Peer victimization, posttraumatic stress symptoms, and chronic pain: A longitudinal examination

Chronic pain and posttraumatic stress disorder symptoms (PTSS) co-occur at high rates in youth and are linked to worse pain outcomes and quality of life. While peer victimization has been posited as a mechanism underlying the PTSS-pain relationship in youth, empirical evidence suggests that it may exacerbate both PTSS and pain. The present study aimed to longitudinally examine PTSS as a mediator in the relationship between peer victimization at baseline and pain-related outcomes at 3 months in youth with chronic pain. Participants included 182 youth aged 10-18 years recruited from a tertiary level children's hospital in Western Canada. At baseline, participants completed measures to assess pain (intensity and interference), peer victimization (relational and overt), and PTSS. Pain was re-assessed at 3-month follow-up. Primary hypotheses were tested utilizing a series of mediation analyses with PTSS as a proposed mediator in the associations between peer victimization and pain outcomes. Youth PTSS mediated the relationship between higher baseline relational victimization and higher 3-month pain interference, while controlling for baseline pain interference. Three-month pain intensity was not correlated with peer victimization; thus, pain intensity was not included in analyses. These findings reveal that PTSS may be an underlying factor in the co-occurrence of peer victimization and chronic pain in youth. Further research is needed to better understand the role of peer victimization in the maintenance of chronic pain to ensure appropriate, effective, and timely interventions that address the social and mental health issues impacting the lives of these youth as well as their pain. PERSPECTIVE: PTSS may be an underlying factor in the co-occurrence between peer victimization and chronic pain in youth, highlighting the need to assess for both peer relationship problems and PTSS in youth with chronic pain.

Clonal Parabacteroides from Gut Microfistulous Tracts as Transmissible Cytotoxic Succinate-Commensal Model of Crohn's Disease Complications

Crohn's disease (CD) has been traditionally viewed as a chronic inflammatory disease that cause gut wall thickening and complications, including fistulas, by mechanisms not understood. By focusing on Parabacteroides distasonis (presumed modern succinate-producing commensal probiotic), recovered from intestinal microfistulous tracts (cavernous fistulous micropathologies CavFT proposed as intermediate between 'mucosal fissures' and 'fistulas') in two patients that required surgery to remove CD-damaged ilea, we demonstrate that such isolates exert pathogenic/pathobiont roles in mouse models of CD. Our isolates are clonally-related; potentially emerging as transmissible in the community and mice; proinflammatory and adapted to the ileum of germ-free mice prone to CD-like ileitis (SAMP1/YitFc) but not healthy mice (C57BL/6J), and cytotoxic/ATP-depleting to HoxB8-immortalized bone marrow derived myeloid cells from SAMP1/YitFc mice when concurrently exposed to succinate and extracts from CavFT-derived E. coli , but not to cells from healthy mice. With unique genomic features supporting recent genetic exchange with Bacteroides fragilis -BGF539, evidence of international presence in primarily human metagenome databases, these CavFT Pdis isolates could represent to a new opportunistic Parabacteroides species, or subspecies (' cavitamuralis' ) adapted to microfistulous niches in CD.

Ultrabroadband flying-focus using an axiparabola-echelon pair

Flying-focus pulses promise to revolutionize laser-driven secondary sources by decoupling the trajectory of the peak intensity from the native group velocity of the medium over distances much longer than a Rayleigh range. Previous demonstrations of the flying focus have either produced an uncontrolled trajectory or a trajectory that is engineered using chromatic methods that limit the duration of the peak intensity to picosecond scales. Here we demonstrate a controllable ultrabroadband flying focus using a nearly achromatic axiparabola-echelon pair. Spectral interferometry using an ultrabroadband superluminescent diode was used to measure designed super- and subluminal flying-focus trajectories and the effective temporal pulse duration as inferred from the measured spectral phase. The measurements demonstrate that a nearly transform- and diffraction-limited moving focus can be created over a centimeter-scale-an extended focal region more than 50 Rayleigh ranges in length. This ultrabroadband flying-focus and the novel axiparabola-echelon configuration used to produce it are ideally suited for applications and scalable to >100 TW peak powers.

Coronary artery calcium scoring for cardiovascular risk assessment in patients with inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is associated with higher incidence of atherosclerotic cardiovascular disease (ASCVD). Data investigating the role of coronary artery calcium (CAC) scoring in identifying subclinical atherosclerotic disease in IBD patients is scarce.

METHODS

Using data obtained from the CLARIFY registry, a prospective study of no-charge coronary artery calcium (CAC) testing at University Hospitals, we reviewed patients with ulcerative colitis (UC) or Crohn's disease (CD) who underwent CAC scoring from 2014 to 2020. We investigated the concordance between CAC risk and 10-year estimated ASCVD risk by AHA/ACC pooled cohort equation using pre-established thresholds for statin prescription (CAC≥100, 10-year ASCVD risk ≥7.5%). We additionally investigated the association between CAC, preventive therapy initiation and Major Adverse Cardiovascular Events (MACE).

RESULTS

A total of 369 patients with IBD were included (174 UC, 195 CD), with median age of 60 years. The median CAC score was 14.9 with no significant difference between UC and CD (P = .76). Overall, 151 (41%) had CAC of 0, 108 (29%) had CAC 1-99, 61 (17%) had CAC 100 to 399, and 49 (13%) had CAC ≥400 with no difference in CAC distribution between CD and UC (P = .17). There was no difference in median CAC between IBD or age/sex-matched controls (P = .34). Approximately half of the patients (52%) with IBD had 10-year estimated ASCVD risk of 7.5% or higher. Among patients with ASCVD risk <7.5% (n = 163), 29 (18%) had CAC≥100 and among patients with ASCVD risk ≥7.5% (n = 178), 102 (57%) had CAC <100. There was no difference between CAC<100 vs CAC≥100 with respect to CRP, use of immunosuppressive or amino-salicylate therapy, IBD severity or complications. CAC score (AUROC 0.67 [0.56-0.78]), but not PCE ASCVD risk (AUROC 0.60 [0.48-0.73]), was predictive of MACE. The best cut-off for CAC score was 76 (sensitivity = 60%, specificity = 69%), and was associated with 4-fold increase in MACE (Hazard Ratio 4.0 [2.0-8.1], P < .001).

CONCLUSION

Subclinical atherosclerosis, as evaluated by CAC scoring, is prevalent in patients with IBD, and is associated with cardiovascular events. Further studies are needed to understand underlying biological processes of increased atherosclerotic disease risk among adults with IBD.

Sweets and Inflammatory Bowel Disease: Patients Favor Artificial Sweeteners and Diet Foods/Drinks Over Table Sugar and Consume Less Fruits/Vegetables

BACKGROUND

While artificial sweeteners are deemed safe, preclinical studies indicate that artificial sweeteners contribute to gastrointestinal inflammation. Little is known about patients' perceptions and consumption of artificial sweeteners in inflammatory bowel disease (IBD). We surveyed the consumption frequency and beliefs of IBD patients and control participants regarding artificial sweeteners.

