Clinical states of cirrhosis and competing risks D'Amico, Gennaro; Morabito, Alberto; D'Amico, Mario ...
Journal of hepatology,
March 2018, 2018-03-00, 20180301, Letnik:
68, Številka:
3
Journal Article
Recenzirano
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The clinical course of cirrhosis is mostly determined by the progressive increase of portal hypertension, hyperdynamic circulation, bacterial translocation and activation of systemic inflammation. ...Different disease states, encompassing compensated and decompensated cirrhosis and a late decompensated state, are related to the progression of these mechanisms and may be recognised by haemodynamic or clinical characteristics. While these disease states do not follow a predictable sequence, they correspond to varying mortality risk. Acute-on-chronic liver failure may occur either in decompensated or in compensated cirrhosis and is always associated with a high short-term mortality. The increasing severity of these disease states prompted the concept of clinical states of cirrhosis. A multistate approach has been considered to describe the clinical course of the disease. Such an approach requires the assessment of the probabilities of different outcomes in each state, which compete with each other to occur first and mark the transition towards a different state. This requires the use of competing risks analysis, since the traditional Kaplan-Meier analysis should only be used in two-state settings. Accounting for competing risks also has implications for prognosis and treatment efficacy research. The aim of this review is to summarise relevant clinical states and to show examples of competing risks analysis in multistate models of cirrhosis.
Ex-vivo gene therapy (GT) with hematopoietic stem and progenitor cells (HSPCs) engineered with integrating vectors is a promising treatment for monogenic diseases, but lack of centralized databases ...is hampering an overall outcomes assessment. Here we aim to provide a comprehensive assessment of the short and long term safety of HSPC-GT from trials using different vector platforms. We review systematically the literature on HSPC-GT to describe survival, genotoxicity and engraftment of gene corrected cells. From 1995 to 2020, 55 trials for 14 diseases met inclusion criteria and 406 patients with primary immunodeficiencies (55.2%), metabolic diseases (17.0%), haemoglobinopathies (24.4%) and bone marrow failures (3.4%) were treated with gammaretroviral vector (γRV) (29.1%), self-inactivating γRV (2.2%) or lentiviral vectors (LV) (68.7%). The pooled overall incidence rate of death is 0.9 per 100 person-years of observation (PYO) (95% CI = 0.37-2.17). There are 21 genotoxic events out of 1504.02 PYO, which occurred in γRV trials (0.99 events per 100 PYO, 95% CI = 0.18-5.43) for primary immunodeficiencies. Pooled rate of engraftment is 86.7% (95% CI = 67.1-95.5%) for γRV and 98.7% (95% CI = 94.5-99.7%) for LV HSPC-GT (p = 0.005). Our analyses show stable reconstitution of haematopoiesis in most recipients with superior engraftment and safer profile in patients receiving LV-transduced HSPCs.
We investigated the long-term outcome of gene therapy for severe combined immunodeficiency (SCID) due to the lack of adenosine deaminase (ADA), a fatal disorder of purine metabolism and ...immunodeficiency.
We infused autologous CD34+ bone marrow cells transduced with a retroviral vector containing the ADA gene into 10 children with SCID due to ADA deficiency who lacked an HLA-identical sibling donor, after nonmyeloablative conditioning with busulfan. Enzyme-replacement therapy was not given after infusion of the cells.
All patients are alive after a median follow-up of 4.0 years (range, 1.8 to 8.0). Transduced hematopoietic stem cells have stably engrafted and differentiated into myeloid cells containing ADA (mean range at 1 year in bone marrow lineages, 3.5 to 8.9%) and lymphoid cells (mean range in peripheral blood, 52.4 to 88.0%). Eight patients do not require enzyme-replacement therapy, their blood cells continue to express ADA, and they have no signs of defective detoxification of purine metabolites. Nine patients had immune reconstitution with increases in T-cell counts (median count at 3 years, 1.07x10(9) per liter) and normalization of T-cell function. In the five patients in whom intravenous immune globulin replacement was discontinued, antigen-specific antibody responses were elicited after exposure to vaccines or viral antigens. Effective protection against infections and improvement in physical development made a normal lifestyle possible. Serious adverse events included prolonged neutropenia (in two patients), hypertension (in one), central-venous-catheter-related infections (in two), Epstein-Barr virus reactivation (in one), and autoimmune hepatitis (in one).
Gene therapy, combined with reduced-intensity conditioning, is a safe and effective treatment for SCID in patients with ADA deficiency. (ClinicalTrials.gov numbers, NCT00598481 and NCT00599781.)
