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.

Search for an Excess of Electron Neutrino Interactions in MicroBooNE Using Multiple Final-State Topologies

We present a measurement of ν_{e} interactions from the Fermilab Booster Neutrino Beam using the MicroBooNE liquid argon time projection chamber to address the nature of the excess of low energy interactions observed by the MiniBooNE Collaboration. Three independent ν_{e} searches are performed across multiple single electron final states, including an exclusive search for two-body scattering events with a single proton, a semi-inclusive search for pionless events, and a fully inclusive search for events containing all hadronic final states. With differing signal topologies, statistics, backgrounds, reconstruction algorithms, and analysis approaches, the results are found to be either consistent with or modestly lower than the nominal ν_{e} rate expectations from the Booster Neutrino Beam and no excess of ν_{e} events is observed.

1069 ESSENTIAL FRAILTY TOOLSET AS A PREDICTOR OF PROLONGED LENGTH OF STAY AND DISCHARGE DESTINATION AFTER TRANSCATHETER AORTIC VALVE IMPLANTATION

Introduction

Frailty is associated with poor outcomes following transcatheter aortic valve implantation (TAVI). Rockwood is the widely used score for this population. In a recent trial, a more objective score, the Essential Frailty Toolset (EFT) outperformed Rockwood’s in predicting mortality and disability 1-year post-TAVI. Whether it predicts in-hospital length of stay (LOS) and discharge destination post-TAVI remains unclear.

Method

A cohort of patients undergoing TAVI for aortic stenosis was recruited, demographic characteristics collected, and frailty assessed with EFT and Rockwood scores. Primary outcomes were LOS post-TAVI, categorised as ‘not prolonged’ (≤2 days) or ‘prolonged’ (>2 days) and discharge destination, characterised as ‘home’ or ‘non-home’.

Results

86 patients were recruited, with median age 82 years (IQR 78–86). 54% were male. EFT identified 35% and Rockwood 11% as frail. 19% were cognitively impaired. 5 chair rises were completed by 70%, with 30% managing under 15 seconds. Median haemoglobin was 121 g/L (IQR 109.5–136). Median albumin was 36 g/L (IQR 33–39). 84% of procedures were transfemoral. 20% had moderate–severe left ventricular systolic dysfunction. Median LOS post-TAVI was 2 days (IQR 2–5). 94% were discharged home, 6% to referring local hospital or rehabilitation centre. 46% were NYHA class III-IV. A model for prolonged LOS including comorbidities, showed frailty determined by EFT (OR 4.80, CI 95% 1.52–15.2, p = 0.008) but not Rockwood (OR 5.00, CI 95% 0.865–29.0, p = 0.072) was the only significant independent predictor for prolonged LOS. A model adjusting for comorbidities also showed EFT to be an independent predictor for non-home discharge destination of borderline significance (OR 2.57 CI 95% 0.994–6.66, p = 0.051) but Rockwood was not (OR 1.38 CI95% 0.485–3.91, p = 0.548).

Conclusion

In a real-world elderly population, EFT score was a stronger, more independent predictor of prolonged LOS and non-home discharge post-TAVI, than Rockwood’s. EFT would be an effective pre-operative assessment tool for LOS and discharge destination for TAVI.

Expression of MMP2, MMP9 and PGP 9.5 in human aorta in patients with coronary artery disease

Funding Acknowledgements

Type of funding sources: None.

Atherosclerosis has been recognised as inflammatory conditions which involves activation of MMPs of which increased MMP2 & MMP9 expression has been correlated with the development of human aortic plaques.The Sympathetic Nervous System exerts complex control over inflammation in atherosclerosis both: on systemic scale and at the regional level.Protein gene product9.5 (PGP9.5) is a cytoplasmic neuron & is a reliable marker for visualisation of the cardiovascular system innervation.There have been no studies in the existing literature on the expression of PGP 9.5 and MMP2, MMP9 on human aorta.Aim:To study the expression of MMP2, MMP9 and PGP9.5 in the human aorta & gain insights into atherosclerosis & neural modulation in the aorta.Materials &