METHODS

We surveyed 130 individuals (IBD patients, n = 93; control/non-IBD participants, n = 37) among our tertiary hospital population to determine consumption frequency and beliefs regarding artificial sweeteners (Splenda/sucralose, Stevia/stevia, NutraSweet/Equal/aspartame). A 14-question questionnaire surveyed the frequency of 9 dietary habits, preferences, and beliefs on health benefits of commercial artificial sweeteners, using the following as positive and negative control questions: table sugar, water, fruits/vegetables, and coconut-oil, among others.

RESULTS

Despite the similarity in yes/no consumption data, artificial sweeteners (Q4 t test P = .023) and diet (low calorie) foods/drinks (Q4 t test P = .023) were consumed more frequently by patients with IBD than by control participants, while no difference in preference for water instead of juices/sodas was observed between IBD patients and control participants. Conversely, patients with IBD consumed table sugar less frequently than control participants (Q1 t test-P = .09), in agreement with their reporting of sugary foods as cause of symptoms (P < .01). A positive correlation was observed between artificial sweeteners and fresh fruits/vegetables among the first 31 IBD patients (Spearman P = .017) and confirmed with 62 new IBD patients (r = 0.232; 95% CI, 0.02-0.43; P = .031), indicating that artificial sweeteners are deemed a healthy habit in IBD. Excluding fresh fruits/vegetables, multivariate analyses to develop surrogate principal component analysis indexes of healthy habits confirmed that artificial sweeteners consumption follows healthy preferences among our IBD patients (adjusted P < .0001).

CONCLUSIONS

Consumption of artificial sweeteners correlated with healthy habits, suggesting that our IBD population deemed artificial sweeteners as healthy and/or had preferences for naturally or artificially sweetened flavors and products.

Prevalence Rates of Pneumococcal Vaccination in IBD and 30-Day Clinical Outcomes in Patients With IBD and Pneumococcal Disease Stratified by Receipt of Pneumococcal Vaccination: A Multi-Network Study

This study sought to assess outcomes associated with pneumococcal vaccination in adult inflammatory bowel disease patients. Results found unvaccinated patients had higher adverse outcomes, including greater risk of hospitalization, ICU admission, ventilation, and mortality. These findings underscore the importance of pneumococcal vaccination.

Predictors of Hospital-related Outcomes of COVID-19 Infection in Patients With Inflammatory Bowel Disease in the Early Pandemic Phase: A Nationwide Inpatient Database Survey

BACKGROUND

Patients with inflammatory bowel disease (IBD) are at higher risk for severe COVID-19 infection. However, most studies are single-center, and nationwide data in the United States are lacking. This study aimed to investigate hospital-related outcomes and predictors of these outcomes in patients with IBD and COVID-19 infection.

METHODS

The National Inpatient Sample and National Readmission database were queried for all the patient hospitalizations with IBD with concurrent COVID-19 in the study group and non-COVID-19 related hospitalizations in the control group. For patients under 18 years, elective and trauma-related hospitalizations were excluded. Primary outcomes included mortality, septic shock, mechanical ventilation, and intensive care utilization. Secondary outcomes included length of stay and total hospitalization costs.

RESULTS

From this query, 8865 adult patients with IBD and COVID-19 were identified. These patients were relatively older (62.8 vs 57.7 years, P < .01), and the majority were females (52.1% with COVID-19 vs 55.2% without COVID-19). Patients with IBD and COVID-19 had higher mortality (12.24% vs 2.55%; P < .01), increased incidence of septic shock (7.9% vs 4.4%; P < .01), mechanical ventilation (11.5% vs 3.7%; P < .01), and intensive care utilization (12% vs 4.6%; P < .01). These patients also had higher mean length of stay (8.28 days vs 5.47 days; P < .01) and total hospitalization costs ($21 390 vs $16 468; P < .01) than those without COVID-19 infection.

CONCLUSIONS

Patients with IBD and COVID-19 have worse outcomes, with a higher incidence of severe COVID-19 disease, leading to higher mortality rates, longer lengths of stay, and increased total hospitalization costs. Encouraging preventive health measures and treating promptly with advanced COVID-19 therapies may improve outcomes and decrease the healthcare burden.

Vulnerable newborn types: analysis of subnational, population-based birth cohorts for 541 285 live births in 23 countries, 2000-2021

OBJECTIVE

To examine prevalence of novel newborn types among 541 285 live births in 23 countries from 2000 to 2021.

DESIGN

Descriptive multi-country secondary data analysis.

SETTING

Subnational, population-based birth cohort studies (n = 45) in 23 low- and middle-income countries (LMICs) spanning 2000-2021.

POPULATION

Liveborn infants.

METHODS

Subnational, population-based studies with high-quality birth outcome data from LMICs were invited to join the Vulnerable Newborn Measurement Collaboration. We defined distinct newborn types using gestational age (preterm [PT], term [T]), birthweight for gestational age using INTERGROWTH-21st standards (small for gestational age [SGA], appropriate for gestational age [AGA] or large for gestational age [LGA]), and birthweight (low birthweight, LBW [<2500 g], nonLBW) as ten types (using all three outcomes), six types (by excluding the birthweight categorisation), and four types (by collapsing the AGA and LGA categories). We defined small types as those with at least one classification of LBW, PT or SGA. We presented study characteristics, participant characteristics, data missingness, and prevalence of newborn types by region and study.

RESULTS

Among 541 285 live births, 476 939 (88.1%) had non-missing and plausible values for gestational age, birthweight and sex required to construct the newborn types. The median prevalences of ten types across studies were T+AGA+nonLBW (58.0%), T+LGA+nonLBW (3.3%), T+AGA+LBW (0.5%), T+SGA+nonLBW (14.2%), T+SGA+LBW (7.1%), PT+LGA+nonLBW (1.6%), PT+LGA+LBW (0.2%), PT+AGA+nonLBW (3.7%), PT+AGA+LBW (3.6%) and PT+SGA+LBW (1.0%). The median prevalence of small types (six types, 37.6%) varied across studies and within regions and was higher in Southern Asia (52.4%) than in Sub-Saharan Africa (34.9%).

CONCLUSIONS

Further investigation is needed to describe the mortality risks associated with newborn types and understand the implications of this framework for local targeting of interventions to prevent adverse pregnancy outcomes in LMICs.

