Predictors of Complicated Disease Course in Children and Adults With Ulcerative Colitis: A Nationwide Study From the epi-IIRN.

BACKGROUND: Data on predictors of complicated ulcerative colitis (UC) course from unselected populations cohorts are scarce. We aimed to utilize a nationwide cohort to explore predictors at diagnosis of disease course in children and adults with UC. METHODS: Data of patients diagnosed with UC since 2005 were retrieved from the nationwide epi-IIRN cohort. Complicated disease course was defined as colectomy, steroid-dependency, or the need for biologic drugs. Hierarchical clustering categorized disease severity at diagnosis based on complete blood count, albumin, C-reactive protein and erythrocyte sedimentation rate (ESR), analyzed together. RESULTS: A total of 13 471 patients with UC (1427 [11%] pediatric-onset) including 103 212 person-years of follow-up were included. Complicated disease course was recorded in 2829 (21%) patients: 1052 (7.9%) escalated to biologics, 1357 (10%) experienced steroid-dependency, and 420 (3.1%) underwent colectomy. Probabilities of complicated disease course at 1 and 5 years from diagnosis were higher in pediatric-onset (11% and 32%, respectively) than adult-onset disease (4% and 16%; P < .001). In a Cox multivariate model, complicated course was predicted by induction therapy with steroids (hazard ratio [HR], 1.5; 95% CI, 1.2-2.0), extraintestinal manifestations (HR, 1.3; 95% CI, 1.03-1.5) and the disease severity clusters of blood tests (HR, 1.8; 95% CI, 1.01-3.1), while induction therapy with enemas (HR, 0.6; 95% CI, 0.5-0.7) and older age (HR, 0.99; 95% CI, 0.98-0.99) were associated with noncomplicated course. CONCLUSION: In this nationwide cohort, the probability of complicated disease course during the first 5 years from diagnosis was 32% in pediatric-onset and 16% in adults with UC and was associated with more severe clusters of routinely collected laboratory tests, younger age at diagnosis, extraintestinal manifestations, and type of induction therapy.

Prognostic factors of complicated disease course are vital for clinical decision-making of early escalation to intensive treatment. In this nationwide cohort, one-third of children and one-fifth of adults with UC developed complicated disease course. Disease course was predicted particularly by routinely collected laboratory tests, age, extraintestinal manifestations, and type of induction therapy at diagnosis.

Impact of Long-COVID in children: a large cohort study.

BACKGROUND: The impact of long-term Coronavirus disease 2019 (COVID-19) on the pediatric population is still not well understood. This study was designed to estimate the magnitude of COVID-19 long-term morbidity 3-6 months after the date of diagnosis. METHODS: A retrospective study of all Clalit Health Services members in Israel aged 1-16 years who tested positive for SARS-CoV-2 between April 1, 2020 and March 31, 2021. Controls, who had no previous diagnosis of COVID-19, were one-to-one matched to 65,548 COVID-19-positive children and teens, and were assigned the infection dates of their matches as their index date. Matching included age, sex, socio-economic score, and societal sector. Individuals were excluded from the study if they had severe medical conditions before the diagnosis such as cancer, diabetes, chronic respiratory diseases, and/or abnormal physiological development. Generalized Estimating Equations were used to estimate the associations between COVID-19 and the use of medical services. The analysis focused on the 3-6 months after the infection date. Adjustments were made for demographics and for the use of medical services 6-12 and 3-6 months before the infection date. The latter was necessary because of observed disparities in medical service utilization between the groups before the COVID-19 diagnosis, despite the matching process. RESULTS: Statistically significant differences were only found for referrals for mental health services [adjusted relative-risk (RR) 1·51, 95%CI 1·15 - 1·96; adjusted risk-difference (RD) 0·001, 95%CI 0·0006 - 0·002], and medication prescriptions of any kind (RR 1·03, 95%CI 1·01-1·06; RD 0·01 95%CI 0·004 - 0·02). CONCLUSIONS: The significant increase in medication prescriptions and mental health service referrals support the hypothesis that COVID-19 is associated with long-lasting morbidities in children and adolescents aged 1-16 years. However, the risk difference in both instances was small, suggesting a minor impact on medical services.

