Simplified processing and rapid quantification of buprenorphine, norbuprenorphine, and their conjugated metabolites in human plasma using UPLC-MS/MS: Assessment of buprenorphine exposure during opioid use disorder treatment

Opioid use disorder (OUD) is a chronic neurobehavioral ailment and is prevalent in pregnancy. OUD is commonly treated with methadone or buprenorphine (BUP). Pregnancy is known to alter the pharmacokinetics of drugs and may lead to changes in drug exposure and response. A simple, specific, and sensitive analytical method for measuring the parent drug and its metabolites is valuable for assessing the impact of pregnancy on drug exposure. A new liquid chromatography-tandem mass spectrometric method that utilized a simple protein precipitation procedure for sample preparation and four deuterated internal standards for quantification was developed and validated for BUP and its major metabolites (norbuprenorphine [NBUP], buprenorphine-glucuronide [BUP-G], and norbuprenorphine-glucuronide [NBUP-G]) in human plasma. The standard curve was linear over the concentration range of 0.05-100 ng/mL for BUP and NBUP, and 0.1-200 ng/mL for BUP-G and NBUP-G. Intra- and inter-day bias and precision were within ±15% of nominal values for all the analytes. Quality controls assessed at four levels showed high recovery consistently for all the analytes with minimal matrix effect. Adequate analyte stability was observed at various laboratory conditions tested. Overall, the developed method is simple, sensitive, accurate and reproducible, and was successfully applied for the quantification of BUP and its metabolites in plasma samples collected from pregnant women in a clinical study assessing BUP exposure during OUD treatment.

Renal dysfunction in routine proton-pump inhibitor use may be linked to comorbidities: A real-world observational study

INTRODUCTION

The use of proton-pump inhibitors (PPI) is linked with infrequent but serious adverse events, including acute kidney injury, chronic kidney disease (CKD) and progression of CKD. Data on renal safety in routine use of PPI are more relevant to clinical practice. We studied whether such use of PPI is associated with renal dysfunction.

METHODS

Patients taking PPI for at least six weeks had serum creatinine tested pre (n = 200) and post (n = 180) recruitment. These patients were then advised to follow-up: those taking PPI for at least 90 days in the next six months (n = 77) and at least another 90 days in the following six months (n = 50), had serum creatinine tested at such follow-up. Renal dysfunction was defined as any increase in serum creatinine level above baseline.

RESULTS

The 200 patients recruited had mean age 39.6 (SD 9.2) years. Ninety-eight (49%) patients had a history of previous PPI use (median six months; interquartile range [IQR] 3-24). Only 20 (11.1%) patients at six weeks, 11 (14.3%) at six months and six (12%) at one year had increase in creatinine level; a majority of them had less than 0.3 mg/dL increase. Ten of these 20 (six weeks), five of 11 (six months) and five of six (one year) had other risk factors for renal dysfunction. No patient developed CKD during the study period.

CONCLUSIONS

Mild and non-progressive increase in serum creatinine occurred in 10% to 15% of patients on routine PPI use. A majority of them had other risk factors. Small sample size and short follow-up duration are a few limitations of this study.

Effective connectivity relates seizure outcome to electrode placement in responsive neurostimulation

Responsive neurostimulation is a closed-loop neuromodulation therapy for drug resistant focal epilepsy. Responsive neurostimulation electrodes are placed near ictal onset zones so as to enable detection of epileptiform activity and deliver electrical stimulation. There is no standard approach for determining the optimal placement of responsive neurostimulation electrodes. Clinicians make this determination based on presurgical tests, such as MRI, EEG, magnetoencephalography, ictal single-photon emission computed tomography and intracranial EEG. Currently functional connectivity measures are not being used in determining the placement of responsive neurostimulation electrodes. Cortico-cortical evoked potentials are a measure of effective functional connectivity. Cortico-cortical evoked potentials are generated by direct single-pulse electrical stimulation and can be used to investigate cortico-cortical connections in vivo. We hypothesized that the presence of high amplitude cortico-cortical evoked potentials, recorded during intracranial EEG monitoring, near the eventual responsive neurostimulation contact sites is predictive of better outcomes from its therapy. We retrospectively reviewed 12 patients in whom cortico-cortical evoked potentials were obtained during stereoelectroencephalography evaluation and subsequently underwent responsive neurostimulation therapy. We studied the relationship between cortico-cortical evoked potentials, the eventual responsive neurostimulation electrode locations and seizure reduction. Directional connectivity indicated by cortico-cortical evoked potentials can categorize stereoelectroencephalography electrodes as either receiver nodes/in-degree (an area of greater inward connectivity) or projection nodes/out-degree (greater outward connectivity). The follow-up period for seizure reduction ranged from 1.3-4.8 years (median 2.7) after responsive neurostimulation therapy started. Stereoelectroencephalography electrodes closest to the eventual responsive neurostimulation contact site tended to show larger in-degree cortico-cortical evoked potentials, especially for the early latency cortico-cortical evoked potentials period (10-60 ms period) in six out of 12 patients. Stereoelectroencephalography electrodes closest to the responsive neurostimulation contacts (≤5 mm) also had greater significant out-degree in the early cortico-cortical evoked potentials latency period than those further away (≥10 mm) (P < 0.05). Additionally, significant correlation was noted between in-degree cortico-cortical evoked potentials and greater seizure reduction with responsive neurostimulation therapy at its most effective period (P < 0.05). These findings suggest that functional connectivity determined by cortico-cortical evoked potentials may provide additional information that could help guide the optimal placement of responsive neurostimulation electrodes.

Self-reported food intolerances in an Indian population: Need for individualization rather than a universal low-FODMAP diet

Background and Aim

Low-fermentable oligo-, di-, and monosaccharides and polyol (FODMAP) diets have been recommended for individuals with food intolerance and irritable bowel syndrome (IBS). Individual food intolerances may, however, not correspond to the FODMAP content alone.

Methods

We conducted a survey on self-reported intolerance to articles of food commonly identified as high FODMAP in 400 healthy Indian subjects (median age 40 years; 69% men) and 204 consecutive consenting patients with IBS (median age 36 years; 58% men).

Results

One-hundred seventy-nine (44.8%) healthy subjects and 147 (72.1%) patients with IBS reported some food intolerance (P < 0.00001); the latter reported intolerance to all items (except nuts) more frequently than healthy subjects. The prevalence, however, varied from 2.5 to 32%. Milk intolerance was reported equally commonly by healthy subjects and patients (23% vs 29.9%). Twenty-three (11.3%) patients and no healthy subjects reported wheat sensitivity. The IBS diarrhea subgroup reported intolerance to milk, pulses, capsicum, cauliflower, leafy vegetables, and dry fruits more frequently than the constipation subgroup.

Conclusion

From among a list of high-FODMAP items, individuals' intolerance varied widely, suggesting that individuals should be the final judge in deciding their elimination diets rather than devise them based on the FODMAP content alone. As in the West, food intolerance was reported more commonly by patients with IBS, especially those with diarrhea, than by healthy individuals. Also noteworthy is the low prevalence of milk intolerance in a subcontinent labeled as high in lactose intolerance. Unlike in the West, wheat intolerance was not reported by any healthy individual.

Prospective Comparative Study of Quality of Life in Bladder Cancer Patients Undergoing Cystectomy or Bladder Preservation

PURPOSE/OBJECTIVE(S)

Health-related Quality of life (HRQOL) may be decisive when different treatments yield comparable survival outcomes. We compared QOL in patients undergoing radical cystectomy with ileal conduit (RCIC) or bladder preservation (BP) with (chemo)radiotherapy for bladder cancer.

MATERIALS/METHODS

Patients with histological diagnosis of bladder cancer, stage T1-T4, N0-N1, M0 with a minimum follow-up of 6 months from the last treatment intervention (RCIC or BP) and alive without disease at the time of QOL assessment were eligible for inclusion. After ethics committee approval, two HRQOL instruments were translated, validated and administered: Bladder cancer index (BCI) for bladder cancer-specific HRQOL, which includes 36 items under three domains - bladder, bowel and sexual function and the EORTC QLQ C30 which includes 30 items under three domains - functional, symptom and global health. The mean QOL scores across various domains and specific questions were compared between the two treatment groups using the independent t-test.

