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1.
Artículo en Inglés | MEDLINE | ID: mdl-21951728

RESUMEN

BACKGROUND: As the current HIV-positive population ages, the absolute number of patients >50 years on treatment is increasing. METHODS: We analyze the differences in treatment outcomes by age category (18-29, 30-39, 40-49, 50-59, and ≥ 60) among 9139 HIV-positive adults initiating ART in South Africa. RESULTS: The adjusted hazard ratios (HRs) for all-cause mortality increased with increasing age, with the strongest association in the first 12 months of follow-up among patients 50 to 59 years (HR 1.67; 95% confidence interval [CI]: 1.24-2.23) versus those <30 years. However, patients 50 to 59 years were less likely to be lost during 24 months on antiretroviral therapy ([ART] HR 0.75; 95% CI: 0.59-0.94) versus patients <30 years. By 6 and 12 months on treatment, older patients were less likely to increase their CD4 count by ≥ 50 cells/mm(3). CONCLUSION: Although older patients are at higher risk of mortality and have poorer immunological responses than their younger counterparts, they are more likely to adhere to care and treatment in the first 24 months on ART.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/mortalidad , Cumplimiento de la Medicación/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , Infecciones por VIH/inmunología , Humanos , Masculino , Persona de Mediana Edad , Sudáfrica/epidemiología , Resultado del Tratamiento , Carga Viral , Adulto Joven
2.
Int J Vitam Nutr Res ; 74(6): 421-34, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15743018

RESUMEN

Ethylene diamine tetraacetic acid (EDTA) is a hexadentate chelator, which can combine with virtually every metal in the periodic table. CaNa2EDTA and Na2EDTA (ADI 2.5 mg EDTA/kg body weight/day) are widely used as sequestering agents in canned products, while NaFeEDTA is a promising iron fortificant. Binding of EDTA with iron is favored in the acid milieu of the stomach, irrespective of whether the EDTA is administered as CaNa2EDTA, Na2EDTA, or NaFeEDTA, but in the more alkaline medium of the duodenum the iron is exchanged, in part, with other metals. The iron released from EDTA is absorbed by the normal physiological mechanisms. When NaFeEDTA is present in a meal, the iron moiety exchanges with the intrinsic food iron and the EDTA partially protects the iron in this common non-heme iron pool from the effects of inhibitors of iron absorption, such as phytates and polyphenols. When iron is added as NaFeEDTA to an inhibitory meal, it is two to three times better absorbed than is iron added as ferrous sulfate. It also has a similar effect on the intrinsic food iron in the meal. Fortification with NaFeEDTA is most efficacious when administered with cereal- and legume-based diets but offers no advantages over other fortificants when added to meals of high bioavailability. Its potential as a fortificant has been confirmed in five extended fortification trials carried out in developing countries. There is no evidence that NaFeEDTA in the dose range proposed for food fortificants (5 to 10 mg iron daily) will have any direct toxic effects. Na2EDTA and CaNa2EDTA have proved safe over a number of years, while the Joint FAO/WHO Expert Committee on Food Additives concluded in 1999 that NaFeEDTA "could be considered safe when used in supervised fortification programs". Animal and human studies, including the results of two fortification trials, suggest that NaFeEDTA has little or no effect on overall zinc metabolism. Indeed, if anything, it increases zinc and possibly copper absorption. Data on potentially toxic metals, such as lead mercury, aluminum, and manganese, are limited but the evidence that is available is uniformly negative thus far. Further studies in this field are desirable. The long-term potential of NaFeEDTA fortification to cause iron overload is conjectural but the available evidence suggests that homeostatic controls would prevent excess iron accumulation in the normal population. NaFeEDTA, which is pale yellow in color, causes fewer organoleptic changes in a number of stored vehicles, including cereals, than do other soluble iron salts. Other potential vehicles include condiments, several of which have been successfully used in fortification trials. What is currently lacking is a consolidated body of published evidence on the stability of NaFeEDTA during processing, storage, and household cooking in widely consumed food vehicles, coupled with standardized testing of consumer acceptance of each fortified vehicle. While NaFeEDTA seems to be an appropriate fortificant for developing countries, its cost is about six to eight times that of ferrous sulfate in terms of equivalent amounts of iron. Its better absorption (a factor of 2-3) might make it possible to halve the daily fortification level but, it still remains expensive and there is a pressing need for food grade NaFeEDTA at more affordable prices. Another possible option is the use of other salts of EDTA (Na2EDTA or Ca Na2EDTA) together with a soluble source of iron, such as ferrous sulfate. The combination has been shown to be as effective as NaFeEDTA when the EDTA:Fe molar ratio is between 1:2 and 1:1. This approach is, however, only feasible with vehicles that are stored for short periods because of ferrous sulfate's propensity to cause organoleptic changes. The search for an iron source that is more stable but at the same time available to combine with EDTA has been unsuccessful thus far. Target populations for fortification with NaFeEDTA include all those that subsist on cereal- and legume-based diets, with the most appropriate vehicles being cereal products and condiments. The fortification of infant milk and cereal formulas with NaFeEDTA does not seem appropriate, since the amounts of NaFeEDTA required for effective fortification would be close to the acceptable daily intake (ADI) of 2.5 mg EDTA/kg body weight/day.