Early Initiation of Biologics and Disease Outcomes in Adults and Children With Inflammatory Bowel Diseases: Results From the Epidemiology Group of the Nationwide Israeli Inflammatory Bowel Disease Research Nucleus Cohort.

BACKGROUND & AIMS: In this nationwide study, we explored whether early initiation of biologics is associated with improved outcomes in children and adults with Crohn's disease (CD) and ulcerative colitis (UC). METHODS: All patients diagnosed with CD or UC in Israel (2005-2020) were included in the Epidemiology Group of the Israeli Inflammatory Bowel Disease Research Nucleus cohort, encompassing 98% of the population. We compared disease duration at biologics initiation (ie, 0-3 months, >3-12 months, >1-2 years, and >2-3 years) using the cloning, censoring, and weighting by inverse probabilities method to emulate a target trial, adjusting for time-varying confounders and selection bias. RESULTS: Of the 34,375 included patients (of whom 5240 [15%] were children), 7452 of 19,264 (39%) with CD and 2235 of 15,111 (15%) with UC received biologics. In CD, by 10 years postdiagnosis, the probability of CD-related surgery decreased gradually but modestly with earlier initiation of biologics; a significant difference was noted between >2-3 years (31%) and 0-3 months (18%; P = .02; number needed to treat, 7.7), whereas there was no difference between the 0-3-month and >3-12-month periods. The 10-year probability of steroid dependency for the 0-3-month period (19%) differed both from the >2-3-year (31%; P < .001) and 1-2-year periods (37%; P < .001). In UC, no significant differences in colectomy or steroid dependency rates were observed between the treatment initiation periods. Similar trends were noted in the pediatric population. CONCLUSIONS: Very early initiation of biologics was not associated with some outcomes except for a modest risk reduction of surgery and steroid dependency for CD, which requires confirmation in future studies. In UC, early introduction of biologics was not associated with reduced risk of colectomy or steroid dependency.

Predictors of Complicated Disease Course in Adults and Children With Crohn's Disease: A Nationwide Study from the epi-IIRN.

BACKGROUND: Since data on predictors of complicated Crohn's disease (CD) from unselected populations are scarce, we aimed to utilize a large nationwide cohort, the epi-IIRN, to explore predictors of disease course in children and adults with CD. METHODS: Data of patients with CD were retrieved from Israel's 4 health maintenance organizations, whose records cover 98% of the population (2005-2020). Time-to-event modeled a complicated disease course, defined as CD-related surgery, steroid-dependency, or the need for >1 class of biologics. Hierarchical clustering categorized disease severity at diagnosis based on available laboratory results. RESULTS: A total of 16 659 patients (2999 [18%] pediatric-onset) with 121 695 person-years of follow-up were included; 3761 (23%) had a complicated course (750 [4.5%] switched to a second biologic class, 1547 [9.3%] steroid-dependency, 1463 [8.8%] CD-related surgery). Complicated disease was more common in pediatric- than adult-onset disease (26% vs 22%, odds ratio, 1.3; 95% confidence interval [CI], 1.2-1.4). In a Cox multivariate model, complicated disease was predicted by induction therapy with biologics (hazard ratio [HR], 2.1; 95% CI, 1.2-3.6) and severity of laboratory tests at diagnosis (HR, 1.7; 95% CI, 1.2-2.2), while high socioeconomic status was protective (HR, 0.94; 95% CI, 0.91-0.96). In children, laboratory tests predicted disease course (HR, 1.8; 95% CI, 1.2-2.5), as well as malnutrition (median BMI Z score -0.41; 95% CI, -1.42 to 0.43 in complicated disease vs -0.24; 95% CI, -1.23 to 0.63] in favorable disease; P < .001). CONCLUSIONS: In this nationwide cohort, CD course was complicated in one-fourth of patients, predicted by laboratory tests, type of induction therapy, socioeconomic status, in addition to malnutrition in children.