Methods

This is a single centre, prospective cohort, pilot study with a sample size of 87 patients,done over 2 years at AIMS,Kochi.During CABG, punch biopsy of the aorta taken & processed.One paraffin embedded section used for routine H&E staining & others used for IHC.IHC detection kits use 3, 3’-DABChromogen as a substrate of HRP for visualisation of antigenic structures in the tissues.Positive & negative control tissue were run for all 3 Antibodies.Interpretation done as Diffuse/Focal & Intense/Moderate/ Weak classification based on intensity signals observed on IHC by an experienced Cardiac Pathologist.Results:7 Controls with well matched baseline characteristics: Controls-Aorta samples taken from patients who were undergoing Aortic Valve Surgery for Aortic Valve disease with normal coronaries documented on a coronary angiogram.65.9% of patients with Positive MMP2 & 28.6 % of patients in the Control group was found to have significant difference when compared to positive & negative outcomes amongst the 2 groups.89.3% of patients with positive MMP2 had significant co-relation with PGP9.5 levels expressed in the same specimen analysed.MMP9 also had a p value of 0.002 suggesting a significant co-relation between MMP9 & PGP9.5.Statistically significant Co-relation seen between the Age, CRP & the levels of MMP 9 expressed in the Aorta observed.MMP2 & MMP9 expression have a definite & significant co-expression with PGP9.5 expression in human aorta,suggesting a novel marker of neuromodulation in atherosclerotic process in human aorta.

Expression of MMP2, MMP9 and PGP 9.5 in human aorta in patients with coronary artery disease

POS1234 DMARD DISRUPTION, INCREASED DISEASE ACTIVITY, AND PROLONGED SYMPTOM DURATION AFTER ACUTE COVID-19 AMONG PATIENTS WITH RHEUMATIC DISEASE: A PROSPECTIVE STUDY

Background

Systemic autoimmune rheumatic disease (SARD) patients may be at risk for disease flare and prolonged symptom duration after COVID-19, perhaps related to DMARD disruption and immune activation.

Objectives

To describe DMARD disruption and identify differences in SARD activity among patients with and without prolonged COVID-19 symptom duration.

Methods

We identified all SARD patients with confirmed COVID-19 at the Mass General Brigham healthcare system in Boston, USA; prospective recruitment is ongoing. Surveys were used to collect demographics, clinical characteristics, DMARD disruption, COVID-19 course, and SARD disease activity before and after COVID-19. The survey included validated instruments measuring disease activity, pain, fatigue, functional status, and respiratory quality of life. Prolonged symptom duration was defined as COVID-19 symptoms lasting ≥28 days. We compared differences in patient-reported measures between those with and without prolonged symptoms.

Results

We analyzed survey responses from 174 COVID-19 survivors with SARDs (mean age 52±16 years, 81% female, 80% White). The most common SARDs were RA (40%) and SLE (14%). Fifty-one percent of the 127 respondents on any DMARD reported a disruption to their regimen at COVID-19 onset (Figure 1). Among individual DMARDs, 56-77% were reported to have any change, except for hydroxychloroquine (23%) and rituximab (46%). SARD flare after COVID-19 was reported by 41% of respondents (Table 1). Patient global assessment of SARD activity was worse after COVID-19 (mean 7.6±2.3 before vs. 6.6±2.9 after COVID-19, p<0.001). Prolonged symptom duration was reported by 45% of participants. Those with prolonged symptoms had a higher initial COVID-19 symptom count (median 7 vs. 4, p<0.001) and were more likely to be hospitalized for COVID-19 (28% vs. 17%, p=0.001). Respondents experiencing prolonged symptom duration had higher disease activity on RAPID3 (p=0.007) as well as more pain (p<0.001) and fatigue (p=0.03) compared to those without prolonged symptoms.

Table 1.

Acute COVID-19 course, SARD flare/activity, and patient-reported outcomes among COVID-19 survivors with SARDs.

All COVID-19 survivors with SARDs (n=174)Prolonged symptom duration ≥28 days (n=78)No prolonged symptom duration/(n=96)p-value (prolonged vs. not)Acute COVID-19 courseCOVID-19 symptom duration, days, median [IQR]14 [9, 29]46 [30, 65]11 [7, 14]<0.0001Initial symptom count, median [IQR]6 [3, 8]7 [6, 9]4 [2, 7]<0.001Hospitalized, n (%)38 (22)22 (28)16 (17)0.001SARD flare/activitySelf-reported SARD flare after COVID-19, n (%)71 (41)38 (49)33 (34)0.15Disease activity by RAPID3, median [IQR]9 [4, 14]11.2 [6, 16]7 [3, 13]0.0067RAPID3 categorical score, n (%)0.13Remission (0)11 (7)4 (5)7 (7)Near remission (0.3-1.0)23 (14)5 (7)18 (19)Low severity (1.3-2.0)26 (15)10 (14)16 (17)Moderate severity (2.3-4.0)55 (33)27 (36)28 (29)High severity (4.3-10.0)54 (32)28 (38)26 (27)Patient-reported outcomesPain by SF-MPQ, median [IQR]2 [1, 2]2 [1, 2]1 [0, 2]0.0008Fatigue by FSI, median [IQR]53 [27, 84]66 [31, 91.5]43 [26, 76]0.031mHAQ, median [IQR]0.125 [0, 0.38]0.25 [0, 0.75]0.125 [0, 0.38]0.11Respiratory quality of life by SGRQ, global [IQR]15 [4, 29]16 [4, 36]10 [4, 26]0.49

