Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Am J Gastroenterol ; 118(7): 1214-1225, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36599136

RESUMEN

INTRODUCTION: Hepatitis B surface antigen (HBsAg) loss is associated with improved long-term outcomes of patients with chronic hepatitis B but is infrequently achieved with current monotherapies. We assessed whether combination strategies that included treatment withdrawal enhanced HBsAg loss. METHODS: A randomized (1:1) trial of tenofovir disoproxil fumarate (TDF) for 192 weeks with or without peginterferon (PegIFN) alfa-2a for the first 24 weeks, followed by withdrawal of TDF at week 192 with 48 weeks of off-treatment follow-up to week 240. The primary end point was HBsAg loss at week 240. RESULTS: Of 201 participants (52% HBeAg positive, 12%/6% genotype A/A2, 7% cirrhosis) randomized to TDF + PegIFN (n = 102) or TDF alone (n = 99), 6 participants had lost HBsAg at the end of the treatment phase (week 192), 5 (5.3%) in the combination group, and 1 (1.0%) in the TDF alone group ( P = 0.09). By week 240, 9 participants had cleared HBsAg, 5.3% in combination, and 4.1% in monotherapy arms ( P = 0.73). HBsAg decline and loss occurred earlier with TDF + PegIFN than TDF, with a ≥1-logIU/mL qHBsAg decline by week 24 in 28% in TDF + PegIFN compared with 6% in TDF ( P = 0.04). HBsAg loss occurred in 7 of 12 (58%) with hepatitis B virus subgenotype A2 (all HBeAg positive) compared with only 2 of 189 (1%) with other hepatitis B virus genotypes and in 8 of 93 (8.6%) HBeAg positive vs 1 of 87 (1.1%) HBeAg negative. DISCUSSION: PegIFN combined TDF followed by protocolized TDF withdrawal led to earlier but not higher percentages of HBsAg clearance. Pretreatment HBeAg positivity and subgenotype A2 were strongly associated with HBsAg clearance.


Asunto(s)
Hepatitis B Crónica , Humanos , Adulto , Tenofovir/uso terapéutico , Antivirales , Antígenos de Superficie de la Hepatitis B , Antígenos e de la Hepatitis B , Resultado del Tratamiento , Virus de la Hepatitis B/genética , Polietilenglicoles/uso terapéutico , ADN Viral
2.
J Hepatol ; 57(5): 946-52, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22760009

RESUMEN

BACKGROUND & AIMS: Fatigue is the most frequent and often debilitating symptom of chronic hepatitis C. It is unclear whether successful therapy of hepatitis C leads to its clinical improvement. In the Virahep-C study, patients with hepatitis C virus (HCV) genotype 1 infection were treated with peginterferon alfa-2a and ribavirin for up to 48 weeks while undergoing assessment of viral kinetics and clinical symptoms. METHODS: Fatigue measurements were conducted, before, during and after therapy, as 'presence' (yes/no) and 'severity' (visual analog scale: 0-100mm). The clinical, histologic, and virologic features that correlated with the presence and degree of fatigue were assessed focusing upon changes associated with sustained virological response (SVR). RESULTS: At baseline, 52% (n=401) of participants reported having fatigue, which was more common in women than men (59% vs. 48%, p=0.02) and slightly more severe (30 vs. 22 mm, p=0.056). Fatigue was frequent and worse in cirrhotics versus those with lesser fibrosis (66% vs. 49%; 34 vs. 24 mm). Fatigue did not correlate with other parameters. The proportion of patients and median fatigue scores increased on treatment (52-78%; 25-40 mm, p<0.0001) with higher fatigue noted amongst those who ultimately achieved SVR (p<0.0001). On achieving SVR, there was a significant decrease in both frequency and severity of fatigue compared to their baseline (53-33%; 27-13 mm, both p<0.0001). CONCLUSIONS: Fatigue is common in patients with chronic hepatitis C but is poorly associated with biochemical parameters. Sustained response is accompanied by substantial improvement of fatigue.


