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1.
Environ Health Perspect ; 132(4): 47003, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38573329

RESUMO

BACKGROUND: Hypertension is a major cause of death worldwide. Although arsenic exposure has been associated with the risk of hypertension, this association appears nonuniform due to inconsistent results from studies conducted in different populations. Moreover, hypertension is a complex condition with multiple underlying mechanisms and factors. One factor is impaired production and bioavailability of vascular nitric oxide (NO). However, the implications of the effects of arsenic exposure on circulating NO and its association with hypertension in humans are largely unknown. OBJECTIVE: We investigated the dose-response relationship between arsenic exposure and hypertension with vascular NO levels as a potential mediator of arsenic-related hypertension in individuals exposed to a broad range of arsenic. METHODS: A total of 828 participants were recruited from low- and high-arsenic exposure areas in Bangladesh. Participants' drinking water, hair, and nail arsenic concentrations were measured by inductively coupled plasma mass spectroscopy. Hypertension was defined as a systolic blood pressure (SBP) value of ≥140 and a diastolic (DBP) value of ≥90 mmHg. Serum NO levels reflected by total serum nitrite concentrations were measured by immunoassay. A formal causal mediation analysis was used to assess NO as a mediator of the association between arsenic level and hypertension. RESULTS: Increasing concentrations of arsenic measured in drinking water, hair, and nails were associated with the increasing levels of SBP and DBP. The odds of hypertension were dose-dependently increased by arsenic even in participants exposed to relatively low to moderate levels (10-50µg/L) of water arsenic [odds ratios (ORs) and 95% confidence intervals (CIs): 2.87 (95% CI: 1.28, 6.44), 2.67 (95% CI: 1.27, 5.60), and 5.04 (95% CI: 2.71, 9.35) for the 10-50µg/L, 50.01-150µg/L, and >150µg/L groups, respectively]. Causal mediation analysis showed a significant mediating effect of NO on arsenic-related SBP, DBP, and hypertension. CONCLUSION: Increasing exposure to arsenic was associated with increasing odds of hypertension. The association was mediated through the reduction of vascular NO bioavailability, suggesting that impaired NO bioavailability was a plausible underlying mechanism of arsenic-induced hypertension in this Bangladeshi population. https://doi.org/10.1289/EHP13018.


Assuntos
Arsênio , Água Potável , Hipertensão , Humanos , Disponibilidade Biológica , Arsênio/toxicidade , Óxido Nítrico , Bangladesh/epidemiologia , Hipertensão/induzido quimicamente , Hipertensão/epidemiologia
2.
Dig Dis Sci ; 68(12): 4499-4510, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37804353

RESUMO

AIMS: Evaluate patient-reported liver symptoms during treatment for chronic hepatitis B viral (HBV) infection and associations between changes in symptoms and levels of alanine aminotransferase (ALT) and viral markers. METHODS: Data from 200 participants in the Hepatitis B Research Network Immune Active Trial who completed symptom assessments were analyzed. Patients were treated with tenofovir, with or without peginterferon (TDF + PegIFN vs. TDF alone) for 192 weeks. Participants completed a Symptom Checklist at baseline and every 4-12 weeks. A total symptom score was created, ranging from 0 (none) to 40 (severe). The SF-36 was completed every 48 weeks. Associations of symptom scores with ALT and viral markers were evaluated at baseline and end of treatment. RESULTS: Participants were 65% male, 83% Asian, with a mean age of 42. Baseline symptoms were mild (median = 2, range 0-25) and associated with baseline ALT, HBV DNA levels and HBeAg + status. Patients on TDF alone experienced a more rapid and greater improvement in symptoms, but by week 192, symptom improvement was similar in both groups (54% vs 36%). Symptom improvements correlated with ALT and HBV DNA, most markedly among those with symptoms at baseline. Most patients (4 out of 6) who achieved HBsAg loss experienced symptom improvements. Overall, SF-36 scores did not change with treatment. CONCLUSIONS: Reduction in ALT and HBV DNA levels with therapy are associated with significant improvement in liver symptoms such as fatigue and pain over the liver, especially among those with higher ALT, HBV DNA, symptoms and HBeAg + status prior to treatment.


Assuntos
Antivirais , Hepatite B Crônica , Humanos , Masculino , Adulto , Feminino , Tenofovir/efeitos adversos , Antivirais/efeitos adversos , Antígenos E da Hepatite B , DNA Viral , Vírus da Hepatite B/genética , Resultado do Tratamento , Hepatite B Crônica/diagnóstico , Biomarcadores
3.
Biometrics ; 79(4): 3676-3689, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37129942

RESUMO

Q-learning has been one of the most commonly used methods for optimizing dynamic treatment regimes (DTRs) in multistage decision-making. Right-censored survival outcome poses a significant challenge to Q-Learning due to its reliance on parametric models for counterfactual estimation which are subject to misspecification and sensitive to missing covariates. In this paper, we propose an imputation-based Q-learning (IQ-learning) where flexible nonparametric or semiparametric models are employed to estimate optimal treatment rules for each stage and then weighted hot-deck multiple imputation (MI) and direct-draw MI are used to predict optimal potential survival times. Missing data are handled using inverse probability weighting and MI, and the nonrandom treatment assignment among the observed is accounted for using a propensity-score approach. We investigate the performance of IQ-learning via extensive simulations and show that it is more robust to model misspecification than existing Q-Learning methods, imputes only plausible potential survival times contrary to parametric models and provides more flexibility in terms of baseline hazard shape. Using IQ-learning, we developed an optimal DTR for leukemia treatment based on a randomized trial with observational follow-up that motivated this study.


Assuntos
Simulação por Computador , Pontuação de Propensão
4.
J Gastroenterol Hepatol ; 38(6): 989-998, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36890337

RESUMO

BACKGROUND AND AIM: Staining for hepatitis B viral antigens is often done in liver biopsies from patients with chronic hepatitis B, but its correlates with clinical phenotypes are not well described. METHODS: Biopsies were collected from a large cohort of adults and children with chronic hepatitis B viral infection through the Hepatitis B Research Network. Immunohistochemical staining of sections was done for hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) and then centrally read by the pathology committee. The degree of liver injury and pattern of staining were then correlated with clinical characteristics, including the clinical phenotype of hepatitis B. RESULTS: Biopsies from 467 subjects were studied, including 46 from children. Immunostaining for HBsAg was positive in 417 (90%) with scattered hepatocyte staining being the most common pattern. HBsAg staining correlated best with serum levels of HBsAg and hepatitis B viral DNA; the absence of HBsAg staining was often a prelude to loss of HBsAg from serum. HBcAg staining was positive in 225 (49%), and, while cytoplasmic staining was more frequent than nuclear staining, both nuclear and cytoplasmic positivity were often seen in the same specimen. Staining for HBcAg correlated with both level of viremia and liver injury. No biopsies from inactive carriers had stainable HBcAg, while 91% of the biopsies from those with hepatitis B e antigen-positive chronic hepatitis B stained positively for HBcAg. CONCLUSION: Immunostaining for hepatitis B viral antigens may yield helpful insights into liver disease pathogenesis but appears to add little to commonly used serological and biochemical blood tests.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Antígenos de Superfície da Hepatite B , Hepatite B Crônica/patologia , Antígenos do Núcleo do Vírus da Hepatite B , Fígado/patologia , Hepatite B/diagnóstico , Vírus da Hepatite B/genética , DNA Viral
5.
Ann Intern Med ; 176(4): 515-523, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36940444

RESUMO

BACKGROUND: Patients hospitalized with COVID-19 have an increased incidence of thromboembolism. The role of extended thromboprophylaxis after hospital discharge is unclear. OBJECTIVE: To determine whether anticoagulation is superior to placebo in reducing death and thromboembolic complications among patients discharged after COVID-19 hospitalization. DESIGN: Prospective, randomized, double-blind, placebo-controlled clinical trial. (ClinicalTrials.gov: NCT04650087). SETTING: Done during 2021 to 2022 among 127 U.S. hospitals. PARTICIPANTS: Adults aged 18 years or older hospitalized with COVID-19 for 48 hours or more and ready for discharge, excluding those with a requirement for, or contraindication to, anticoagulation. INTERVENTION: 2.5 mg of apixaban versus placebo twice daily for 30 days. MEASUREMENTS: The primary efficacy end point was a 30-day composite of death, arterial thromboembolism, and venous thromboembolism. The primary safety end points were 30-day major bleeding and clinically relevant nonmajor bleeding. RESULTS: Enrollment was terminated early, after 1217 participants were randomly assigned, because of a lower than anticipated event rate and a declining rate of COVID-19 hospitalizations. Median age was 54 years, 50.4% were women, 26.5% were Black, and 16.7% were Hispanic; 30.7% had a World Health Organization severity score of 5 or greater, and 11.0% had an International Medical Prevention Registry on Venous Thromboembolism risk prediction score of greater than 4. Incidence of the primary end point was 2.13% (95% CI, 1.14 to 3.62) in the apixaban group and 2.31% (CI, 1.27 to 3.84) in the placebo group. Major bleeding occurred in 2 (0.4%) and 1 (0.2%) and clinically relevant nonmajor bleeding occurred in 3 (0.6%) and 6 (1.1%) apixaban-treated and placebo-treated participants, respectively. By day 30, thirty-six (3.0%) participants were lost to follow-up, and 8.5% of apixaban and 11.9% of placebo participants permanently discontinued the study drug treatment. LIMITATIONS: The introduction of SARS-CoV-2 vaccines decreased the risk for hospitalization and death. Study enrollment spanned the peaks of the Delta and Omicron variants in the United States, which influenced illness severity. CONCLUSION: The incidence of death or thromboembolism was low in this cohort of patients discharged after hospitalization with COVID-19. Because of early enrollment termination, the results were imprecise and the study was inconclusive. PRIMARY FUNDING SOURCE: National Institutes of Health.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Hemorragia , Tromboembolia Venosa , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticoagulantes/efeitos adversos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Método Duplo-Cego , Hemorragia/induzido quimicamente , Hospitalização , Estudos Prospectivos , SARS-CoV-2 , Resultado do Tratamento , Tromboembolia Venosa/tratamento farmacológico
6.
Am J Gastroenterol ; 118(7): 1226-1236, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728214

RESUMO

INTRODUCTION: Withdrawal of nucleos(t)ide analog therapy is increasingly being evaluated in chronic hepatitis B infection as a strategy to induce hepatitis B surface antigen (HBsAg) loss. The Hepatitis B Research Network Immune-Active Trial evaluated treatment with tenofovir (TDF) for 4 years ± an initial 6 months of peginterferon-α (PegIFN) (NCT01369212) after which treatment was withdrawn. METHODS: Eligible participants (hepatitis B e antigen [HBeAg]-/anti-HBe+, hepatitis B virus [HBV] DNA <10 3 IU/mL, no cirrhosis) who discontinued TDF were followed for at least 1 year with optional follow-up thereafter. Retreatment was based on predefined criteria. RESULTS: Among 201 participants who received 4 years of treatment, 97 participants (45 TDF and 52 TDF + PegIFN arm, 79 Asian) discontinued TDF. HBsAg loss occurred in 5 participants, 2 within 25 weeks and 3 within 89-119 weeks postwithdrawal (cumulative rate 4.3% by 2 years). Alanine aminotransferase (ALT) flares (>5× upper limit of normal) after TDF withdrawal occurred in 36 (37.1%) participants and occurred more frequently and earlier in those HBeAg- compared with HBeAg+ at treatment initiation. ALT flares were associated with older age and higher HBV DNA pretreatment and at the visit before the flare. ALT flares were not significantly associated with HBsAg decline or loss but were associated with immune active disease at 1 year (70.6% vs 11.9%, P < 0.0001) and 2 years (66.7% vs 25.9%, P = 0.03) postwithdrawal. Treatment reinitiation was required in 13 (13.4%) participants, and 13 others remained in a sustained inactive carrier state by the end of the study follow-up. No criteria reliably predicted safe treatment withdrawal. DISCUSSION: Results from this trial do not support TDF withdrawal as a therapeutic strategy. HBsAg loss was infrequent within 2 years of stopping long-term TDF. If withdrawal is considered, HBV DNA should be carefully monitored with reinitiation of therapy if levels rise above 4 log 10 IU/mL to reduce the risk of ALT flares, as they were not associated with subsequent HBsAg decline or loss.


Assuntos
Hepatite B Crônica , Humanos , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , DNA Viral , Vírus da Hepatite B/genética , Nucleotídeos/uso terapêutico , Antivirais/uso terapêutico , Resultado do Tratamento
7.
PLoS One ; 18(1): e0279893, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36598904

RESUMO

Arsenic is a potent environmental toxicant and human carcinogen. Skin lesions are the most common manifestations of chronic exposure to arsenic. Advanced-stage skin lesions, particularly hyperkeratosis have been recognized as precancerous diseases. However, the underlying mechanism of arsenic-induced skin lesions remains unknown. Periostin, a matricellular protein, is implicated in the pathogenesis of many forms of skin lesions. The objective of this study was to examine whether periostin is associated with arsenic-induced skin lesions. A total of 442 individuals from low- (n = 123) and high-arsenic exposure areas (n = 319) in rural Bangladesh were evaluated for the presence of arsenic-induced skin lesions (Yes/No). Participants with skin lesions were further categorized into two groups: early-stage skin lesions (melanosis and keratosis) and advanced-stage skin lesions (hyperkeratosis). Drinking water, hair, and nail arsenic concentrations were considered as the participants' exposure levels. The higher levels of arsenic and serum periostin were significantly associated with skin lesions. Causal mediation analysis revealed the significant effect of arsenic on skin lesions through the mediator, periostin, suggesting that periostin contributes to the development of skin lesions. When skin lesion was used as a three-category outcome (none, early-stage, and advanced-stage skin lesions), higher serum periostin levels were significantly associated with both early-stage and advanced-stage skin lesions. Median (IQR) periostin levels were progressively increased with the increasing severity of skin lesions. Furthermore, there were general trends in increasing serum type 2 cytokines (IL-4, IL-5, IL-13, and eotaxin) and immunoglobulin E (IgE) levels with the progression of the disease. The median (IQR) of IL-4, IL-5, IL-13, eotaxin, and IgE levels were significantly higher in the early-and advanced-stage skin lesions compared to the group of participants without skin lesions. The results of this study suggest that periostin is implicated in the pathogenesis and progression of arsenic-induced skin lesions through the dysregulation of type 2 immune response.


Assuntos
Arsênio , Ceratose Actínica , Dermatopatias , Humanos , Arsênio/toxicidade , Arsênio/análise , Interleucina-13 , Interleucina-4 , Interleucina-5 , Exposição Ambiental , Abastecimento de Água , Dermatopatias/induzido quimicamente , Imunoglobulina E/efeitos adversos
8.
Lifetime Data Anal ; 29(1): 234-252, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36593432

RESUMO

Quantile residual lifetime (QRL) is of significant interest in many clinical studies as an easily interpretable quantity compared to other summary measures of survival distributions. In cancer or other chronic diseases, treatments are often compared based on the distributions or quantiles of the residual lifetime. Thus a common problem of interest is to test the equality of the QRL between two populations. In this paper, we propose two classes of tests to compare two QRLs; one class is based on the difference between two estimated QRLs, and the other is based on the estimating function of the QRL, where the estimated QRL from one sample is plugged into the QRL-estimating-function of the other sample. We outline the asymptotic properties of these test statistics. Simulation studies demonstrate that the proposed tests produced Type I errors closer to the nominal level and are superior to some existing tests based on both Type I error and power. Our proposed test statistics are also computationally less intensive and more straightforward compared to tests based on the confidence intervals. We applied the proposed methods to a randomized multicenter phase III trial for breast cancer patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Análise de Sobrevida , Simulação por Computador
9.
Am J Gastroenterol ; 118(7): 1214-1225, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36599136

RESUMO

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.


Assuntos
Hepatite B Crônica , Humanos , Adulto , Tenofovir/uso terapêutico , Antivirais , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Resultado do Tratamento , Vírus da Hepatite B/genética , Polietilenoglicóis/uso terapêutico , DNA Viral
10.
Hepatology ; 77(2): 594-605, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35770681

RESUMO

BACKGROUND AND AIMS: Liver injury may persist in patients with HBV receiving antiviral therapy who have ongoing transcription and translation. We sought to assess ongoing HBV transcription by serum HBV RNA, translation by serum hepatitis B core related antigen (HBcrAg), and their associations with hepatic HBsAg and HBcAg staining in patients coinfected with HBV and HIV. METHODS: This is a cross-sectional study of 110 adults coinfected with HBV and HIV who underwent clinical assessment and liver biopsy. Immunohistochemistry (IHC) was performed for HBsAg and HBcAg. Viral biomarkers included quantitative HBsAg, HBV RNA, and HBcrAg. RESULTS: Participants' median age was 49 years (male, 93%; Black, 51%; HBeAg+, 65%), with suppressed HBV DNA (79%) and undetectable HIV RNA (77%) on dually active antiretroviral therapy. Overall, HBV RNA and HBcrAg were quantifiable in 81% and 83%, respectively (96% and 100% in HBeAg+, respectively). HBcAg staining was detected in 60% and HBsAg in 79%. Higher HBV RNA was associated with higher HBcAg and HBsAg IHC grades (both p < 0.0001). The HBsAg membranous staining pattern was significantly associated with higher HBV-RNA and HBcrAg levels. CONCLUSION: HBcAg and HBsAg IHC staining persisted despite viral suppression, and IHC grades and staining patterns correlated with markers of transcription (HBV RNA) and translation (HBcrAg). These data indicate that apparent HBV suppression is associated with residual transcription and translation that could contribute to liver pathology. Additional antiviral strategies directed to HBV protein expression may be useful to ameliorate liver injury.


Assuntos
Antirretrovirais , Coinfecção , Infecções por HIV , Vírus da Hepatite B , Hepatite B Crônica , Transcrição Viral , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores , Coinfecção/tratamento farmacológico , Coinfecção/imunologia , Coinfecção/fisiopatologia , Coinfecção/virologia , Estudos Transversais , DNA Viral , Antígenos do Núcleo do Vírus da Hepatite B , Antígenos E da Hepatite B , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/imunologia , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , RNA , Transcrição Viral/efeitos dos fármacos , Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , Biossíntese de Proteínas/efeitos dos fármacos
11.
Clin Gastroenterol Hepatol ; 21(7): 1881-1892.e4, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36116752

RESUMO

BACKGROUND & AIMS: Acute hepatitis B virus (aHBV) is thought to be self-limited with clearance of hepatitis B surface antigen (HBsAg) within 6 months. There are limited reports of the presenting features and outcomes of adults with symptomatic aHBV in the United States. METHODS: Demographics, clinical features, and 12-month outcomes of patients with adjudicated aHBV were captured prospectively and compared with a contemporaneous cohort of chronic HBV (cHBV) patients enrolled in the Hepatitis B Research Network. RESULTS: Between 2011 and 2018, 60 adjudicated patients with aHBV were compared with 1534 cHBV untreated controls. Although similar in age, other features were dissimilar: aHBV patients were more often male (72% vs 51%), single (72% vs 30%), and non-Hispanic whites or blacks (75% vs 24%). They also were frequently genotype A2 (65% vs 9%), having different risk factors: sexual exposure (75% vs 16%) or injection drug use (10% vs 2%), compared with the cHBV controls. In addition to higher serum aminotransferase and bilirubin levels, acute patients had higher HBV DNA levels (4.8 vs 3.6 log10 IU/mL), whereas quantitative hepatitis B e antigen (HBeAg) levels were lower (1.4 vs 3.0 log10 IU/mL), despite higher rates of HBeAg (73% vs 25%). The median time to HBsAg clearance was 27 weeks and to anti-HBs appearance, 41 weeks. CONCLUSIONS: In the current era, caucasian men infected with genotype A2 as a result of sexual exposure or injection drug use were the predominant group in aHBV, suggesting a potential strategy for adult vaccination in North America. Strikingly, only an estimated 36% of subjects cleared HBsAg by month 6; the definition of resolution in acute hepatitis B may need to be modified. ClinicalTirals.gov number NCT01263587.


Assuntos
Hepatite B Crônica , Hepatite B , Adulto , Humanos , Masculino , Estados Unidos/epidemiologia , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Hepatite B Crônica/tratamento farmacológico , Hepatite B/epidemiologia , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/genética
12.
Biometrics ; 79(1): 368-380, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34571583

RESUMO

A sequential multiple assignment randomized trial (SMART) facilitates the comparison of multiple adaptive treatment strategies (ATSs) simultaneously. Previous studies have established a framework to test the homogeneity of multiple ATSs by a global Wald test through inverse probability weighting. SMARTs are generally lengthier than classical clinical trials due to the sequential nature of treatment randomization in multiple stages. Thus, it would be beneficial to add interim analyses allowing for an early stop if overwhelming efficacy is observed. We introduce group sequential methods to SMARTs to facilitate interim monitoring based on the multivariate chi-square distribution. Simulation studies demonstrate that the proposed interim monitoring in SMART (IM-SMART) maintains the desired type I error and power with reduced expected sample size compared to the classical SMART. Finally, we illustrate our method by reanalyzing a SMART assessing the effects of cognitive behavioral and physical therapies in patients with knee osteoarthritis and comorbid subsyndromal depressive symptoms.


Assuntos
Projetos de Pesquisa , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , Simulação por Computador , Distribuição de Qui-Quadrado
13.
medRxiv ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38168372

RESUMO

Alcohol-related hepatitis (AH) is plagued with high mortality and difficulty in identifying at-risk patients. The extracellular matrix undergoes significant remodeling during inflammatory liver injury that can be detected in biological fluids and potentially used for mortality prediction. EDTA plasma samples were collected from AH patients (n= 62); Model for End-Stage Liver Disease (MELD) score defined AH severity as moderate (12-20; n=28) and severe (>20; n=34). The peptidome data was collected by high resolution, high mass accuracy UPLC-MS. Univariate and multivariate analyses identified differentially abundant peptides, which were used for Gene Ontology, parent protein matrisomal composition and protease involvement. Machine learning methods were used on patient-specific peptidome and clinical data to develop mortality predictors. Analysis of plasma peptides from AH patients and healthy controls identified over 1,600 significant peptide features corresponding to 130 proteins. These were enriched for ECM fragments in AH samples, likely related to turnover of hepatic-derived proteins. Analysis of moderate versus severe AH peptidomes showed a shift in abundance of peptides from collagen 1A1 and fibrinogen A proteins. The dominant proteases for the AH peptidome spectrum appear to be CAPN1 and MMP12. Increase in hepatic expression of these proteases was orthogonally-validated in RNA-seq data of livers from AH patients. Causal graphical modeling identified four peptides directly linked to 90-day mortality in >90% of the learned graphs. These peptides improved the accuracy of mortality prediction over MELD score and were used to create a clinically applicable mortality prediction assay. A signature based on plasma peptidome is a novel, non-invasive method for prognosis stratification in AH patients. Our results could also lead to new mechanistic and/or surrogate biomarkers to identify new AH mechanisms. Lay summary: We used degraded proteins found the blood of alcohol-related hepatitis patients to identify new potential mechanisms of injury and to predict 90 day mortality.

14.
J Stat Theory Appl ; 21(3): 79-105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35996625

RESUMO

Number of children ever born to women of reproductive age forms a core component of fertility and is vital to the population dynamics in any country. Using Bangladesh Multiple Indicator Cluster Survey 2019 data, we fitted a novel weighted Bayesian Poisson regression model to identify multi-level individual, household, regional and societal factors of the number of children ever born among married women of reproductive age in Bangladesh. We explored the robustness of our results using multiple prior distributions, and presented the Metropolis algorithm for posterior realizations. The method is compared with regular Bayesian Poisson regression model using a Weighted Bayesian Information Criterion. Factors identified emphasize the need to revisit and strengthen the existing fertility-reduction programs and policies in Bangladesh. Supplementary Information: The online version contains supplementary material available at 10.1007/s44199-022-00044-2.

15.
Prev Med ; 161: 107155, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35817162

RESUMO

Mortality due to opioid misuse and overdose has increased substantially in the United States over the past two decades. The study objective was to describe the causes of death among persons with opioid-related hospitalizations and examine survival by Hepatitis C virus (HCV) or HIV. Opioid-related hospitalization records in Pennsylvania from 2000 to 2010 were linked to death registry files to assess cause of death, and survival from first hospital discharge date to death date, or December 31, 2010. Accelerated failure time models were used to compare survival between persons with and without HCV or HIV diagnoses. Among the 136,416 individuals with an opioid-related hospitalization, 13.0% died over a median of 56 months of follow-up; the most common causes of death were circulatory diseases (26.4%) and drug overdose (23.5%). There were 27,122 (19.9%) and 3662 (2.7%) persons who had an HCV and HIV diagnosis, respectively. Among patients aged ≥20 years, those with HCV had shorter survival time compared to those without HCV, with discrepancies more pronounced at older ages. Patients with HIV also had shorter survival time (time ratio: 0.29 [95% CI: 0.26, 0.34]) compared to without HIV. These findings show that in a cohort of patients with opioid-related hospitalizations, those with HCV or HIV diagnoses have shorter survival. This has public health implications, providing further evidence that medical providers should educate patients who use opioids about the risks of HCV and HIV infection and focus prevention and treatment to decrease mortality among patients hospitalized for opioid use.


Assuntos
Overdose de Drogas , Infecções por HIV , Hepatite C , Transtornos Relacionados ao Uso de Opioides , Analgésicos Opioides/efeitos adversos , Infecções por HIV/tratamento farmacológico , Hepacivirus , Hepatite C/tratamento farmacológico , Hospitalização , Humanos , Estados Unidos
16.
Surg Obes Relat Dis ; 18(7): 902-910, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35589527

RESUMO

BACKGROUND: Long-term change in CRP is not well characterized in the context of RYGB. OBJECTIVE: To report C-reactive protein (CRP) after Roux-en-Y gastric bypass surgery (RYGB). SETTING: Between 2006 and 2009 1770 adults enrolled in a prospective cohort study underwent Roux-en-Y gastric bypass (RYGB) at 1 of 10 U.S. hospitals. METHODS: Research assessments were conducted before surgery and annually postoperatively for up to 7 years. This study included those with high-sensitivity CRP assessed before surgery and 1 or more follow-up assessments (n = 1180). RESULTS: Before surgery, participants' median age was 46 years, and the median body mass index (BMI) was 46 kg/m2; 80% were female. Before surgery, mean (95% confidence interval [CI]) CRP was the highest of all time points (1.01 [.95-1.08] mg/L); it then decreased to a nadir of .18 (.15-.22) mg/L at 2 years postoperatively (P < .001). CRP was higher at 7 years (.26 [.22, .29] mg/L) than at 2 years postoperatively (P < .001) but remained lower at 7 years than preoperatively (P < .001). Additionally, only 3.2% (95% CI: 1.6%-4.8%) of participants had elevated CRP (>1 mg/dL) 7 years postoperatively versus 32.9% (95% CI: 30.2%-35.3%) preoperatively (P < .001). Several preoperative factors were associated with following a less favorable CRP trajectory over time, including higher preoperative CRP level, higher BMI, current smoking, and diabetes. CONCLUSION: The vast majority of adults who underwent RYGB experienced a sustained improvement in CRP throughout 7 years of follow-up with nonelevated values. However, those with higher preoperative CRP and BMI levels and diabetes and who smoke may benefit from additional testing and monitoring to ensure nonelevated inflammation after surgery.


Assuntos
Derivação Gástrica , Obesidade Mórbida , Adulto , Índice de Massa Corporal , Proteína C-Reativa , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso
17.
Chemosphere ; 298: 134277, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35278445

RESUMO

Chronic exposure to arsenic via drinking water is a serious public health issue in many countries. Arsenic causes not only cancers but also non-malignant diseases, including asthma. We have previously reported that arsenic exposure increases the risk of Th2-mediated allergic asthma. The serum level of periostin, an extracellular matrix protein activated by Th2 cytokines, is recognized as a biomarker for Th2-mediated eosinophilic asthma and contributes to enhanced airway inflammation and remodeling. However, the role of periostin in arsenic-related asthma is unknown. Therefore, this study was designed to explore the associations of serum periostin levels with arsenic exposure and the features of asthma in 442 individuals in Bangladesh who participated in our previous study. Exposure levels of the participants were determined by measuring the arsenic concentrations in drinking water, hair, and nails through inductively coupled plasma mass spectroscopy. Periostin levels in serum were assessed by immunoassay. In this study, we found that serum periostin levels of the participants were increased with increasing exposure to arsenic. Notably, even the participants with 10.1-50 µg/L arsenic in drinking water had significantly higher levels of periostin than participants with <10 µg/L of water arsenic. Elevated serum periostin levels were positively associated with serum levels of Th2 mediators, such as interleukin (IL)-4, IL-5, IL-13, and eotaxin. Each log increase in periostin levels was associated with approximately eight- and three-fold increases in the odds ratios (ORs) for reversible airway obstruction (RAO) and asthma symptoms, respectively. Additionally, causal mediation analyses revealed that arsenic exposure metrics had both direct and indirect (periostin-mediated) effects on the risk of RAO and asthma symptoms. Thus, the results suggested that periostin may be involved in the arsenic-related pathogenesis of Th2-mediated asthma. The elevated serum periostin levels may predict the greater risk of asthma among the people living in arsenic-endemic areas.