Calibration of the sub-aperture backscatter system on OMEGA EP

The sub-aperture backscatter (SABS) diagnostic on the OMEGA EP Laser System [Waxer et al., Opt. Photonics News 16, 30 (2005)] is a diagnostic that is used to measure the backscattered and sidescattered light during laser-plasma interaction experiments [W. L. Kruer, The Physics of Laser Plasma Interactions, Frontiers in Physics Vol. 73, edited by D. Pines (Addison-Wesley, Redwood City, CA, 1988) and Myatt et al., Phys. Plasmas 21, 055501 (2014)] that are relevant to high-energy-density physics and inertial confinement fusion. The diagnostic collects stimulated Brillouin scattering (SBS) UV light at around 351 nm and stimulated Raman scattering (SRS) in the visible-light regime in the 420-720-nm-wavelength range and provides spectrally and temporally resolved information. Five 1-in. light collectors, composed of a lens, ground glass diffuser, and coupling into a 300-μm fiber, are positioned behind the last steering mirror on one of the four beamlines to catch a portion of the beam cross section (∼1.5%) of the emission that is scattered into the beamline. The SRS light is collected in two light collectors, combined, and transported via graded index fibers to a streaked spectrometer. The SABS-SRS streak spectrometer has a temporal and spectral resolution of 100 ps and 1 nm, respectively. Three other light collectors collect, combine, and transport the SBS signal to a Hamamatsu high-voltage photodiode, where an oscilloscope digitizes the data, providing a time resolution of better than 1 ns. To obtain an absolute energy calibration of SRS measurements, light signals of known energy and wavelength were injected into the light collectors one at a time. The resulting counts on the streak camera charge-coupled device for SRS are then correlated with the incident fluence of scattered light at the light collector in order to allow a quantitative assessment of streak camera sensitivity to determine the energy of the scattered light during experiments. The measurements were performed in situ from the light collectors to the detectors. Additional offline measurements provided the transmission of the optics between the target chamber center and the light collectors.

Inverse Bremsstrahlung Absorption

Inverse bremsstrahlung absorption was measured based on transmission through a finite-length plasma that was thoroughly characterized using spatially resolved Thomson scattering. Expected absorption was then calculated using the diagnosed plasma conditions while varying the absorption model components. To match data, it is necessary to account for (i) the Langdon effect; (ii) laser-frequency (rather than plasma-frequency) dependence in the Coulomb logarithm, as is typical of bremsstrahlung theories but not transport theories; and (iii) a correction due to ion screening. Radiation-hydrodynamic simulations of inertial confinement fusion implosions have to date used a Coulomb logarithm from the transport literature and no screening correction. We anticipate that updating the model for collisional absorption will substantially revise our understanding of laser-target coupling for such implosions.

High Burden of Obesity and Low Rates of Weight Loss Pharmacotherapy in Inflammatory Bowel Disease: 10-Year Trend

Background

The prevalence of obesity and inflammatory bowel disease (IBD) has increased in the last decade. There is a paucity of data on the recent trend of obesity and the utilization of anti-obesity pharmacotherapy in IBD. We aimed to use a population-level database to analyze their trends.

Methods

A retrospective analysis of population-level data from 2010 to 2019 was performed among individuals ≥18 years of age using a commercial database, IBM Explorys. The prevalence and trends of obesity, diabetes mellitus type 2 (DM2), essential hypertension, dyslipidemia and/or hyperlipidemia, sleep apnea, and anti-obesity pharmacotherapy were studied. Univariate analysis using chi-square test and trend analysis using the Cochrane Armitage test were performed.

Results

Among 39 717 520 adults, 37.3% of IBD patients have a diagnosis of obesity (Crohn's disease 36.9% vs ulcerative colitis 38.5%, P < .0001). The proportion of IBD adults with obesity and metabolic comorbidities increased from 2010 to 2019: obesity (19.7%-30.1%), DM2 (8.3%-12.5%), hypertension (25.1%-33.9%), hyperlipidemia (22.1%-32.2%), and sleep apnea (4.1%-10.8%). All comparisons were statistically significant (P < .0001). Only 2.8% of eligible adults with obesity were prescribed anti-obesity pharmacotherapy in the last 10 years, with trends increasing from 1.4% to 3.6%, 2010-2019.

Conclusions

With obesity being a harbinger for metabolic syndrome, the increase in obesity in IBD patients was accompanied by a concomitant increase in the diseases associated with obesity in the past decade. However, this alarming rise in obesity was accompanied by a disproportionately small increase in anti-obesity pharmacotherapy similar to general population.

Role of through-the-scope catheter-based EUS in inflammatory bowel disease diagnosis and activity assessment

BACKGROUND AND AIMS

Distinguishing Crohn's disease (CD) from ulcerative colitis (UC) may be difficult when the disease is limited to the colon. Transmural healing is an important adjunctive measure of inflammatory bowel disease activity. The aim of this study was to examine the role of EUS in differentiating CD versus UC and evaluating transmural disease activity.

METHODS

This prospective cohort study enrolled 20 patients with CD (10 active [aCD], 10 inactive), 20 patients with UC (10 active [aUC], 10 inactive), and 20 control subjects who underwent colonoscopy from 2019 to 2021 at a tertiary care center. Measurements of bowel wall layer thickness from the rectum and cecum were obtained using a through-the-scope US catheter (UM-3R-3; Olympus, Center Valley, Penn, USA) at the time of colonoscopy.

RESULTS

Compared with control subjects, patients with aCD had thicker rectal submucosa and total wall layer (submucosa median, 1.80 mm [interquartile range {IQR}, 1.40-2.00] vs .60 mm [IQR, .40-.70]; total wall median, 3.70 mm [IQR, 3.52-4.62] vs 2.10 mm [IQR, 1.70-2.40], respectively; P < .01). Similar significant findings were observed for the cecal wall layers. Compared with control subjects, patients with aUC had thicker rectal mucosa and total wall but not submucosa or muscularis propria layers (mucosa median, 1.35 mm [IQR, 1.12-1.47] vs .60 mm [IQR, .57-.70]; total wall median, 3.45 mm [IQR, 2.85-3.75] vs 2.10 mm [IQR, 1.70-2.40], respectively; P < .01). Patients with aCD compared with those with aUC had a significantly thicker rectal submucosa layer (median, 1.80 mm [IQR, 1.40-2.00] vs .55 mm [IQR, .40-.75], respectively, P < .01). Cutoff values of 1.1 mm for rectal submucosa in CD (sensitivity, 1.0; specificity, 1.0) and 1.1 mm for rectal mucosa in UC (sensitivity, .8; specificity, .9) were found to differentiate active from inactive disease.

CONCLUSIONS

EUS measurements of colon wall layers can help diagnose aCD versus aUC and assess transmural disease activity. (Clinical trial registration number: NCT03863886.).