RESULTS

Of the 104 patients enrolled, 56 had RCIC, and 48 received BP, and included 95 (91.3%) males. The median time from treatment completion to QOL assessment was 22 months (IQR 10-56). The median age for the entire cohort was 62 years (IQR 55-68), 65.5 years (IQR 55-71) in BP and 59.5 years (IQR 55-66) in RCIC. Overall, mean BCI urinary scores and bowel scores were high in both groups, with no significant difference in function or bother subdomains between the two groups (Table 1). Overall, BCI sexual scores were low in both the groups but significantly better after BP (BPmean 56.9, RCICmean 41.5, p = 0.01). Mean scores for sexual function BPmean 38.4 and RCIC mean 25 p (0.07) and sexual bother BPmean 81 RCICmean 62 (p 0.02) subdomains. There was no significant difference in EORTC QOL outcomes in functional (BPmean 91.4, RCICmean 88.7 p 0.23), symptom (BPmean 89.8, RCICmean 89, p = 0.68) and global health scale (BPmean 76.8, RCICmean 78.5, p = 0.69) in both groups. On question-wise assessment, the ability to perform an exercise (BPmean 94.2, RCICmean 85, p = 0.06) and urinary leakage at night time (BPmean 91.7, RCICmean 77.6, p = 0.01) were better in the BP group, while scores for blood in the urine (BPmean 89.1, RCICmean 97, p = 0.05) were better in the RCIC group compared to BP.

CONCLUSION

Overall, QOL was good in both groups in the urinary and bowel domains while it was low in the sexual domain. However, bladder preservation performed significantly better in the sexual domain than RCIC.

Study Protocol of the Bladder Adjuvant RadioTherapy (BART) Trial: A Randomised Phase III Trial of Adjuvant Radiotherapy Following Cystectomy in Bladder Cancer

AIMS

To assess the efficacy and safety of adjuvant radiotherapy in patients with high-risk muscle-invasive bladder cancer (MIBC) following radical cystectomy (RC) and chemotherapy.

MATERIALS AND METHODS

The BART (Bladder Adjuvant RadioTherapy) trial is an ongoing multicentric, randomised, phase III trial comparing the efficacy and safety of adjuvant radiotherapy versus observation in patients with high-risk MIBC. The key eligibility criteria include ≥pT3, node-positive (pN+), positive margins and/or nodal yield <10, or, neoadjuvant chemotherapy for cT3/T4/N+ disease. In total, 153 patients will be accrued and randomised, in a 1:1 ratio, to either observation (standard arm) or adjuvant radiotherapy (test arm) following surgery and chemotherapy. Stratification parameters include nodal status (N+ versus N0) and chemotherapy (neoadjuvant chemotherapy versus adjuvant chemotherapy versus no chemotherapy). For patients in the test arm, adjuvant radiotherapy to cystectomy bed and pelvic nodes is planned with intensity-modulated radiotherapy to a dose of 50.4 Gy in 28 fractions using daily image guidance. All patients will follow-up with 3-monthly clinical review and urine cytology for 2 years and subsequently 6 monthly until 5 years, with contrast-enhanced computed tomography abdomen pelvis 6 monthly for 2 years and annually until 5 years. Physician-scored toxicity using Common Terminology Criteria for Adverse Events version 5.0 and patient-reported quality of life using the Functional Assessment of Cancer Therapy - Colorectal questionnaire is recorded pre-treatment and at follow-up.

ENDPOINTS AND STATISTICS

The primary endpoint is 2-year locoregional recurrence-free survival. The sample size calculation was based on the estimated improvement in 2-year locoregional recurrence-free survival from 70% in the standard arm to 85% in the test arm (hazard ratio 0.45) using 80% statistical power and a two-sided alpha error of 0.05. Secondary endpoints include disease-free survival, overall survival, acute and late toxicity, patterns of failure and quality of life.

CONCLUSION

The BART trial aims to evaluate whether contemporary radiotherapy after standard-of-care surgery and chemotherapy reduces pelvic recurrences safely and also potentially affects survival in high-risk MIBC.

THE GUT-BRAIN AXIS: IMPLICATIONS FOR NEUROLOGICAL DISORDERS, MENTAL HEALTH, AND IMMUNE FUNCTION

A gut-brain axis (GBA) has a long history of conceptual development. Intestinal dysbiosis has now been recognized as a key player in the development of adult neurodevelopmental disorders, obesity, and inflammatory bowel disease. Recent developments in metagenomics suggest those nutrition and gut microbiotas (GM) are important regulators of the gut-brain communication pathways that cause neurodevelopmental and psychiatric problems in adulthood. Intestinal dysbiosis and neurodevelopmental disease outcomes in preterm newborns are being linked by recent research. Recent clinical investigations demonstrate that in critical care units, intestinal dysbiosis occurs before late-onset newborn sepsis and necrotizing enterocolitis. Strong epidemiologic data also shows a connection between necrotizing enterocolitis and extremely low birth weight babies' long-term psychomotor impairments and late-onset neonatal sepsis. The GBA theory suggests that intestinal bacteria may indirectly affect preterm newborns' developing brains. In this review, we emphasize the structure and function of the GBA and discuss how immune-microbial dysfunction in the gut affects the transmission of stress signals to the brain. Preterm babies who are exposed to these signals develop neurologic disorders. Understanding neuronal and humoral communication through the GBA may provide insight into therapeutic and nutritional strategies that may enhance the results of very low-birth-weight babies.

Multi-Walled Carbon-Nanotube-Reinforced PMMA Nanocomposites: An Experimental Study of Their Friction and Wear Properties

This manuscript presents an experimental investigation of the friction and wear properties of poly (methyl methacrylate) (PMMA) nanocomposites reinforced with functionalized multi-walled carbon nanotubes (MWCNTs). The aim of this study is to evaluate the potential of MWCNTs as a reinforcement material for enhancing the tribological performance of PMMA. Three types of multi-walled carbon nanotubes, i.e., pristine, hydroxyl functionalized, and carboxyl functionalized, were utilized in this study. The nanocomposite samples were prepared by dispersing varying concentrations of MWCNTs (0.1 wt.%, 0.5 wt.%, and 1 wt.%) within the PMMA matrix via a 3D mixing approach, followed by injection molding/compression molding. The resulting nanocomposite films were characterized using scanning electron microscopy (SEM) to observe the dispersion of MWCNTs within the PMMA matrix. The friction and wear tests were conducted using a pin-on-disk tribometer under dry sliding conditions. The effects of functionalization and MWCNT content on the tribological behaviors of the nanocomposites were analyzed. The nanocomposites exhibited lower friction coefficients and reduced wear rates compared to pure PMMA. The lowest friction coefficient and wear rate were achieved at an optimum MWCNT loading of 0.5 wt.%. It was further revealed that the amount of MWCNT reinforcement, average load, and track diameter significantly affect the coefficient of friction (COF) and rate of wear. The COF and wear rate are best at a filler loading of 0.5 wt.%, a 20 Kg load, and 90 mm. The improved tribological performance of the MWCNT-reinforced PMMA nanocomposites can be attributed to the effective transfer of load between the MWCNTs and the PMMA matrix, as well as the reinforcement effect of the MWCNTs. The MWCNTs acted as reinforcing agents, enhancing the mechanical properties and wear resistance of the nanocomposites.

Operationalising targeted next-generation sequencing for routine diagnosis of drug-resistant TB

BACKGROUND

Phenotypic drug susceptibility testing (pDST) for Mycobacterium tuberculosis can take up to 8 weeks, while conventional molecular tests identify a limited set of resistance mutations. Targeted next-generation sequencing (tNGS) offers rapid results for predicting comprehensive drug resistance, and this study sought to explore its operational feasibility within a public health laboratory in Mumbai, India.

METHODS

Pulmonary samples from consenting patients testing Xpert MTB-positive were tested for drug resistance by conventional methods and using tNGS. Laboratory operational and logistical implementation experiences from study team members are shared below.

RESULTS

Of the total number of patients tested, 70% (113/161) had no history of previous TB or treatment; however, 88.2% (n = 142) had rifampicin-resistant/multidrug-resistant TB (RR/MDR-TB). There was a high concordance between resistance predictions of tNGS and pDST for most drugs, with tNGS more accurately identifying resistance overall. tNGS was integrated and adapted into the laboratory workflow; however, batching samples caused significantly longer result turnaround time, fastest at 24 days. Manual DNA extraction caused inefficiencies; thus protocol optimisations were performed. Technical expertise was required for analysis of uncharacterised mutations and interpretation of report templates. tNGS cost per sample was US$230, while for pDST this was US$119.

CONCLUSIONS

Implementation of tNGS is feasible in reference laboratories. It can rapidly identify drug resistance and should be considered as a potential alternative to pDST.