Prognostic factors of complicated disease course are vital for considering early escalation to biologics. In this nationwide cohort, complicated disease course was apparent in approximately one-fourth of patients and was predicted particularly by routinely collected laboratory tests, age, and type of induction therapy at diagnosis.

Distinguishing Immunologic and Behavioral Effects of Vaccination.

The interpretation of vaccine efficacy estimands is subtle, even in randomized trials designed to quantify the immunologic effects of vaccination. In this article, we introduce terminology to distinguish between different vaccine efficacy estimands and clarify their interpretations. This allows us to explicitly consider the immunologic and behavioral effects of vaccination, and establish that policy-relevant estimands can differ substantially from those commonly reported in vaccine trials. We further show that a conventional vaccine trial allows the identification and estimation of different vaccine estimands under plausible conditions if one additional post-treatment variable is measured. Specifically, we utilize a "belief variable" that indicates the treatment an individual believed they had received. The belief variable is similar to "blinding assessment" variables that are occasionally collected in placebo-controlled trials in other fields. We illustrate the relations between the different estimands, and their practical relevance, in numerical examples based on an influenza vaccine trial.

Ambient temperature and preeclampsia: A historical cohort study.

Previous studies found inconsistent associations between ambient temperature during pregnancy and the risk of preeclampsia. If such associations are causal, they may impact the future burden of preeclampsia in the context of climate change. We used a historical cohort of 129,009 pregnancies (5074 preeclampsia cases) from southern Israel that was merged with temperature assessments from a hybrid satellite-based exposure model. Distributed-lag and cause-specific hazard models were employed to study time to all preeclampsia cases, followed by stratification according to early (≤34 weeks) and late (>34 weeks) onset disease and identify critical exposure periods. We found a positive association between temperature and preeclampsia during gestation, which was stronger in the 3rd trimester. For example, during week 33, compared to the reference temperature of 22.4 °C, the cause-specific hazard ratio (HRCS) of preeclampsia was 1.01 (95% confidence interval (CI): 1.01-1.02) when exposed to 30 °C, 1.05 (95%CI: 1.03-1.08) at 35 °C, and 1.07 (95%CI: 1.04-1.10) at 37 °C. The associations existed with both early- and late-onset preeclampsia; however, the associations with the early-onset disease were somewhat stronger, limited to the first weeks of pregnancy and the third trimester, and with larger confidence intervals. The HRCS for early preeclampsia onset, when exposed to 37 °C compared to 22.4 °C during week 33, was 1.12 (95%CI: 0.96-1.30), and for late-onset preeclampsia, the HRCS was 1.09 (95%CI: 1.05-1.13). To conclude, exposure to high temperatures at the beginning and, particularly, the end of gestation is associated with an increased risk of preeclampsia in southern Israel.

Prenatal and postnatal exposure to NO2 and rapid infant weight gain - A population-based cohort study.