RAPID3, Routine Assessment of Patient Index Data 3; SF-MPQ, Short-form McGill Pain Questionnaire; FSI, Fatigue Symptom Inventory; mHAQ, modified Health Assessment Questionnaire; SGRQ, Saint George’s Respiratory Questionnaire.

Figure 1.

Frequency of baseline DMARD use and proportion with any disruption at COVID-19 onset.

Conclusion

DMARD disruption, SARD flare, and prolonged symptoms were common in this prospective study of COVID-19 survivors with SARDs. Those with prolonged COVID-19 symptom duration, defined as ≥28 days, had higher SARD activity, more pain, and more fatigue compared to those without prolonged symptoms. These findings suggest that post-acute sequelae of COVID-19 may have a large impact on underlying SARD activity and quality of life.

Disclosure of Interests

Michael Di Iorio: None declared, Claire Cook: None declared, Kathleen Vanni: None declared, Naomi Patel Consultant of: Receives consulting fees from FVC Health unrelated to this work., Kristin D’Silva: None declared, Xiaoqing Fu: None declared, Jiaqi Wang: None declared, Lauren Prisco: None declared, Emily Kowalski: None declared, Alessandra Zaccardelli: None declared, Lily Martin: None declared, Grace Qian: None declared, Tiffany Hsu: None declared, Zachary Wallace Consultant of: Receives consulting fees from Viela Bio, Zenas BioPharma, and MedPace unrelated to this work., Grant/research support from: Receives research support from Bristol-Myers Squibb and Principia/Sanofi., Jeffrey Sparks Consultant of: Receives consultant fees from AbbVie, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Gilead, Inova Diagnostics, Janssen, Optum, and Pfizer unrelated to this work., Grant/research support from: Receives research support from Bristol Myers Squibb.

POS0833 DIFFERENCES BETWEEN AVACOPAN AND PREDNISONE FOR THE TREATMENT OF ANCA-ASSOCIATED VASCULITIS AT DIFFERENT THRESHOLDS OF GLUCOCORTICOID TOXICITY

Background

Treatment with glucocorticoids (GCs) for ANCA-associated vasculitis (AAV) is associated with substantial toxicity. The Glucocorticoid Toxicity Index (GTI) was developed to measure change in GC toxicity over time.1 Data from the composite GTI domains provide both an Aggregate Improvement Score (AIS) and a Cumulative Worsening Score (CWS) of GC toxicity, permitting the instrument to compare both improvement and worsening of GC toxicity across treatment groups. The GTI was a pre-specified secondary outcome in ADVOCATE, a randomized, double-blind, placebo-controlled trial in patients with AAV that aimed to replace a GC taper with avacopan, a complement C5a receptor inhibitor. Patients were randomized to either avacopan or a prednisone taper on a background of either cyclophosphamide or rituximab.2 In ADVOCATE, the median GC exposure was 400 mg vs. 2939 mg in the avacopan and prednisone groups, respectively, which is an 86% median reduction in GC exposure from all sources. Remission rates were comparable in the two groups at 26 weeks (72.3% vs. 70.1%, respectively), and avacopan was superior at 52 weeks (sustained remission in 65.7% vs. 54.9%).2

Objectives

To compare GC toxicity between the treatment groups at three different thresholds of GC toxicity, beginning with the minimum detectable difference (MDD) of the GTI.

Methods

The MDD for the GTI (10 points) was calculated in the initial validation phase of the instrument. Thus, any GTI score > 10 points may be considered to represent a true change in GC toxicity. We compared the two groups at GTI thresholds of 10, 20, and 30 points for both the CWS and AIS. The CWS comprises a total of all GC-related toxicities that have occurred in the GTI between baseline and 26 weeks (time of primary outcome). The AIS, in contrast, allows toxicities to be added if they are new or subtracted if they improve. Higher CWS and AIS values indicate greater severity of GC toxicity. The two scores together capture the nuances of longitudinal GC toxicity across multiple domains. We compared the percentages of those in the two treatment groups who exceeded GTI threshold values of 10, 20, and 30 points in the CWS or AIS.