Asunto(s)
Antivirales/uso terapéutico , Fatiga/epidemiología , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Adulto , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Genotipo , Hepacivirus/genética , Humanos , Estudios Longitudinales , Masculino , Prevalencia , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
3.
Gastroenterology ; 140(2): 469-77, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21070775

RESUMEN

BACKGROUND & AIMS: Chronic hepatitis C is associated with an increased prevalence of insulin resistance, which might result from liver disease, metabolic factors, or the hepatitis C virus (HCV) itself. The effect of antiviral treatment on insulin sensitivity is not well-known. We evaluated changes in insulin resistance and weight in patients with hepatitis C during and after peginterferon and ribavirin therapy. METHODS: Virahep-C was a prospective, multicenter study of a 48-week course of combination antiviral therapy in patients infected with HCV genotype 1. Insulin resistance (IR) was estimated by the homeostasis model assessment index (HOMA2-IR) based on fasting glucose and insulin levels. RESULTS: Among 341 patients, 40% had insulin resistance (HOMA2-IR > 2.0). The presence of insulin resistance was associated with increasing age, body mass index (BMI), and fibrosis stage. Among patients with insulin resistance at the start of the trial, median decreases in HOMA2-IR values during treatment were 0.74 at 24 weeks and 0.89 at 48 weeks, whereas BMI decreased by 1.2 and 2.2 at the same time points (P < .001 for all). At follow-up, HOMA2-IR and BMI levels returned toward baseline values in patients who did not respond or relapsed, but HOMA2-IR values remained significantly lower in patients with sustained virologic response (SVR) (P < .001), despite increases in BMI. CONCLUSIONS: In patients with HCV genotype 1 infections, therapy with peginterferon and ribavirin is associated with decreases in body weight and insulin resistance. Among patients with insulin resistance before treatment, resolution of HCV infection results in sustained improvements in the HOMA-IR index, suggesting that HCV could have a direct role in the pathogenesis of insulin resistance.


Asunto(s)
Antivirales/uso terapéutico , Peso Corporal/efectos de los fármacos , Resistencia a la Insulina , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Adulto , Factores de Edad , Índice de Masa Corporal , Ensayos Clínicos como Asunto , Quimioterapia Combinada , Femenino , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Interferón alfa-2 , Masculino , Estudios Multicéntricos como Asunto , Proteínas Recombinantes
4.
Hepatology ; 52(3): 854-63, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20690192

RESUMEN

UNLABELLED: Approximately one half of patients who undergo antiviral therapy for chronic hepatitis C virus (HCV) genotype 1 infection do not respond to treatment. African Americans (AAs) are less responsive to treatment than Caucasian Americans (CAs), but the reasons for this disparity are largely unknown. Recent studies suggest that serum lipids may be associated with treatment response. The aims of this study were to evaluate baseline and changes in serum lipids during therapy, determine whether serum lipids are associated with virological response, and assess whether these measures explain the racial difference in efficacy. The study participants were from Virahep-C, a prospective study of treatment-naïve patients with genotype 1 HCV infection who received peginterferon (PEG-IN) alfa-2a plus ribavirin therapy for up to 48 weeks. Fasting serum lipids were analyzed at baseline and during and after therapy in 160 AAs and 170 CAs. A relative risk (RR) model was employed to evaluate characteristics associated with sustained virological response (SVR). Antiviral therapy was associated with changes in serum lipids during and after antiviral therapy, with the changes differing by race and the amount of PEG-IFN taken. Baseline lipid measures independently associated with higher rates of SVR were lower triglyceride and higher low-density lipoprotein cholesterol, with an interaction between high-density lipoprotein cholesterol (HDLc) and gender. Lipid measures did not contribute significantly to an explanation of the racial difference in SVR. CONCLUSION: Serum lipids are associated with SVR, although these paramaters did not explain the racial difference in treatment response. The results of this study are compatible with proposed biological mechanisms of HCV entry, replication, and secretion, and may underscore new potential therapeutic targets for HCV eradication.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Lípidos/sangre , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Adulto , Negro o Afroamericano , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Estudios de Cohortes , Quimioterapia Combinada , Femenino , Genotipo , Hepacivirus/genética , Hepatitis C Crónica/sangre , Hepatitis C Crónica/etnología , Humanos , Interferón alfa-2 , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas Recombinantes , Estudios Retrospectivos , Resultado del Tratamiento , Triglicéridos/sangre , Población Blanca
5.
Gastroenterology ; 137(3): 873-84, 884.e1, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19527724