BACKGROUND: Childhood overweight and obesity is a global public health problem. Rapid infant weight gain is predictive of childhood overweight. Studies found that exposure to ambient air pollution is associated with childhood overweight, and have linked prenatal exposure to air pollution with rapid infant weight gain. OBJECTIVES: To examine the association between prenatal and postnatal ambient NO2 exposure, a traffic-related marker, with rapid weight gain in infants. METHODS: We carried out a population-based historical cohort study using data from the Israeli national network of maternal and child health clinics. The study included 474,136 infants born at term with birthweight ≥2500 g in 2011-2019 in central Israel. Weekly averages of NO2 concentration throughout pregnancy (prenatal) and the first 4 weeks of life (postnatal) were assessed using an optimized dispersion model and were linked to geocoded home addresses. We modelled weight gain velocity throughout infancy using the SuperImposition by Translation and Rotation (SITAR) method, a mixed-effects nonlinear model specialized for modelling growth curves, and defined rapid weight gain as the highest velocity tertile. Distributed-lag models were used to assess critical periods of risk and to measure relative risks for rapid weight gain. Adjustments were made for socioeconomic status, population group, subdistrict, month and year of birth, and the alternate exposure period - prenatal or postnatal. RESULTS: The cumulative adjusted relative risk for rapid weight gain of NO2 exposure was 1.02 (95% confidence intereval [CI] 1.00, 1.04) for exposure throughout pregnancy and 1.02 (95% CI 1.01, 1.04) for exposure during the first four postnatal weeks per NO2 interquartile range increase (7.3 ppb). An examination of weekly associations revealed that the critical period of risk for the prenatal exposure was from mid-pregnancy to birth. CONCLUSIONS: Prenatal and postnatal exposures to higher concentrations of traffic-related air pollution are each independently associated with rapid infant weight gain, a risk factor for childhood overweight and obesity.

The time-varying association between previous antibiotic use and antibiotic resistance.

OBJECTIVES: The objective of the study was to estimate how the time elapsed from previous antibiotic use is associated with antibiotic resistance. METHODS: Data comprised electronic medical records of all patients in an Israeli hospital who had a positive bacterial culture from 2016 to 2019. These included susceptibility testing results and clinical and demographic data. Mixed-effects time-varying logistic models were fitted to estimate the association between the time elapsed since the last use of aminoglycosides and gentamicin resistance (n = 13 095), cephalosporins and ceftazidime resistance (n = 13 051), and fluoroquinolones and ciprofloxacin resistance (n = 15 364) while adjusting for multiple covariates. RESULTS: For all examined antibiotics, previous antibiotic use had a statistically significant association with resistance (p < 0.001). These associations exhibited a clear decreasing pattern over time, which we present as a flexible function of time. Nonetheless, previous antibiotic use remained a significant risk factor for resistance for at least 180 days when the adjusted ORs were 1.94 (95% CI, 1.40-2.69), 1.33 (95% CI, 1.10-1.61), and 2.25 (95% CI, 1.49-3.41) for gentamicin, ceftazidime, and ciprofloxacin, respectively. DISCUSSION: The association between prior antibiotic use and resistance decreases over time. Commonly used cut-offs for prior antibiotic use can either misclassify patients still at higher risk when too recent or provide a diluted estimate of the effects of antibiotic use on future resistance when too distant. Hence, prior antibiotic use should be considered a time-dependent risk factor for resistance in both epidemiological research and clinical practice.

A sensitivity analysis approach for the causal hazard ratio in randomized and observational studies.

The hazard ratio (HR) is often reported as the main causal effect when studying survival data. Despite its popularity, the HR suffers from an unclear causal interpretation. As already pointed out in the literature, there is a built-in selection bias in the HR, because similarly to the truncation by death problem, the HR conditions on post-treatment survival. A recently proposed alternative, inspired by the Survivor Average Causal Effect, is the causal HR, defined as the ratio between hazards across treatment groups among the study participants that would have survived regardless of their treatment assignment. We discuss the challenge in identifying the causal HR and present a sensitivity analysis identification approach in randomized controlled trials utilizing a working frailty model. We further extend our framework to adjust for potential confounders using inverse probability of treatment weighting. We present a Cox-based and a flexible non-parametric kernel-based estimation under right censoring. We study the finite-sample properties of the proposed estimation methods through simulations. We illustrate the utility of our framework using two real-data examples.

Assessing COVID-19 vaccination strategies in varied demographics using an individual-based model.