Measurement of laser absorption in underdense plasmas using near-field imaging of the incident and transmitted beams

Measurements of laser absorption in high-temperature, underdense plasmas produced at the Omega Laser Facility are made using two near-field imaging detectors that diagnose the spatial profile and energy of the port P9 beam before and after it transmits through the plasma. The incident beam is sampled using a partial reflection from a full-aperture, (30 cm-diam) uncoated wedge pickoff located before the target chamber vacuum window and final focus lens assembly. A concave mirror reduces the reflected beam size, allowing it to be recorded directly using a charged-coupled device (CCD) camera. The P9 transmitted beam diagnostic (P9TBD) characterizes the transmitted light by terminating the expanded beam on a semi-transparent diffuser and imaging the illuminated surface using a lens and CCD camera. The P9TBD samples a numerical aperture twice as large as the input beam, allowing the energy of transmitted beams with moderate levels of beam spray to be measured accurately. Calibration shots with no plasma provide a path to infer absorption without absolute photometric calibration of either detector. The cross-calibration between the two detectors was measured to remain stable at ±200 ppm, enabling measurements of total beam absorption below 1% with ±0.07% error.

Instrument design for an inertial confinement fusion ion temperature imager

A mix of contaminant mass is a known, performance-limiting factor for laser-driven inertial confinement fusion (ICF). It has also recently been shown that the contaminant mass is not necessarily in thermal equilibrium with the deuterium-tritium plasma [B. M. Haines et al., Nat. Commun. 11, 544 (2020)]. Contaminant mass temperature is one of the dominant uncertainties in contaminant mass estimates. The MixIT diagnostic is a new and potentially transformative diagnostic, capable of spatially resolving ion temperature. The approach combines principles of neutron time-of-flight and neutron imaging diagnostics. The information from the MixIT diagnostic can be used to optimize ICF target and laser drive designs as well as provide key constraints on ICF radiation-hydrodynamic simulations that are critical to contaminant mass estimates. This work details the design and optimization of the major components of the MixIT diagnostic: the neutron aperture, the neutron detector (scintillator), and the recording system.

Scattered-light uniformity imager for diagnosing laser absorption asymmetries on OMEGA

Light scattered from a target is the most-direct measurement for diagnosing laser absorption in a direct-drive implosion. Observations from OMEGA implosions show much larger scattered-light asymmetries than predictions. A new instrument has been developed to absolutely measure the scattered-light intensity and nonuniformity for the purpose of diagnosing the asymmetry. The scattered-light uniformity imager (SLUI) diagnostic records the variation in scattered-light intensity over a transmission diffuser using a charge-coupled device (CCD)/lens assembly. At the standard operating position, an 11.3° (f/2.5) cone of light is collected. A stray light baffle, debris shield, and antireflection absorbing filter are also incorporated into the diagnostic payload inserted into the target chamber. The imaging parts of the diagnostic (light baffle, vacuum window, filters, lens, and CCD camera) are located outside the target chamber. Five SLUIs have been built and deployed in OMEGA's ten-inch manipulator diagnostic ports, covering almost 5% of the emission surface, enabling an absolute scattered-light measurement should be within a few percent of the global average. Each SLUI system is calibrated offline, providing absolute scattered-light intensity measurements. Based on the measured point spread function, each diffuser plate image contains over 20 000 independent scattered-light absolute-intensity measurements of the variation over the collection cone. SLUI provides a platform to study scattered light and absorption asymmetries, and their possible sources.

The phase-2 particle x-ray temporal diagnostic for simultaneous measurement of multiple x-ray and nuclear emission histories from OMEGA implosions (invited)

Electron-temperature (T_e) measurements in implosions provide valuable diagnostic information, as T_e is negligibly affected by residual flows and other non-thermal effects unlike ion-temperature inferred from a fusion product spectrum. In OMEGA cryogenic implosions, measurement of T_e(t) can be used to investigate effects related to time-resolved hot-spot energy balance. The newly implemented phase-2 Particle X-ray Temporal Diagnostic (PXTD) utilizes four fast-rise (∼15 ps) scintillator-channels with distinct x-ray filtering. Titanium and stepped aluminum filtering were chosen to maximize detector sensitivity in the 10-20 keV range, as it has been shown that these x rays have similar density and temperature weighting to the emitted deuterium-tritium fusion neutrons (DTn) from OMEGA Cryo-DT implosions. High quality data have been collected from warm implosions at OMEGA. These data have been used to infer spatially integrated T_e(t) with <10% uncertainty at peak emission. Nuclear and x-ray emission histories are measured with 10 ps relative timing uncertainty for x rays and DTn and 12 ps for x rays and deuterium-He3 protons (D³Hep). A future upgrade to the system will enable spatially integrated T_e(t) with 40 ps time-resolution from cryogenic DT implosions.

Inflammatory Bowel Disease and Helicobacter pylori: Protective or Present?

This article describes the prevalence of inflammatory bowel disease in patients with gastritis, duodenitis, and peptic ulcer disease, stratified by Helicobacter pylori infection. Inflammatory boweld is less prevalent in patients with H. pylori, and no increased risk of IBD is seen after H. pylori eradication therapy.

Direct Measurement of the Return Current Instability in a Laser-Produced Plasma

Measurements were made of the return current instability growth rate, demonstrating its concurrence with nonlocal transport. Thomson scattering was used to measure a maximum growth rate of 5.1×10^{9}  Hz, which was 3 times less than classical Spitzer-Härm theory predicts. The measured plasma conditions indicate the heat flux was nonlocal, and Vlasov-Fokker-Planck simulations that account for nonlocality reproduce the measured growth rates. Furthermore, the threshold for the return current instability was measured (δ_{T}=0.017±0.002) to be in good agreement with previous theoretical models.

10-Year Trend of Abdominal Magnetic Resonance Imaging Compared With Abdominal Computed Tomography Scans in Inflammatory Bowel Disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) frequently undergo multiple computed tomography (CT) examinations. With the widespread availability of magnetic resonance imaging (MRI), it is unclear whether the use of CTs in IBD has declined. We aimed to analyze the trends of CT and MRI use in a large cohort of IBD patients in a 10-year period.

METHODS

We retrospectively analyzed adults ≥18 years of age using a de-identified database, IBM Explorys. Patients with ≥1 CT of the abdomen (± pelvis) or MRI of the abdomen (± pelvis) at least 30 days after the diagnosis of Crohn's disease (CD) or ulcerative colitis (UC) were included. We examined the factors associated with patients undergoing multiple CTs (≥5 CTs of the abdomen) and performed a trend analysis from 2010 to 2019.

RESULTS

Among 176 110 CD and 143 460 UC patients, those with ≥1 CT of the abdomen annually increased from 2010 to 2019 with mean annual percentage change of +3.6% for CD and +4.9% for UC. Similarly, annual percentage change for patients with ≥1 MRI (CD: +15.6%; UC: +22.8%) showed a rising trend. There was a 3.8% increase in CD patients receiving ≥5 CTs of the abdomen annually compared with a 2.4% increase among UC patients in the 10-year period. Age ≥50 years, men, African Americans, public insurance payors, body mass index ≥30kg/m2, and smoking history were associated with ≥5 CTs.

CONCLUSIONS

There is a considerable increase in the number of CT scans performed in IBD patients. Further studies can explore factors influencing the use of CT and MRI of the abdomen in IBD patients.