Asunto(s)
Ácido Edético/administración & dosificación , Compuestos Férricos/administración & dosificación , Alimentos Fortificados , Hierro/farmacocinética , Absorción , Disponibilidad Biológica , Ensayos Clínicos como Asunto , Costos y Análisis de Costo , Interacciones Farmacológicas , Ácido Edético/efectos adversos , Ácido Edético/química , Ácido Edético/economía , Grano Comestible , Fabaceae , Compuestos Férricos/efectos adversos , Compuestos Férricos/economía , Humanos , Hierro/administración & dosificación , Hierro/química , Deficiencias de Hierro , Sobrecarga de Hierro
3.
J Womens Health (Larchmt) ; 22(2): 113-20, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23350862

RESUMEN

BACKGROUND: Treatment outcomes for antiretroviral therapy (ART) patients may vary by gender, but estimates from current evidence may be confounded by disease stage and adherence. We investigated the gender differences in treatment response among HIV-positive patients virally suppressed within 6 months of treatment initiation. METHODS: We analyzed data from 7,354 patients initiating ART between April 2004 and April 2010 at Themba Lethu Clinic, a large urban public sector treatment facility in South Africa. We estimated the relations among gender, mortality, and mean CD4 response in HIV-infected adults virally suppressed within 6 months of treatment initiation and used inverse probability of treatment weights to correct estimates for loss to follow-up. RESULTS: Male patients had a 20% greater risk of death at both 24 months and 36 months of follow-up compared to females. Older patients and those with a low hemoglobin level or low body mass index (BMI) were at increased risk of mortality throughout follow-up. Men gained fewer CD4 cells after treatment initiation than did women. The mean differences in CD4 count gains made by women and men between baseline and 12, 24, and 36 months were 28.2 cells/mm(3) (95% confidence interval [CI] 22.2-34.3), 60.8 cells/mm(3) (95% CI 71.1-50.5 cells/mm(3)), and 83.0 cells/mm(3) (95% CI 97.1-68.8 cells/mm(3)), respectively. Additionally, patients with a current detectable viral load (>400 copies/mL) and older patients had a lower mean CD4 increase at the same time points. CONCLUSIONS: In this initially virally suppressed population, women showed consistently better immune response to treatment than did men. Promoting earlier uptake of HIV treatment among men may improve their immunologic outcomes.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/inmunología , Infecciones por VIH/mortalidad , VIH-1/efectos de los fármacos , Adolescente , Adulto , Factores de Edad , Recuento de Linfocito CD4 , Femenino , Estudios de Seguimiento , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Factores Socioeconómicos , Sudáfrica/epidemiología , Factores de Tiempo , Resultado del Tratamiento , Población Urbana , Carga Viral , Adulto Joven
4.
J Acquir Immune Defic Syndr ; 63(4): 442-8, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23614996