Background: New variants of SARS-CoV-2 are constantly discovered. Administration of COVID-19 vaccines and booster doses, combined with the application of non-pharmaceutical interventions (NPIs), is often used to prevent outbreaks of emerging variants. Such outbreak dynamics are further complicated by the population's behavior and demographic composition. Hence, realistic simulations are needed to estimate the efficiency of proposed vaccination strategies in conjunction with NPIs. Methods: We developed an individual-based model of COVID-19 dynamics that considers age-dependent parameters such as contact matrices, probabilities of symptomatic and severe disease, and households' age distribution. As a case study, we simulate outbreak dynamics under the demographic compositions of two Israeli cities with different household sizes and age distributions. We compare two vaccination strategies: vaccinate individuals in a currently prioritized age group, or dynamically prioritize neighborhoods with a high estimated reproductive number. Total infections and hospitalizations are used to compare the efficiency of the vaccination strategies under the two demographic structures, in conjunction with different NPIs. Results: We demonstrate the effectiveness of vaccination strategies targeting highly infected localities and of NPIs actively detecting asymptomatic infections. We further show that different optimal vaccination strategies exist for each sub-population's demographic composition and that their application is superior to a uniformly applied strategy. Conclusion: Our study emphasizes the importance of tailoring vaccination strategies to subpopulations' infection rates and to the unique characteristics of their demographics (e.g., household size and age distributions). The presented simulation framework and findings can help better design future responses against the following emerging variants.

Estimating the impact of cefuroxime versus cefazolin and amoxicillin/clavulanate use on future collateral resistance: a retrospective comparison.

BACKGROUND: Quantitative estimates of collateral resistance induced by antibiotic use are scarce. OBJECTIVES: To estimate the effects of treatment with amoxicillin/clavulanate or cefazolin, compared with cefuroxime, on future resistance to ceftazidime among hospitalized patients. METHODS: A retrospective analysis of patients with positive bacterial cultures hospitalized in an Israeli hospital during 2016-19 was conducted. Patients were restricted to those treated with amoxicillin/clavulanate, cefazolin or cefuroxime and re-hospitalized with a positive bacterial culture during the following year. Matching was performed using exact, Mahalanobis and propensity score matching. Each patient in the amoxicillin/clavulanate and cefazolin groups was matched to a single patient from the cefuroxime group, yielding 185:185 and 298:298 matched patients. Logistic regression and the g-formula (standardization) were used to estimate the OR, risk difference (RD) and number needed to harm (NNH). RESULTS: Cefuroxime induced significantly higher resistance to ceftazidime than amoxicillin/clavulanate or cefazolin; the marginal OR was 1.76 (95% CI = 1.16-2.83) compared with amoxicillin/clavulanate and 1.98 (95% CI = 1.41-2.8) compared with cefazolin and the RD was 0.118 (95% CI = 0.031-0.215) compared with amoxicillin/clavulanate and 0.131 (95% CI = 0.058-0.197) compared with cefazolin. We also estimated the NNH; replacing amoxicillin/clavulanate or cefazolin with cefuroxime would yield ceftazidime resistance in 1 more patient for every 8.5 (95% CI = 4.66-32.14) or 7.6 (95% CI = 5.1-17.3) patients re-hospitalized in the following year, respectively. CONCLUSIONS: Our results indicate that treatment with amoxicillin/clavulanate or cefazolin is preferable to cefuroxime, in terms of future collateral resistance. The results presented here are a first step towards quantitative estimations of the ecological damage caused by different antibiotics.

Perianal Crohn Disease Is More Common in Children and Is Associated With Complicated Disease Course Despite Higher Utilization of Biologics: A Population-based Study From The epidemiology group of the Israeli IBD Research Nucleus (epiIIRN).