Rates of Intestinal Resection and Colectomy in Inflammatory Bowel Disease Patients After Initiation of Biologics: A Cohort Study

BACKGROUND & AIMS

50% to 80% Crohn's disease (CD) and 10% to 30% ulcerative colitis (UC) patients require surgery over their lifetime. Biologic therapies may alter this natural history, but data on the effect of biologics on surgery rates in this patient population are mixed. We sought to investigate the influence of biologics on surgery prevalence in CD and UC.

METHODS

We used a commercial database (Explorys Inc, Cleveland, OH), which includes electronic health record data from 26 major integrated US healthcare systems. We identified all patients who were diagnosed with CD or UC that were treated with any biologics between 2015 and 2020. The primary outcome was to examine the association between biologics therapy and the prevalence of bowel resection. Also, we identified the factors associated with surgery in IBD patients on biologics.

RESULTS

Of 32,904,480 patients in the database, we identified 140,540 patients with CD and 115,260 patients with UC, of whom 25,840 (18%) and 9,050 (7.8%) patients received biologics, respectively. The prevalence of intestinal resection was significantly lower in biologics-treated CD patients (9.3%) compared to those who did not receive biologics (12.1%) (p < .001). Similarly, biologic-treated UC patients were significantly less likely to undergo colectomy (7.3%) compared to UC patients who did not receive biologic therapy (11.0%) (p < .001). Tobacco use, Clostridium difficile infection, and perianal disease were associated with intestinal resection in CD. Colon neoplasm and Clostridium difficile infection were associated with colectomy in UC.

CONCLUSIONS

In this study of a large healthcare administrative database, inflammatory bowel disease (IBD) patients treated with biologics were significantly less likely to undergo bowel resection when compared to those who never received biologics. This data suggests that biologics may impact surgical rates in IBD.

Increased odds ratio for erectile dysfunction in COVID-19 patients

PURPOSE

Erectile dysfunction and COVID-19 share similar risk factors, including vascular disruption of integrity, cytokine release, cardiovascular disease, diabetes and obesity. The aim of this study was to investigate the association between erectile dysfunction and COVID-19 patients.

METHODS

Odds ratio for erectile dysfunction in patients with a history of COVID-19 with and without comorbidities were calculated using a patients' registry platform i2b2. ICD-10 diagnoses codes were accessed for queries and data were analyzed using logistic regression.

RESULTS

Patients with COVID-19 were 3.3 times more likely to have erectile dysfunction with 95% CI (2.8, 3.8). The association became stronger with odds ratio 4.8 (95% CI (4.1, 5.7)) after adjusting for age groups. The odds ratio remained the same after adjusting for smoking status with 3.5 (95% CI (3.0, 4.1)). After adjusting for race, COVID-19 patients were 2.6 (95% CI (2.2, 3.1)) times more likely to have erectile dysfunction. The odds ratio were 1.6, 1.8, 1.9 and 2.3 after adjusting for respiratory disease, obesity, circulatory disease and diabetes, respectively.

CONCLUSION

COVID-19 and erectile dysfunction are strongly associated even after adjustment for known risk factors and demographics.

Quantitative assessment of fitting errors associated with streak camera noise in Thomson scattering data analysis

Thomson scattering measurements in high energy density experiments are often recorded using optical streak cameras. In the low-signal regime, noise introduced by the streak camera can become an important and sometimes the dominant source of measurement uncertainty. In this paper, we present a formal method of accounting for the presence of streak camera noise in our measurements. We present a phenomenological description of the noise generation mechanisms and present a statistical model that may be used to construct the covariance matrix associated with a given measurement. This model is benchmarked against simulations of streak camera images. We demonstrate how this covariance may then be used to weight fitting of the data and provide quantitative assessments of the uncertainty in the fitting parameters determined by the best fit to the data and build confidence in the ability to make statistically significant measurements in the low-signal regime, where spatial correlations in the noise become apparent. These methods will have general applicability to other measurements made using optical streak cameras.

Novel design for a polarizing DUV spectrometer using a Wollaston prism and its application as a diagnostic for measuring Thomson scattering data in the presence of strong self-emission backgrounds

We present a novel design for an optical spectrometer for use in ultraviolet Thomson scattering measurements of plasma parameters in high energy density (HED) inertial confinement fusion experiments on large-scale high-energy laser facilities. In experiments investigating high-Z plasmas, the fidelity of measurements is commonly limited by signal/background ratios approaching or exceeding unity. An alpha barium borate Wollaston prism can provide both spectral dispersion and polarization channel separation, allowing simultaneous measurement of both the Thomson scattering signal and plasma self-emission along a single line of sight and in a single experiment, which should greatly improve data quality and reduce the opportunity cost of taking high quality measurements. We present a basic discussion of the design and a worked example of an instrument designed to take fourth harmonic electron plasma wave measurements in HED experiments at the OMEGA laser facility.

Nonuniform Absorption and Scattered Light in Direct-Drive Implosions Driven by Polarization Smoothing

Laser-direct-drive symmetric implosions on OMEGA illuminate a target with 60 laser beams and are designed to produce spherical implosions. Each beam is smoothed using orthogonal polarizations obtained by passing the laser beams through distributed polarization rotators (DPRs). Observations of light scattered from OMEGA implosions do not show the expected symmetry and have much larger variation than standard predictions. For the first time, we have quantified the scattered-light nonuniformity from individual beams and identified the DPRs as the source of the enhanced nonuniformity. An instrument was invented that isolated and measured the variation in the intensity and polarization of the light scattered from each OMEGA beam. The asymmetric intensity and polarization measurements are explained when the on-target offsets between the two orthogonal polarizations produced by the DPRs are modeled using a 3D cross-beam energy transfer (CBET) code that tracks the polarizations of each beam. The time-integrated nonuniformity in laser absorption and scattered light due to CBET and the DPR polarization offsets during high-performance OMEGA implosions is predicted to be significant and dominated by low spherical harmonic mode numbers. The nonuniformity is predicted to be greatly reduced by replacing the DPRs with new optics that create smaller offsets.

Measurements of Non-Maxwellian Electron Distribution Functions and Their Effect on Laser Heating

Electron velocity distribution functions driven by inverse bremsstrahlung heating are measured to be non-Maxwellian using a novel angularly resolved Thomson-scattering instrument and the corresponding reduction of electrons at slow velocities results in a ∼40% measured reduction in inverse bremsstrahlung absorption. The distribution functions are measured to be super-Gaussian in the bulk (v/v_{th}<3) and Maxwellian in the tail (v/v_{th}>3) when the laser heating rate dominates over the electron-electron thermalization rate. Simulations with the particle code quartz show the shape of the tail is dictated by the uniformity of the laser heating.

Evaluation of a Hyperbaric Oxygen Therapy Intervention in Individuals with Fibromyalgia

OBJECTIVE

To evaluate the feasibility and safety of hyperbaric oxygen therapy (HBOT) in patients with fibromyalgia (FM).