Adoption of cleaner technologies and reduction in fire events in the hotspots lead to global decline in carbon monoxide

Carbon Monoxide (CO) is not a greenhouse gas (GHG), but has the capacity to change atmospheric chemistry of other GHGs such as methane and ozone, and therefore indirectly affects Earth's radiative forcing of the GHGs and surface temperature. Here, we use the CO mixing ratio at 850 hPa from the Tropospheric Emission Spectrometer (TES) reanalysis and the Measurement of Pollution in the Troposphere (MOPITT) satellite measurements for the period 2005-2019 to examine the spatio-temporal changes in CO across the latitudes. We find a substantial decrease in global CO, about 0.21 ± 0.09 ppb/yr (0.23 ± 0.12%/yr) with the TES data and about 0.36 ± 0.07 ppb/yr (0.45 ± 0.08%/yr) with the MOPITT satellite measurements during the study period. The highest CO decreasing trend is observed in Eastern China (2.7 ± 0.37 ppb/yr) followed by Myanmar (2.142 ± 0.59 ppb/yr) and South America (1.08 ± 0.82 ppb/yr). This negative trend in CO is primarily due to the decrease in biomass burning and stringent environmental regulations in the respective regions and countries. The sources including road transport that account for about 33.6% of CO emissions, followed by industries (18.3%) and agricultural waste burning (8.8%), might also be responsible for the reduction in CO due to adaptation of improved emission control technology and regulations in the past decade from 2005 to 2019. Therefore, the study provides new insights on the current trends of global CO distribution and reasons for recent reduction in global CO emissions, which would be useful for future decision-making process to control air pollution.

A prospective study of inflammatory bowel disease phenotypes in extremes of age and comparison with adults

BACKGROUND AND AIMS

Pediatric and elderly inflammatory bowel disease (IBD) are less explored, often in retrospective studies. The pediatric group has a more extensive and aggressive disease phenotype requiring aggressive treatments, whereas the elderly group may have less aggressive diseases.

METHODS

We prospectively compared disease characteristics of a single center cohort of IBD patients (pediatric age ≤ 16 years; adults 17 to 59 years; and elderly ≥ 60 years) seen between September 2018 and November 2019 with at least six months of follow-up.

RESULTS

Total 266 IBD patients (137 males) included 47 pediatric, 175 adults and 44 elderly patients. Among ulcerative colitis (UC) patients, pancolitis was more common in the pediatric group (p = 0.018), while the elderly group had more indolent behaviors and infrequent extraintestinal manifestations (p = 0.005). Among patients with Crohn's disease (CD), the pediatric group had more often colonic diseases (p = 0.02) and the elderly, ileal diseases (p = 0.04). The disease behavior was similar in the three age groups. Perianal disease was least common in elderly CD patients (p = 0.03). There was no treatment difference among different age groups in UC. In CD, pediatric patients needed biologics more frequently (p = 0.005), while elderly CD patients less frequently required steroids, biologics, immunosuppressants and surgery (p < 0.05).

CONCLUSIONS

We noted differences compared to western literature such as colonic location in pediatric CD and ileal location in elderly CD. Perianal disease was less frequent in the elderly CD group. There was no difference in treatment in the three age groups in UC, while there were no inter-age-group disease behavioral differences for UC and CD.

Non-surgical organ preservation in laryngeal and hypopharyngeal cancers: an audit from the clinic

BACKGROUND

There is increasing concern regarding efficacy of organ preservation protocol in laryngeal and hypopharyngeal cancers.

METHOD

This study retrospectively assessed disease-related and functional outcomes of 191 patients with non-metastatic laryngeal or hypopharyngeal squamous cell carcinoma treated with curative intent (radiotherapy with or without chemotherapy).

RESULTS

Seventy-six patients (39.8 per cent) had a primary cancer in the larynx, and 115 patients (60.2 per cent) had a primary cancer in the hypopharynx. The median follow up was 39 months. The 3-year time to progression, overall survival, local control and laryngectomy free survival was 56.2 per cent, 76.3 per cent, 73.2 per cent and 67.2 per cent, respectively. At the time of analysis, 83 patients (43.5 per cent) were alive and disease free at their last follow up and did not require tube feeding or tracheostomy. The laryngo-oesophageal dysfunction-free survival was 61 per cent at 3 years.

CONCLUSION

Organ conservation protocols remain the standard of treatment in appropriately selected patients with laryngeal and hypopharyngeal cancers.

In Silico study on Targeting Human C-Reactive Protein Involved in Cardiovascular Disease using Quercetin

Cardiovascular disease is one of the leading causes of death and disability in humans. Quercetin (Que) and its analogs are found in plants naturally and have been shown to have promising bioactive effects. The relationship between “Human C-reactive protein (CRP)” and the cardiovascular system (CVD) has been extensively researched over the last several decades. Numerous studies have looked at Que's potential benefits for a wide variety of medical conditions, including diabetes, inflammation, microbial infection, arthritis, heart disease, and wound healing. In current study the binding affinity of Quercetin against the cardiovascular target protein was analyzed using molecular docking because of the significance of protein-ligand interactions in structure-based drug development. After downloading the CRP (Target Cardiovascular Protein) 3D structure from Protein Data Bank, the authors used the Autodock software to position it in its docking environment and it was reported that the binding energy of Quercetin molecule with CRP is -6.28 kcal/mol. Though more in-vitro studies are required to validate this research. The findings suggest that Quercetin may protect against cardiovascular disease and cancer.

Brainstorm-DUNEuro: An integrated and user-friendly Finite Element Method for modeling electromagnetic brain activity

Human brain activity generates scalp potentials (electroencephalography - EEG), intracranial potentials (iEEG), and external magnetic fields (magnetoencephalography - MEG). These electrophysiology (e-phys) signals can often be measured simultaneously for research and clinical applications. The forward problem involves modeling these signals at their sensors for a given equivalent current dipole configuration within the brain. While earlier researchers modeled the head as a simple set of isotropic spheres, today's magnetic resonance imaging (MRI) data allow for a detailed anatomic description of brain structures and anisotropic characterization of tissue conductivities. We present a complete pipeline, integrated into the Brainstorm software, that allows users to automatically generate an individual and accurate head model based on the subject's MRI and calculate the electromagnetic forward solution using the finite element method (FEM). The head model generation is performed by integrating the latest tools for MRI segmentation and FEM mesh generation. The final head model comprises the five main compartments: white-matter, gray-matter, CSF, skull, and scalp. The anisotropic brain conductivity model is based on the effective medium approach (EMA), which estimates anisotropic conductivity tensors from diffusion-weighted imaging (DWI) data. The FEM electromagnetic forward solution is obtained through the DUNEuro library, integrated into Brainstorm, and accessible with either a user-friendly graphical interface or scripting. With tutorials and example data sets available in an open-source format on the Brainstorm website, this integrated pipeline provides access to advanced FEM tools for electromagnetic modeling to a broader neuroscience community.

Clinical utility of target-based next-generation sequencing for drug-resistant TB

BACKGROUND: In high TB burden countries, access to drug susceptibility testing is a major bottleneck. Targeted next-generation sequencing (tNGS) is a promising technology for rapid resistance detection. This study assessed the role of tNGS for the diagnosis of drug-resistant TB (DR-TB).METHODS: A total of 161 samples from bacteriologically confirmed TB cases were subjected to tNGS using the Deeplex^® Myc-TB kit and sequenced using the MiSeq platform. These samples were also processed for conventional phenotypic DST (pDST) using 13 drugs on Mycobacteria Growth Indicator Tube and line-probe assays (MTBDRplus and MTBDRsl).RESULTS: There were 146 DR-TB and 15 drug-susceptible TB (DS-TB) samples. About 70% of patients with DR-TB had no previous TB treatment history. Overall, 88.2% had rifampicin-resistant/multidrug-resistant TB (RR/MDR-TB), 58.5% pre-extensively drug-resistant TB (pre-XDR-TB) and 9.2% had XDR-TB as defined by the WHO (2020). Around 8% (n = 13) of samples were non-culturable; however, identified 8 were resistant to first and second-line drugs using tNGS. Resistance frequency was similar across methods, with discordance in drugs less reliable using pDST or with limited mutational representation within databases. Sensitivities were aligned with literature reports for most drugs. We observed 10% heteroresistance, while 75% of strains were of Lineages 2 and 3.CONCLUSIONS: Programme data supported tNGS in the diagnosis of DR-TB for early treatment using individualised regimens.

Fatal COVID-19 in a neonate after probable late intrauterine transmission

We report the case of a 35-week gestation infant girl born by emergent cesarean section for fetal distress in a woman with recent coronavirus disease 2019 (COVID-19). Tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using polymerase chain reaction (PCR) on the infant at 24 and 48 hours of life were negative. However, at 72 hours of life, the infant's respiratory status worsened, and a repeat SARS-CoV-2 PCR was positive. The infant developed leukopenia, thrombocytopenia, and progressive respiratory failure, and died on the ninth day of life. Pathologic examination of the placenta revealed findings consistent with COVID-19 placentitis, and SARS-CoV-2 RNA staining was positive, suggesting intrauterine transmission of the infection.

TOLERABILITY OF GRADED CORONAVIRUS DISEASE 2019 MRNA VACCINE DOSING

Introduction

The rapid development of novel coronavirus disease 2019 (COVID-19) mRNA vaccines and their widespread use has raised concerns that they may cause allergic reactions at rates greater than conventional vaccines. Vaccine administration strategies in cases of prior COVID-19 vaccine reaction or patient hesitancy include full dose administration with close observation and graded dosing protocols.

Methods

Retrospective chart review of patients who were referred to an allergy clinic for observed COVID-19 vaccine administration with emphasis on demographic characteristics, atopic co-morbidities, prior vaccine reactions, and outcome of challenge.

Results

Data were available for 83 patients comprising 102 total COVID-19 vaccine challenges. All (n=102) challenges were successful; 21 experienced symptoms and 81 did not. The most reported symptoms were pruritus (n=5), headache (n=5), and chest tightness (n=3). No patient experienced vital sign changes during the protocol and there were no cases of anaphylaxis. The most common dosing protocols were either one-step (n=38) or two-step (n=36). The most common reasons for undergoing challenge were previous COVID-19 vaccine reaction (n=55) and concern for multiple drug allergies (n=21).

Conclusion

This review demonstrates that COVID-19 vaccine graded dosing protocols were highly tolerated and successful regardless of prior COVID-19 vaccine reactions or drug allergies. The presence of symptoms during the challenge did not preclude successful outcome, and no patients experienced anaphylaxis. Given the ongoing nature of the COVID-19 pandemic, it is important to recognize that graded challenge or full dose administration with observation may provide a safe means for patients who are hesitant to pursue COVID-19 vaccination.

Feasibility Analysis of Machining Cobalt-Chromium Alloy (Stellite-6) Using TiN Coated Binary Inserts

The objective of the study was to check the feasibility of machining Stellite 6, a cobalt-chromium superalloy, using TiN-coated carbide inserts in an end milling operation. The inserts were coated using the magnetron sputtering process. The sputtering power and gas flow rate were considered as the variables during the coating process. The performance of the coated binary carbide insert was checked during the end milling of Stellite 6 (~45 HRC) through an experiment with a Taguchi design. Experimental runs based on an orthogonal array were executed for each insert type to check the feasibility of machining this cobalt-based alloy. Adequate precision and the optimum parametric conditions were determined and are reported in this study. Analysis of variance (ANOVA) with a two-factor interaction model was also undertaken to forecast the key elements influencing surface roughness. Based on the ANOVA model, the depth of the cut, combined with the insert type, was the factor that had the greatest influence on surface roughness, followed by the cutting feed, whereas the cutting velocity had the least significance based on the tests. Moreover, the regression analysis demonstrated that the created model can be used to accurately forecast surface roughness in end milling of Stellite 6 with confidence intervals of 95%.

Strength Evaluation of Functionalized MWCNT-Reinforced Polymer Nanocomposites Synthesized Using a 3D Mixing Approach

The incorporation of carboxyl functionalized multi-walled carbon nanotube (MWCNT- COOH) into a polymethyl methacrylate (PMMA) has been investigated. The resultant tensile and flexural mechanical properties have been determined. In this paper, a novel synthesis process for a MWCNT-reinforced polymer nanocomposite is proposed. The proposed method significantly eliminates the most challenging issues of the nano-dispersed phase, including agglomeration and non-homogeneous mixing within a given matrix material, and also resolves the issues occurring in conventional mixing processes. The results of scanning electron microscopy support these claims. This 3D-mixing process is followed by an extrusion process, using a twin-screw extruder for pristine MWCNT, and a compression molding process for COOH-MWCNT, to prepare test specimens for experimentally determining the mechanical properties. The test specimens are fabricated using 0.1, 0.5, and 1.0 wt.% MWCNT, with a remaining PMMA phase. The testing is conducted according to ASTM D3039 and ASTM D7264 standards. Significant improvements of 25.41%, 35.85%, and 31.75% in tensile properties and 18.27%, 48%, and 33.33% in flexural properties for 0.1, 0.5, and 1.0 wt.% COOH-MWCNT in PMMA, respectively, compared to non-functionalized MWCNTs, were demonstrated. The highest strength was recorded for the nanocomposite with 0.5 wt.% f-MWCNT content, indicating the best doping effect at a lower concentration of f-MWCNT. The proposed CNT-PMMA nanocomposite may be found suitable for use as a scaffold material in the domain of bone tissue engineering research. This type of research possesses a high strength requirement, which may be fulfilled using MWCNT. Furthermore, this analysis also shows a significant amount of enhancement in flexural strength, which is clinically required for fabricating denture bases.

Left ventricular unloading with Impella versus IABP in patients on VA-ECMO for cardiogenic shock

Background

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) use for circulatory support in shock is limited by increased left ventricular afterload. Impella and intra-aortic balloon pump (IABP) can be used in conjunction with VA-ECMO to help unload the left ventricle. Data comparing the two strategies are limited.

Purpose

We performed a systematic review and meta-analysis of published data to compare outcomes of patients with shock supported by VA-ECMO in conjunction with Impella versus IABP.

Methods

We conducted a search of Medline, Embase, and Cochrane databases to identify studies comparing the use of Impella versus IABP in patients on VA-ECMO. The primary outcome of interest was all-cause mortality (in-hospital or 30-day). Secondary outcomes included transition to destination therapy with left ventricular assist device (LVAD) or transplant, stroke, need for continuous renal replacement therapy (CRRT), bleeding, and hemolysis. Risk ratios (RR) with 95% confidence interval and the heterogeneity statistic I2 were reported for each outcome.

Results

Six observational studies with a total of 629 patients were included in the analysis. Of these, 205 (33%) and 424 (67%) patients were supported by Impella and IABP respectively, in addition to VA-ECMO. All six studies reported the primary outcome. No difference was observed in all-cause mortality between VA-ECMO with Impella and VA-ECMO with IABP (RR 1.02 [0.74–1.40], I2=74%). Similar rates were observed for transition to LVAD or transplant (RR 0.75 [0.45–1.27], I2=0%), stroke (RR 1.50 [0.80–2.83], I2=0%), and need for CRRT (RR 1.04 [0.82–1.32], I2=0%). However, use of VA-ECMO with Impella was associated with a higher risk of bleeding (RR 1.91 [1.28–2.86], I2=68%) and hemolysis (RR 4.61 [1.24–17.17], I2=66%) as compared with use of VA-ECMO with IABP.

Conclusion

In patients with shock requiring VA-ECMO, concurrent use of Impella and IABP had similar risk of mortality, transition to LVAD/transplant, stroke, and need for CRRT. However, Impella use was associated with higher risk of bleeding and hemolysis. Randomized trials are needed to identify the optimal strategy for left ventricular unloading in patients with cardiogenic shock on VA-ECMO.

Funding Acknowledgement

Type of funding sources: None.

Retinal Haemorrhage in Newborns in Tertiary Care Hospital

Background Retinal haemorrhage in new-born is a clinically common neonatal fundus condition. Although, it usually does not affect the development of visual function, entities like macular haemorrhages may lead to amblyopia causing deterioration of visual function. Such scenario leads to downgrade in quality of life of the affected child. Objective To explore the underlying clinical factors associated with retinal haemorrhage in term new-borns. Method A cross sectional study was conducted involving 136 term neonates admitted in the neonatal intensive care unit of Dhulikhel Hospital. Fundus examination was performed within 2 weeks of delivery. Retinal haemorrhage was graded according to their location in three retinal zones. Result Out of 136 cases examined, 44 (32.35%) of the cases had one of the eyes with retinal haemorrhage. Where grade 1 retinal haemorrhage was accounted in majority of the cases. Birth weight, gestational age, mode of delivery, poor Appearance, Pulse, Grimace, Activity, and Respiration (APGAR) Score in 1 and 5 minutes, birth asphyxia, neonatal sepsis and heavy work in antenatal period had statistically significant correlation with occurrence of retinal haemorrhage. Conclusion Our results suggest that spontaneous vaginal delivery, larger birth weight, higher gestational age, birth asphyxia, low Appearance, Pulse, Grimace, Activity, and Respiration score, are risk factors for occurrence of neonatal retinal haemorrhage. It is recommended that in neonates with above high-risk factors should undergo targeted fundus screening for early identification and needful interventions.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Analysis of Perception of Students and Faculty on Case Based Early Clinical Exposure in First Year Medical Students

Early clinical exposure (ECE) is a novel strategy for medical colleges to bridge the gap between basic and clinical sciences. There are few studies that explain student's and faculty's perspective on ECE. This study compares the ECE models (Case-based and Video-based case) in terms of benefits and challenges. This cross-over comparative study with 120 medical students of MBBS Batch 2019 and 8 facilitators was conducted in Government medical college, Pali, Rajasthan, India from September 2020 to March 2021. Entire batch was divided into two groups. In a hospital environment, one group was taught by an actual case (patient) of a specific topic, while another group was taught in a classroom setting by a video-based case. The students' and faculty's perspectives on Case-Based Early Clinical Exposure (CBECE) were documented using a pre-tested questionnaire and evaluated on a Likert scale. Finally, both groups were given assessment questions and the process was repeated in the following session of case based early clinical exposure, but with switched groups. Majority of the students (98.3%) agreed CBECE as more effective for attentiveness, retention, correlation of clinical knowledge with theoretical knowledge and communication. Most of the students (43.0%) believed that learning is limited due to lack of repeatability as compare with video-based case. Most of the facilitators found CBECE as effective tool for the development of attitude and communication skills of the students. CBECE can be implemented with limited sessions for sensitization of students about health care setup, importance of empathetic behavior, communication skill and better correlation of preclinical subjects in the context of disease.

MicroRNA biomarkers of platelet function

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation (BHF), VASCage (Centre for Promoting Vascular Health in the Ageing Community) of the Austrian Research Promotion Agency FFG (COMET program - Competence Centers for Excellent Technologies)

Introduction

Antiplatelet therapy (APT) leads to reduced morbidity and mortality in patients with cardiovascular disease but some still have thrombotic events. Tailoring APT to platelet function is currently limited by a lack of suitable platelet function tests. It has been previously shown that different circulating microRNAs (miRNAs) are derived from platelets and their measurement could provide new markers of platelet reactivity.

Purpose

To compare the release of different platelet miRNAs in response to different platelet agonists.

Methods

Measurements of platelet function were performed by light transmission aggregometry (LTA) in participants of the 2015 follow-up of the Bruneck study (n=338), using the following agonists: arachidonic acid (1mM), adenosine diphosphate (5µM, 20µM), collagen (0.4 µg/ml, 4 µg/ml, 10µg/ml), TRAP-6 amide (25µM) and U46619 (10µM). LTA platelet releasates were then used for RT-qPCR measurements of five platelet-enriched miRNAs (miR-21, miR-126, miR-150, miR-197, miR-223). Platelet-poor plasma (PPP) served as negative control.

Results

Platelet activation led to aggregation and extracellular release of miRNAs, with aspirin users (n=155) showing significantly lower miRNA release than non-aspirin users (n=183). Agonist responsiveness differed among miRNAs, with miR-21 being hyperresponsive to arachidonic acid and miR-150 being hyperresponsive to adenosine diphosphate, whilst release of miR-126, miR-197 and miR-223 was strongest to collagen (10µg/ml). In non-aspirin users, inflammation markers such as granulocyte counts or C-reactive protein correlated positively with platelet-derived miRNAs measured in PPP, whilst they correlated negatively with platelet-derived miRNAs measured in releasates. These effects were absent in aspirin users.

Conclusions

MiRNAs released from activated platelets can be reliably detected in PPP and platelet releasates. Preferential release of miRNAs in response to specific agonists suggests a selective release mechanism. Elevated PPP levels and decreased releasate levels of platelet-derived miRNAs in inflammatory environments suggest platelet exhaustion ex vivo due to platelet pre-activation.

POS1443 IDENTIFYING THE NEW EMERGENCE OF RACIAL DISPARITIES IN GOUT OVER THE PAST 3 DECADES – US NATIONAL SURVEY AND PROSPECTIVE COHORT DATA

Background

Several studies published after 2010 reported a higher frequency of gout and hyperuricemia among US Blacks than Whites.1-4 However, Blacks (in the US and Africa) were previously thought to suffer gout less often than Whites.5 We hypothesized that the racial disparity in Blacks emerged over the past several decades, with flipped prevalence between the two races.

Objectives

To assess trends in racial differences in gout prevalence in the US using both national survey and cohort study data over the past 3 decades.

Methods

Using data from the NHANES (National Health and Nutrition Examination Survey) III (1988-1994) and latest decade (2007-2016), and data from 5 examination periods in the ARIC (Atherosclerosis Risk in Communities) Study between 1988 through 2013, we compared age- and sex-adjusted prevalences and odds ratios (OR) to determine the trend of racial differences in gout prevalence between Blacks and Whites. A time-race interaction term was used to assess differences in the rate of change between the two races.

Results

Among Whites, the sex- and age-standardised prevalence of gout in the NHANES rose from 2.8% (95% CI: 2.4 to 3.2) in 1988-94 to 3.7% (3.2 to 4.1) in 2007/16. Prevalence of gout among Blacks was lower than Whites in 1988-94 (2.6% [2.2 to 3.0]) but rose more sharply over the subsequent decades (p for race-time interaction=0.003), and in 2007/16 came to exceed that of Whites (5.0% [4.4 to 5.6]).

Corresponding age-sex-adjusted ORs for gout in Blacks vs. Whites were 0.93 (0.73 to 1.17) in 1988-94, increasing to 1.46 (1.22 to 1.74) in 2007/16 (Table 1). This disproportionate rise in gout prevalence among Blacks tended to be more prominent among women (OR 1.81 [1.29 to 2.53]) than men (OR 1.26 [1.02 to 1.55]; p for race-time interactions of 0.002 and 0.01, respectively). Similar trends were observed in the ARIC cohort, where the OR for gout among Blacks vs. Whites rose progressively from 0.82 (0.65 to 1.02) in 1987-89 to 1.81 (1.49 to 2.19) in 2011-13.

Table 1.

Temporal Trend of Racial Disparity in Gout Prevalence in NHANES Survey and the ARIC Study Cohort, overall and by sex

Odds Ratio (95% CI) for Gout Among Blacks vs. WhitesOVERALLNHANES1988-19942007-2016Age- and sex-adjusted0.93(0.73 to 1.17)1.46(1.22 to 1.74)ARICVisit 1: 1987-89Visit 2: 1990-92Visit 3: 1993-95Visit 4: 1996-98Visit 5: 2011-13Age- and sex-adjusted0.82(0.65 to 1.02)0.99(0.81 to 1.22)1.24(1.03 to 1.50)1.60(1.35 to 1.90)1.81(1.49 to 2.19)WOMENNHANES1988-19942007-2016Age-adjusted0.98(0.65 to 1.47)1.81(1.29 to 2.53)ARICVisit 1: 1987-89Visit 2: 1990-92Visit 3: 1993-95Visit 4: 1996-98Visit 5: 2011-13Age-adjusted0.92(0.64 to 1.32)1.14(0.82 to 1.59)1.45 (1.07 to 1.96)1.89 (1.45 to 2.46)2.28(1.73 to 3.01)MENNHANES1988-19942007-2016Age-adjusted0.91(0.68 to 1.21)1.26 (1.02 to 1.55)ARICVisit 1: 1987-89Visit 2: 1990-92Visit 3: 1993-95Visit 4: 1996-98Visit 5: 2011-13Age-adjusted0.73 (0.54 to 0.97)0.87 (0.66 to 1.14)1.03(0.79 to 1.33)1.29(1.02 to 1.64)1.34(1.00 to 1.78)

Conclusion

Gout prevalence tended to be lower in Blacks than Whites until late 80’s, then rose and surpassed that of Whites over the past several decades. These trends closely parallel the worsening obesity epidemic during this period,6 particularly in Blacks, partly due to enhanced Western lifestyle. Gout risk genetic profile change would not contribute to this emergence of racial differences, particularly among the same individuals in ARIC, although it remains to be clarified whether Blacks carry genetic profiles that enhance the effect of lifestyle risk factors for gout.

References

[1]PMID 22225548 (2012)

[2]PMID 24330409 (2013)

[3]PMID 24335384 (2014)

[4]PMID: 30618180 (2019)

[5]NEJM PMID: 15014177

[6]JAMA PMID: 12365955

Disclosure of Interests

Natalie McCormick: None declared, Leo Lu: None declared, Chio Yokose: None declared, Amit Joshi: None declared, Yuqing Zhang: None declared, Hyon Choi Consultant of: Ironwood, Selecta, Horizon, Takeda, Kowa, and Vaxart., Grant/research support from: Ironwood and Horizon

POS0280 EXCESS RISK OF ALL-CAUSE AND CARDIOVASCULAR MORTALITY IN FEMALES WITH GOUT – A PROSPECTIVE COHORT STUDY OF 105,502 WOMEN

Background

Despite the disproportionately worsening disease burden of female gout in recent years1 and its frequent associations with key cardiovascular risk factors (more often than male gout2,3), there remains a paucity of specific data about female gout, particularly about its impact on mortality and fatal coronary heart disease (CHD).

Objectives

To prospectively examine the relation of female gout and risk of all-cause and cardiovascular and coronary heart disease-specific deaths.

Methods

Using data from the Nurses’ Health Study (NHS), an ongoing prospective cohort study in which female nurses in the United States completed detailed mailed questionnaires regarding their medical history, lifestyle, and other risk factors at baseline and every two years thereafter, we prospectively analyzed the relation between gout status at baseline and during the follow-up period and the risk of all-cause and cardiovascular mortality using Cox proportional hazards regression to adjust for cardiovascular risk factors such as comorbidities, body mass index, postmenopausal status, medication use, and dietary factors.

Results

The analysis included 105,502 women without gout and 1602 women with gout. Women with gout at baseline in 1982 tended to be older (mean age 54 vs. 50 years), and more likely to report a history of hypertension (44% vs. 22%), hypercholesterolemia (17% vs. 8%), and diabetes (11% vs. 6%). During 24 years of follow-up, we documented 15,255 deaths from all causes, including 3,128 deaths from cardiovascular disease (CVD) and 1,405 deaths from coronary heart disease (CHD). Compared to women without history of gout or CHD at baseline, the multivariable relative risks (RRs) among women with history of gout at baseline were 1.33 (95% CI, 1.21 to 1.46) for total mortality, 1.40 (95% CI, 1.17 to 1.67) for CVD deaths, and 1.49 (95% CI, 1.17 to 1.91) for fatal CHD (Table 1). The corresponding RRs for gout at baseline and during the follow-up were 1.33 (95% CI, 1.23 to 1.44), 1.43 (95% CI, 1.24 to 1.66), and 1.34 (95% CI, 1.08 to 1.66), respectively.

Table 1.

Relative Risks of Death from All-Causes, Cardiovascular Disease, and Coronary Heart Disease According to Gout Status at Baseline in 1982 in the Nurses’ Health Study

No CHDNo GoutGoutDeaths from all causesCases, n14,810445Age-adjusted RR (95% CI)1.01.58 (1.43, 1.73)Multivariable-adjusted* RR (95% CI)1.01.33 (1.21, 1.46)All cardiovascular deathsCases, n3,001127Age-adjusted RR (95% CI)1.02.06 (1.72, 2.46)Multivariable-adjusted* RR (95% CI)1.01.40 (1.17, 1.67)Fatal CHDCases, n1,33570Age-adjusted RR (95% CI)1.02.53 (1.99, 3.22)Multivariable-adjusted* RR (95% CI)1.01.49 (1.17, 1.91)

*Adjusted for age (continuous), history of hypertension, history of hypercholesterolemia, history of diabetes, aspirin use (yes, no), diuretic use (yes, no), smoking (never, past, current <15, current ≥15 cigarettes/day), body mass index (<23, 23-24.9, 25-29.9, 30-34.9, ≥35), physical activity (quintile), alcohol intake (nondrinker, <5, 5-9, 10-29, ≥30g/day), family history of MI (yes, no), menopausal status (premenopause, post menopause), hormone replacement therapy use (premenopause, never user, current user, past user). total energy intake (quintile), trans fat (quintile), dietary cholesterol (quintile), protein (quintile), linoleic fatty acid (quintile), and ratio of polyunsaturated fat/saturated fat.

CHD = coronary heart disease; CI = confidence interval; RR = relative risk.

Conclusion

These prospective data indicate that women with gout have a higher risk of all-cause mortality, which is primarily driven by higher risk of CVD deaths. These findings closely agree with the UK general population data of both sexes that showed unclosing mortality gap over the past two decades.4 Together, these findings provide support for rigorous cardiovascular risk factor modification specifically in female gout to help curtail the rising disease burden of gout worldwide.1

References

[1]Xia et al., PMID 31624843

[2]Puig et al., PMID 2012455

[3]Harrold et al., PMID 16644784

[4]Fisher et al., PMID 28122760

Disclosure of Interests

Chio Yokose: None declared, Natalie McCormick: None declared, Na Lu: None declared, Amit Joshi: None declared, Gary Curhan Consultant of: AstraZeneca, Allena Pharmaceuticals, Shire/Takeda, Dicerna, and Orfan, Grant/research support from: Decibel Therapeutics, Employee of: Chief Medical Officer at OM1, Inc., Hyon Choi Consultant of: Ironwood, Selecta, Horizon, Takeda, Kowa, and Vaxart, Grant/research support from: Ironwood and Horizon

POS0155 WHAT DRIVES RACIAL DISPARITIES IN GOUT IN THE US? – POPULATION-BASED, SEX-SPECIFIC, CASUAL MEDIATION ANALYSIS

Background

Traditionally viewed as a disease of White men, global frequency and disability burden of female gout are rising disproportionately to male gout.1 Moreover, emerging US cohort data suggest gout and hyperuricemia impart larger burdens on Black adults than Whites.2 These racial disparities may be largely attributable to differences in non-genetic, mainly modifiable gout risk factors e.g., BMI, diet,3,4 and chronic kidney disease (CKD). However, national-level, general population data on racial differences in burden of gout, and potential mediators, are lacking.

Objectives

To determine and quantify sex-specific mediators of racial disparities in gout prevalence among a nationally representative sample of US adults.

Methods

Using recent decadal data (2007-2016) on physician-diagnosed gout and hyperuricemia from the National Health and Nutrition Examination Survey, we compared contemporary sex- and race-specific prevalences and conducted sequential causal mediation analysis (adjusting for upstream mediators following causal pathways)5 to determine the proportion of the racial differences attributable to 7 potentially mediating social and clinical factors (see DAG in Figure 1): low education, poverty, body mass index (BMI), alcohol, poor quality diet (poor DASH adherence), diuretic use, and CKD (eGFR <60 mL/min, using the latest equations that do not include a coefficient for Black race6, per National Kidney Foundation and American Society of Nephrology recommendations.7)

Results

Age standardised prevalence of gout was 3.5% and 2.0% in Black and White women, respectively (age-adjusted OR =1.8 [95% CI: 1.3 to 2.5]), and 7.0% and 5.4% in Black and White men (age-adjusted OR =1.3 [1.0 to 1.6]). Most risk factors were more frequent/elevated in Blacks than Whites, except alcohol consumption, which was lower in Blacks (both sexes). BMI levels and poverty were higher in Black women, but similar between Black and White men.

Largest mediating factor of excess gout cases among Black women was excess BMI, accounting for 56% of the racial difference (independent of education, poverty, diet, and alcohol), followed by CKD (24%), poverty (17%), and poor diet (12%) (see Table 1).

Table 1.

Indirect (mediation) effects of potential mediators, using sequential mediation analysis, for the association between Black race and odds of gout in US women and men.

WOMENMENEffect Estimate (OR), 95% CIProportion Mediated, %Effect Estimate (OR), 95% CIProportion Mediated, %Indirect (Mediation) EffectEducation (high school or less)1.01 (0.98 to 1.03)2.4%1.01 (0.98 to 1.03)3.3%Poverty1.07 (1.04 to 1.10)16.9%1.00 (0.99 to 1.00)0.53%Alcohol consumption (# drinks/week, continuous)0.99 (0.96 to 1.01)-3.4%0.99 (0.98 to 1.00)-4.5%DASH diet score (continuous; higher scores = ↓ adherence)1.05 (0.96 to 1.01)12.0%1.05 (1.01 to 1.10)19.8%Body mass index (continuous)1.25 (1.14 to 1.37)55.9%1.03 (1.02 to 1.04)11.9%Diuretic use1.03 (1.01 to 1.05)7.6%1.04 (1.02 to 1.06)14.2%Chronic kidney disease1.10 (1.04 to 1.16)23.9%1.12 (1.08 to 1.17)45.6%Direct Effect0.94 (0.68 to 1.30)a−15.2%1.02 (0.83 to 1.26)b9.2%Total Effect1.49 (1.12 to 1.98)100%1.29 (1.05 to 1.57)100%

DASH=Dietary Approaches to Stop Hypertension;

ap=0.52,

bp=0.83

Among men, CKD was the largest mediator (46%), followed by poor diet (20%) and diuretic use (14%). BMI (12%) and poverty (0.5%) mediated smaller proportions of the racial difference among men compared to women. Mediators of racial differences in hyperuricemia closely agreed with gout results.

Conclusion

Contrasting with historical views, gout is more frequent among Black adults in the US than their White counterparts, especially women (two-times greater in Black women vs. White). Culturally informed efforts to reduce these disparities should focus on excess adiposity, diet quality, and kidney disease while recognising the impact of poverty in female gout.