BACKGROUND AND OBJECTIVES: Both perianal and pediatric-onset Crohn disease (CD) disease are associated with complicated disease course and higher drug utilization. we aimed to explore the differences between pediatric and adult-onset perianal CD and their disease course. METHODS: We included all patients with newly diagnosed CD from 2005 to 2019 at two Israeli Health Maintenance Organizations, covering 78% of the population. A combination of ICD-9 codes, radiology and procedures was used to define fistulizing perianal CD (PCD) and its severity according to the association with simple and complex perianal disease. RESULTS: A total of 12,905 patients were included (2186 [17%] pediatric-onset, 10,719 [83%] adults), with a median follow-up of 7.8 years. PCD was diagnosed in 1530 (12%) patients, with higher incidence in children (308 [14%] children vs 1222 adults [11%]; P  < 0.001). Children had higher incidence of severe PCD (141/308 [47%] vs 433/1222 [35%]; P < 0.001). At 5 years, children with PCD were more likely than adults to be treated with biologics (212 [69%] vs 515 [42%]; odds ratio [OR] 2.6 [95% confidence interval (CI) 1.6-4.0]; P < 0.001) and immunomodulators (238 [74%] vs 643 [53%]; OR 2.8 [95% CI 2.1-3.6]; P < 0.001). PCD in children was still associated with poorer disease outcomes as shown for surgeries (36 [12%] vs 93 [8%]; P = 0.02) and steroid-dependency (52 [17%] vs 156 [13%]; P < 0.001). Multivariable modeling indicated that the severity of PCD is a stronger predictor of disease course than age. CONCLUSION: PCD is more common in pediatric-onset CD and is associated with higher drug utilization and worse disease outcomes, in large due to higher rate of severe PCD in children.

Indirect protection of children from SARS-CoV-2 infection through parental vaccination.

Children not vaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may still benefit from vaccines through protection from vaccinated contacts. We estimated the protection provided to children through parental vaccination with the BNT162b2 vaccine. We studied households without prior infection consisting of two parents and unvaccinated children, estimating the effect of parental vaccination on the risk of infection for unvaccinated children. We studied two periods separately-an early period (17 January 2021 to 28 March 2021; Alpha variant, two doses versus no vaccination) and a late period (11 July 2021 to 30 September 2021; Delta variant, booster dose versus two vaccine doses). We found that having a single vaccinated parent was associated with a 26.0 and a 20.8% decreased risk in the early and late periods, respectively, and having two vaccinated parents was associated with a 71.7 and a 58.1% decreased risk, respectively. Thus, parental vaccination confers substantial protection on unvaccinated children in the household.

Causal inference for semi-competing risks data.

The causal effects of Apolipoprotein E $\epsilon4$ allele (APOE) on late-onset Alzheimer's disease (AD) and death are complicated to define because AD may occur under one intervention but not under the other, and because AD occurrence may affect age of death. In this article, this dual outcome scenario is studied using the semi-competing risks framework for time-to-event data. Two event times are of interest: a nonterminal event time (age at AD diagnosis), and a terminal event time (age at death). AD diagnosis time is observed only if it precedes death, which may occur before or after AD. We propose new estimands for capturing the causal effect of APOE on AD and death. Our proposal is based on a stratification of the population with respect to the order of the two events. We present a novel assumption utilizing the time-to-event nature of the data, which is more flexible than the often-invoked monotonicity assumption. We derive results on partial identifiability, suggest a sensitivity analysis approach, and give conditions under which full identification is possible. Finally, we present and implement nonparametric and semiparametric estimation methods under right-censored semi-competing risks data for studying the complex effect of APOE on AD and death.

Resumption of sexual activity after acute myocardial infarction and long-term survival.