During the Coronavirus disease 2019 (COVID-19) pandemic, advanced health systems have come under pressure by the unprecedented high volume of patients needing urgent care. The impact on mortality of ...this "patients' burden" has not been determined.
Through retrieval of administrative data from a large referral hospital of Northern Italy, we determined Aalen-Johansen cumulative incidence curves to describe the in-hospital mortality, stratified by fixed covariates. Age- and sex-adjusted Cox models were used to quantify the effect on mortality of variables deemed to reflect the stress on the hospital system, namely the time-dependent number of daily admissions and of total hospitalized patients, and the calendar period. Of the 1225 subjects hospitalized for COVID-19 between February 20 and May 13, 283 died (30-day mortality rate 24%) after a median follow-up of 14 days (interquartile range 5-19). Hospitalizations increased progressively until a peak of 465 subjects on March 26, then declined. The risk of death, adjusted for age and sex, increased for a higher number of daily admissions (adjusted hazard ratio AHR per an incremental daily admission of 10 patients: 1.13, 95% Confidence Intervals CI 1.05-1.22, p = 0.0014), and for a higher total number of hospitalized patients (AHR per an increase of 50 patients in the total number of hospitalized subjects: 1.11, 95%CI 1.04-1.17, p = 0.0004), while was lower for the calendar period after the peak (AHR 0.56, 95%CI 0.43-0.72, p<0.0001). A validation was conducted on a dataset from another hospital where 500 subjects were hospitalized for COVID-19 in the same period. Figures were consistent in terms of impact of daily admissions, daily census, and calendar period on in-hospital mortality.
The pressure of a high volume of severely ill patients suffering from COVID-19 has a measurable independent impact on in-hospital mortality.
Governments continue to update social intervention strategies to contain COVID-19 infections. However, investigation of COVID-19 severity indicators across the population might help to design more ...precise strategies, balancing the need to keep people safe and to reduce the socio-economic burden of generalized restriction precedures. Here, we propose a method for age-sex population-adjusted analysis of disease severity in epidemics that has the advantage to use simple and repeatable variables, which are daily or weekly available. This allows to monitor the effect of public health policies in short term, and to repeat these calculations over time to surveille epidemic dynamics and impact. Our method can help to define a risk-categorization of likeliness to develop a severe COVID-19 disease which requires intensive care or is indicative of a higher risk of dying. Indeed, analysis of suitable open-access COVID-19 data in three European countries indicates that individuals in the 0-40 age interval and females under 60 are significantly less likely to develop a severe condition and die, whereas males equal or above 60 are more likely at risk of severe disease and death. Hence, a combination of age-adaptive and sex-balanced guidelines for social interventions could represent key public health management tools for policymakers.
In pediatric age the prevalence of obesity is high. Obese children who do not have other risk factors than excess weight have been defined as "metabolically healthy obese" (MHO).
The aim of this ...study is to evaluate, in a population of obese children, the prevalence of the MHO and "metabolically unhealthy obese" (MUO) phenotype. Furthermore, we evaluated the distribution of Uric Acid, HOMA index and Waist-Height ratio (W-Hr) in the MHO and MUO sub-groups and the impact of these non-traditional risk factors on the probability to be MUO.
In 1201 obese children and adolescents 54% males, age (±SD) 11.9 (±3.0) years weight, height, waist circumference, systolic (SBP) and diastolic (DBP) blood pressure, pubertal status, glucose, insulin, HDL cholesterol, triglycerides and Uric Acid serum values were assessed. MUO phenotype was defined as the presence of at least one of the following risk factors: SBP or DBP ≥ 90th percentile, glycaemia ≥ 100 mg/dl, HDL cholesterol <40 mg/dl, triglycerides ≥100 mg/dl (children <10 years) or ≥130 mg/dl (children ≥10 years). A multivariate logistic regression analysis was used to estimate the association between MUO phenotype and non-traditional cardiovascular risk factors.
The prevalence of the MUO status was high (61%). MUO subjects were more often male, older and pubertal (
< 0.001). The levels of the three non-traditional risk factors were significantly higher in MUO children compared to MHO children (
< 0.001) and all of them were independent predictors of the fact of being MUO OR 1.41 (95% CI 1.24-1.69); 1.15 (95% CI 1.06-1.23) and 1.03 (95% CI1.01-1.05) for Uric Acid, HOMA index and W-Hr, respectively. About 15% of MHO subjects had serum Uric Acid, HOMA index and W-Hr values within the highest quartile of the study population.
