Frequency, kinetics and determinants of viable SARS-CoV-2 in bioaerosols from ambulatory COVID-19 patients infected with the Beta, Delta or Omicron variants

Airborne transmission of SARS-CoV-2 aerosol remains contentious. Importantly, whether cough or breath-generated bioaerosols can harbor viable and replicating virus remains largely unclarified. We performed size-fractionated aerosol sampling (Andersen cascade impactor) and evaluated viral culturability in human cell lines (infectiousness), viral genetics, and host immunity in ambulatory participants with COVID-19. Sixty-one percent (27/44) and 50% (22/44) of participants emitted variant-specific culture-positive aerosols <10μm and <5μm, respectively, for up to 9 days after symptom onset. Aerosol culturability is significantly associated with lower neutralizing antibody titers, and suppression of transcriptomic pathways related to innate immunity and the humoral response. A nasopharyngeal Ct <17 rules-in ~40% of aerosol culture-positives and identifies those who are probably highly infectious. A parsimonious three transcript blood-based biosignature is highly predictive of infectious aerosol generation (PPV > 95%). There is considerable heterogeneity in potential infectiousness i.e., only 29% of participants were probably highly infectious (produced culture-positive aerosols <5μm at ~6 days after symptom onset). These data, which comprehensively confirm variant-specific culturable SARS-CoV-2 in aerosol, inform the targeting of transmission-related interventions and public health containment strategies emphasizing improved ventilation.

Serum bile acid measurements in women of European and South Asian ethnicity with or without gestational diabetes mellitus: A cohort study

OBJECTIVE

Investigation of serum bile acid profiles in pregnancies complicated by gestational diabetes mellitus (GDM) in a multi-ethnic cohort of women who are lean or obese.

DESIGN

Prospective cohort study.

SETTING

UK multicentre study.

POPULATION

Fasting serum from participants of European or South Asian self-reported ethnicity from the PRiDE study, between 23 and 31 weeks of gestation.

METHODS

Bile acids were measured using ultra-performance liquid chromatography-tandem mass spectrometry. Log-transformed data were analysed using linear regression in STATA/IC 15.0.

MAIN OUTCOME MEASURES

Total bile acids (TBAs), C4, fasting glucose and insulin.

RESULTS

The TBAs were 1.327-fold (1.105-1.594) increased with GDM in European women (P = 0.003). Women with GDM had 1.162-fold (1.002-1.347) increased levels of the BA synthesis marker C4 (P = 0.047). In South Asian women, obesity (but not GDM) increased TBAs 1.522-fold (1.193-1.942, P = 0.001). Obesity was associated with 1.420-fold (1.185-1.702) increased primary/secondary BA ratio (P < 0.001) related to 1.355-fold (1.140-1.611) increased primary BA concentrations (P = 0.001). TBAs were positively correlated with fasting glucose (P = 0.039) in all women, and with insulin (P = 0.001) and the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (P = 0.001) in women with GDM.

CONCLUSIONS

Serum BA homeostasis in late gestation depends on body mass index and GDM in ethnicity-specific ways. This suggests ethnicity-specific aetiologies may contribute to metabolic risk in European and South Asian women, with the relationship between BAs and insulin resistance of greater importance in European women. Further studies into ethnicity-specific precision medicine for GDM are required.

Genetically proxied low-density lipoprotein cholesterol lowering via PCSK9-inhibitor drug targets and risk of congenital malformations

AIMS

Current guidelines advise against the use of lipid-lowering drugs during pregnancy. This is based only on previous observational evidence demonstrating an association between statin use and congenital malformations, which is increasingly controversial. In the absence of clinical trial data, we aimed to use drug-target Mendelian randomization to model the potential impact of fetal LDL-lowering, overall and through PCSK9 drug targets, on congenital malformations.

METHODS AND RESULTS

Instrumental variants influencing LDL levels overall and through PCSK9-inhibitor drug targets were extracted from genome-wide association study (GWAS) summary data for LDL on 1 320 016 individuals. Instrumental variants influencing circulating PCSK9 levels (pQTLs) and liver PCSK9 gene expression levels (eQTLs) were extracted, respectively, from a GWAS on 10 186 individuals and from the genotype-tissue expression project. Gene-outcome association data was extracted from the 7th release of GWAS summary data on the FinnGen cohort (n = 342 499) for eight categories of congenital malformations affecting multiple systems. Genetically proxied LDL-lowering through PCSK9 was associated with higher odds of malformations affecting multiple systems [OR 2.70, 95% confidence interval (CI) 1.30-5.63, P = 0.018], the skin (OR 2.23, 95% CI 1.33-3.75, P = 0.007), and the vertebral, anorectal, cardiovascular, tracheo-esophageal, renal, and limb association (VACTERL) (OR 1.51, 95% CI 1.16-1.96, P = 0.007). An association was also found with obstructive defects of the renal pelvis and ureter, but this association was suggestive of horizontal pleiotropy. Lower PCSK9 pQTLs were associated with the same congenital malformations.

CONCLUSION

These data provide genetic evidence supporting current manufacturer advice to avoid the use of PCSK9 inhibitors during pregnancy.

Outcomes following major thoracoabdominal cancer resection in adults with congenital heart disease

BACKGROUND

While advances in medical and surgical management have allowed >97% of congenital heart disease (CHD) patients to reach adulthood, a growing number are presenting with non-cardiovascular malignancies. Indeed, adults with CHD are reported to face a 20% increase in cancer risk, relative to others, and cancer has become the fourth leading cause of death among this population. Surgical resection remains a mainstay in management of thoracoabdominal cancers. However, outcomes following cancer resection among these patients have not been well established. Thus, we sought to characterize clinical and financial outcomes following major cancer resections among adult CHD patients.

METHODS

The 2012-2020 National Inpatient Sample was queried for all adults (CHD or non-CHD) undergoing lobectomy, esophagectomy, gastrectomy, pancreatectomy, hepatectomy, or colectomy for cancer. To adjust for intergroup differences in baseline characteristics, entropy balancing was applied to generate balanced patient groups. Multivariable models were constructed to assess outcomes of interest.

RESULTS

Of 905,830 patients undergoing cancer resection, 1,480 (0.2%) had concomitant CHD. The overall prevalence of such patients increased from <0.1% in 2012 to 0.3% in 2012 (P for trend<0.001). Following risk adjustment, CHD was linked with greater in-hospital mortality (AOR 2.00, 95%CI 1.06-3.76), as well as a notable increase in odds of stroke (AOR 8.94, 95%CI 4.54-17.60), but no statistically significant difference in cardiac (AOR 1.33, 95%CI 0.69-2.59) or renal complications (AOR 1.35, 95%CI 0.92-1.97). Further, CHD was associated with a +2.39 day incremental increase in duration of hospitalization (95%CI +1.04-3.74) and a +$11,760 per-patient increase in hospitalization expenditures (95%CI +$4,160-19,360).

CONCLUSIONS

While a growing number of patients with CHD are undergoing cancer resection, they demonstrate inferior clinical and financial outcomes, relative to others. Novel screening, risk stratification, and perioperative management guidelines are needed for these patients to provide evidence-based recommendations for this complex and unique cohort.

Longitudinal survey of UK veterans with pre-existing mental health difficulties: mental health during the COVID-19 pandemic

INTRODUCTION

At the start of the COVID-19 pandemic, individuals with pre-existing mental health difficulties were thought to be vulnerable to mental health deterioration due to the emerging threat and the actions taken to control infection rates. Yet, there remained a paucity of research investigating changes in veteran well-being, a population facing higher rates of mental health difficulties compared with the general public. This longitudinal study aimed to investigate the mental health and well-being of UK veterans with pre-existing mental health difficulties at two time points during the COVID-19 pandemic.

METHODS

UK treatment-seeking veterans (N=121) completed an online survey administered towards the end of the first UK lockdown in June 2020 and 1 year later. Data were gathered on sociodemographic characteristics as well as psychometric measures of post-traumatic stress disorder (PTSD), common mental disorders (CMDs), anger difficulties and alcohol misuse.

RESULTS

The proportion of veterans meeting criteria of PTSD, anger and alcohol misuse remained similar across the two time points, while significantly fewer veterans met criteria for CMDs 1 year later. A notable proportion of the sample reported challenges in attending mental and physical health appointments, which was positively associated with not working and negatively associated with more COVID-19-related stressors.

CONCLUSIONS

These findings suggest that, to date, veterans with pre-existing mental health difficulties appear to demonstrate resilience as the COVID-19 pandemic progressed. However, as the pandemic continued, veterans faced significantly more COVID-19-related stressors, less social support, as well as difficulties attending health appointments.

Evaluation of hospital readmission rates as a quality metric in adult cardiac surgery

OBJECTIVE

To assess the reliability of 30-day non-elective readmissions as a quality metric for adult cardiac surgery.

BACKGROUND

Unplanned readmissions is a quality metric for adult cardiac surgery. However, its reliability in benchmarking hospitals remains under-explored.

METHODS

Adults undergoing elective isolated coronary artery bypass grafting (CABG), surgical aortic valve replacement/repair (SAVR) or mitral valve replacement/repair (MVR) were tabulated from 2019 Nationwide Readmissions Database. Multi-level regressions were developed to model the likelihood of 30-day unplanned readmissions and major adverse events (MAE). Random intercepts were estimated, and associations between hospital-specific risk-adjusted rates of readmissions and were assessed using the Pearson correlation coefficient (r).

RESULTS

Of an estimated 86 024 patients meeting study criteria across 298 hospitals, 62.6% underwent CABG, 22.5% SAVR and 14.9% MVR. Unadjusted readmission rates following CABG, SAVR and MVR were 8.4%, 9.3% and 11.8%, respectively. Unadjusted MAE rates following CABG, SAVR and MVR were 35.1%, 32.3% and 37.0%, respectively. Following adjustment, interhospital differences accounted for 4.1% of explained variance in readmissions for CABG, 7.6% for SAVR and 10.0% for MVR. There was no association between readmission rates for CABG and SAVR (r=0.10, p=0.09) or SAVR and MVR (r=0.09, p=0.1). A weak association was noted between readmission rates for CABG and MVR (r=0.20, p<0.001). There was no significant association between readmission and MAE for CABG (r=0.06, p=0.2), SAVR (r=0.04, p=0.4) and MVR (r=-0.03, p=0.6).

CONCLUSION

Our findings suggest that readmissions following adult cardiac surgery may not be an ideal quality measure as hospital factors do not appear to influence this outcome.

EASL Clinical Practice Guidelines on the management of liver diseases in pregnancy

Liver diseases in pregnancy comprise both gestational liver disorders and acute and chronic hepatic disorders occurring coincidentally in pregnancy. Whether related to pregnancy or pre-existing, liver diseases in pregnancy are associated with a significant risk of maternal and fetal morbidity and mortality. Thus, the European Association for the Study of Liver Disease invited a panel of experts to develop clinical practice guidelines aimed at providing recommendations, based on the best available evidence, for the management of liver disease in pregnancy for hepatologists, gastroenterologists, obstetric physicians, general physicians, obstetricians, specialists in training and other healthcare professionals who provide care for this patient population.

Association of opioid use disorder with outcomes of hospitalizations for acute myocardial infarction in the United States

OBJECTIVE

While Opioid Use Disorder (OUD) has been linked to inferior clinical outcomes, studies examining the clinical outcomes and readmission of OUD patients experiencing Acute Myocardial Infarction (AMI) remain lacking. The authors analyze the clinical and financial outcomes of OUD in a contemporary cohort of AMI hospitalizations.

METHODS

All non-elective adult (≥ 18 years) hospitalizations for AMI were tabulated from the 2016‒2019 Nationwide Readmissions Database using relevant International Classification of Disease codes. Patients were grouped into OUD and non-OUD cohorts. Bivariate and regression analyses were performed to identify the independent association of OUD with outcomes after non-elective admission for AMI, as well as subsequent readmission.

RESULTS

Of an estimated 3,318,257 hospitalizations for AMI meeting study criteria, 36,057 (1.1%) had a concomitant diagnosis of OUD. While OUD was not significantly associated with mortality, OUD patients experienced superior cardiovascular outcomes compared to non-OUD. However, OUD was linked to increased odds of non-cardiovascular complications, length of stay, costs, non-home discharge, and 30-day non-elective readmission.

CONCLUSIONS

Patients with OUD presented with AMI at a significantly younger age than non-OUD. While OUD appears to have a cardioprotective effect, it is associated with several markers of increased resource use, including readmission. The present findings underscore the need for a multifaceted approach to increasing social services and treatment for OUD at index hospitalization.

Rare variant contribution to cholestatic liver disease in a South Asian population in the United Kingdom

This study assessed the contribution of five genes previously known to be involved in cholestatic liver disease in British Bangladeshi and Pakistani people. Five genes (ABCB4, ABCB11, ATP8B1, NR1H4, TJP2) were interrogated by exome sequencing data of 5236 volunteers. Included were non-synonymous or loss of function (LoF) variants with a minor allele frequency < 5%. Variants were filtered, and annotated to perform rare variant burden analysis, protein structure, and modelling analysis in-silico. Out of 314 non-synonymous variants, 180 fulfilled the inclusion criteria and were mostly heterozygous unless specified. 90 were novel and of those variants, 22 were considered likely pathogenic and 9 pathogenic. We identified variants in volunteers with gallstone disease (n = 31), intrahepatic cholestasis of pregnancy (ICP, n = 16), cholangiocarcinoma and cirrhosis (n = 2). Fourteen novel LoF variants were identified: 7 frameshift, 5 introduction of premature stop codon and 2 splice acceptor variants. The rare variant burden was significantly increased in ABCB11. Protein modelling demonstrated variants that appeared to likely cause significant structural alterations. This study highlights the significant genetic burden contributing to cholestatic liver disease. Novel likely pathogenic and pathogenic variants were identified addressing the underrepresentation of diverse ancestry groups in genomic research.

A contemporary analysis of the volume-outcome relationship for extracorporeal membrane oxygenation in the United States

BACKGROUND

A paradoxical increase in mortality following extracorporeal membrane oxygenation at high-volume centers has previously been demonstrated. We examined the association between annual hospital volume and outcomes within a contemporary, national cohort of extracorporeal membrane oxygenation patients.

METHODS

All adults requiring extracorporeal membrane oxygenation for postcardiotomy syndrome, cardiogenic shock, respiratory failure, or mixed cardiopulmonary failure were identified in the 2016 to 2019 Nationwide Readmissions Database. Patients undergoing heart and/or lung transplantation were excluded. A multivariable logistic regression with hospital extracorporeal membrane oxygenation volume parametrized as restricted cubic splines was developed to characterize the risk-adjusted association between volume and mortality. The volume corresponding to the maximum of the spline (43 cases/year) was used to categorize centers as low- or high-volume.

RESULTS

An estimated 26,377 patients met the study criteria, and 48.7% were managed at high-volume hospitals. Patients at low- and high-volume hospitals had similar age, sex, and rates of elective admission. Notably, patients at high-volume hospitals less frequently required extracorporeal membrane oxygenation for postcardiotomy syndrome but more commonly for respiratory failure. After risk adjustment, high-volume hospital status was associated with reduced odds of in-hospital mortality, relative to low-volume hospitals (adjusted odds ratio 0.81, 95% confidence interval 0.78-0.97). Interestingly, patients at high-volume hospitals faced a 5.2-day increment in length of stay (95% confidence interval 3.8-6.5) and $23,500 in attributable costs (95% confidence interval 8,300-38,700).

CONCLUSION

The present study found that greater extracorporeal membrane oxygenation volume was associated with decreased mortality but higher resource use. Our findings may help inform policies regarding access to and centralization of extracorporeal membrane oxygenation care in the United States.

The impact of preconception counselling on maternal and fetal outcomes in women with chronic medical conditions: A systematic review

BACKGROUND

Beyond diabetes mellitus little data reports outcomes of women with chronic medical conditions who have received pre-conception counselling (PCC). This study aimed to perform a systematic review of the literature to evaluate evidence regarding the impact of PCC on maternal and fetal outcomes in women with chronic medical conditions aside from diabetes mellitus.

METHODS

A systematic review was conducted in accordance with PRISMA. PubMed, Cochrane, Ovid Medline and Web of Science were searched. Two reviewers screened abstracts and full texts. Inclusion criteria included studies relating to chronic medical disorders of interest published between database inception and 21^st May 2022, reporting outcomes relating to disease activity and perinatal outcomes.

RESULTS

The search yielded 11,814 results of which six met criteria for inclusion. Two papers describe the demographics of women more likely to receive PCC which included younger age, shorter disease duration, nulliparity, IVF pregnancy and higher education/job security. Two reported the effects of PCC on women's behaviour with improvements demonstrated in correct medication adherence, folic acid intake and smoking cessation. Five studies reported outcomes related to disease activity; those receiving PCC were more likely to have quiescent disease during pregnancy. Improvements in pregnancy outcomes were described including reduced rates of small for gestational age, low birth weight, preterm birth, congenital abnormality and obstetric complications.

DISCUSSION

A paucity of data exists relating to pregnancy outcomes in women with chronic medical conditions receiving PCC. Reported outcomes are favorable, supporting the routine inclusion of PCC in preparation for pregnancy in such patients.

Care Fragmentation After Hospitalization for Acute Myocardial Infarction

Care fragmentation (CF), or readmission at a nonindex hospital, has been linked to inferior clinical and financial outcomes for patients. However, its impact on patients with acute myocardial infarction (AMI) is unclear. This study investigated the prevalence and impact of CF on the outcomes of patients with AMI. All US adult (≥18 years) hospitalizations for AMI from January 2010 to November 2019 were identified using the Nationwide Readmissions Database. Patients were stratified by readmission at an index or nonindex center. Multivariable models were developed to evaluate factors associated with CF, and independent associations with mortality, complications, and resource utilization. A total of 413,819 patients with AMI requiring nonelective readmission within 30 days of discharge were included for analysis. Of these, 25.4% (n = 104,966) experienced CF. The incidence of CF increased from 2010 to 2019 (nptrend <0.001). After adjustment, patients insured by Medicaid faced higher odds of nonindex readmission. CF was associated with in-hospital mortality (adjusted odds ratio [AOR] 1.09, 95% confidence interval [CI] 1.01 to 1.18), and cardiac (AOR 1.12, 95% CI 1.03 to 1.22), respiratory (AOR 1.14, 95% CI 1.12 to 1.26), and infectious complications (AOR 1.14, 95% CI 1.07 to 1.22). Further, CF was linked to increased odds of nonhome discharge (AOR 1.18, 95% CI 1.11 to 1.24) and an additional ∼$5,000 in per-patient hospitalization costs (95% CI 4,260 to 5,100). Approximately 25% of AMI patients experienced CF, which was independently associated with excess mortality, complications, and expenditures. Given the growing national burden of cardiovascular disease, new efforts are needed to mitigate the significant clinical and financial implications of nonindex readmissions and improve value-based healthcare.

Development of obstetric-hepatology services: defining optimal care and impact of pregnancy counselling on patient experience

Objective

Prepregnancy counselling (PPC) is an important aspect of care for women with chronic liver disease (CLD) and liver transplantation (LT), yet its impact has not been well described. This study aims to assess the experience of women attending a joint obstetric-hepatology PPC clinic in a single-centre unit.

Design/methods

A retrospective questionnaire-based study in a tertiary unit within the UK where patients who attended the PPC clinic between March 2016 and July 2021 were invited to participate by filling in a questionnaire. Descriptive data and free-text content were subsequently analysed.

Results

108 women attended the PPC clinic over a 5-year period. Overall, 58/108 (54%) completed the questionnaire. Principal concerns regarding pregnancy included fears around deterioration in health (66%), maternal death (24%), pregnancy loss (66%), medication effects (60%) and disease transmission (36%). 17/58 (14%) patients felt the presence of multiple doctors was intimidating, however, perceptions improved by the end of the consultation.Overall, 44/58 (76%) respondents felt the clinic helped them reach a decision about pursuing pregnancy. Almost all respondents would recommend the clinic to others. There were no major differences in pregnancy outcomes between those that received PPC and those that did not.

Conclusion

The PPC clinic facilitates a personalised approach to care and is well received by patients with CLD/LT. It is difficult to elucidate whether attendance alone impacts on pregnancy outcomes; registry data may be better placed at addressing this important question.

GWAS meta-analysis of intrahepatic cholestasis of pregnancy implicates multiple hepatic genes and regulatory elements

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific liver disorder affecting 0.5-2% of pregnancies. The majority of cases present in the third trimester with pruritus, elevated serum bile acids and abnormal serum liver tests. ICP is associated with an increased risk of adverse outcomes, including spontaneous preterm birth and stillbirth. Whilst rare mutations affecting hepatobiliary transporters contribute to the aetiology of ICP, the role of common genetic variation in ICP has not been systematically characterised to date. Here, we perform genome-wide association studies (GWAS) and meta-analyses for ICP across three studies including 1138 cases and 153,642 controls. Eleven loci achieve genome-wide significance and have been further investigated and fine-mapped using functional genomics approaches. Our results pinpoint common sequence variation in liver-enriched genes and liver-specific cis-regulatory elements as contributing mechanisms to ICP susceptibility.

A multi-centered trial investigating gestational treatment with ursodeoxycholic acid compared to metformin to reduce effects of diabetes mellitus (GUARD): a randomized controlled trial protocol

BACKGROUND

Each year in the UK, approximately 35,000 women develop gestational diabetes mellitus (GDM). The condition increases the risk of obstetric and neonatal complications for mother and child, including preeclampsia, preterm birth, and large for gestational age babies. Biochemical consequences include maternal hyperglycemia, neonatal hypoglycemia, and dyslipidemia. Metformin is the most commonly used firstline pharmacological treatment. However, there are concerns about its widespread use during pregnancy, due to its limited efficacy and potential safety concerns. Therefore, there is a need for additional therapies that improve both maternal-fetal glucose and lipid metabolism. Ursodeoxycholic acid (UDCA) is not currently used for treatment for GDM. However, it can improve glucose control in type 2 diabetes, and it improves fetal lipid profiles in gestational cholestasis. Consequentially, it is hypothesized that treatment with UDCA for women with GDM may improve both maternal metabolism and neonatal outcomes. The primary outcome of this trial is to assess the efficacy of UDCA compared with metformin to improve glucose levels in women with GDM.

METHODS

The trial is a two-armed, open-label, multi-center, randomized controlled trial. Women are eligible if they have been diagnosed with GDM by an oral glucose tolerance test between 24 + 0 and 30 + 6 weeks' gestation, and if they require pharmacological intervention. In total, 158 pregnant women will be recruited across seven NHS Trusts in England and Wales. Women who consent will be recruited and randomized to either metformin or UDCA, which will be taken daily until the birth of their baby. Maternal and neonatal blood samples will be taken to evaluate the impact of the treatments on maternal glucose control, and maternal and neonatal lipid metabolism. Maternal and fetal outcomes will be evaluated, and acceptability of UDCA compared with metformin will be assessed.

DISCUSSION

This trial has the potential to identify a potential new treatment for women with GDM. If successful, a future large multi-center trial will be designed to investigate where decisions can be personalized to identify which women will respond more effectively to UDCA than alternatives to improve maternal and baby outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04407650.

Pregnancy-Associated Liver Diseases

The liver disorders unique to pregnancy include hyperemesis gravidarum, intrahepatic cholestasis of pregnancy, acute fatty liver of pregnancy, and preeclampsia-associated hepatic impairment, specifically hemolysis, elevated liver enzymes, and low platelet count syndrome (HELLP). Their importance lies in the significant maternal and fetal/neonatal morbidity and mortality. Expeditious diagnosis and clinical evaluation is critical to ensure timely, appropriate care and minimize risks to the pregnant woman and her fetus/baby. A multidisciplinary approach is essential, including midwives, maternal-fetal-medicine specialists, anesthetists, neonatologists, and hepatologists.

Interactions of Fungi and Algae from the Greenland Ice Sheet

Heavily pigmented glacier ice algae Ancylonema nordenskiöldii and Ancylonema alaskanum (Zygnematophyceae, Streptophyta) reduce the bare ice albedo of the Greenland Ice Sheet, amplifying melt from the largest cryospheric contributor to eustatic sea-level rise. Little information is available about glacier ice algae interactions with other microbial communities within the surface ice environment, including fungi, which may be important for sustaining algal bloom development. To address this substantial knowledge gap and investigate the nature of algal-fungal interactions, an ex situ co-cultivation experiment with two species of fungi, recently isolated from the surface of the Greenland Ice Sheet (here proposed new species Penicillium anthracinoglaciei Perini, Frisvad and Zalar, Mycobank (MB 835602), and Articulospora sp.), and the mixed microbial community dominated by glacier ice algae was performed. The utilization of the dark pigment purpurogallin carboxylic acid-6-O-β-D-glucopyranoside (C₁₈H₁₈O₁₂) by the two fungi was also evaluated in a separate experiment. P. anthracinoglaciei was capable of utilizing and converting the pigment to purpurogallin carboxylic acid, possibly using the sugar moiety as a nutrient source. Furthermore, after 3 weeks of incubation in the presence of P. anthracinoglaciei, a significantly slower decline in the maximum quantum efficiency (F_v/F_m, inverse proxy of algal stress) in glacier ice algae, compared to other treatments, was evident, suggesting a positive relationship between these species. Articulospora sp. did uptake the glycosylated purpurogallin, but did not seem to be involved in its conversion to aglycone derivative. At the end of the incubation experiments and, in conjunction with increased algal mortality, we detected a substantially increasing presence of the zoosporic fungi Chytridiomycota suggesting an important role for them as decomposers or parasites of glacier ice algae.

Association of Frailty with clinical and financial outcomes of Esophagectomy hospitalizations in the US

Background

Frailty, defined as impaired physiologic reserve and function, has been associated with inferior results after surgery. Using a coding-based tool, we examined the clinical and financial impact of frailty on outcomes following esophagectomy.

Methods

Adults undergoing elective esophagectomy were identified using the 2010–2018 Nationwide Readmissions Database. Using the binary Johns Hopkins Adjusted Clinical Groups frailty indicator, patients were classified as frail or nonfrail. Multivariable regression models were used to evaluate the association of frailty with in-hospital mortality, complications, hospitalization duration, costs, nonhome discharge, and unplanned 30-day readmission.

Results

Of 45,361 patients who underwent esophagectomy, 18.7% were considered frail. Most frail patients were found to have diagnoses of malnutrition (70%) or weight loss (15%) at the time of surgery. After adjustment, frailty was associated with increased risk of in-hospital mortality (adjusted odds ratio 1.67, 95% confidence interval 1.29–2.16) and overall complications (adjusted odds ratio 1.57, 95% confidence interval 1.44–1.71). Frailty conferred a 5.6-day increment in length of stay (95% confidence interval 4.94–6.45) and an additional $19,900 hospitalization cost (95% confidence interval $16,700–$23,100). Frail patients had increased odds of nonhome discharge (adjusted odds ratio 1.53, 95% confidence interval 1.35–1.75) as well as unplanned 30-day readmissions (adjusted odds ratio 1.17, 95% confidence interval 1.02–1.34).

Conclusion

Frailty, as detected by an administrative tool, is associated with worse clinical and financial outcomes following esophagectomy. The inclusion of standardized assessment of frailty in risk models may better inform patient selection and shared decision-making prior to operative intervention.

Sulfated Progesterone Metabolites That Enhance Insulin Secretion via TRPM3 Are Reduced in Serum From Women With Gestational Diabetes Mellitus

Serum progesterone sulfates were evaluated in the etiology of gestational diabetes mellitus (GDM). Serum progesterone sulfates were measured using ultra-performance liquid chromatography-tandem mass spectrometry in four patient cohorts: 1) the Hyperglycemia and Adverse Pregnancy Outcomes study; 2) London-based women of mixed ancestry and 3) U.K.-based women of European ancestry with or without GDM; and 4) 11-13 weeks pregnant women with BMI ≤25 or BMI ≥35 kg/m2 with subsequent uncomplicated pregnancies or GDM. Glucose-stimulated insulin secretion (GSIS) was evaluated in response to progesterone sulfates in mouse islets and human islets. Calcium fluorescence was measured in HEK293 cells expressing transient receptor potential cation channel subfamily M member 3 (TRPM3). Computer modeling using Molecular Operating Environment generated three-dimensional structures of TRPM3. Epiallopregnanolone sulfate (PM5S) concentrations were reduced in GDM (P < 0.05), in women with higher fasting plasma glucose (P < 0.010), and in early pregnancy samples from women who subsequently developed GDM with BMI ≥35 kg/m2 (P < 0.05). In islets, 50 µmol/L PM5S increased GSIS by at least twofold (P < 0.001); isosakuranetin (TRPM3 inhibitor) abolished this effect. PM5S increased calcium influx in TRPM3-expressing HEK293 cells. Computer modeling and docking showed identical positioning of PM5S to the natural ligand in TRPM3. PM5S increases GSIS and is reduced in GDM serum. The activation of GSIS by PM5S is mediated by TRPM3 in both mouse and human islets.

Exploring the impact of COVID-19 and restrictions to daily living as a result of social distancing within veterans with pre-existing mental health difficulties

INTRODUCTION

Data are emerging showing the adverse consequences on mental health of the general public due to the COVID-19 pandemic. Little is known about the needs of veterans with pre-existing mental health difficulties during the COVID-19 pandemic.

METHODS

Data were collected through a cross-sectional online survey from a randomly selected sample (n=1092) of military veterans who have sought help for mental health difficulties from a veteran-specific UK-based charity. The response rate was 25.2% (n=275). Participants were asked to complete a range of standardised mental health outcomes (post-traumatic stress disorder (PTSD): Post-traumatic Stress Disorder Checklist, common mental health difficulties (CMDs): 12-Item General Health Questionnaire, difficulties with anger: 5-Item Dimensions of Anger Reactions-Revised and alcohol misuse: Alcohol Use Disorders Identification Test) and endorse a list of potential stressors related to changes to daily life resulting from COVID-19. Regression analyses were fitted to explore predictors of mental health severity.

RESULTS

It was observed that symptoms of common mental disorder and PTSD (69.3% and 65.0%, respectively) were the most commonly reported to have been exacerbated by the pandemic. Lack of social support and reporting increasing numbers of stressors related to COVID-19 were consistently associated with increasing severity of a range of mental health difficulties.

CONCLUSIONS

Our findings suggest veterans who had pre-existing mental health difficulties prior to the outbreak of COVID-19 may be at increased risk of experiencing CMDs as a result of the pandemic. Intervening to improve levels of social support and offering practical guidance to better manage any additional stressors relating to the pandemic may provide strategies to help reduce the burden of mental health symptoms.

Association of Maternal Thyroid Function with Gestational Hypercholanemia

Background: High bile acid concentration is associated with adverse perinatal outcomes (i.e., stillbirth and preterm birth) and experimental studies indicate that thyroid hormone regulates bile acid metabolism, but this has not yet been translated to clinical data in pregnant women. We aim to explore the association of thyroid function with bile acid concentrations and the risk of gestational hypercholanemia. Methods: This study comprised 68,016 singleton pregnancies without known thyroid or hepatobiliary diseases before pregnancy and thyroid medication based on a prospective cohort. Thyroid function and serum total bile acid (TBA) were routinely screened in both early (9-13 weeks) and late pregnancy (32-36 weeks). Hypercholanemia was defined as serum TBA concentration ≥10 μmol/L. Multiple linear regression models and multiple logistic regression models were performed. Results: A higher free thyroxine (fT4) during both early or late pregnancy was associated with a higher TBA concentration and a higher risk of hypercholanemia (all p < 0.01). A higher thyrotropin (TSH) in early pregnancy was associated with a higher TBA concentration in early pregnancy (p = 0.0155), but with a lower TBA concentration during later pregnancy (p < 0.0001), and there was no association of TSH with hypercholanemia. Overt hyperthyroidism in late pregnancy was associated with a 2.12-fold higher risk of hypercholanemia ([confidence interval; CI 1.12-4.03], p = 0.021) and subclinical hyperthyroidism during later pregnancy was associated with a 1.5-fold higher risk of hypercholanemia ([CI 1.14-1.97], p = 0.0034). Sensitivity analyses indicated that a high fT4 throughout pregnancy was associated with a higher risk of hypercholanemia rather than only in early or late pregnancy. Conclusions: A higher fT4 concentration during either early or late pregnancy, but not the TSH concentration, is associated with higher TBA and a higher risk of gestational hypercholanemia. Furthermore, hyperthyroidism during pregnancy could be a novel risk factor for hypercholanemia.

Measurement of the cardiac time intervals of the fetal ECG utilising a computerised algorithm: A retrospective observational study

Objective

Establish whether the reliable measurement of cardiac time intervals of the fetal ECG can be automated and to address whether this approach could be used to investigate large datasets.

Design

Retrospective observational study.

Setting

Teaching hospitals in London UK, Nottingham UK and New York USA.

Participants

Singleton pregnancies with no known fetal abnormality.

Methods

Archived fetal ECG's performed using the MonicaAN24 monitor. A single ECG (PQRST) complex was generated from 5000 signal-averaged beats and electrical cardiac time intervals measured in an automated way and manually.

Main Outcome measure

Validation of a newly developed algorithm to measure the cardiac time intervals of the fetal ECG.

Results

188/236 (79.7%) subjects with fECGs of suitable signal:noise ratio were included for analysis comparing manual with automated measurement. PR interval was measured in 173/188 (92%), QRS complex in 170/188 (90%) and QT interval in 123/188 (65.4%). PR interval was 107.6 (12.07) ms [mean(SD)] manual vs 109.11 (14.7) ms algorithm. QRS duration was 54.72(6.35) ms manual vs 58.34(5.73) ms algorithm. QT-interval was 268.93 (21.59) ms manual vs 261.63 (36.16) ms algorithm. QTc was 407.5(32.71) ms manual vs 396.4 (54.78) ms algorithm. The QRS-duration increased with gestational age in both manual and algorithm measurements.

Conclusion

Accurate measurement of fetal ECG cardiac time intervals can be automated with potential application to interpretation of larger datasets.

Termination of wanted pregnancy and suicidal ideation in hyperemesis gravidarum: A mixed methods study

Background

Difficulty accessing medication and poor patient experience have been implicated as risk factors for termination of pregnancy and suicidal ideation in women with hyperemesis gravidarum. We aimed to gain further insight into these factors in order to further inform and improve patient care.

Methods

We performed a sub-analysis on quantitative data generated through a UK-wide survey of 5071 participants. A qualitative analysis of free text comments was performed using an inductive thematic approach.

Results

41.2% % of women taking prescribed medications had to actively request them. ‘Extremely poor’ or ‘poor’ experiences were described in 39.4% and 30.0% of participants in primary and secondary care respectively. Protective factors for termination of pregnancy and suicidal ideation include holistic support from family, friends and healthcare providers.

Conclusion

Optimal care in hyperemesis gravidarum should incorporate timely access to pharmacotherapy, assessment of mental health, consideration of referral to specialist services and care being delivered in a compassionate manner.

Continued Relevance of Minimum Volume Standards for Elective Esophagectomy: A National Perspective

BACKGROUND

Despite minimum volume recommendations, the majority of esophagectomies are performed at centers with fewer than 20 annual cases. The present study examined the impact of institutional esophagectomy volume on in-hospital mortality, complications and resource use following esophageal resection.

METHODS

The 2010-2018 Nationwide Readmissions Database was queried to identify all adult patients undergoing esophagectomy for malignancy. Hospitals were categorized as high-volume (HVH) if performing at least 20 esophagectomies annually, and low-volume (LVH) if fewer. Multivariable models were developed to study the impact of volume on outcomes of interest which included in-hospital mortality, complications, duration of hospitalization (LOS), inflation adjusted costs, readmissions, and non-home discharge.

RESULTS

Of an estimated 23,176 hospitalizations, 45.6% occurred at HVH. Incidence of esophagectomy increased significantly along with median institutional case load over the study period, while the proportion on hospitals considered HVH remained steady at approximately 7.4%. After adjusting for relevant patient and hospital characteristics, HVH was associated with decreased mortality (AOR=0.65), LOS (β=-1.83 days), pneumonia (AOR=0.69), prolonged ventilation (AOR=0.50), sepsis (AOR=0.80), and tracheostomy (AOR=0.66), but increased odds of non-home discharge (AOR=1.56, all P<0.01), with LVH as reference.

CONCLUSIONS

Many clinical outcomes of esophagectomy are improved with no increment in costs when performed at centers with an annual caseload of at least 20, as recommended by patient advocacy organizations. These findings suggest that centralization of esophageal resections to high-volume centers may be congruent with value-based care models.

The BACH project protocol: an international multicentre total Bile Acid Comparison and Harmonisation project and sub-study of the TURRIFIC randomised trial

OBJECTIVES

Multicentre international trials relying on diagnoses derived from biochemical results may overlook the importance of assay standardisation from the participating laboratories. Here we describe a study protocol aimed at harmonising results from total bile acid determinations within the context of an international randomised controlled Trial of two treatments, URsodeoxycholic acid and RIFampicin, for women with severe early onset Intrahepatic Cholestasis of pregnancy (TURRIFIC), referred to as the Bile Acid Comparison and Harmonisation (BACH) study, with the aims of reducing inter-laboratory heterogeneity in total bile acid assays.

METHODS

We have simulated laboratory data to determine the feasibility of total bile acid recalibration using a reference set of patient samples with a consensus value approach and subsequently used regression-based techniques to transform the data.

RESULTS

From these simulations, we have demonstrated that mathematical recalibration of total bile acid results is plausible, with a high probability of successfully harmonising results across participating laboratories.

CONCLUSIONS

Standardisation of bile acid results facilitates the commutability of laboratory results and collation for statistical analysis. It may provide the momentum for broader application of the described techniques in the setting of large-scale multinational clinical trials dependent on results from non-standardised assays.

Ursodeoxycholic acid in intrahepatic cholestasis of pregnancy: a systematic review and individual participant data meta-analysis

BACKGROUND

Ursodeoxycholic acid is commonly used to treat intrahepatic cholestasis of pregnancy, yet its largest trial detected minimal benefit for a composite outcome (stillbirth, preterm birth, and neonatal unit admission). We aimed to examine whether ursodeoxycholic acid affects specific adverse perinatal outcomes.

METHODS

In this systematic review and individual participant data meta-analysis, we searched PubMed, Web of Science, Embase, MEDLINE, CINAHL, Global Health, MIDIRS, and Cochrane without language restrictions for relevant articles published between database inception, and Jan 1, 2020, using search terms referencing intrahepatic cholestasis of pregnancy, ursodeoxycholic acid, and perinatal outcomes. Eligible studies had 30 or more study participants and reported on at least one individual with intrahepatic cholestasis of pregnancy and bile acid concentrations of 40 μmol/L or more. We also included two unpublished cohort studies. Individual participant data were collected from the authors of selected studies. The primary outcome was the prevalence of stillbirth, for which we anticipated there would be insufficient data to achieve statistical power. Therefore, we included a composite of stillbirth and preterm birth as a main secondary outcome. A mixed-effects meta-analysis was done using multi-level modelling and adjusting for bile acid concentration, parity, and multifetal pregnancy. Individual participant data analyses were done for all studies and in different subgroups, which were produced by limiting analyses to randomised controlled trials only, singleton pregnancies only, or two-arm studies only. This study is registered with PROSPERO, CRD42019131495.

FINDINGS

The authors of the 85 studies fulfilling our inclusion criteria were contacted. Individual participant data from 6974 women in 34 studies were included in the meta-analysis, of whom 4726 (67·8%) took ursodeoxycholic acid. Stillbirth occurred in 35 (0·7%) of 5097 fetuses among women with intrahepatic cholestasis of pregnancy treated with ursodeoxycholic acid and in 12 (0·6%) of 2038 fetuses among women with intrahepatic cholestasis of pregnancy not treated with ursodeoxycholic acid (adjusted odds ratio [aOR] 1·04, 95% CI 0·35-3·07; p=0·95). Ursodeoxycholic acid treatment also had no effect on the prevalence of stillbirth when considering only randomised controlled trials (aOR 0·29, 95% CI 0·04-2·42; p=0·25). Ursodeoxycholic acid treatment had no effect on the prevalence of the composite outcome in all studies (aOR 1·28, 95% CI 0·86-1·91; p=0·22), but was associated with a reduced composite outcome when considering only randomised controlled trials (0·60, 0·39-0·91; p=0·016).

INTERPRETATION

Ursodeoxycholic acid treatment had no significant effect on the prevalence of stillbirth in women with intrahepatic cholestasis of pregnancy, but our analysis was probably limited by the low overall event rate. However, when considering only randomised controlled trials, ursodeoxycholic acid was associated with a reduction in stillbirth in combination with preterm birth, providing evidence for the clinical benefit of antenatal ursodeoxycholic acid treatment.

FUNDING

Tommy's, the Wellcome Trust, ICP Support, and the National Institute for Health Research.

Clinical and Financial Outcomes of Necrotizing Soft-Tissue Infections in Safety-Net Hospitals

Background Prior work has demonstrated inferior outcomes for a multitude of medical and surgical conditions at hospitals with high burdens of underinsured patients (safety-net). The present study aimed to evaluate trends in incidence, clinical outcomes and resource utilization in the surgical management of necrotizing soft-tissue infections (NSTI) at safety-net hospitals. Materials and methods Adults requiring surgical debridement/amputation following NSTI-related hospitalizations were identified in the 2005-2018 National Inpatient Sample. Safety-net status (SNH) was assigned to institutions in the top tertile for annual proportion of underinsured patients. Logistic multivariable regression was utilized to evaluate the association of SNH with mortality, hospitalization duration (LOS), costs and discharge disposition. Results Of an estimated 212,692 patients, 76,719 (36.1%) were managed at SNH. The annual incidence of NSTI admissions increased overall while associated mortality declined. After adjustment, SNH status was associated with greater odds of mortality (adjusted odds ratios: 1.14, 95% CI: 1.03-1.26), LOS (β: +1.8 d, 95% CI: 1.3-2.2) and costs (β: +$4,400, 95% CI: 2,900-5,800). SNH patients had similar rates of amputation but lower likelihood of care facility or home health discharge. Conclusion With a rising incidence and overall reduction in mortality, safety-net hospitals persistently exhibit greater mortality and resource use for surgical NSTI admissions. Variation in access, disease presentation and timeliness of operative intervention may explain the observed findings.

Palliative Care for Extracorporeal Life Support: Insights From the National Inpatient Sample

BACKGROUND

Providing temporary cardiopulmonary support, extracorporeal membrane oxygenation (ECMO) carries a high risk of mortality. Palliative care (PC) may facilitate a patient-centered approach to end-of-life care in order to aid symptom management and provide psychosocial support to families. The present study aimed to identify factors associated with PC consultation and its impact on resource utilization in ECMO.

STUDY DESIGN

All adults placed on ECMO at a PC capable center were identified in the 2006-2017 National Inpatient Sample. Indications for ECMO were identified using diagnosis codes and classified into postcardiotomy syndrome, respiratory failure, cardiogenic shock, mixed cardiopulmonary failure, and transplant related.

RESULTS

Of 41 122 patients undergoing ECMO, 20 514 (49.9%) died in the same hospitalization. Of those, 3951 (19.3%) received a PC consult. Use of PC consults increased significantly from 5.5% in 2006 to 22.8% in 2017 (nptrend<.001). After multivariable risk adjustment, PC consults did not affect costs (β: -$7341, 95% CI: -22 572 to +7888) or duration of hospitalizations (β: -.37 days, 95% CI: -2.76 to +2.02).

CONCLUSION

Utilization of PC does not appear to negatively influence resource utilization among non-survivors of ECMO. Increased adaptation of PC in ECMO may improve end-of-life care, a factor that deserves future study.

717 The Introduction of a Discharge Letter Proforma For Hip Fracture Patients Improves Compliance with VTE Prophylaxis Prescription on Discharge: A Closed Loop Audit

Introduction

Venous thromboembolism (VTE) is a significant cause of morbidity and mortality in inpatients; with those undergoing lower limb surgery at particularly high risk. NICE recommends that Low Molecular Weight Heparin (LMWH) or Fondaparinux should be used for VTE prophylaxis for one month following hip fracture. Our local policy is to prescribe Dalteparin for 30 days following surgery.

Method

A closed loop audit of VTE prophylaxis on discharge for 193 patients with hip fractures was performed. The first audit cycle established whether VTE prophylaxis was being prescribed in line with departmental policy. Following this, a template discharge letter was introduced which included a prompt for appropriate prescription of VTE prophylaxis.

Results

Initially, data for 93 consecutive patients was collected. It was found that 13% had not received VTE prophylaxis in line with guidelines. Of these, six patients had no documented contraindication or alternative prophylaxis prescribed. Results were disseminated locally.

After introduction of the template discharge letter, data for 100 consecutive patients was collected. Re-audit showed a marked improvement in adherence to local policy with 95% of patients now receiving appropriate VTE prophylaxis on discharge.

Conclusions

Introduction of a template discharge letter prompts the documentation of contraindications to prophylaxis and improves compliance with local policy.

Fetal cardiac dysfunction in intrahepatic cholestasis of pregnancy is associated with elevated serum bile acid concentrations

BACKGROUND & AIMS

Intrahepatic cholestasis of pregnancy (ICP) is associated with an increased risk of stillbirth. This study aimed to assess the relationship between bile acid concentrations and fetal cardiac dysfunction in patients with ICP who were or were not treated with ursodeoxycholic acid (UDCA).

METHODS

Bile acid profiles and NT-proBNP, a marker of ventricular dysfunction, were assayed in umbilical venous serum from 15 controls and 76 ICP cases (36 untreated, 40 UDCA-treated). Fetal electrocardiogram traces were obtained from 43 controls and 48 ICP cases (26 untreated, 22 UDCA-treated). PR interval length and heart rate variability (HRV) parameters were measured in 2 behavioral states (quiet and active sleep).

RESULTS

In untreated ICP, fetal total serum bile acid (TSBA) concentrations (r = 0.49, p = 0.019), hydrophobicity index (r = 0.20, p = 0.039), glycocholate concentrations (r = 0.56, p = 0.007) and taurocholate concentrations (r = 0.44, p = 0.039) positively correlated with fetal NT-proBNP. Maternal TSBA (r = 0.40, p = 0.026) and alanine aminotransferase (r = 0.40, p = 0.046) also positively correlated with fetal NT-proBNP. There were no significant correlations between maternal or fetal serum bile acid concentrations and fetal HRV parameters or NT-proBNP concentrations in the UDCA-treated cohort. Fetal PR interval length positively correlated with maternal TSBA in untreated (r = 0.46, p = 0.027) and UDCA-treated ICP (r = 0.54, p = 0.026). Measures of HRV in active sleep and quiet sleep were significantly higher in untreated ICP cases than controls. HRV values in UDCA-treated cases did not differ from controls.

CONCLUSIONS

Elevated fetal and maternal serum bile acid concentrations in untreated ICP are associated with an abnormal fetal cardiac phenotype characterized by increased NT-proBNP concentration, PR interval length and HRV. UDCA treatment partially attenuates this phenotype.

LAY SUMMARY

The risk of stillbirth in intrahepatic cholestasis of pregnancy (ICP) is linked to the level of bile acids in the mother which are thought to disrupt the baby's heart rhythm. We found that babies of women with untreated ICP have abnormally functioning hearts compared to those without ICP, and the degree of abnormality is closely linked to the level of harmful bile acids in the mother and baby's blood. Babies of women with ICP who received treatment with the drug UDCA do not have the same level of abnormality in their hearts, suggesting that UDCA could be a beneficial treatment in some ICP cases, although further clinical trials are needed to confirm this.

The Impact of Expedited Discharge on 30-Day Readmission Following Lung Resection: A National Study

BACKGROUND

Expedited discharge (within 24 hours) following lung resection has received scrutiny due to concerns for higher readmissions and paradoxically increased costs. The present study examined the impact of expedited discharge on hospitalization costs and unplanned readmissions using a nationally-representative sample. In addition, we sought to determine inter-hospital practice variation.

METHODS

Adults undergoing elective lobar or sublobar resection were identified using the 2016-2018 Nationwide Readmissions Database, while those with postoperative duration of hospitalization >5 days or experienced any perioperative complication, were excluded. Patients were classified as Expedited if postoperative hospitalization was 0 or 1 day and otherwise as Routine. Inverse probability of treatment weighing was utilized to adjust for intergroup differences. Hospitals were ranked according to risk-adjusted early discharge rates. Multivariable regression models were developed to assess the association of expedited discharge on nonelective 30-day readmissions as well as associated mortality and costs.

RESULTS

Of an estimated 84,152 patients, 13,834 (16.4%) comprised the Expedited group. Compared to Routine, Expedited were younger, less likely to have chronic obstructive pulmonary disease and undergo open procedures. Following adjustment, early discharge was associated with lower incremental costs (β coefficient: -$3.6K, 95%CI: -4.4 - -2.8) as well as similar readmissions (odds ratio: 0.89, 95%CI: 0.70 - 1.13) and related-mortality. Nearly half (48.1%) of all hospitals performed zero early discharges.

CONCLUSIONS

Expedited discharge following lung resection is a feasible management strategy and is associated with decreased costs and similar readmission risk compared to the norm. Select individuals should be strongly considered for expedited discharge following lung resection.

Trends and Outcomes of Surgical Re-exploration Following Cardiac Operations in the United States

BACKGROUND

Surgical re-exploration following cardiac surgery has been associated with increased in-hospital complications and mortality in limited series. The present study examined trends in reoperation and its impact on clinical outcomes and resource use in a nationally-representative cohort. We sought to determine patient and hospital factors associated with re-exploration and reoperative mortality, defined as failure-to-rescue-surgical (FTR-S).

METHODS

Adult hospitalizations entailing cardiac operations (coronary artery bypass and/or valve) were identified using the 2005-2018 National Inpatient Sample. Procedures were tabulated using International Classification of Diseases codes. Hospitals were ranked into tertiles according to risk-adjusted mortality, with the lowest stratified as high-performing. Multivariable regression models examined factors associated with re-exploration as well as clinical outcomes including FTR-S and resource utilization.

RESULTS

Of an estimated 3,490,245 hospitalizations, 78,003 (2.23%) required re-exploration with decreasing incidence over time. Valvular procedures, preoperative intra-aortic balloon pump and liver disease were associated with greater likelihood of re-exploration. Reoperation was associated with increased odds of mortality (adjusted odds ratio (AOR): 3.86, 95%CI: 3.61-4.12), perioperative complications and resource utilization. Increasing time from index operation to re-exploration was associated with higher odds of mortality (AOR:1.10/day, 95%CI: 1.07-1.12). High-performing hospitals were associated with lower odds of re-exploration (AOR: 0.88, 95%CI: 0.82-0.95) and FTR-S (AOR: 0.29, 95%CI: 0.23-0.35).

CONCLUSIONS

Surgical re-exploration following cardiac surgery has declined over time. High performing hospitals demonstrated lower rates of re-exploration and subsequent failure-to-rescue. Although unable to identify specific practices, our study highlights the presence of significant variation in takeback rates and further study of underlying factors is warranted.

Re-evaluating diagnostic thresholds for intrahepatic cholestasis of pregnancy: case-control and cohort study

OBJECTIVE

To determine the optimal total serum bile acid (TSBA) threshold and sampling time for accurate intrahepatic cholestasis of pregnancy (ICP) diagnosis.

DESIGN

Case-control, retrospective cohort studies.

SETTING

Antenatal clinics, clinical research facilities.

POPULATION

Women with ICP or uncomplicated pregnancies.

METHODS

Serial TSBA measurements were performed pre-/postprandially in 42 women with ICP or uncomplicated pregnancy. Third-trimester non-fasting TSBA reference ranges were calculated from 561 women of black, south Asian and white ethnicity. Rates of adverse perinatal outcomes for women with ICP but peak non-fasting TSBA below the upper reference range limit were compared with those in healthy populations.

MAIN OUTCOME MEASURES

Sensitivity and specificity of common TSBA thresholds for ICP diagnosis, using fasting and postprandial TSBA. Calculation of normal reference ranges of non-fasting TSBA.

RESULTS

Concentrations of TSBA increased markedly postprandially in all groups, with overlap between healthy pregnancy and mild ICP (TSBA <40 μmol/l). The specificity of ICP diagnosis was higher when fasting, but corresponded to <30% sensitivity for diagnosis of mild disease. Using TSBA ≥40 μmol/l to define severe ICP, fasting measurements identified 9% (1/11), whereas non-fasting measurements detected over 91% with severe ICP. The highest upper limit of the non-fasting TSBA reference range was 18.3 µmol/l (95% confidence interval: 15.0-35.6 μmol/l). A re-evaluation of published ICP meta-analysis data demonstrated no increase in spontaneous preterm birth or stillbirth in women with TSBA <19 µmol/l.

CONCLUSIONS

Postprandial TSBA levels are required to identify high-risk ICP pregnancies (TSBA ≥40 μmol/l). The postprandial rise in TSBA in normal pregnancy indicates that a non-fasting threshold of ≥19 µmol/l would improve diagnostic accuracy.

TWEETABLE ABSTRACT

Non-fasting bile acids improve the diagnostic accuracy of intrahepatic cholestasis of pregnancy diagnosis.

Association of Hospital Safety Net Status With Outcomes and Resource Use for Extracorporeal Membrane Oxygenation in the United States

PURPOSE

Safety net hospitals (SNH) have been associated with inferior surgical outcomes and increased resource use. Utilization and outcomes for extracorporeal membrane oxygenation (ECMO), a rescue modality for patients with respiratory or cardiac failure, may vary by safety net status. We hypothesized SNH to be associated with inferior outcomes and costs of ECMO in a national cohort.

MATERIALS AND METHODS

The 2008-2017 National Inpatient Sample was queried for ECMO hospitalizations and safety net hospitals were identified. Multivariable regression was used to perform risk-adjusted comparisons of mortality, complications and resource utilization at safety net and non-safety net hospitals.

RESULTS

Of 36,491 ECMO hospitalizations, 28.2% were at SNH. On adjusted comparison SNH was associated with increased odds of mortality (AOR: 1.23), tracheostomy use (AOR: 1.51), intracranial hemorrhage (AOR: 1.39), as well as infectious complications (AOR: 1.21, all P < .05), with NSNH as reference. SNH was also associated with increased hospitalization duration (β=+4.5 days) and hospitalization costs (β=+$32,880, all P < .01).

CONCLUSIONS

We have found SNH to be associated with inferior survival, increased complications, and higher costs compared to NSNH. These disparate outcomes warrant further studies examining systemic and hospital-level factors that may impact outcomes and resource use of ECMO at SNH.

ENDOCRINOLOGY IN PREGNANCY: Metabolic impact of bile acids in gestation

Bile acids are lipid-solubilising molecules that also regulate metabolic processes. Farnesoid X receptor (FXR) and Takeda G-protein coupled receptor 5 (TGR5) are two bile acid receptors with key metabolic roles. FXR regulates bile acid synthesis in the liver and influences bile acid uptake in the intestine. TGR5 is mainly involved in regulation of signalling pathways in response to bile acid uptake in the gut and therefore prandial response. Both FXR and TGR5 have potential as therapeutic targets for disorders of glucose and/or lipid homeostasis. Gestation is also known to cause small increases in bile acid concentrations, but physiological hypercholanaemia of pregnancy is usually not sufficient to cause any clinically relevant effects. This review focuses on how gestation alters bile acid homeostasis, which can become pathological if the elevation of maternal serum bile acids is more marked than physiological hypercholanaemia, and on the influence of FXR and TGR5 function in pregnancy on glucose and lipid metabolism. This will be discussed with reference to two gestational disorders: intrahepatic cholestasis of pregnancy (ICP), a disease where bile acids are pathologically elevated, and gestational diabetes mellitus (GDM), characterised by hyperglycaemia during pregnancy.

Management of pregnancy in women with cirrhosis

Although pregnancy is rare in women with cirrhosis, it is increasingly prevalent in an era of modern assisted conception techniques and improved awareness, monitoring and management of underlying liver disease. After overcoming the difficulties of subfertility and becoming pregnant, women undergo a 'high-risk' pregnancy which can be complicated by variceal haemorrhage (≤50%) and hepatic decompensation (≤25%). Management of these complications are similar to non-pregnant individuals. However, there are a few caveats to consider. These pregnancies are associated with adverse maternal and foetal outcomes, such as mortality (0%-8%) and prematurity (19%-67%) in the newborn, and mortality (0%-14%), pregnancy-induced hypertension (5%-22%) and post-partum haemorrhage (5%-45%) in the mother. Pre-pregnancy counselling, use of predictive scores and appropriate variceal screening during pregnancy can stratify patients and improve outcomes. This review focusses on the complications that can occur during pregnancy in women with cirrhosis.

Nuclear receptors, gestational metabolism and maternal metabolic disorders

Normal pregnancy is characterised by a gradual alteration in metabolism that results in elevated serum bile acids, dyslipidaemia and impaired glucose tolerance in the third trimester. Nuclear receptors play important roles in regulating metabolic pathways that influence alterations in these parameters. There is evidence for altered function of FXR and LXR in gestation; these nuclear receptors play an integral role in bile acid and lipid homeostasis. There is some evidence for influence of clock genes in late pregnancy metabolic changes, and this may be linked to alterations in placental gene expression and function, thereby influencing fetal growth. This article will review the current data from human studies and investigation of animal models to illustrate the role of nuclear receptors (namely LXR, FXR, PPARs and clock genes) in gestational alterations in metabolism and the ways this may influence susceptibility to metabolic disorders of pregnancy such as gestational diabetes mellitus and intrahepatic cholestasis of pregnancy.

A multi-centre, open label, randomised, parallel-group, superiority Trial to compare the efficacy of URsodeoxycholic acid with RIFampicin in the management of women with severe early onset Intrahepatic Cholestasis of pregnancy: the TURRIFIC randomised trial

BACKGROUND

Severe early onset (less than 34 weeks gestation) intrahepatic cholestasis of pregnancy (ICP) affects 0.1% of pregnant women in Australia and is associated with a 3-fold increased risk of stillbirth, fetal hypoxia and compromise, spontaneous preterm birth, as well as increased frequencies of pre-eclampsia and gestational diabetes. ICP is often familial and overlaps with other cholestatic disorders. Treatment options for ICP are not well established, although there are limited data to support the use of ursodeoxycholic acid (UDCA) to relieve pruritus, the main symptom. Rifampicin, a widely used antibiotic including in pregnant women, is effective in reducing pruritus in non-pregnancy cholestasis and has been used as a supplement to UDCA in severe ICP. Many women with ICP are electively delivered preterm, although there are no randomised data to support this approach.

METHODS

We have initiated an international multicentre randomised clinical trial to compare the clinical efficacy of rifampicin tablets (300 mg bd) with that of UDCA tablets (up to 2000 mg daily) in reducing pruritus in women with ICP, using visual pruritus scores as a measuring tool.

DISCUSSION

Our study will be the first to examine the outcomes of treatment specifically in the severe early onset form of ICP, comparing "standard" UDCA therapy with rifampicin, and so be able to provide for the first-time high-quality evidence for use of rifampicin in severe ICP. It will also allow an assessment of feasibility of a future trial to test whether elective early delivery in severe ICP is beneficial.

TRIAL IDENTIFIERS

Australian New Zealand Clinical Trials Registration Number (ANZCTR): 12618000332224p (29/08/2018). HREC No: HREC/18/WCHN/36. EudraCT number: 2018-004011-44. IRAS: 272398. NHMRC registration: APP1152418 and APP117853.

Detection of additional abnormalities or co-morbidities in women with suspected intrahepatic cholestasis of pregnancy

Background

Current guidelines recommend viral, autoimmune, coagulation and liver ultrasound testing in intrahepatic cholestasis of pregnancy to exclude alternative diagnoses.

Methods

Electronic health records were searched for investigations and diagnoses in women with raised bile acid concentrations (>10 µmol/L) between January 2016 and December 2017 at two UK maternity units.

Results

Five hundred and thirty-one women had a raised bile acid concentration (median (IQR): 18 (13-32 µmol/L)) at a median gestation of 35.1 (IQR 31.8-37.0) weeks. Out of 531 women, 250 (47.1%) had full virology, autoimmune and ultrasound tests, and 348 (65.5%) had coagulation performed. Positive hepatitis B and C results were previously known. No new Epstein-Barr virus, cytomegalovirus or hepatitis A diagnoses were made. There were 11 positive autoimmune results, but no new diagnoses. No woman had an unexplained prolonged prothrombin time. No ultrasound liver (n = 38) or gallbladder (n = 85) abnormalities were of acute clinical significance.

Conclusion

Intrahepatic cholestasis of pregnancy investigations provided no new diagnoses that influenced clinical management during pregnancy.

Review article: liver disease in adults with variants in the cholestasis-related genes ABCB11, ABCB4 and ATP8B1

BACKGROUND

Children with intrahepatic cholestasis and genetic variants which result in the disruption of the formation and maintenance of bile (ABCB11, ABCB4 and ATP8B1) generally have a rapidly progressive clinical course. Adults with different phenotypes of cholestasis are increasingly being evaluated for variants in these genes associated with childhood diseases.

AIMS

To review the literature with respect to the presence of variants in cholestasis-related genes in adults with various liver phenotypes, and provide clinical implications of the findings.

METHODS

A search of the literature on variants in specific cholestasis-related genes in adults was conducted.

RESULTS

The common variant p.Val444Ala in ABCB11 confers increased risk of drug-induced liver injury and intrahepatic cholestasis of pregnancy (ICP). Individuals with variants in ABCB4 are at risk of ICP and low phospholipid-associated cholelithiasis. Variants in ABCB4, and possibly ABCB11 and ATP8B1, can be identified in up to a third of patients with cryptogenic chronic cholestasis.

CONCLUSIONS

Individuals with variants in ABCB11 rarely develop cholestasis until BSEP function dips below a threshold, which is also affected by other factors (e.g., drugs, hormones). However, variants in ABCB4 and consequent reduction in MDR3 protein, have a more linear dose-response curve. In individuals with an ABCB11 variant, medications known to reduce BSEP activity should be used cautiously; they should be monitored during pregnancy for ICP; and first-degree relatives should be counselled and screened. No proven management strategy exists, although ursodeoxycholic acid may be beneficial. Further work is needed to define the genotype-phenotype correlation and natural history, and to evaluate the penetrance.