RESUMEN

BACKGROUND & AIMS: The recommended therapy for chronic hepatitis C, pegylated interferon and ribavirin for 24 or 48 weeks, has many known adverse side effects. The aim of this study was to evaluate the impact of antiviral therapy on male sexual health. METHODS: As part of the Study of Viral Resistance to Antiviral Therapy of Chronic Hepatitis C (Virahep-C), 260 men treated with pegylated interferon alfa-2a and ribavirin completed self-administered questionnaires concerning sexual desire, sexual function, including erectile and ejaculatory function, and sexual satisfaction before, during, and after treatment. RESULTS: Before therapy, 37% of men reported at least some degree of impairment in sexual desire and 44% reported dissatisfaction with their sexual life, while 26% reported impairment in erectile and 22% in ejaculatory function. During therapy, significant declines were observed in all components of sexual health compared with pretreatment. At the end of therapy (24 or 48 weeks), an estimated 38%-48% of men reported that overall sexual function was worse than before treatment. African American patients reported less impairment in sexual desire and satisfaction than Caucasian American patients during therapy. By 24 weeks after treatment, sexual desire and satisfaction improved and were comparable to baseline levels. However, among men who received 48 weeks of therapy, the estimated percentage of men reporting posttreatment erectile or ejaculatory problems remained higher than baseline, although persistent erectile impairment was limited to Caucasian American patients. CONCLUSIONS: Sexual impairment is common among men with chronic hepatitis C undergoing therapy with pegylated interferon and ribavirin and should be considered as a potential side effect of antiviral therapy.


Asunto(s)
Antivirales/efectos adversos , Disfunción Eréctil/inducido químicamente , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/efectos adversos , Libido/efectos de los fármacos , Polietilenglicoles/efectos adversos , Ribavirina/efectos adversos , Adulto , Antivirales/administración & dosificación , Población Negra , Quimioterapia Combinada , Eyaculación/efectos de los fármacos , Disfunción Eréctil/etnología , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Proteínas Recombinantes , Ribavirina/administración & dosificación , Encuestas y Cuestionarios , Población Blanca
6.
Clin Gastroenterol Hepatol ; 6(5): 575-83, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18407798

RESUMEN

BACKGROUND & AIMS: The relationship between serum peginterferon pharmacokinetics and pharmacodynamics and the early virologic response (EVR) to peginterferon and ribavirin therapy was assessed in patients with chronic hepatitis C virus (HCV) genotype 1 infection. METHODS: A total of 333 patients (160 African Americans [AA] and 173 Caucasian Americans [CA]) who received peginterferon alpha-2a (180 microg/wk) without a dose modification during the initial 4 weeks of therapy were analyzed. Peginterferon and 2,5-oligoadenylate synthetase (2,5-OAS) serum levels were measured on days 0, 1, 2, 3, 7, 14, 28, 56, 84, and 168 of treatment. The EVR (>or=2-log(10) decline in HCV RNA levels by week 12 of therapy) was the primary virologic end point. RESULTS: Peginterferon pharmacokinetics after the first dose were similar in AA and CA, but AA had greater peginterferon concentrations at days 1, 3, 14, and 28 (P < .05). AA had higher absolute serum 2,5-OAS levels on days 0, 1, 2, 3, 7, 14, 28, and 56 (P < .05), but the magnitude of 2,5-OAS induction during treatment were similar. AA patients showed a smaller decline in serum HCV RNA during the first 28 days of treatment (P < .001) and a lower EVR (65% vs 83%). AA and CA with EVR had significantly higher serum peginterferon concentrations and serum 2,5-OAS induction during the first 12 weeks than patients without an EVR. CONCLUSIONS: Peginterferon alpha-2a pharmacokinetic and pharmacodynamic variability is associated with EVR in both AA and CA with HCV infection, but do not explain the racial disparity in combination treatment efficacy.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/etnología , Interferón-alfa/farmacocinética , Polietilenglicoles/farmacocinética , Población Blanca/estadística & datos numéricos , Adolescente , Adulto , Anciano , Área Bajo la Curva , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Genotipo , Hepacivirus/genética , Hepatitis C Crónica/sangre , Humanos , Inyecciones Subcutáneas , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , ARN Viral/efectos de los fármacos , Proteínas Recombinantes , Ribavirina/administración & dosificación , Ribavirina/farmacocinética , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Resultado del Tratamiento , Carga Viral
7.
Surg Obes Relat Dis ; 11(2): 313-20, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25595919