The prevalence of MUO subjects in a large pediatric population is high and serum Uric Acid, HOMA index and W-Hr values are independent predictors of the probability of being MUO. A non-negligible percentage of subjects MHO has high values of all three non-traditional risk factors.
Speed of blast clearance is an indicator of outcome in childhood acute lymphoblastic leukemia (ALL). Availability of measurement of minimal residual disease (MRD) at an early time point with a ...reduced-cost method is of clinical relevance. In the AIEOP-BFM-ALL (Associazione Italiana Ematologia Oncologia Pediatrica and Berlin-Frankfurt-Münster Study Group) 2000 trial, patients were stratified by levels of polymerase chain reaction (PCR) MRD at day +33 and +78. AIEOP studied the prognostic impact of MRD measured by flow cytometry (FCM) at day 15 of induction therapy.
Bone marrow samples from 830 Italian patients were collected on day 15, after 14 days of steroids, and one dose of intrathecal methotrexate, vincristine, daunorubicine, and asparaginase. Cells were analyzed by four-color FCM for detection of leukemia-associated immunophenotypes.
Three patient risk groups were identified by FCM: standard (< 0.1% blast cells; 42% of the total), intermediate (0.1 to < 10%; 47%), and high (> or = 10%; 11%). Their 5-year cumulative incidences of relapse were 7.5% (SE, 1.5), 17.5% (SE, 2.1), and 47.2% (SE, 5.9), respectively. In multivariate analysis, FCM was the most important prognostic factor among those available by day 15, with two-fold and five-fold increase in the risk of relapse compared with patients with less than 0.1%. PCR MRD, when added to the model, had significant prognostic impact; yet high levels of FCM MRD retained an independent ability to detect a significantly higher risk of relapse.
Measurement of FCM MRD in day 15 bone marrow was the most powerful early predictor of relapse, applicable to virtually all patients; it may complement PCR MRD-based stratification including later time points, thus allowing additional treatment tailoring.
In any single-arm trial on novel treatments, assessment of toxicity plays an important role as occurrence of adverse events (AEs) is relevant for application in clinical practice. In the presence of ...a non-fatal time-to-event(s) efficacy endpoint, the analysis should be broadened to consider AEs occurrence in time. The AEs analysis could be tackled with two approaches, depending on the clinical question of interest. Approach 1 focuses on the occurrence of AE as first event. Treatment ability to protect from the efficacy endpoint event(s) has an impact on the chance of observing AEs due to competing risks action. Approach 2 considers how treatment affects the occurrence of AEs in the potential framework where the efficacy endpoint event(s) could not occur.
In the first part of the work we review the strategy of analysis for these two approaches. We identify theoretical quantities and estimators consistent with the following features: (a) estimators should address for the presence of right censoring; (b) theoretical quantities and estimators should be functions of time. In the second part of the work we propose the use of alternative methods (regression models, stratified Kaplan-Meier curves, inverse probability of censoring weighting) to relax the assumption of independence between the potential times to AE and to event(s) in the efficacy endpoint for addressing Approach 2.
We show through simulations that the proposed methods overcome the bias due to the dependence between the two potential times and related to the use of standard estimators.
We demonstrated through simulations that one can handle patients selection in the risk sets due to the competing event, and thus obtain conditional independence between the two potential times, adjusting for all the observed covariates that induce dependence.
The availability of large epidemiological or clinical data storing biological samples allow to study the prognostic value of novel biomarkers, but efficient designs are needed to select a subsample ...on which to measure them, for parsimony and economical reasons. Two-phase stratified sampling is a flexible approach to perform such sub-sampling, but literature on stratification variables to be used in the sampling and power evaluation is lacking especially for survival data.
We compared the performance of different sampling designs to assess the prognostic value of a new biomarker on a time-to-event endpoint, applying a Cox model weighted by the inverse of the empirical inclusion probability.
Our simulation results suggest that case-control stratified (or post stratified) by a surrogate variable of the marker can yield higher performances than simple random, probability proportional to size, and case-control sampling. In the presence of high censoring rate, results showed an advantage of nested case-control and counter-matching designs in term of design effect, although the use of a fixed ratio between cases and controls might be disadvantageous. On real data on childhood acute lymphoblastic leukemia, we found that optimal sampling using pilot data is greatly efficient.
Our study suggests that, in our sample, case-control stratified by surrogate and nested case-control yield estimates and power comparable to estimates obtained in the full cohort while strongly decreasing the number of patients required. We recommend to plan the sample size and using sampling designs for exploration of novel biomarker in clinical cohort data.
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