DESIGN

A cohort study with a delayed treatment arm used as a comparator.

SETTING

Hyperbaric Medicine Unit, Toronto General Hospital, Ontario, Canada.

SUBJECTS

Eighteen patients diagnosed with FM according to the American College of Rheumatology and a score ≥60 on the Revised Fibromyalgia Impact Questionnaire.

METHODS

Participants were randomized to receive immediate HBOT intervention (n = 9) or HBOT after a 12-week waiting period (n = 9). HBOT was delivered at 100% oxygen at 2.0 atmospheres per session, 5 days per week, for 8 weeks. Safety was evaluated by the frequency and severity of adverse effects reported by patients. Feasibility was assessed by recruitment, retention, and HBOT compliance rates. Both groups were assessed at baseline, after HBOT intervention, and at 3 months' follow-up. Validated assessment tools were used to evaluate pain, psychological variables, fatigue, and sleep quality.

RESULTS

A total of 17 patients completed the study. One patient withdrew after randomization. HBOT-related adverse events included mild middle-ear barotrauma in three patients and new-onset myopia in four patients. The efficacy of HBOT was evident in most of the outcomes in both groups. This improvement was sustained at 3-month follow-up assessment.

CONCLUSION

HBOT appears to be feasible and safe for individuals with FM. It is also associated with improved global functioning, reduced symptoms of anxiety and depression, and improved quality of sleep that was sustained at 3-month follow-up assessment.

Unabsorbed light beamlets for diagnosing coronal density profiles and absorption nonuniformity in direct-drive implosions on OMEGA

Laser light scattered from a target is the most-direct measurement for diagnosing laser absorption in a direct-drive implosion. The 3ω gated optical imager beamlets diagnostic images unabsorbed light from all 60 OMEGA beams as distinct "beamlet" spots for each beam. The implosion can be diagnosed using the position and intensity of these beamlets. The position of each beamlet in the image is determined by refraction and can be used to fit the coronal plasma density profile of the implosion. The inferred plasma density profiles are comparable to the profiles predicted by the 1D hydrodynamics code LILAC but suggest that the predictions underestimate the density farther out in the corona. The intensity of light in each spot depends on the cumulative effects of absorption and cross-beam energy transfer along the beamlet's path through the corona. The measured variation in intensity and polarization between similar spots indicates that absorption during OMEGA implosions is less uniform than previously known.

Whole-genome sequencing of African Americans implicates differential genetic architecture in inflammatory bowel disease

Whether or not populations diverge with respect to the genetic contribution to risk of specific complex diseases is relevant to understanding the evolution of susceptibility and origins of health disparities. Here, we describe a large-scale whole-genome sequencing study of inflammatory bowel disease encompassing 1,774 affected individuals and 1,644 healthy control Americans with African ancestry (African Americans). Although no new loci for inflammatory bowel disease are discovered at genome-wide significance levels, we identify numerous instances of differential effect sizes in combination with divergent allele frequencies. For example, the major effect at PTGER4 fine maps to a single credible interval of 22 SNPs corresponding to one of four independent associations at the locus in European ancestry individuals but with an elevated odds ratio for Crohn disease in African Americans. A rare variant aggregate analysis implicates Ca²⁺-binding neuro-immunomodulator CALB2 in ulcerative colitis. Highly significant overall overlap of common variant risk for inflammatory bowel disease susceptibility between individuals with African and European ancestries was observed, with 41 of 241 previously known lead variants replicated and overall correlations in effect sizes of 0.68 for combined inflammatory bowel disease. Nevertheless, subtle differences influence the performance of polygenic risk scores, and we show that ancestry-appropriate weights significantly improve polygenic prediction in the highest percentiles of risk. The median amount of variance explained per locus remains the same in African and European cohorts, providing evidence for compensation of effect sizes as allele frequencies diverge, as expected under a highly polygenic model of disease.

A transmitted-beam diagnostic for the wavelength-tunable UV drive beam on OMEGA

A transmitted-beam diagnostic (P9TBD) was developed as part of a new experimental platform used to study laser-plasma interactions on OMEGA. Located in the opposing port to the wavelength-tunable (350 nm to 353 nm) UV drive beam, the P9TBD characterizes the beam after it propagates through an undersense plasma. The instrument consists of a large-aperture window that allows light to exit the target chamber and project onto a thin sheet of semi-transparent diffuser material. Light transmitted through the diffuser is recorded using a time-integrated camera and a fiber-optically coupled streaked spectrometer, providing measurements of the energy, power, fluence, polarization, and spectrum of the transmitted beam. The diagnostic enables direct observation of a variety of cross-beam energy transfer phenomena, such as wavelength detuning, polarization effects, and gain saturation.

Cross-Beam Energy Transfer Saturation by Ion Heating

We measure cross-beam energy transfer (CBET) saturation by ion heating in a gas-jet plasma characterized using Thomson scattering. A wavelength-tunable ultraviolet (UV) probe laser beam interacts with four intense UV pump beams to drive large-amplitude ion-acoustic waves. For the highest-intensity interactions, the power transfer to the probe laser drops, demonstrating ion-acoustic wave saturation. Over this time, the ion temperature is measured to increase by a factor of 7 during the 500-ps interaction. Particle-in-cell simulations show ion trapping and a subsequent ion heating consistent with measurements. Linear kinetic CBET models are found to agree well with the observed energy transfer when the measured plasma conditions are used.

A multi-channel x-ray temporal diagnostic for measurement of time-resolved electron temperature in cryogenic deuterium-tritium implosions at OMEGA

Electron-temperature (T_e) measurements in implosions provide valuable diagnostic information, as T_e is unaffected by residual flows and other non-thermal effects unlike ion temperature inferred from a fusion product spectrum. In OMEGA cryogenic implosions, measurement of T_e(t) can be used to investigate effects related to time-resolved hot-spot energy balance. The proposed diagnostic utilizes five fast-rise (∼15 ps) scintillator channels with distinct x-ray filtering. Titanium and stepped aluminum filtering were chosen to maximize detector sensitivity in the 10 keV-20 keV range, as it has been shown that these x rays have similar density and temperature weighting to the emitted deuterium-tritium fusion neutrons. Initial data collected using a prototype nosecone on the existing neutron temporal diagnostic demonstrate the validity of this diagnostic technique. The proposed system will be capable of measuring spatially integrated T_e(t) with 20 ps time resolution and <10% uncertainty at peak emission in cryogenic DT implosions.

Using millimeter-sized carbon-deuterium foils for high-precision deuterium-tritium neutron spectrum measurements in direct-drive inertial confinement fusion at the OMEGA laser facility

Millimeter-sized CD foils fielded close (order mm) to inertial confinement fusion (ICF) implosions have been proposed as a game-changer for improving energy resolution and allowing time-resolution in neutron spectrum measurements using the magnetic recoil technique. This paper presents results from initial experiments testing this concept for direct drive ICF at the OMEGA Laser Facility. While the foils are shown to produce reasonable signals, inferred spectral broadening is seen to be high (∼5 keV) and signal levels are low (by ∼20%) compared to expectation. Before this type of foil is used for precision experiments, the foil mount must be improved, oxygen uptake in the foils must be better characterized, and impact of uncontrolled foil motion prior to detection must be investigated.