References

[1]Xia; PMID 31624843

[2]PMID 24335384

[3]Rai BMJ PMID 28487277

[4]Yokose JAMA IM (2022)

[5]VanderWeele; PMID 25580377

[6]NEJM PMID 34554658

[7]JASN PMID 34556489

Disclosure of Interests

Natalie McCormick: None declared, Leo Lu: None declared, Chio Yokose: None declared, Amit Joshi: None declared, Tony Merriman: None declared, Kenneth Saag Consultant of: Arthrosi, Atom Bioscience, Horizon Therapeutics, LG Pharma, Mallinkrodt, SOBI, Takeda, Grant/research support from: Horizon Therapeutics, SOBI, Shanton, Yuqing Zhang: None declared, Hyon Choi Consultant of: Ironwood, Selecta, Horizon, Takeda, Kowa, and Vaxart.

Grant/research support from: Ironwood, Horizon

OP0166 CHRONIC KIDNEY DISEASE AND AMPLIFICATION OF SERUM URATE IMPACT ON GOUT RISK: POPULATION-BASED STUDY OF > 450,000 UK BIOBANK PARTICIPANTS

Background

Serum urate (SU) is a necessary causal factor for development of gout, while chronic kidney disease (CKD) is associated with increased inflammatory biomarkers, cytokines, and reduced AMPK activity levels. Furthermore, CKD has been found to be associated with an increased risk of incident gout, even beyond (i.e., independent of) SU levels. As such, the impact of SU may be enhanced by presence of CKD, but this hypothesis has not been evaluated.

Objectives

To prospectively examine whether CKD modifies the relation between SU levels and risk of incident gout.

Methods

We conducted a prospective cohort analysis of UK Biobank participants with urate and creatinine levels available from baseline blood samples (2006-2010), and no prior diagnosis of gout or urate lowering therapy use. CKD Stage ≥ 3 status (eGFR <60 mL/min) was determined from latest CKD-Epi equations (NEJM 2021; JASN 2021).1,2 Incident cases of gout were ascertained from linked hospitalisation, primary care, and death records. Participants were followed from baseline up to 10 years or until gout diagnosis, death, or end of study period (Dec 31/19).

We calculated 10-year cumulative incidence of gout according to baseline SU category and CKD status and evaluated their individual and joint impact on gout risk using multivariable Cox proportional hazards models.

We further assessed for additive and multiplicative interactions3 between levels of SU and inverted eGFR, on a standardized continuous scale per SD.

Results

We included 458,244 individuals (45% male, mean age 56.5 years), of whom 6,559 had CKD at baseline, and documented 5,847 cases of incident gout over 4,442,866 person-years.

10-year cumulative incidence of gout ranged from 0.2% (baseline SU < 5 mg/dL) to 33% (baseline SU ≥ 10 mg/dL), and in each category incidence was higher for those with CKD than without (Table 1; Figure 1-left), Multivariable hazard ratio (HR) for the joint effect of CKD and highest SU level (≥ 10 mg/dL), compared to non-CKD and lowest SU (<5mg/dL), was 242 (95% CI: 189 to 309) (Figure 1-right).

Table 1.

Cumulative incidence and hazard ratio (HR) of incident gout according to baseline serum urate levels and CKD status

CKD Stage ≥ 3Hyperuricemia (Dichotomous)Serum urate, mg/dL<55.0 to < 6.06.0 to < 7.07.0 to < 8.08.0 to < 9.09.0 to < 10.0≥10<7.0≥7.0N cases6152895150104874943610-Year Cumulative Incidence0.6%1.1%1.7%7.6%19.1%28.0%42.0%1.2%16.6%Incidence Rate Ratio1.0 (Ref)1.72.712.333.856.1107.71.0 (Ref)15.2No CKDSerum urate, mg/dL<55.0 to < 6.06.0 to < 7.07.0 to < 8.08.0 to < 9.09.0 to < 10.0≥10<7.0≥7.0N cases393446105617691251363841,8953,46710-Year Cumulative Incidence,0.2%0.4%1.4%6.0%15.6%23.5%27.5%0.5%8.8%Incidence Rate Ratio1.0 (Ref)2.18.034.696.9155.9198.81.0 (Ref)20.2Joint Effect of Serum Urate and CKDSerum urate, mg/dL<55.0 to < 6.06.0 to < 7.07.0 to < 8.08.0 to < 9.09.0 to < 10.0≥10<7.0≥7.0Age-, Sex-, and Race- Adjusted HRNo CKD1.0 (Ref)1.97.029.883.0133.3170.31.0 (Ref)15.7CKD3.25.17.834.193.3155.9302.32.530.5Fully adjusted HR*No CKD1.0 (Ref)1.86.425.869.4108.7132.91.0 (Ref)12.5CKD3.14.76.828.975.2121.1241.82.322.4

*Adjusted for age, sex, race, body mass index, hypertension, diuretic use, smoking, and consumption of alcohol, coffee, meat, fish, poultry, and milk.

There was a significant additive interaction between continuous SU and eGFR (relative excess risk due to interaction=0.16 [0.09 to 0.24], p < 0.001), with HRs of 3.7 (3.6 to 3.8) per SD increase of SU, 1.2 (1.2 to 1.3) per SD increase of inverted eGFR, and 4.1 (3.9 to 4.2) for their joint effect. Their multiplicative interaction was also significant (p < 0.001).

Conclusion

These large prospective cohort data suggest CKD presence enhances the effect of elevated SU levels on risk of incident gout. They support roles of CKD-associated factors beyond SU in developing gout, such as reduced AMPK activity levels and altered inflammatory factors in CKD, which warrant further investigation.

References

[1]PMID 34554658

[2]PMID 34556489

[3]ARD (2021) PMID 34857519

Disclosure of Interests

Natalie McCormick: None declared, Leo Lu: None declared, Chio Yokose: None declared, Amit Joshi: None declared, Yuqing Zhang: None declared, Hyon Choi Consultant of: Ironwood, Selecta, Horizon, Takeda, Kowa, and Vaxart., Grant/research support from: Ironwood and Horizon

OP0164 A POPULATION-BASED, PROSPECTIVE METABOLOMICS STUDY IN THE UK BIOBANK IDENTIFIES GLYCOPROTEIN ACETYLS AS A NOVEL BIOMARKER OF INCIDENT GOUT

Background

Serum urate (SU) level is the strongest known causal predictor of clinical gout, but only ~20% with prolonged hyperuricemia develop gout, motivating the need for additional biomarkers for risk prediction and stratification. The metabolome represents a compelling intermediate trait between genome and phenome to elucidate disease mechanisms. Multiple cross-sectional studies of prevalent gout from men in Asia have been conducted, but no prospective data for incident gout (prediagnostic metabolome) are available.

Objectives

Our objectives were to (1) conduct a discovery-based metabolome-wide study to identify novel biomarkers of incident gout; and (2) replicate novel metabolomic biomarkers of gout in independent samples.

Methods

We conducted a prospective cohort analysis of 105,703 UK Biobank (UKB) participants (46% males, mean age 57.2 years) with targeted NMR metabolomic profiling (N=168 metabolites, including routine lipids and amino acids) available from baseline samples (2006-10), and no prior diagnosis of gout or urate lowering therapy use. Incident cases of gout were documented from linked medical records until gout diagnosis, death, or end of study period (Dec 31/19). We used Cox proportional hazard models to obtain hazard ratios (HR) and 95% confidence intervals (CIs) per standard deviation (SD) increase in each of the 168 metabolites to determine associations with incident gout.

To replicate our findings, we assessed association of metabolome-wide significant metabolites in a replication set, restricted to 4,804 non-overlapping participants who provided blood in the repeat assessment visit (2012-13).

Results

During a median 10.4 years follow-up, we documented 1,367 cases of incident gout in the discovery set. After correction for multiple comparisons, glycoprotein acetyls (GlycA) were positively associated with risk of incident gout (multivariable HR per 1SD increase = 1.34 (1.27 to 1.41), P = 9.04x 10-28) after adjusting for age, sex, and lifestyle and clinical covariates (Table 1). This association persisted even after SU adjustment (HR 1.07, P = 0.0091). In the replication set, among 4,804 participants followed for a median of 6.8 years, we documented 22 cases. In this dataset, we replicated GlycA association with incident gout (multivariable HR per 1SD increase =1.56 (1.08 to 2.25), P = 0.017).

Table 1.