RESUMEN

BACKGROUND: Anastomotic leak is one of the most serious complications after Roux-en-Y gastric bypass (RYGB). Our objective was to examine the relationship between technical factors and incidence of clinically relevant anastomotic leak after RYGB in longitudinal assessment of bariatric surgery (LABS). The setting of the study was 11 bariatric centers in the United States, university, and private practice. METHODS: Patient characteristics, technical factors of surgery, and postoperative outcomes were assessed by trained researchers using standardized protocols. Correlation of surgical factors of patients undergoing RYGB (n = 4444) with the incidence of postoperative anastomotic leak was assessed by univariate χ(2) analysis. RESULTS: Forty-four participants (1.0%, 95% CI .7%-1.3%) experienced a clinically relevant anastomotic leak. Of these, 39 (89%) underwent abdominal reoperation and 3 (7%) died. Technical factors associated with anastomotic leak were open surgery (P<.0001), revision surgery (P<.0001), and use of an abdominal drain (P = .02). Provocative leak testing, method of gastrojejunostomy, and use of fibrin sealant were not associated with anastomotic leak. CONCLUSIONS: Anastomotic leak after RYGB was rare (1.0%). Most cases required reintervention; however, the majority (93%) recovered from this event. Open surgery, revision surgery, and routine drain placement were associated with increased leak rate. Some of these findings may be due to differences in preoperative patient risk.


Asunto(s)
Fuga Anastomótica/cirugía , Derivación Gástrica/efectos adversos , Laparoscopía/métodos , Obesidad Mórbida/cirugía , Adhesivos Tisulares/uso terapéutico , Adulto , Anciano , Fuga Anastomótica/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Reoperación , Estados Unidos/epidemiología
8.
Surg Obes Relat Dis ; 9(5): 623-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23274125

RESUMEN

BACKGROUND: The existence of a relationship between surgeon volume and patient outcome has been reported for different complex surgical operations. This relationship has also been confirmed for patients undergoing Roux-en-Y gastric bypass (RYGB) in the Longitudinal Assessment of Bariatric Surgery (LABS) study. Despite multiple studies demonstrating volume-outcome relationships, fewer studies investigate the causes of this relationship. OBJECTIVE: The purpose of the present study is to understand possible explanations for the volume-outcome relationship in LABS. METHODS: LABS includes a 10-center, prospective study examining 30-day outcomes after bariatric surgery. The relationship between surgeon annual RYGB volume and incidence of a composite endpoint (CE) has been published previously. Technical aspects of RYGB surgery were compared between high and low volume surgeons. The previously published model was adjusted for select technical factors. RESULTS: High-volume surgeons (>100 RYGBs/yr) were more likely to perform a linear stapled gastrojejunostomy, use fibrin sealant, and place a drain at the gastrojejunostomy compared with low-volume surgeons (<25 RYGBs/yr), and less likely to perform an intraoperative leak test. After adjusting for the newly identified technical factors, the relative risk of CE was .93 per 10 RYGB/yr increase in volume, compared with .90 for clinical risk adjustment alone. CONCLUSION: High-volume surgeons exhibited certain differences in technique compared with low-volume surgeons. After adjusting for these differences, the strength of the volume-outcome relationship previously found was reduced only slightly, suggesting that other factors are also involved.