Evaluating a Standardized Transition of Care Process for Pediatric Inflammatory Bowel Disease Patients

To reduce lapses in care for pediatric inflammatory bowel disease (IBD) patients approaching adulthood, a health maintenance transition visit (HMV) was developed to supplement standard medical care (SMV). Our aim was to assess the effect of the HMV on transition readiness. A retrospective chart review was conducted at a single center with demographics and clinical data from HMV and SMV visits. Effectiveness of the HMV was assessed by the patient health questionanaire-9 (PHQ-9) and transition readiness assessment questionnaire (TRAQ) scores. A total of 140 patients, 80% Caucasian and 59% male completed an HMV. The mean age was 18 ± 2 years old, and 93% of patients reported inactive or mild disease. Patients who completed at least 1 prior HMV scored significantly higher on the TRAQ when transferring to adult care compared to patients transferred at their first HMV visit (92 vs. 83, p < 0.05). Of patients with no prior depression diagnosis, 36% had a positive screen for depression. A significant relationship was identified between disease status and PHQ-9 (p < 0.05). This study demonstrated a structured HMV increased transition readiness and quantified the significant under-diagnosis of depression in this population, emphasizing the importance of screening. These results indicate depression may affect patients' transition preparedness.

Requirements for a 4ω Thomson scattering system on megajoule scale laser facilities

With the arrival of megajoule class laser facilities, the features of laser-produced plasmas are evolving toward unprecedented high electron temperatures reached in the environment of a cm-scale indirect-drive Hohlraum for a few tens of nanoseconds. In this context, the need for in situ experimental characterization of the plasma parameters becomes critical in order to test hydrodynamics simulations in these novel conditions. Taking advantage of the progress achieved in the last 40 years, Thomson scattering has become a classic diagnostic in the characterization of laser produced plasmas. However, the many beam configuration of the megajoule scale experiments makes the measurements increasingly complex because the Thomson scattering signals produced by the 351 nm heaters themselves dominate the plasma emission around 263 nm, a wavelength range typically of interest when a 4ω Thomson probe is used. This paper reviews the requirements for and the potential of a 4ω Thomson scattering system to be operated on such 351 nm megajoule scale facilities in order to characterize the hot (T_e > 3 keV) plasmas produced in the indirect-drive irradiation of a Hohlraum. It is found that the configuration of the diagnostic could be optimized in order to enable the detection of the ion acoustic resonances over a large domain of plasma parameters. The results for the electron plasma wave resonances are also given.

Visual Function and Visual Acuity in An Urban Adult Population

In this survey, 6,850 Baltimore residents aged 40 and older were interviewed about activities they had difficulty doing or could no longer do because of poor vision. One-fourth of the sample reported limitations in activities, most frequently reading and other near-vision tasks, because of poor vision. In addition to poor vision, general health status, educational level, and time since the last eye care visit were associated with the loss of visual function.

OP0071 PREDICTING PERSISTENT HIGH-DOSE OPIOID USE AFTER TOTAL KNEE REPLACEMENT

Background:

Patients undergoing total knee replacement (TKR) are at increased risk of persistent opioid use and dependence

Objectives:

To identify patients with persistent high-dose opioid use after TKR using group-based trajectory models (GBTM) and determine predictors of persistent high-dose opioid users using pre-TKR patient characteristics

Methods:

Using US Medicare claims (2010-2014), we identified patients aged ≥65 years who underwent a TKR and had no history of cancer or high-dose opioid use (>25 mean morphine equivalents (MME)/day) in the year prior. All patients were continuously enrolled in Medicare for ≥360 days prior to and ≥30 days after the TKR. To determine opioid filling patterns after the surgery, patients were followed up to 360 days from the day of TKR. We modeled 12 monthly indicators of opioid prescription fills as a continuous (MME/day) variable using a censored normal GBTM and categorized patients into 4 groups. The primary outcome was persistent high-dose opioid use defined as patients in trajectory Group 3 (38.8 MME/day) or Group 4 (22.4 MME/day). We split the data into training (2010-2013 data) and test (2014 data) sets and used logistic regression to predict high-dose opioid use vs low-dose opioid use (Groups 1 and 2) as a binary outcome utilizing pre-TKR patient characteristics as candidate predictors using the least absolute shrinkage and selection operator (LASSO) regression for variable selection. A reduced model with only 10 pre-specified variables readily available for clinical use was also considered

Results:

The final study cohort included 142,089 patients. The GBTM identified 4 distinct trajectories (Group 1- Short-term, low-dose, Group 2- long-term, low-dose, Group 3- medium-term, high-dose, Group 4-long-term, high-dose) of opioid use in the year after TKR(Figure). Using logistic regression and LASSO, we predicted the probability of persistent high-dose opioid use (N=17,171) (vs. low-dose opioid use) in the training set (N=101,810) for an AUC=0.80. The AUC in the test set (N=40,279) predicting high opioid use (N=5,893) was 0.77. The final model selected 33 variables and identified baseline history of opioid use as the strongest positive predictor of high-dose persistent opioid use. The reduced model with only ten predictors also performed equally well (AUC=0.77)(Table).

Conclusion:

In this cohort of older patients with no history of cancer or high-dose opioid use at baseline, 16.2% became high dose (28.1 MME/day) opioid users during the year after TKR. Our prediction model with 10 readily available clinical factors may help identify patients at high risk of future adverse outcomes from persistent opioid use and dependence after TKR

Figure.

 Trajectories of opioid use patterns after TKR

Table.

Predictors of persistent high-dose opioid use in the reduced mode

VariableMultivariable Odds Ratio (95% CI)Predicting High dose vs.Low dose opioid useP-valueAge (in years)0.94 (0.93-0.94)<0.001Females (Ref=Males)0.99 (0.93-1.06)0.78White race (Ref=Other)1.25 (1.04-1.50)0.02Baseline opioid use (MME/day)1.22 (1.22-1.23)<0.001Substance use (Yes/No)1.10 (1.02-1.20)0.02Benzodiazepine use (Yes/No)1.22 (1.12-1.32)<0.001Anxiolytic use (Yes/No)1.30 (1.19-1.43)<0.001Anticonvulsant use (Yes/No)0.94 (0.87-1.03)0.19Antidepressant use (Yes/No)1.03 (0.96-1.11)0.36NSAID use (Yes/No)1.07 (1.00-1.14)0.04

Disclosure of Interests:

Chandrasekar Gopalakrishnan: None declared, Jessica Franklin: None declared, Yinzhu Jin: None declared, Daniel Solomon Grant/research support from: Funding from Abbvie and Amgen unrelated to this work, Jeffrey Katz Grant/research support from: Dr Katz reported receiving grants from Samumed and Flexion Therapeutics outside the submitted work., Yvonne Lee Shareholder of: Cigna-Express Scripts, Grant/research support from: Pfizer, Consultant of: Highland Instruments, Inc., Patricia Franklin: None declared, Joyce Lii: None declared, Rishi J Desai Grant/research support from: Dr. Desai reported receiving grants from Bayer, Novartis, and Vertex Pharmaceuticals outside the submitted work., Seoyoung Kim Grant/research support from: Seoyoung C Kim has received research grants from AbbVie, Roche, Bristol-Myers Squibb and Pfizer.