RESUMEN

BACKGROUND: The possible impact of coinfection with the Kaposi sarcoma-associated herpes virus (KSHV) on the response to antiretroviral therapy (ART) is unknown. Prospective studies are rare, particularly in Africa. METHODS: We enrolled a prospective cohort of HIV-infected adults initiating ART in Johannesburg, South Africa. The subjects were defined as seropositive to KSHV if they were reactive to either KSHV lytic K8.1 or latent Orf73 antigen or to both. The subjects were followed from ART initiation until 18 months of treatment. HIV viral load and CD4 counts were tested 6 monthly. Linear generalized estimating and log-binomial regression models were used to estimate the effect of KSHV infection on immunologic recovery and response and HIV viral load suppression within 18 months after ART initiation. RESULTS: Three hundred eighty-five subjects initiating ART from November 2008 to March 2009 were considered to be eligible including 184 (48%) KSHV+. The KSHV+ group was similar to the KSHV- in terms of age, gender, initiating CD4 count, body mass index, tuberculosis, and hemoglobin levels. The KSHV+ group gained a similar number of cells at 6 [difference of 10 cells per cubic millimeter, 95% confidence interval (CI): -11 to 31], 12 (3 cells per cubic millimeter, 95% CI: -19 to 25), and 18 months (24 cells per cubic millimeter, 95% CI: -13 to 61) compared with that gained by the KSHV- group. Adjusted relative risk of failure to suppress viral load to <400 copies per milliliter (1.03; 95% CI: 0.90 to 1.17) were similar for KSHV+ and KSHV- by 6 months on treatment. CONCLUSIONS: In a population with a high KSHV prevalence, HIV-positive adults coinfected with KSHV achieved similar immunologic and virologic responses to ART early after treatment initiation compared with those with KSHV-.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por Herpesviridae/complicaciones , Herpesvirus Humano 8/inmunología , Carga Viral , Adulto , Antígenos Nucleares/inmunología , Recuento de Linfocito CD4 , Coinfección , Femenino , Glicoproteínas/inmunología , Infecciones por VIH/inmunología , Infecciones por Herpesviridae/inmunología , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas Virales/inmunología
5.
J Trop Med ; 2013: 162950, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24069036

RESUMEN

Among those with HIV, anemia is a strong risk factor for disease progression and death independent of CD4 count and viral load. Understanding the role of anemia in HIV treatment is critical to developing strategies to reduce morbidity and mortality. We conducted a prospective analysis among 10,259 HIV-infected adults initiating first-line ART between April 2004 and August 2009 in Johannesburg, South Africa. The prevalence of anemia at ART initiation was 25.8%. Mean hemoglobin increased independent of baseline CD4. Females, lower BMI, WHO stage III/IV, lower CD4 count, and zidovudine use were associated with increased risk of developing anemia during follow-up. After initiation of ART, hemoglobin improved, regardless of regimen type and the degree of immunosuppression. Between 0 and 6 months on ART, the magnitude of hemoglobin increase was linearly related to CD4 count. However, between 6 and 24 months on ART, hemoglobin levels showed a sustained overall increase, the magnitude of which was similar regardless of baseline CD4 level. This increase in hemoglobin was seen even among patients on zidovudine containing regimens. Since low hemoglobin is an established adverse prognostic marker, prompt identification of anemia may result in improved morbidity and mortality of patients initiating ART.

6.
Int J Epidemiol ; 42(2): 430-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22434860

RESUMEN

The Themba Lethu Clinical Cohort was established in 2004 to allow large patient-level analyses from a single HIV treatment site to evaluate National Treatment Guidelines, answer questions of national and international policy relevance and to combine an economic and epidemiologic focus on HIV research. The current objectives of the Themba Lethu Clinical Cohort analyses are to: (i) provide cohort-level information on the outcomes of HIV treatment; (ii) evaluate aspects of HIV care and treatment that have policy relevance; (iii) evaluate the cost and cost-effectiveness of different approaches to HIV care and treatment; and (iv) provide a platform for studies on improving HIV care and treatment. Since 2004, Themba Lethu Clinic has enrolled approximately 30,000 HIV-positive patients into its HIV care and treatment programme, over 21,000 of whom have received anti-retroviral therapy since being enrolled. Patients on treatment are typically seen at least every 3 months with laboratory monitoring every 6 months to 1 year. The data collected include demographics, clinical visit data, laboratory data, medication history and clinical diagnoses. Requests for collaborations on analyses can be submitted to our data centre.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Adulto , Fármacos Anti-VIH/administración & dosificación , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Guías de Práctica Clínica como Asunto , Evaluación de Programas y Proyectos de Salud , Factores Socioeconómicos , Sudáfrica/epidemiología , Resultado del Tratamiento , Carga Viral
7.
J Acquir Immune Defic Syndr ; 62(3): e82-6, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23111577