Association of glycoprotein acetyls (GlycA) with risk of incident gout in the UK Biobank

ModelUnivariable HR, (95% CI)PMultivariable HR, (95% CI)PDiscovery (N= 105,703)Per Standard deviation:GlycA, per SD1.48 (1.41 to 1.60)3.7x10-591.34 (1.27 to 1.41)9.04x 10-28Categorized as quintiles:GlycA, Q11.0 Ref1.0 RefGlycA, Q21.43 (1.13 – 1.80)0.0021.30 (1.03 – 1.64)0.0252GlycA, Q32.06 (1.66 – 2.56)4.88 x 10-111.73 (139 – 2.15)7.64 x 10-07GlycA, Q42.53 (2.05 – 3.12)4.15 x 10-181.98 (1.60 – 2.45)3.96 x 10-10GlycA, Q53.70 (3.02 – 4.52)3.21 x 10-372.63 (2.12 – 3.23)2.01 x 10-19Replication (N= 4804)Per Standard deviation:GlycA, per SD1.65 (1.19 to 2.29)0.00271.56 (1.08 to 2.25)0.0172

1 Hazard ratios (HR) and 95% confidence intervals (CIs) obtained after adjusting for the first 4 genomic principal components (controlling for population stratification), age, sex, fasting (<4 hrs, 4-8 hrs and ≥8 hrs), smoking (never, former, current), freq of alcohol, BMI, diabetes (yes/no) and hypertension at baseline (yes/ no).

Conclusion

In this large-scale, prospective metabolomics study, we identified and independently replicated our findings that plasma levels of GlycA are associated with incident gout in UKB participants. GlycA is novel for gout, though this pro-inflammatory biomarker has predicted risk of other cardiometabolic-inflammatory phenotypes, independent of CRP.1 These findings may provide insight into the metabolic-inflammatory pathogenesis of gout, with implications for risk prediction, even beyond SU, but call for further investigation with more extensive metabolome profiling and external replication.

References

[1]Kettunen; PMID 30571186

Disclosure of Interests

Amit Joshi: None declared, Natalie McCormick: None declared, Chio Yokose: None declared, Na Lu: None declared, Hyon Choi Consultant of: Ironwood, Selecta, Horizon, Takeda, Kowa, Vaxart, Grant/research support from: Ironwood, Horizon

POS1171 TRIPLE THE RATE OF EMERGENCY ROOM VISITS AND HOSPITALIZATIONS FOR GOUT AMONG US BLACKS VS WHITES – 2019 NATIONWIDE ANALYSIS

Background

Gout is a highly prevalent inflammatory arthritis with increasing global disease burden in recent years.1,2 Gout prevalence has been reported to be higher among Blacks compared to Whites,3 and that they are less likely to receive allopurinol in outpatient care.4 The potential nationwide impact of these racial disparities on emergency department (ED) visits and hospitalizations is unknown.

Objectives

To examine the contemporary racial disparities in ED visits and hospitalizations with a primary discharge diagnosis of gout in the US (2019).

Methods

We compared ED visits and hospitalizations between Blacks and Whites in the latest data (2019) from the US National Emergency Department Sample (NEDS) and National Inpatient Sample (NIS). We focused on encounters for which the primary diagnosis was gout based on ICD codes (M1A.xx, M10.xx). We calculated annual population rates of ED visits and hospitalizations for gout (per 100,000 US adults) using the 2019 US census adult population (>18 years) according to race.

Results

There were a total of 160,759 ED visits and 9,560 hospitalizations among White and Blacks with a gout diagnosis in the US in 2019. The mean age (58.2 years vs. 56.5 years) and male proportion (78.0% vs. 74.8%) tended to be higher among Whites, while more Blacks tended to live in the South (40.7% vs. 66.5%) and reported a median household income of < $50,000 (30.7% vs. 57.1%). Compared to Whites, Blacks had 2.7- and 3.2-fold higher rates of gout ED visits and hospitalizations, respectively, after adjusting for age, sex, payer, region, and household income (Table 1 & Figure 1). Black women, in particular, had 3.4- and 4.0-fold higher rates of ED visits and hospitalizations compared to White women, while the corresponding rate ratios for men were 2.5 and 2.8, respectively. The mean costs per gout ED visit were similar for Blacks compared to Whites (adjusted difference, -$7.6 [95% CI, -25.4 to 1.0]), while hospitalizations were more costly (adjusted difference, $1,055.3 [95% CI, 553.1 to 1557.5]). The duration of ED visits and hospitalizations was also higher among Blacks than Whites (adjusted difference of 0.41 days [95% CI, 0.19 to 0.63] and 0.59 days [95% CI, 0.25 to 0.94], respectively).

Table 1.

Racial Disparities in Emergency Department Visits and Hospitalizations with Primary Diagnosis of Gout in 2019

Emergency Department VisitsHospitalizationsRaceWhiteBlackWhiteBlackAll6801196524521330198510434519150Visits, N888107194962003360Rate per 100,000130.6293.431.274.4Rate Ratio (95% CI)*1.0 (ref)2.81 (2.63, 3.00)1.0 (ref)3.08 (2.79, 3.40)Rate Ratio (95% CI)**1.0 (ref)2.66 (2.50, 2.82)1.0 (ref)3.17 (2.86, 3.50)Women3785136914363031110390932647105Visits, N195671816317701145Rate per 100,00051.7126.516.043.3Rate Ratio (95% CI)*1.0 (ref)3.68 (3.39, 3.99)1.0 (ref)4.01 (3.40, 4.73)Rate Ratio (95% CI)**1.0 (ref)3.36 (3.11, 3.62)1.0 (ref)4.02 (3.39, 4.78)Men301561011015657388098151871620Visits, N692285378344302215Rate per 100,000229.6529.550.3118.3Rate Ratio (95% CI)*1.0 (ref)2.59 (2.42, 2.78)1.0 (ref)2.66 (2.36, 3.00)Rate Ratio (95% CI)**1.0 (ref)2.47 (2.32, 2.64)1.0 (ref)2.77 (2.45, 3.14)

*Adjusted for age and sex for all, adjusted for age for sex-specific rate ratios

**Adjusted for age, sex, payment, region, and household income

Conclusion

These latest national data indicate that ED visits and hospitalization due to gout are both 3 times higher among Blacks than Whites; this disparity was particularly prominent among women with gout. Higher risk of developing gout3 and suboptimal care4 both translate to these avoidable costly healthcare utilizations, calling for improved primary prevention and gout care.

References

[1]Safiri et al., PMID 32755051

[2]Xia et al., PMID 31624843

[3]Chen-Xu et al., PMID 30618180

[4]Krishnan et al., PMID 18260174

Disclosure of Interests

Chio Yokose: None declared, Natalie McCormick: None declared, Na Lu: None declared, Amit Joshi: None declared, Lesley Jackson: None declared, Minna Kohler Speakers bureau: Lilly, Consultant of: Mymee, Novartis, Grant/research support from: Setpoint Medical, Janeth Yinh: None declared, Yuqing Zhang: None declared, Kenneth Saag Consultant of: Arthrosi, Atom Bioscience, Horizon Therapeutics, LG Pharma, Mallinkrodt, SOBI, Takeda, Grant/research support from: Horizon Therapeutics, SOBI, Shanton, Hyon Choi Consultant of: Ironwood, Selecta, Horizon, Takeda, Kowa, and Vaxart, Grant/research support from: Ironwood and Horizon

Short term outcome of patients attending a renal-immunology clinic in central India

Background:

Glomerular diseases (GDs) and other renal immunologic diseases are an important cause of morbidity and mortality. Providing a single point of service in collaboration with various specialists at a renal immunology clinic for such patients is not novel, but outcomes have not been reported. Here, we report the short-term outcome of Indian patients attending our clinic.

Methods:

This single-center prospective cohort study enrolled biopsy-proven immunologically-mediated adults with renal diseases between April 2018 and December 2019, and followed them for six months. The primary end point for the analysis was an incidence of end-stage renal disease (ESRD) or loss of >50% estimated glomerular filtration rate (eGFR) and patient survival at six months. Secondary endpoints were the rate of complete or partial remission, and impact of demographic factors.

Results:

Ninety two patients underwent renal biopsy for suspected immunological renal diseases. Fourteen (15.2%) cases were excluded for nonimmune etiologies, whereas 78 (84.7%) confirmed cases of immune etiology were included. Most common primary GD (n = 51) (93.5%) was membranous nephropathy (n = 20) (25.6%), whereas lupus nephritis was the most common (n = 8) (29.6%) secondary GD. Overall, 10 (12.8%) patients reached renal endpoint of ESRD or >50% fall in eGFR. Focal segmental glomerulosclerosis (FSGS) (27%) patients had worst renal outcome. Patient survival was 94.8%. Thirty patients (38.4%) achieved complete, whereas 24 each (30.7%) achieved partial remission and remained resistant to disease specific therapies, respectively. Univariate analysis identified hypertension, severity of hypertension, and resistance to achieve proteinuria remission as significantly associated (P < 0.001) factors with poor renal outcome.

Conclusions:

The present study shows that short term renal outcome of Indian patients with renal immune diseases remains poor. FSGS remains the GD with the worst renal outcome. Hypertension, its severity, failure to achieve proteinuria remission were significantly associated with poor renal outcomes.