Measurement of Kinetic-Scale Current Filamentation Dynamics and Associated Magnetic Fields in Interpenetrating Plasmas

We present the first local, quantitative measurements of ion current filamentation and magnetic field amplification in interpenetrating plasmas, characterizing the dynamics of the ion Weibel instability. The interaction of a pair of laser-generated, counterpropagating, collisionless, supersonic plasma flows is probed using optical Thomson scattering (TS). Analysis of the TS ion-feature revealed anticorrelated modulations in the density of the two ion streams at the spatial scale of the ion skin depth c/ω_{pi}=120  μm, and a correlated modulation in the plasma current. The inferred current profile implies a magnetic field amplitude ∼30±6  T, corresponding to ∼1% of the flow kinetic energy, indicating that magnetic trapping is the dominant saturation mechanism.

Plasma Collision in a Gas Atmosphere

We present a study on the impact of a gas atmosphere on the collision of two counterpropagating plasmas (gold and carbon). Imaging optical Thomson scattering data of the plasma collision with and without helium in between have been obtained at the Omega laser facility. Without gas, we observed large scale mixing of colliding gold and carbon ions. Once ambient helium is added, the two plasmas remain separated. The difference in ionic temperature is consistent with a reduction of the maximum Mach number of the flow from M=7 to M=4. It results in a reduction of a factor ∼10 of the counterstreaming ion-ion mean free path. By adding a low-density ambient gas, it is possible to control the collision of two high-velocity counterstreaming plasma, transitioning from an interpenetrating regime to a regime in agreement with a hydrodynamic description.

Evolution of the Electron Distribution Function in the Presence of Inverse Bremsstrahlung Heating and Collisional Ionization

The picosecond evolution of non-Maxwellian electron distribution functions was measured in a laser-produced plasma using collective electron plasma wave Thomson scattering. During the laser heating, the distribution was measured to be approximately super-Gaussian due to inverse bremsstrahlung heating. After the heating laser turned off, collisional ionization caused further modification to the distribution function while increasing electron density and decreasing temperature. Electron distribution functions were determined using Vlasov-Fokker-Planck simulations including atomic kinetics.

Predictors of Post-operative Pain and Opioid Consumption in Patients Undergoing Liver Surgery

BACKGROUND

Post-operative pain management is a critical component of perioperative care. Patients at risk of poorly controlled post-operative pain may benefit from early measures to optimize pain management. We sought to identify risk factors for post-operative pain and opioid consumption in patients undergoing liver resection.

METHODS

This is a multi-institutional prospective nested cohort study of patients undergoing open liver resection. Opioid consumption and pain scores were collected following surgery. To estimate the effects of patient factors on opioid consumption (oral morphine equivalents-OME) and on pain scores (NRS-11), we used generalized linear models and multivariable linear regression model, respectively.

RESULTS

One hundred and fifty-three patients who underwent open liver resection between 2013 and 2016 were included in the study. The mean patient age was 62.2 years, and 43.3% were female. Younger patients were significantly more likely to use more opioids in the early post-operative period (16.7 OME/10 years, p < 0.001). Patient factors that were significantly associated with increased NRS-11 pain scores also included younger patient age (difference in pain score of 0.3/10 years with cough and 0.2/10 years at rest, p < 0.01 for both) as well as a history of analgesic use (difference in pain score of 0.9 with cough and 0.6 at rest, p < 0.01 and p = 0.07, respectively).

CONCLUSION

Younger patients and those with a history of analgesic use are more likely to report higher post-operative pain and require higher doses of opioids. Early identification of these patients, and measures to better manage their pain, may contribute to optimal perioperative care.

Informed Consent in IBD Trials: Where We Are and Where We Need to Go

Patient enrollment is increasingly recognized as a major limiting factor to inflammatory bowel disease (IBD) clinical trial completion. Many IBD trials will fail to enroll enough patients to adequately power their study. This has led to a renewed multifaceted effort to encourage more patients to enroll in clinical trials. Although this is of clear importance, it is also important to ensure that all efforts to enroll patients in clinical trials do not compromise the quality and validity of the patient's/study participant's informed consent. Informed consent has 4 components: disclosure, voluntariness, understanding, and capacity. The application of informed consent to IBD clinical trials for biologic agents has not been previously studied. Yet the nature of clinical trials for biologics in IBD creates certain challenges to properly fulfilling the requirements of informed consent in the recruitment process that should be examined. In the following commentary, the components of informed consent are reviewed, challenges to their fulfillment in IBD trials are reviewed, and practical advice is offered.

Risk of Myocardial Infarction in Inflammatory Bowel Disease: A Population-based National Study

BACKGROUND & OBJECTIVE

Chronic inflammation is linked to increased cardiovascular risk. Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the gastrointestinal tract and elevated pro-inflammatory markers. The association between IBD and myocardial infarction (MI) is not well understood. We sought to elucidate this risk using a large database.

METHODS

We reviewed data from a large commercial database (Explorys, IBM Watson) that aggregates electronic medical records from 26 nationwide health care systems. Using systemized nomenclature of medicine-clinical terms, we identified adult patients (20 to 65 years) with a diagnosis of IBD-ulcerative colitis (UC) or Crohn's disease (CD)-who had active records between August 2013 and August 2018. We then examined the risk of MI in patients with or without IBD.

RESULTS

Out of 29,090,220 patients, 131,680 (0.45%) had UC, and 158,750 (0.55%) had CD. Prevalence of MI was higher in patients with UC and CD versus non-IBD patients (UC 6.7% vs CD 8.8% vs non-IBD 3.3%, odds ratio [OR] for UC 2.09 [2.04 -2.13], and CD 2.79 [2.74-2.85]. The odds of MI in IBD patients overall were highest in younger patients and decreased with age (age 30-34 years: OR 12.05 [11.16-13.01], age 65+ years: OR 2.08 [2.04-2.11]). After adjusting for age, race, sex, and traditional cardiovascular risk factor, IBD conferred greater odds of MI (adjusted odds ratio [aOR] 1.25 [1.24-1.27]).

CONCLUSION

In this large cohort, IBD is associated with significantly increased MI compared with non-IBD patients. The relative risk of MI was highest in younger patients and decreased with age. These findings emphasize the need for aggressive risk factor reduction in IBD.