AIMS: Sexual activity is an important factor in the overall quality of life. We examined whether resumption of sexual activity frequency within the first few months after myocardial infarction (MI) is associated with long-term survival. METHODS AND RESULTS: Sexually active patients aged ≤65 years (n = 495; median age, 53 years), drawn from the longitudinal Israel Study of First Acute Myocardial Infarction, were interviewed during the index hospitalization (1992-93) and after 3-6 months. Resumption of sexual activity was defined as abstaining/decreasing or maintaining/increasing according to self-reported frequency post- vs. pre-MI. Patients were followed for all-cause and cause-specific mortality through national registries. A propensity score for sexual activity resumption was calculated, based on which inverse probability weighted Cox models were constructed to examine associations. Patients who maintained/increased frequency [n = 263 (53%)] were more likely to be of higher socioeconomic status and to express lower levels of depression than their abstained/decreased counterparts. In the propensity score-weighted synthetic sample, the distribution of measured baseline covariates was similar across exposure categories. During a median follow-up of 22 years, 211 (43%) patients died. Maintaining/increasing sexual activity frequency was inversely associated with all-cause mortality [hazard ratio (HR) 0.65, 95% confidence interval (CI) 0.48-0.88], compared with abstaining/reducing. The inverse association was more robust for non-cardiovascular mortality (HR 0.56, 95% CI 0.36-0.85) than cardiovascular mortality (HR 0.90, 95% CI 0.53-1.51). CONCLUSIONS: Resumption of sexual activity frequency within the first months after MI was strongly associated with improved long-term survival, highlighting the need for sexual counselling shortly after MI.

Perianal Crohn's Disease Is Associated With Poor Disease Outcome: A Nationwide Study From the epiIIRN Cohort.

BACKGROUND & AIMS: Limited population-based data have explored perianal involvement in Crohn's disease (CD) and compared the disease course between severe and non-severe perianal CD (PCD). We aimed to explore the disease course of these phenotypes in a population-based study of CD. METHODS: Cases were identified from the epi-IIRN cohort and included 2 Israeli health maintenance organizations covering 78% of the population. We validated specific algorithms to identify fistulizing PCD and to differentiate severe from non-severe disease by medication utilization, International Classification of Disease, 9th Revision codes, and perianal procedures. RESULTS: A total of 12,904 CD patients were included in an inception cohort from 2005 (2186 pediatric-onset, 17%) providing 86,119 person-years of follow-up. Fistulizing PCD was diagnosed in 1530 patients (12%) (574 with severe PCD, 4%). The prevalence of PCD was 7.9%, 9.4%, 10.3%, and 11.6% at 1, 3, 5, and 10 years from CD diagnosis, respectively. At 5 years, PCD patients were more likely to be hospitalized (36% in non-PCD vs 64% in PCD; P < .001), undergo inflammatory bowel disease-related surgeries (9% vs 38%, respectively; P < .001), and develop anorectal cancer (1.2/10,000 person-years for non-PCD vs 4.2/10,000 for PCD; P = .01). Severe PCD was associated with poorer outcomes compared with non-severe PCD, as shown for hospitalizations (61% in non-severe PCD vs 73% in severe; P = .004) and surgeries (35% vs 43%; P = .001). CONCLUSIONS: Despite higher utilization of immunomodulators and biologics, PCD is associated with poor disease outcomes, especially in severe PCD.

Modeling semi-competing risks data as a longitudinal bivariate process.

As individuals age, death is a competing risk for Alzheimer's disease (AD) but the reverse is not the case. As such, studies of AD can be placed within the semi-competing risks framework. Central to semi-competing risks, and in contrast to standard competing risks , is that one can learn about the dependence structure between the two events. To-date, however, most methods for semi-competing risks treat dependence as a nuisance and not a potential source of new clinical knowledge. We propose a novel regression-based framework that views the two time-to-event outcomes through the lens of a longitudinal bivariate process on a partition of the time scales of the two events. A key innovation of the framework is that dependence is represented in two distinct forms, local and global dependence, both of which have intuitive clinical interpretations. Estimation and inference are performed via penalized maximum likelihood, and can accommodate right censoring, left truncation, and time-varying covariates. An important consequence of the partitioning of the time scale is that an ambiguity regarding the specific form of the likelihood contribution may arise; a strategy for sensitivity analyses regarding this issue is described. The framework is then used to investigate the role of gender and having ≥1 apolipoprotein E (APOE) ε4 allele on the joint risk of AD and death using data from the Adult Changes in Thought study.

Improved Outcomes of Paediatric and Adult Crohn's Disease and Association With Emerging Use of Biologics-A Nationwide Study From the Epi-IIRN.