RESUMEN

OBJECTIVES: South African HIV care providers are exploring ways to reduce the intensity of patient visits while maintaining high quality of care. We used routinely collected data to model whether a simple screening tool could identify stable patients who would not need to see a doctor during a scheduled medical visit. DESIGN: We identified stable and nonstable visits from January 2007 to September 2011 at a large HIV clinic in Johannesburg, SA. Stable medical visits were defined as having all of the following: stable CD4 count, undetectable viral load, stable weight, not pregnant, no comorbidity, no regimen change within three months, and normal laboratory results for hemoglobin, alanine aminotransferase, and creatinine clearance. METHODS: We assessed the sensitivity and specificity of nonstable visits at predicting indicators of disease progression or needing additional care: (1) ART regimen change and (2) follow-up visits in <2 and <4 weeks from previous visit. RESULTS: Stable visits had a sensitivity of 88.9% (95% confidence interval: 88.2 to 89.7) and a specificity of 44.8% (44.5 to 44.1) at predicting ART therapy changes, and a sensitivity of 72.6% (71.8 to 73.4) and specificity of 45.1% (44.8 to 45.4) for predicting a follow-up visit interval of <2 weeks and similar results for predicting a follow-up visit interval of <4 weeks. CONCLUSIONS: Our retrospective analysis suggests an approach to potentially reduce the number of medical visits while missing few visits in which changes in regimen or additional care would be needed. Evaluation of our criteria in a primary care setting is needed to determine whether they could safely reduce visits.


Asunto(s)
Infecciones por VIH/diagnóstico , Tamizaje Masivo/métodos , Adulto , Atención Ambulatoria/estadística & datos numéricos , Terapia Antirretroviral Altamente Activa , Biomarcadores/análisis , Recuento de Linfocito CD4 , Progresión de la Enfermedad , Estudios de Factibilidad , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Masculino , Estudios Retrospectivos , Sensibilidad y Especificidad , Sudáfrica , Carga Viral
8.
Infect Agent Cancer ; 6: 22, 2011 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-22093140

RESUMEN

BACKGROUND: Kaposi sarcoma (KS) is the most common AIDS-defining tumour in HIV-infected individuals in Africa. Kaposi sarcoma herpes virus (KSHV) infection precedes development of KS. KSHV co-infection may be associated with worse outcomes in HIV disease and elevated KSHV viral load may be an early marker for advanced HIV disease among untreated patients. We examined the prevalence of KSHV among adults initiating antiretroviral therapy (ART) and compared immunological, demographic and clinical factors between patients seropositive and seronegative for KSHV. RESULTS: We analyzed cross-sectional data collected from 404 HIV-infected treatment-naïve adults initiating ART at the Themba Lethu Clinic, Johannesburg, South Africa between November 2008 and March 2009. Subjects were screened at ART initiation for antibodies to KSHV lytic K8.1 and latent Orf73 antigens. Seropositivity to KSHV was defined as positive to either lytic KSHV K8.1 or latent KSHV Orf73 antibodies. KSHV viremia was determined by quantitative PCR and CD3, 4 and 8 lymphocyte counts were determined with flow cytometry. Of the 404 participants, 193 (48%) tested positive for KSHV at ART initiation; with 76 (39%) reactive to lytic K8.1, 35 (18%) to latent Orf73 and 82 (42%) to both. One individual presented with clinical KS at ART initiation. The KSHV infected group was similar to those without KSHV in terms of age, race, gender, ethnicity, smoking and alcohol use. KSHV infected individuals presented with slightly higher median CD3 (817 vs. 726 cells/mm3) and CD4 (90 vs. 80 cells/mm3) counts than KSHV negative subjects. We found no associations between KSHV seropositivity and body mass index, tuberculosis status, WHO stage, HIV RNA levels, full blood count or liver function tests at initiation. Those with detectable KSHV viremia (n = 19), however, appeared to present with signs of more advanced HIV disease including anemia and WHO stage 3 or 4 defining conditions compared to those in whom the virus was undetectable. CONCLUSIONS: We demonstrate a high prevalence of KSHV among HIV-infected adults initiating ART in a large urban public-sector HIV clinic. KSHV viremia but not KSHV seropositivity may be associated with markers of advanced HIV disease.