Asunto(s)
Derivación Gástrica/métodos , Obesidad/cirugía , Evaluación de Procesos y Resultados en Atención de Salud , Pautas de la Práctica en Medicina/estadística & datos numéricos , Adulto , Drenaje/métodos , Determinación de Punto Final , Femenino , Humanos , Masculino , Estudios Prospectivos , Adhesivos Tisulares/uso terapéutico , Estados Unidos , Carga de Trabajo
9.
PLoS One ; 5(2): e9032, 2010 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-20140258

RESUMEN

BACKGROUND: Hepatitis C virus (HCV) has six major genotypes, and patients infected with genotype 1 respond less well to interferon-based therapy than other genotypes. African American patients respond to interferon alpha-based therapy at about half the rate of Caucasian Americans. The effect of HCV's genetic variation on treatment outcome in both racial groups is poorly understood. METHODOLOGY: We determined the near full-length pre-therapy consensus sequences from 94 patients infected with HCV genotype 1a or 1b undergoing treatment with peginterferon alpha-2a and ribavirin through the Virahep-C study. The sequences were stratified by genotype, race and treatment outcome to identify HCV genetic differences associated with treatment efficacy. PRINCIPAL FINDINGS: HCV sequences from patients who achieved sustained viral response were more diverse than sequences from non-responders. These inter-patient diversity differences were found primarily in the NS5A gene in genotype 1a and in core and NS2 in genotype 1b. These differences could not be explained by host selection pressures. Genotype 1b but not 1a African American patients had viral genetic differences that correlated with treatment outcome. CONCLUSIONS & SIGNIFICANCE: Higher inter-patient viral genetic diversity correlated with successful treatment, implying that there are HCV genotype 1 strains with intrinsic differences in sensitivity to therapy. Core, NS3 and NS5A have interferon-suppressive activities detectable through in vitro assays, and hence these activities also appear to function in human patients. Both preferential infection with relatively resistant HCV variants and host-specific factors appear to contribute to the unusually poor response to therapy in African American patients.


Asunto(s)
Hepacivirus/genética , Hepatitis C/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Adulto , Negro o Afroamericano/estadística & datos numéricos , Antivirales/uso terapéutico , Quimioterapia Combinada , Femenino , Frecuencia de los Genes , Variación Genética , Genoma Viral , Genotipo , Hepacivirus/clasificación , Hepatitis C/etnología , Hepatitis C/genética , Humanos , Interferón alfa-2 , Masculino , MicroARNs/genética , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Filogenia , Proteínas Recombinantes , Ribavirina/uso terapéutico , Proteínas del Núcleo Viral/genética , Proteínas no Estructurales Virales/genética , Población Blanca/estadística & datos numéricos
10.
J Infect Dis ; 199(8): 1112-20, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-19284286

RESUMEN

Early changes in hepatitis C virus (HCV) RNA levels were assessed in a large cohort of African American and white patients with chronic hepatitis C due to HCV genotype 1 who underwent therapy with peginterferon alfa-2a and ribavirin in the Study of Viral Resistance to Antiviral Therapy of Hepatitis C (Virahep-C). Analyses were restricted to 341 patients who completed the first 28 days of therapy without dose modification. HCV RNA levels decreased in virtually all patients, but the amount of the change varied markedly. The overall 28-day decrease in HCV RNA levels was at least as predictive of a sustained virological response as the first- or second-phase viral kinetics responses. Factors associated with a smaller decrease in the HCV RNA level between baseline and day 28 included African American race, higher initial HCV RNA level, more severe hepatic fibrosis, and higher body weight. African American patients with similar 28-day decreases in viral levels as white patients were still less likely to achieve a sustained virological response. These results suggest that racial differences in the response to antiviral therapy are due to greater unresponsiveness to intracellular actions of interferon in African American individuals and that standard doses of peginterferon and ribavirin may be suboptimal for patients with higher body weights. Trial registration. ClinicalTrials.gov identifier: NCT00038974 .