BACKGROUND: The effectiveness of biologics for improving long-term outcomes in patients with Crohn's disease [CD] is still controversial. In this nationwide study, we aimed to evaluate trends of long-term outcomes in all CD patients in Israel during the biologics era. METHODS: Trends of outcomes were analysed using data from the four Israeli health maintenance organisations, covering 98% of the population; joinpoint regression models were used to explore changes of these trends over 2005 to 2019. RESULTS: A total of 16 936 patients were diagnosed with CD in Israel since 2005 (2932 [17%] paediatric onset, 14 004 [83%] adult onset) with 114 947 person-years of follow-up. The cumulative rate of any CD related surgery was 5%, 9%, 11%, and 14% at 1, 3, 5, and 10 years from diagnosis. The increase in use of biologics was sharp (from 8.9% to 36%; average annual percent change [AAPC], 14.3%), and the time to biologics was shorter in recent years (median time of 4.8 [1.9-8.1] years in those diagnosed in 2005-2008 compared with 0.5 [0.2-1.1] years in those diagnosed in 2015-2018; p < 0.001). A significant decrease was noted in the hazard of hospitalisations (1.3 [0.1-4.6] years compared with 0.2 [0.02-0.9] years; p < 0.001), steroid dependency (1.5 [0.2-5.4] years compared with 0.1 [0.02-0.4] years; p < 0.001), and intestinal surgeries [4.7 [1.6-8.2] years compared with 0.6 [0.2-1.4] years; p < 0.001), but not of perianal surgery (4.2 [1.1-7.7] years compared with 0.6 [0.2-1.4] years; p = 0.2). Outcomes were consistently worse in paediatric onset compared with adults. CONCLUSIONS: The rates of hospitalisations, steroid dependency, and intestinal resections decreased in association with increased use of biologics both in children and in adults, but not the rate of perianal surgeries.

COVID-19 Vaccine Is Effective in Inflammatory Bowel Disease Patients and Is Not Associated With Disease Exacerbation.

BACKGROUND & AIMS: Studies have shown decreased response to coronavirus disease 2019 (COVID-19) vaccinations in some populations. In addition, it is possible that vaccine-triggered immune activation could trigger immune dysregulation and thus exacerbate inflammatory bowel diseases (IBD). In this population-based study we used the epi-Israeli IBD Research Nucleus validated cohort to explore the effectiveness of COVID-19 vaccination in IBD and to assess its effect on disease outcomes. METHODS: We included all IBD patients insured in 2 of the 4 Israeli health maintenance organizations, covering 35% of the population. Patients receiving 2 Pfizer-BioNTech BNT162b2 vaccine doses between December 2020 and June 2021 were individually matched to non-IBD controls. To assess IBD outcomes, we matched vaccinated to unvaccinated IBD patients, and response was analyzed per medical treatment. RESULTS: In total, 12,109 IBD patients received 2 vaccine doses, of whom 4946 were matched to non-IBD controls (mean age, 51 ± 16 years; median follow-up, 22 weeks; interquartile range, 4-24). Fifteen patients in each group (0.3%) developed COVID-19 after vaccination (odds ratio, 1; 95% confidence interval, 0.49-2.05; P = 1.0). Patients on tumor necrosis factor (TNF) inhibitors and/or corticosteroids did not have a higher incidence of infection. To explore IBD outcomes, 707 vaccinated IBD patients were compared with unvaccinated IBD patients by stringent matching (median follow-up, 14 weeks; interquartile range, 2.3-20.4). The risk of exacerbation was 29% in the vaccinated patients compared with 26% in unvaccinated patients (P = .3). CONCLUSIONS: COVID-19 vaccine effectiveness in IBD patients is comparable with that in non-IBD controls and is not influenced by treatment with TNF inhibitors or corticosteroids. The IBD exacerbation rate did not differ between vaccinated and unvaccinated patients.