9.
J Gastroenterol Hepatol ; 20(12): 1855-8, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16336444

RESUMEN

BACKGROUND: Dietary iron overload found in sub-Saharan Africa might be caused by an interaction between dietary iron and an iron-loading gene. Caucasian people with ferroportin gene mutations have iron overload histologically similar to that found in African patients with iron overload. Ferroportin is also implicated in the hypoferremic response to inflammation. The prevalence of the ferroportin Q248H mutation, unique to African people, and its association with dietary iron overload, mean cell volume (MCV) and C-reactive protein (CRP) were examined in 19 southern African families. METHODS: Polymerase chain reaction (PCR) and restriction enzyme digestion were used to identify the Q248H mutation. Statistical analysis was carried out to correlate the presence of the mutation with markers of iron overload and inflammation. RESULTS: We identified three (1.4%) Q248H homozygotes and 53 (24.1%) heterozygotes in the families examined in the present study. There was no increased prevalence of the mutation in index subjects or their families. Logistic regression showed significantly higher serum ferritin concentrations with the mutation. The mean cell volume (MCV) was significantly lower, and the serum CRP significantly higher in subjects who carried the mutation. CONCLUSIONS: The present study of 19 families with African iron overload failed to show evidence that the ferroportin (Q248H) mutation is responsible for the condition. Logistic regression, correcting for factors influencing iron status, did show increased ferritin levels in individuals with the mutation. The strong association with low MCV suggests the possibility that the ferroportin (Q248H) mutation might interfere with iron supply, whereas the elevated serum CRP might indicate that the ferroportin mutation influences the inflammatory response in African populations.


Asunto(s)
Población Negra/genética , Proteínas de Transporte de Catión/sangre , Sobrecarga de Hierro/genética , Mutación , Biomarcadores/sangre , Proteína C-Reactiva/genética , Distribución de Chi-Cuadrado , Femenino , Humanos , Sobrecarga de Hierro/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prevalencia , Sudáfrica/epidemiología
10.
Endocrine ; 21(3): 241-4, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14515008

RESUMEN

Endocrine disturbances, notably diabetes, have been well described as a complication of iron overload due to hereditary hemochromatosis and beta-thalassemia. Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis has also been well documented. The pattern of iron loading in African iron overload with saturated transferrin is similar to that seen in hereditary hemochromatosis. In addition, many symptoms ascribed to pituitary dysfunction are common to both conditions. The present study was undertaken to assess whether a similar pattern of endocrine dysfunction occurs in African iron overload. Thirty subjects with African iron overload and transferrin saturation >50%, plus 30 age and sex matched normal controls were studied. An iron profile, fasting plasma glucose, cortisol, DHEA-S, LH, FSH, growth hormone, prolactin, TSH, and FT4 levels were measured in all 60 subjects as well as testosterone in the males and estradiol in the females. Iron loading in the subjects with increased transferrin saturation ranged from moderate to severe. No significant differences were found in the mean testosterone, estradiol, LH, DHEA-S, growth hormone, prolactin, or TSH levels between the subjects and normal controls. In female subjects, although within the normal range, the mean FSH level was significantly higher, probably due to their being somewhat older and in a more advanced stage of menopause than the control females. Mean cortisol concentrations were increased in both genders in the patient group, significantly so in the females; however, values were within the reference range. We conclude therefore that there appears to be no major impairment of endocrine function in the basal state in African iron overload subjects with moderate to severe degrees of iron loading.


Asunto(s)
Glucemia/metabolismo , Hormonas/sangre , Sobrecarga de Hierro/sangre , Hierro de la Dieta/efectos adversos , Hierro/sangre , África , Sulfato de Deshidroepiandrosterona/sangre , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Hormona del Crecimiento/sangre , Humanos , Hidrocortisona/sangre , Sobrecarga de Hierro/etiología , Hormona Luteinizante/sangre , Masculino , Persona de Mediana Edad , Prolactina/sangre , Testosterona/sangre , Tirotropina/sangre
11.
Arch. latinoam. nutr ; 51(1,supl.1): 2-6, mar. 2001.
Artículo en Inglés | LILACS | ID: lil-333621

RESUMEN

The dietary intake of iron in underdeveloped countries is based mainly on non-hem iron which is absorbed to a lesser degree that hem iron and is subjected to many interferences from inhibitors generally present in the diets, such as phenols, phytates, fibers, etc. Food fortification with iron is considered to be the best and cheapest long-term approach for correcting the deficiency. The iron source selected for this purpose has to be soluble, and of high bioavailability, even in a diet rich in inhibitors. Ferrochel may prove to be this type of compound.


Asunto(s)
Femenino , Humanos , Masculino , Países en Desarrollo , Hierro , Anemia Ferropénica , Alimentos Fortificados , Hierro , Hierro de la Dieta
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