Ursodeoxycholic acid in intrahepatic cholestasis of pregnancy: a secondary analysis of the PITCHES trial

OBJECTIVE

To evaluate whether a particular group of women with intrahepatic cholestasis of pregnancy (ICP), based on their presenting characteristics, would benefit from treatment with ursodeoxycholic acid (UDCA).

DESIGN

Secondary analysis of the PITCHES trial (ISRCTN91918806).

SETTING

United Kingdom.

POPULATION OR SAMPLE

527 women with ICP.

METHODS

Subgroup analyses were performed to determine whether baseline bile acid concentrations or baseline itch scores moderated a woman's response to treatment with UDCA.

MAIN OUTCOME MEASURES

Bile acid concentration and itch score.

RESULTS

In women with baseline bile acid concentrations less than 40 μmol/l, treatment with UDCA resulted in increased post-randomisation bile acid concentrations (geometric mean ratio 1.19, 95% CI 1.00-1.41, P = 0.048). A test of interaction showed no significance (P = 0.647). A small, clinically insignificant difference was seen in itch response in women with a high baseline itch score (-6.0 mm, 95% CI -11.80 to -0.21, P = 0.042), with a test of interaction not showing significance (P = 0.640). Further subgroup analyses showed no significance. Across all women there was a weak relationship between bile acid concentrations and itch severity.

CONCLUSIONS

There was no subgroup of women with ICP in whom a beneficial effect of treatment with UDCA on bile acid concentration or itch score could be identified. This confirms that its routine use in women with this condition for improvement of bile acid concentration or itch score should be reconsidered.

TWEETABLE ABSTRACT

PITCHES: No group of women with ICP has been found in whom UDCA reduces bile acid concentrations or pruritus.

Supplementation with a prebiotic (polydextrose) in obese mouse pregnancy improves maternal glucose homeostasis and protects against offspring obesity

OBJECTIVES

We hypothesised that maternal diet-induced-obesity has adverse consequences for offspring energy expenditure and susceptibility to obesity in adulthood, and that the prebiotic polydextrose (PDX) would prevent the consequences of programming by maternal obesity.

METHODS

Female mice were fed a control (Con) or obesogenic diet (Ob) for 6 weeks prior to mating and throughout pregnancy and lactation. Half the obese dams were supplemented with 5% PDX (ObPDX) in drinking water throughout pregnancy and lactation. Offspring were weaned onto standard chow. At 3 and 6 months, offspring energy intake (EI) and energy expenditure (EE by indirect calorimetry) were measured, and a glucose-tolerance test performed. Offspring of control (OffCon), obese (OffOb) and PDX supplemented (OffObP) dams were subsequently challenged for 3 weeks with Ob, and energy balanced reassessed. Potential modifiers of offspring energy balance including gut microbiota and biomarkers of mitochondrial activity were also evaluated.

RESULTS

Six-month-old male OffOb demonstrated increased bodyweight (BW, P < 0.001) and white adipose tissue mass (P < 0.05), decreased brown adipose tissue mass (BAT, P < 0.01), lower night-time EE (P < 0.001) versus OffCon, which were prevented in OffObP. Both male and female OffOb showed abnormal glucose-tolerance test (peak [Glucose] P < 0.001; AUC, P < 0.05) which was prevented by PDX. The Ob challenge resulted in greater BW gain in both male and female OffOb versus OffCon (P < 0.05), also associated with increased EI (P < 0.05) and reduced EE in females (P < 0.01). OffObP were protected from accelerated BW gain on the OB diet compared with controls, associated with increased night-time EE in both male (P < 0.05) and female OffObP (P < 0.001). PDX also prevented an increase in skeletal muscle mtDNA copy number in OffOb versus OffCon (P < 0.01) and increased the percentage of Bacteroides cells in faecal samples from male OffObP relative to controls.

CONCLUSIONS

Maternal obesity adversely influences adult offspring energy balance and propensity for obesity, which is ameliorated by maternal PDX treatment with associated changes in gut microbiota composition and skeletal muscle mitochondrial function.

Prolonged ursodeoxycholic acid administration reduces acute ischaemia-induced arrhythmias in adult rat hearts

Acute myocardial ischaemia and reperfusion (I-R) are major causes of ventricular arrhythmias in patients with a history of coronary artery disease. Ursodeoxycholic acid (UDCA) has previously been shown to be antiarrhythmic in fetal hearts. This study was performed to investigate if UDCA protects against ischaemia-induced and reperfusion-induced arrhythmias in the adult myocardium, and compares the effect of acute (perfusion only) versus prolonged (2 weeks pre-treatment plus perfusion) UDCA administration. Langendorff-perfused adult Sprague-Dawley rat hearts were subjected to acute regional ischaemia by ligation of the left anterior descending artery (10 min), followed by reperfusion (2 min), and arrhythmia incidence quantified. Prolonged UDCA administration reduced the incidence of acute ischaemia-induced arrhythmias (p = 0.028), with a reduction in number of ventricular ectopic beats during the ischaemic phase compared with acute treatment (10 ± 3 vs 58 ± 15, p = 0.036). No antiarrhythmic effect was observed in the acute UDCA administration group. Neither acute nor prolonged UDCA treatment altered the incidence of reperfusion arrhythmias. The antiarrhythmic effect of UDCA may be partially mediated by an increase in cardiac wavelength, due to the attenuation of conduction velocity slowing (p = 0.03), and the preservation of Connexin43 phosphorylation during acute ischaemia (p = 0.0027). The potential antiarrhythmic effects of prolonged UDCA administration merit further investigation.

Obeticholic acid improves fetal bile acid profile in a mouse model of gestational hypercholanemia

Intrahepatic cholestasis of pregnancy (ICP) is characterized by elevated maternal circulating bile acid levels and associated dyslipidemia. ICP leads to accumulation of bile acids in the fetal compartment, and the elevated bile acid concentrations are associated with an increased risk of adverse fetal outcomes. The farnesoid X receptor agonist obeticholic acid (OCA) is efficient in the treatment of cholestatic conditions such as primary biliary cholangitis. We hypothesized that OCA administration during hypercholanemic pregnancy will improve maternal and fetal bile acid and lipid profiles. Female C57BL/6J mice were fed either a normal chow diet, a 0.5% cholic acid (CA)-supplemented diet, a 0.03% OCA-supplemented diet, or a 0.5% CA + 0.03% OCA-supplemented diet for 1 wk before mating and throughout pregnancy until euthanization on day 18. The effects of CA and OCA feeding on maternal and fetal morphometry, bile acid and lipid levels, and cecal microbiota were investigated. OCA administration during gestation did not alter the maternal or fetal body weight or organ morphometry. OCA treatment during hypercholanemic pregnancy reduced bile acid levels in the fetal compartment. However, fetal dyslipidemia was not reversed, and OCA did not impact maternal bile acid levels or dyslipidemia. In conclusion, OCA administration during gestation had no apparent detrimental impact on maternal or fetal morphometry and improved fetal hypercholanemia. Because high serum bile acid concentrations in ICP are associated with increased rates of adverse fetal outcomes, further investigations into the potential use of OCA during cholestatic gestation are warranted.NEW & NOTEWORTHY We used a mouse model of gestational hypercholanemia to investigate the use of obeticholic acid (OCA), a potent FXR agonist, as a treatment for the hypercholanemia of intrahepatic cholestasis of pregnancy (ICP). The results demonstrate that OCA can improve the fetal bile acid profile. This is relevant not only to women with ICP but also for women who become pregnant while receiving OCA treatment for other conditions such as primary biliary cholangitis and nonalcoholic steatohepatitis.

Maternal glucose homeostasis is impaired in mouse models of gestational cholestasis

Women with intrahepatic cholestasis of pregnancy (ICP), a disorder characterised by raised serum bile acids, are at increased risk of developing gestational diabetes mellitus and have impaired glucose tolerance whilst cholestatic. FXR and TGR5 are modulators of glucose metabolism, and FXR activity is reduced in normal pregnancy, and further in ICP. We aimed to investigate the role of raised serum bile acids, FXR and TGR5 in gestational glucose metabolism using mouse models. Cholic acid feeding resulted in reduced pancreatic β-cell proliferation and increased apoptosis in pregnancy, without altering insulin sensitivity, suggesting that raised bile acids affect β-cell mass but are insufficient to impair glucose tolerance. Conversely, pregnant Fxr-/- and Tgr5-/- mice are glucose intolerant and have reduced insulin secretion in response to glucose challenge, and Fxr-/- mice are also insulin resistant. Furthermore, fecal bile acids are reduced in pregnant Fxr-/- mice. Lithocholic acid and deoxycholic acid, the principal ligands for TGR5, are decreased in particular. Therefore, we propose that raised serum bile acids and reduced FXR and TGR5 activity contribute to the altered glucose metabolism observed in ICP.