partum among 626 HIV-infected Tanzanian women. Design We conducted a randomized, double-blind, placebo controlled trial. Women were assigned to one of four daily oral supplements: vitamin A + β-carotene (VA+BC); multivitamins (B, C, E (MV)); MV+VA+BC; or placebo. Concentrations of breast milk nutrients were determined by HPLC at birth and every 3 mo thereafter. Results Supplementation with VA+BC increased concentrations of retinol, β-carotene, and α-carotene at delivery by 4799, 1791, and 84 nmol/L, respectively, compared to no VA+BC (all p<0.0001). MV supplementation did not increase concentrations of α-tocopherol or δ-tocopherol at delivery but significantly decreased concentrations of breast milk γ-tocopherol and retinol. Although concentrations of all nutrients decreased significantly by 3 months postpartum, retinol, α-carotene, and β-carotene concentrations were significantly higher among those receiving VA+BC at 3, 6, and 12 mo compared to no VA+BC. Alpha tocopherol was significantly higher, while γ-tocopherol concentrations were significantly lower, among women receiving MV compared to no MV at 3, 6, and 12 mo post-partum. Conclusions Sustained supplementation of HIV-infected breastfeeding mothers with MV could be a safe and effective intervention to improve vitamin E concentrations in breast milk. VA+BC supplementation increases concentrations of breast milk retinol but it is not recommended in HIV-infected mothers due to the elevated risk of vertical transmission.
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    Predictors of change in nutritional and hemoglobin status among adults treated for tuberculosis in Tanzania
    (International Union Against Tuberculosis and Lung Disease, 2011) Kawai, Kosuke; Villamor, Eduardo; Mugusi, F.M.; Saathoff, E.; Urassa, W.; Bosch, Ronald; Spiegelman, Donna; Fawzi, Wafaie
    BACKGROUND Patients with tuberculosis (TB) often suffer from profound malnutrition. OBJECTIVE To examine the patterns and predictors of change in nutritional and hemoglobin status during and after TB treatment. METHODS A total of 471 HIV-positive and 416 HIV-negative adults with pulmonary TB were prospectively followed in Dar es Salaam, Tanzania. All patients received 8 months TB treatment following enrollment. RESULTS About 40% of HIV-positive and 47% of HIV-negative TB patients had BMI <18.5 kg/m2 at baseline. About 94% of HIV-positive and 84% of HIV-negative participants were anemic at baseline. Both HIV-positive and HIV-negative patients experienced increases in BMI and hemoglobin concentrations over the course of TB treatment. Among HIV-positive patients, older age, low CD4 cell counts, and high viral load were independently associated with a smaller increase in BMI from baseline to 8 months. Female sex, older age, low CD4 cell counts, previous TB infection, and less money spent on food were independently associated with a smaller improvement in hemoglobin among HIV-positive patients during treatment. CONCLUSION HIV- positive TB patients, especially those with low CD4 cell counts, showed poor nutritional recovery during TB treatment. Adequate nutritional support should be considered during TB treatment.
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    Sex differences in the effects of maternal vitamin supplements on mortality and morbidity among children born to HIV-infected women in Tanzania
    (Cambridge University Press (CUP), 2010) Kawai, Kosuke; Msamanga, Gernard; Manji, Karim; Villamor, Eduardo; Bosch, Ronald; Hertzmark, Ellen; Fawzi, Wafaie
    We examined whether there are sex differences in the effect of vitamin supplements on birth outcomes, mortality, and morbidity by two years of age among children born to HIV-infected women in Tanzania. A randomized 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 β-carotene, multivitamins including vitamin A plus β-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 (RR = 0.39, 95% CI 0.22 – 0.67) compared to 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 diarrhea that did not differ by sex. Vitamin A plus β-carotene alone increased the risk of HIV transmission, but had no effect 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.