Results

The percentages of patients exceeding the specified AIS thresholds differentiated the avacopan group from the prednisone group (48.2% vs. 60.4%, respectively, at the 10-point threshold, p=0.02; 29.5% vs. 45.1% at the 20-point threshold, p=0.003; and 18.1% vs. 33.5% at the 30-point threshold, p=0.001) (Table 1). The CWS differentiated avacopan from prednisone at the 20- and 30-point thresholds (57.8% vs 73.2%, respectively, at 20 points, p=0.002; 41.0% vs 55.5% at 30 points, p=0.007).

Table 1.

Percentages of Patients in ADVOCATE Exceeding Selected GTI Thresholds at Week 26

GTI threshold/study groupn (%) exceeding CWS thresholdp-valuen (%) exceeding AIS thresholdp-valueGTI worsening > 10 points Avacopan (N = 164)138 (83.1%)0.14780 (48.2%)0.022 Prednisone (N = 166)144 (87.8%)99 (60.4%)GTI worsening > 20 points Avacopan (N = 164)96 (57.8%)0.00249 (29.5%)0.003 Prednisone (N = 166)120 (73.2%)74 (45.1%)GTI worsening > 30 points Avacopan (N = 164)68 (41.0%)0.00730 (18.1%)0.001 Prednisone (N = 166)91 (55.5%)55 (33.5%)

AIS, Aggregate Improvement Score; CWS, Cumulative Worsening Score; GTI, Glucocorticoid Toxicity Index

Conclusion

Among patients with AAV, treatment with avacopan was associated with lower GC toxicity across multiple GTI thresholds compared to treatment with prednisone, consistent with the substantial reduction in total GC exposure associated with avacopan. The GTI scores differentiated the two treatment groups effectively through a composite of GC toxicity domains.

References

[1]McDowell PJ, Stone JH, Zhang Y, et al. Quantification of Glucocorticoid-Associated Morbidity in Severe Asthma Using the Glucocorticoid Toxicity Index. J Allergy Clin Immunol Pract. 2021; 9:365-72.

[2]Jayne DRW, Merkel PA, Schall TJ, et al. Avacopan for the Treatment of ANCA-Associated Vasculitis. N Engl J Med. 2021;384:599-609.

Disclosure of Interests

Naomi Patel: None declared, Yuqing Zhang: None declared, David Jayne Speakers bureau: Amgen, Vifor, Consultant of: Astra-Zeneca, BMS, Boehringer-Ingelheim, Chemocentryx, GSK, Novartis, Otsuka, Roche/Genentech, Takeda, UCB & Vifor, Grant/research support from: GSK, Roche/Genentech, Peter A Merkel Consultant of: AbbVie, AstraZeneca, Boeringher-Ingelheim, Bristol-Myers Squibb, ChemoCentryx, Forbius, Genentech/Roche, Genzyme/Sanofi, GlaxoSmithKline, Immagene, InflaRx, Jannsen, Kiniksa, Kyverna, Magenta, MiroBio, Novartis, Pfizer, Regeneron, Sparrow, Takeda, Talaris, Grant/research support from: AbbVie, AstraZeneca, Boeringher-Ingelheim, Bristol-Myers Squibb, ChemoCentryx, Forbius, Genentech/Roche, Genzyme/Sanofi, GlaxoSmithKline, InflaRx, Sanofi, Takeda, Huibin Yue Shareholder of: ChemoCentryx, Employee of: ChemoCentryx, Pirow Bekker Shareholder of: ChemoCentryx, Consultant of: ChemoCentryx, Employee of: ChemoCentryx, John H. Stone Shareholder of: Steritas, Consultant of: ChemoCentryx, Roche/Genentech, Sanofi, Bristol-Myers Squib, AbbVie, InflaRx, Kyverna, Novartis, Q32Bio, Zenas, Horizon, Grant/research support from: Roche/Genentech, Horizon, Sanofi, Bristol-Myers Squib

OP0251 IMPACT OF INTERSTITIAL LUNG DISEASE ON SEVERE COVID-19 OUTCOMES FOR PATIENTS WITH RHEUMATOID ARTHRITIS: A MULTICENTER STUDY

Background

RA has been associated with poor COVID-19 outcomes, but few studies have investigated outcomes in RA features such as interstitial lung disease.