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , ARN Viral/sangre , Ribavirina/uso terapéutico , Negro o Afroamericano , Antivirales/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Genotipo , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Hepatitis C Crónica/genética , Hepatitis C Crónica/virología , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Proteínas Recombinantes , Ribavirina/administración & dosificación , Población Blanca
11.
Hepatology ; 45(1): 80-7, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17187406

RESUMEN

UNLABELLED: Hepatic steatosis is common in chronic hepatitis C and has been linked to concurrent obesity, insulin resistance, diabetes, disease severity, and poor response to therapy. Racial differences in rates of obesity and diabetes may contribute to racial differences in hepatic steatosis and treatment response. The aim of the present study was to compare hepatic steatosis and its associations between African American (AA) and Caucasian American (CA) patients with chronic hepatitis C, genotype 1, participating in a prospective study of peginterferon and ribavirin therapy. Liver biopsy results were available from 194 AA patients and 205 CA patients. The 2 groups were compared for anthropometric, clinical, and biochemical features and insulin resistance estimated by the homeostasis model assessment index (HOMA-IR). Sixty-one percent of the AA patients and 65% of the CA patients had hepatic steatosis (P = 0.38). In univariable analysis, steatosis was associated with HOMA-IR, body mass index, waist circumference, serum triglycerides, aminotransferase level, and histological scores for inflammation and fibrosis. After adjusting for these features, AA patients had a lower risk of steatosis than did CA patients (OR 0.54, 95% CI 0.32-0.91, P = 0.02). Insulin resistance but not steatosis was associated with a lower rate of sustained virological response when adjusted for known factors that predict response (relative risk 0.87, 95% CI 0.77-0.99, P = 0.028). CONCLUSION: After adjusting for the higher prevalence of features associated with hepatic steatosis, AA patients had a lower prevalence of hepatic steatosis than did CA patients with chronic hepatitis C, genotype 1. Insulin resistance but not steatosis was independently associated with lower sustained virological response.


Asunto(s)
Negro o Afroamericano/genética , Hígado Graso/etnología , Hígado Graso/genética , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/etnología , Resistencia a la Insulina/genética , Población Blanca/genética , Adulto , Antivirales/uso terapéutico , Quimioterapia Combinada , Hígado Graso/epidemiología , Femenino , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Resistencia a la Insulina/etnología , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Análisis Multivariante , Polietilenglicoles/uso terapéutico , Prevalencia , Estudios Prospectivos , Proteínas Recombinantes , Ribavirina/uso terapéutico , Índice de Severidad de la Enfermedad , Transducción de Señal
12.
J Virol ; 81(15): 8211-24, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17522222

RESUMEN

Pegylated alpha interferon and ribavirin therapy for hepatitis C virus (HCV) genotype 1 infection fails for half of Caucasian American patients (CA) and more often for African Americans (AA). The reasons for these low response rates are unknown. HCV is highly genetically variable, but it is unknown how this variability affects response to therapy. To assess effects of viral diversity on response to therapy, the complete pretreatment genotype 1 HCV open reading frame was sequenced using samples from 94 participants in the Virahep-C study. Sequences from patients with >3.5 log declines in viral RNA levels by day 28 (marked responders) were more variable than those from patients with declines of <1.4 log (poor responders) in NS3 and NS5A for genotype 1a and in core and NS3 for genotype 1b. These correlations remained when all T-cell epitopes were excluded, indicating that these differences were not due to differential immune selection. When the sequences were compared by race of the patients, higher diversity in CA patients was found in E2 and NS2 but only for genotype 1b. Core, NS3, and NS5A can block the action of alpha interferon in vitro; hence, these genetic patterns are consistent with multiple amino acid variations independently impairing the function of HCV proteins that counteract interferon responses in humans, resulting in HCV strains with variable sensitivity to therapy. No evidence was found for novel HCV strains in the AA population, implying that AA patients may be infected with a higher proportion of the same resistant strains that are found in CA patients.


Asunto(s)
Variación Genética , Hepacivirus/genética , Hepatitis C/terapia , Sistemas de Lectura Abierta , Adulto , Negro o Afroamericano/genética , Secuencia de Aminoácidos , Antivirales/metabolismo , Antivirales/uso terapéutico , Portadores de Fármacos/metabolismo , Hepacivirus/metabolismo , Humanos , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes , Ribavirina/uso terapéutico , Alineación de Secuencia , Análisis de Secuencia de ADN , Población Blanca/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA