In clinical trials and survival analysis, participants may be excluded from the study due to withdrawal, which is often referred to as lost-to-follow-up (LTF). It is natural to argue that a disease ...would be censored due to death; however, when an LTF is present it is not guaranteed that the disease has been censored. This makes it important to consider both cases; the disease is censored or not censored. We also note that the illness process can be censored by LTF. We will consider a multi-state model in which LTF is not regarded as censoring but as a non-fatal event.
We propose a multi-state model for analyzing semi-competing risks data with interval-censored or missing intermediate events. More precisely, we employ the additive and multiplicative hazards model with log-normal frailty and construct the conditional likelihood to estimate the transition intensities among states in the multi-state model. Marginalization of the full likelihood is accomplished using adaptive importance sampling, and the optimal solution of the regression parameters is achieved through the iterative quasi-Newton algorithm.
Simulation is performed to investigate the finite-sample performance of the proposed estimation method in terms of the relative bias and coverage probability of the regression parameters. The proposed estimators turned out to be robust to misspecifications of the frailty distribution. PAQUID data have been analyzed and yielded somewhat prominent results.
We propose a multi-state model for semi-competing risks data for which there exists information on fatal events, but information on non-fatal events may not be available due to lost to follow-up. Simulation results show that the coverage probabilities of the regression parameters are close to a nominal level of 0.95 in most cases. Regarding the analysis of real data, the risk of transition from a healthy state to dementia is higher for women; however, the risk of death after being diagnosed with dementia is higher for men.
The current system granting liver transplant candidates with hepatocellular carcinoma (HCC) additional Model for End‐Stage Liver Disease (MELD) points is controversial due to geographic disparity and ...uncertainty regarding optimal prioritization of candidates. The current national policy assigns a MELD exception score of 22 immediately upon listing of eligible patients with HCC. The aim of this study was to evaluate the potential effects of delays in granting these exception points on transplant rates for HCC and non‐HCC patients. We used Scientific Registry of Transplant Recipients data and liver simulated allocation modeling software and modeled (1) a 3‐month delay before granting a MELD exception score of 25, (2) a 6‐month delay before granting a score of 28, and (3) a 9‐month delay before granting a score of 29. Of all candidates waitlisted between January 1 and December 31, 2010 (n = 28,053), 2773 (9.9%) had an HCC MELD exception. For HCC candidates, transplant rates would be 108.7, 65.0, 44.2, and 33.6 per 100 person‐years for the current policy and for 3‐, 6‐, and 9‐month delays, respectively. Corresponding rates would be 30.1, 32.5, 33.9, and 34.8 for non‐HCC candidates. Conclusion: A delay of 6‐9 months would eliminate the geographic variability in the discrepancy between HCC and non‐HCC transplant rates under current policy and may allow for more equal access to transplant for all candidates. (Hepatology 2015;61:1643–1650)
Background & Aims The historical prevalence and long-term outcome of undiagnosed celiac disease (CD) are unknown. We investigated the long-term outcome of undiagnosed CD and whether the prevalence of ...undiagnosed CD has changed during the past 50 years. Methods This study included 9133 healthy young adults at Warren Air Force Base (sera were collected between 1948 and 1954) and 12,768 gender-matched subjects from 2 recent cohorts from Olmsted County, Minnesota, with either similar years of birth ( n = 5558) or age at sampling ( n = 7210) to that of the Air Force cohort. Sera were tested for tissue transglutaminase and, if abnormal, for endomysial antibodies. Survival was measured during a follow-up period of 45 years in the Air Force cohort. The prevalence of undiagnosed CD between the Air Force cohort and recent cohorts was compared. Results Of 9133 persons from the Air Force cohort, 14 (0.2%) had undiagnosed CD. In this cohort, during 45 years of follow-up, all-cause mortality was greater in persons with undiagnosed CD than among those who were seronegative (hazard ratio = 3.9; 95% confidence interval, 2.0–7.5; P < .001). Undiagnosed CD was found in 68 (0.9%) persons with similar age at sampling and 46 (0.8%) persons with similar years of birth. The rate of undiagnosed CD was 4.5-fold and 4-fold greater in the recent cohorts, respectively, than in the Air Force cohort (both P ≤ .0001). Conclusions During 45 years of follow-up, undiagnosed CD was associated with a nearly 4-fold increased risk of death. The prevalence of undiagnosed CD seems to have increased dramatically in the United States during the past 50 years.
Ovarian cancer has a clear predilection for metastasis to the omentum, but the underlying mechanisms involved in ovarian cancer spread are not well understood. Here, we used a parabiosis model that ...demonstrates preferential hematogenous metastasis of ovarian cancer to the omentum. Our studies revealed that the ErbB3-neuregulin 1 (NRG1) axis is a dominant pathway responsible for hematogenous omental metastasis. Elevated levels of ErbB3 in ovarian cancer cells and NRG1 in the omentum allowed for tumor cell localization and growth in the omentum. Depletion of ErbB3 in ovarian cancer impaired omental metastasis. Our results highlight hematogenous metastasis as an important mode of ovarian cancer metastasis. These findings have implications for designing alternative strategies aimed at preventing and treating ovarian cancer metastasis.
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•Epithelial ovarian cancer metastasizes to the omentum hematogenously•Elevated levels of NRG1 in the omentum promote the homing of ovarian cancer cells•ErbB3-expressing CTCs foster hematogenous metastases•ErbB3 knockdown inhibits ovarian cancer metastasis
Using a parabiosis model, Pradeep et al. find that ovarian cancer cells metastasize to the omentum most often via the blood. They show that hematogenous metastasis is dependent on an activated neuregulin 1-ErbB3 pathway, which supports localization to and growth in the omentum, suggesting ErbB3 as a therapeutic target.
The study aims to determine whether type and density of tumour-infiltrating lymphocytes (TILs) can predict the clinical course in gastric cancer. Gastric carcinomas (n=220) were immunostained for ...CD3, CD8, CD20, and CD45RO and evaluated for clinicopathologic characteristics. Number of TILs that immunostained positively for each marker were counted using NIH ImageJ software. Tumours were grouped into low- and high-density groups for each marker (CD3, CD8, CD45RO). The densities of CD3(+), CD8(+), and CD45RO(+) TILs were found to be independent predictors of lymph node metastasis by multivariate analysis with odds ratios (95% CI) of 0.425 (0.204-0.885), 0.325 (0.150-0.707), and 0.402 (0.190-0.850), respectively. Kaplan-Meier survival analysis revealed that patients in the high-density groups for CD3, CD8, and C45RO had a significantly longer survival time than the patients in the corresponding low-density groups, respectively. In multivariate survival analysis, the densities of CD3(+), CD8(+), and CD45RO(+) TILs remained independent prognostic factors with hazard ratios (95% CI) of 0.549 (0.317-0.951), 0.574 (0.347-0.949), and 0.507 (0.298-0.862), respectively. In conclusion, density of TILs was found to be independently predictive of regional lymph node metastasis and patient survival in gastric cancer.
AbstractObjectiveThe AGO-OVAR16 study was designed to test the efficacy, safety, and tolerability of pazopanib maintenance after first-line chemotherapy in patients with newly diagnosed advanced ...ovarian cancer (AOC). MethodsNine hundred and forty patients with histologically confirmed AOC, International Federation of Gynecology and Obstetrics (FIGO) stage II–IV, were randomized in a 1:1 ratio to receive either 800 mg pazopanib once daily or placebo for up to 24 months, unless there was disease progression, toxicity, withdrawal of consent, or death. The primary endpoint (investigator-assessed progression-free survival PFS) was met and previously reported. The results of final analyses of overall survival (OS) are reported here. ResultsA third OS interim analysis showed futility and led to study closure and a final OS analysis after last patient last visit. At the time of the final OS analysis, 494 (89.7% of the planned 551) events had occurred. No difference was observed in OS between pazopanib and placebo. The hazard ratio (HR) was 0.960 (95% confidence interval CI: 0.805–1.145), and the median OS from randomization was 59.1 months in pazopanib and 64.0 months in placebo arms. For the East Asian patients, similar to the first three interim OS analyses, a numerical negative trend was observed favoring placebo (HR, 1.332; 95% CI: 0.863–2.054). Exploratory analyses showed a trend for a longer time to first subsequent anti-cancer therapy or death with pazopanib over placebo (HR, 0.829; 95% CI: 0.713–0.965), with a median estimate of 19.0 and 14.5 months, respectively. No new safety signals were observed. ConclusionAlthough pazopanib prolonged PFS, this was not associated with improvement in median OS. Clinical trial information.ClinicalTrials.gov: NCT00866697.
Adaptation requires genetic variation, but founder populations are generally genetically depleted. Here we sequence two populations of an inbred ant that diverge in phenotype to determine how ...variability is generated. Cardiocondyla obscurior has the smallest of the sequenced ant genomes and its structure suggests a fundamental role of transposable elements (TEs) in adaptive evolution. Accumulations of TEs (TE islands) comprising 7.18% of the genome evolve faster than other regions with regard to single-nucleotide variants, gene/exon duplications and deletions and gene homology. A non-random distribution of gene families, larvae/adult specific gene expression and signs of differential methylation in TE islands indicate intragenomic differences in regulation, evolutionary rates and coalescent effective population size. Our study reveals a tripartite interplay between TEs, life history and adaptation in an invasive species.
Objectives
Immune reconstitution inflammatory syndrome (IRIS) is a major concern when starting antiretroviral therapy (ART) in patients with advanced HIV infection. The aim of this study was to ...determine the incidence and risk factors of IRIS in HIV‐infected Koreans initiating ART, and whether integrase strand transfer inhibitor (INSTI) treatment increases the risk of IRIS.
Methods
This retrospective analysis included adults living with HIV, seen at four university‐affiliated hospitals in South Korea, who were naïve to ART and had a CD4 T‐cell count < 200 cells/μL between January 2004 and May 2019. IRIS was determined through a medical record review within 6 months of ART initiation. Propensity score‐matched case–control study between the non‐INSTI and INSTI groups was performed.
Results
The study included 501 patients; 192 were assigned to the INSTI group, who started ART based on INSTIs as the initial treatment. There were opportunistic infections (OIs) in 253 (50.5%) cases before ART initiation. The three most common OIs were Pneumocystis jirovecii pneumonia, candidiasis and tuberculosis (TB). We identified 47 cases of IRIS; TB‐IRIS was the most common type. The incidence of IRIS within 6 months of ART initiation was 9.4%, and there were no significant differences in baseline characteristics and incidence of IRIS between the matched groups. The risk factors for IRIS were pre‐ART CD4 T‐cell count (< 30 cells/μL), higher pre‐ART viral load (≥ 75 000 copies/mL), and TB‐OI.
Conclusions
The incidence of IRIS was 9.4% in Korean HIV patients. The INSTI regimen was not related to IRIS occurrence.
Although previous consensus recommendations have helped define patients who would benefit from simultaneous liver–kidney transplantation (SLK), there is a current need to reassess published ...guidelines for SLK because of continuing increase in proportion of liver transplant candidates with renal dysfunction and ongoing donor organ shortage. The purpose of this consensus meeting was to critically evaluate published and registry data regarding patient and renal outcomes following liver transplantation alone or SLK in liver transplant recipients with renal dysfunction. Modifications to the current guidelines for SLK and a research agenda were proposed.
The authors report the findings of a summit meeting on simultaneous liver–kidney transplantation, present modifications to the current guidelines and propose directions for future research. See editorial by Feng and Trotter on page 2869.
Previous studies have implicated the relationship between environmental phthalate exposure and attention deficit hyperactivity disorder (ADHD) symptoms of childhood, but no studies have been ...conducted in children who have a confirmed diagnosis of ADHD obtained through meticulous diagnostic testing. We aimed to determine whether phthalate metabolites in urine would be higher in children with ADHD than in those without ADHD and would correlate with symptom severity and cortical thickness in ADHD children.
A cross-sectional examination of urine phthalate metabolite concentrations was performed; scores for ADHD symptoms, externalizing problems, and continuous performance tests were obtained from 180 children with ADHD, and brain-imaging data were obtained from 115 participants. For the control group, children without ADHD (N = 438) were recruited. Correlations between phthalate metabolite concentrations and clinical measures and brain cortical thickness were investigated.
Concentrations of phthalate metabolites, particularly the di(2-ethylhexyl) phthalate (DEHP) metabolite, were significantly higher in boys with ADHD than in boys without ADHD. Concentrations of the di-n-butyl phthalate (DBP) metabolite were significantly higher in the combined or hyperactive-impulsive subtypes compared to the inattentive subtype, and the metabolite was positively correlated with the severity of externalizing symptoms. Concentrations of the DEHP metabolite were negatively correlated with cortical thickness in the right middle and superior temporal gyri.
The results of this study suggest an association between phthalate concentrations and both the diagnosis and symptom severity of ADHD. Imaging findings suggest a negative impact of phthalates on regional cortical maturation in children with ADHD.
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