Assuntos
Intoxicação por Arsênico , Arsênio , Asma , Água Potável , Arsênio/análise , Asma/induzido quimicamente , Asma/epidemiologia , Biomarcadores/análise , Água Potável/análise , Humanos , Unhas/química
18.
Biostatistics ; 23(4): 1182-1199, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34052847

RESUMO

Sequential multiple assignment randomized trials (SMARTs) are systematic and efficient media for comparing dynamic treatment regimes (DTRs), where each patient is involved in multiple stages of treatment with the randomization at each stage depending on the patient's previous treatment history and interim outcomes. Generally, patients enrolled in SMARTs are randomized equally to ethically acceptable treatment options regardless of how effective those treatments were during the previous stages, which results in some undesirable consequences in practice, such as low recruitment, less retention, and lower treatment adherence. In this article, we propose a response-adaptive SMART (RA-SMART) design where the allocation probabilities are imbalanced in favor of more promising treatments based on the accumulated information on treatment efficacy from previous patients and stages. The operating characteristics of the RA-SMART design relative to SMART design, including the consistency and efficiency of estimated response rate under each DTR, the power of identifying the optimal DTR, and the number of patients treated with the optimal and the worst DTRs, are assessed through extensive simulation studies. Some practical suggestions are discussed in the conclusion.


Assuntos
Projetos de Pesquisa , Simulação por Computador , Humanos , Distribuição Aleatória , Resultado do Tratamento
19.
Hepatology ; 75(3): 709-723, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34743343

RESUMO

BACKGROUND AND AIMS: Achieving HBsAg loss is an important landmark in the natural history of chronic hepatitis B (CHB). A more personalized approach to prediction of HBsAg loss is relevant in counseling patients. This study sought to develop and validate a prediction model for HBsAg loss based on quantitative HBsAg levels (qHBsAg) and other baseline characteristics. METHODS: The Hepatitis B Research Network (HBRN) is a prospective cohort including 1240 untreated HBeAg-negative patients (1150 adults, 90 children) with median follow-up of 5.5 years. Incidence rates of HBsAg loss and hepatitis B surface antibody (anti-HBs) acquisition were determined, and a predictor score of HBsAg loss using readily available variables was developed and externally validated. RESULTS: Crude incidence rates of HBsAg loss and anti-HBs acquisition were 1.6 and 1.1 per 100 person-years (PY); 67 achieved sustained HBsAg loss for an incidence rate of 1.2 per 100 PY. Increased HBsAg loss was significantly associated with older age, non-Asian race, HBV phenotype (inactive CHB vs. others), HBV genotype A, lower HBV-DNA levels, and lower and greater change in qHBsAg. The HBRN-SQuARe (sex,∆quantHBsAg, age, race) score predicted HBsAg loss over time with area under the receiver operating characteristic curve (AUROC) (95% CIs) at 1 and 3 years of 0.99 (95% CI: 0.987-1.00) and 0.95 (95% CI 0.91-1.00), respectively. In validation in another cohort of 1253 HBeAg-negative patients with median follow-up of 3.1 years, HBRN SQuARe predicted HBsAg loss at 1 and 3 years with AUROC values of 0.99 (0.98-1.00) and 0.88 (0.77-0.99), respectively. CONCLUSION: HBsAg loss in predominantly untreated patients with HBeAg-negative CHB can be accurately predicted over a 3-year horizon using a simple validated score (HBRN SQuARe). This prognostication tool can be used to support patient care and counseling.


Assuntos
Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Adulto , Fatores Etários , Criança , Etnicidade/estatística & dados numéricos , Feminino , Seguimentos , Anticorpos Anti-Hepatite B/análise , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/análise , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/imunologia , Humanos , Incidência , Masculino , Valor Preditivo dos Testes , Prognóstico , Testes Sorológicos/métodos , Testes Sorológicos/estatística & dados numéricos , Resposta Viral Sustentada
20.
Lifetime Data Anal ; 28(1): 1-22, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807357

RESUMO

Many medical conditions are marked by a sequence of events in association with continuous changes in biomarkers. Few works have evaluated the overall accuracy of a biomarker in predicting disease progression. We thus extend the concept of receiver operating characteristic (ROC) surface and the volume under the surface (VUS) from multi-category outcomes to ordinal competing-risk outcomes that are also subject to noninformative censoring. Two VUS estimators are considered. One is based on the definition of the ROC surface and obtained by integrating the estimated ROC surface. The other is an inverse probability weighted U estimator that is built upon the equivalence of the VUS to the concordance probability between the marker and sequential outcomes. Both estimators have nice asymptotic results that can be derived using counting process techniques and U-statistics theory. We illustrate their good practical performances through simulations and applications to two studies of cognition and a transplant dataset.


Assuntos
Curva ROC , Biomarcadores , Humanos , Probabilidade , Prognóstico
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