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    Association between Breast Milk Erythropoietin and Reduced Risk of Mother‐to‐Child Transmission of HIV
    (Oxford University Press (OUP), 2010) Arsenault, Joanne E.; Webb, Aimee L.; Koulinska, Irene N.; Aboud, Said; Fawzi, Wafaie; Villamor, Eduardo
    We examined the prospective associations between breast milk concentrations of erythropoietin, a factor with trophic effects on infant gut epithelia, and risk of MTCT through breastfeeding in a study of 59 MTCT cases and 116 controls nested within a cohort of antiretroviral-naïve HIV-infected Tanzanian women. Controls were matched to cases on the time from birth when the breast milk sample was collected. The risk of MTCT was inversely related to breast milk EPO concentration (adjusted OR for highest vs. lowest EPO tertiles=0.34; 95% CI=0.14, 0.82; P for trend=0.02). These results suggest a protective effect of breast milk EPO against MTCT.
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    Primary Antimicrobial Resistance among Mycobacterium Tuberculosis Isolates from HIV Seropositive and HIV Seronegative Patients in Dar es Salaam Tanzania
    (BioMed Central, 2008) Urassa, Willy; Mugusi, Ferdinand; Villamor, Eduardo; Msamanga, Gernard; Moshiro, Candida; Bosch, Ronald; Saathoff, Elmar; Fawzi, Wafaie
    Background: The United Republic of Tanzania is one of the 22 high M. tuberculosis burden countries. Data collected between 2002 and 2007 indicate that the global prevalence of drug-resistant M. tuberculosis including MDR vary greatly. The varied drug-resistance patterns make continuous surveillance of drug resistance an essential component of tuberculosis control program. Findings: M. tuberculosis isolates were obtained from consenting adult tuberculosis patients involved in a placebo-controlled study to evaluate the efficacy of multivitamin supplements on response to anti-Tb treatment in Dar es Salaam, Tanzania. Antimicrobial susceptibility testing was done on four antimicrobial agents namely streptomycin, isoniazid, ethambutol and rifampicin. HIV testing and CD4+ T lymphocytes enumeration were also done. A total of 280 M. tuberculosis isolates from 191 (68%) males and 89 (32%) female patients with no previous history of anti-tuberculosis treatment exceeding 4 weeks in the previous 12 months were tested. Among these, 133 (47%) patients were HIV seropositive. Fourteen (5.0%) isolates were resistant to any of the anti-tuberculosis drugs. The prevalence of primary resistance was 5.0%, 0.7%, 0.4% and 0% for isoniazid, streptomycin, rifampicin and ethambutol respectively. One isolate (0.4%) was MDR, with resistance to isoniazid, streptomycin and rifampicin. Conclusion: M. Tb primary resistance rate in a selected population in Dar es Salaam Tanzania is low and efforts should be undertaken to support the Tuberculosis program.
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    Factors Associated with Mortality in HIV-Infected and Uninfected Patients with Pulmonary Tuberculosis
    (BioMed Central, 2009) Mugusi, Ferdinand M; Mehta, Saurabh; Villamor, Eduardo; Urassa, Willy; Saathoff, Elmar; Bosch, Ronald; Fawzi, Wafaie
    Background: HIV has fuelled the TB epidemic in sub-Saharan Africa. Mortality in patients co-infected with TB and HIV is high. Managing factors influencing mortality in TB patients might help reducing it. This study investigates factors associated with mortality including patients' HIV sero-status, CD4 cell count, laboratory, nutritional and demographic characteristics in AFB smear positive pulmonary TB patients. Methods: We studied 887 sputum smear positive PTB patients, between 18 and 65 years of age receiving standard 8 months anti-TB treatment. Demographic, anthropometric and laboratory data including HIV, CD4 and other tests were collected at baseline and at regular intervals. Patients were followed for a median period of 2.5 years. Results: Of the 887 participants, 155 (17.5%) died, of whom 90.3% (140/155) were HIV-infected, a fatality of 29.7% (140/471) compared to 3.6% (15/416) among HIV-uninfected. HIV infection, age, low Karnofsky score, CD4 cell counts and hemoglobin, high viral load, and oral thrush were significantly associated with high mortality in all patients. Conclusion: Mortality among HIV-infected TB patients is high despite the use of effective anti-TB therapy. Most deaths occur after successful completion of therapy, an indication that patients die from causes other than TB. HIV infection is the strongest independent predictor of mortality in this cohort.