Objectives

To assess COVID-19 outcomes in patients with RA overall, and those with and without ILD, compared to general population comparators.

Methods

A multicenter, retrospective cohort study was conducted at Mayo Clinic (19 hospitals and affiliated outpatient centers in 4 states) and Mass General Brigham (14 hospitals and affiliated outpatient centers in New England). Consecutive patients with RA meeting ACR/EULAR criteria and a positive COVID-19 test from March 1, 2020 through June 6, 2021 were matched 1:5 on age, sex, race, and COVID-19 test date with general population comparators without RA. RA features assessed included: RA-ILD per Bongartz criteria [1], duration, rheumatoid factor (RF), cyclic citrullinated peptide antibody (CCP), bone erosions, and treatments. The primary outcome was a composite of hospitalization or death following COVID-19 diagnosis. We used multivariable Cox regression to investigate the association of RA, and features such as ILD, with COVID-19 outcomes compared to matched comparators.

Results

We analyzed 582 patients with RA and 2892 comparators without RA, all with COVID-19. Mean age was 62 years, 51% were female, and 79% were White. Mean RA duration was 11 years, 67% were seropositive (52% RF+ and 54% CCP+), 27% had bone erosions, 28% were on steroids, and 79% were on DMARDs. 50/582 (9%) patients with RA had ILD.

The COVID-19 hospitalization or death rate for RA patients was higher than comparators (3.0 per 1,000 days [95% CI 2.5-3.6] vs. 1.9 per 1,000 days [95% CI 1.7-2.1], respectively). Overall, RA patients had a 53% higher risk of hospitalization or death than comparators after adjustment (95% CI 1.20-1.94).

Among those with RA-ILD, the hospitalization or death rate was significantly higher than comparators (10.9 [95% CI 6.7-15.2] vs. 2.5 per 1,000 days [1.8-3.2], respectively). RA-ILD was associated with nearly 3-fold higher risk for hospitalization or death than comparators (multivariable HR 2.84 [95% CI 1.64-4.91], Table 1). There was a significant interaction between RA/comparator status and presence/absence of ILD for risk of severe COVID-19 (p<0.001, Figure 1). The elevated risk for severe COVID-19 was similar for RA subgroups defined by serostatus or bone erosions.

Table 1.

Frequencies, proportions, and hazard ratios for COVID-19 outcomes, comparing all RA patients, and subgroups with or without RA-ILD, to matched comparators.

COVID-19 OutcomesAll RA Patients (n=582)RA-ILD (n=50)RA Patients without ILD (n=532)Comparators (n=2,892)Hospitalization, n (%)121 (21)24 (48)97 (18)402 (14)Unadjusted HR (95% CI)1.58 (1.27, 1.96)2.65 (1.71, 4.09)1.43 (1.12, 1.82)Ref.Adjusted* HR (95% CI)1.45 (1.14, 1.83)2.35 (1.38, 4.00)1.31 (1.00, 1.70)Ref.Death, n (%)26 (4)9 (18)17 (3)63 (2)Unadjusted HR (95% CI)1.72 (0.98, 3.01)5.88 (2.07, 16.71)1.13 (0.56, 2.29)Ref.Adjusted* HR (95% CI)1.24 (0.66, 2.32)13.94 (4.30, 45.18)0.75 (0.35, 1.63)Ref.Hospitalization or death, n (%)126 (22)25 (50)101 (19)419 (14)Unadjusted HR (95% CI)1.66 (1.33, 2.07)3.01 (1.93, 4.70)1.47 (1.14, 1.89)Ref.Adjusted* HR (95% CI)1.53 (1.20, 1.94)2.84 (1.64, 4.91)1.34 (1.02, 1.77)Ref.

*Adjusted for age, sex, race, and smoking

Figure 1.

Multivariable hazard ratios for the composite outcome of hospitalization or death from COVID-19, comparing all RA and subgroups by serostatus, bone erosions, and ILD to matched comparators without RA.

Conclusion

We confirmed that RA was associated with severe COVID-19 outcomes compared to the general population. We found evidence that ILD may be an effect modifier for the relationship between RA and severe COVID-19 outcomes, but RA subgroups defined by serostatus and bone erosions had similarly elevated risk. These findings suggest that ILD or its treatment may be a major contributor to severe COVID-19 outcomes in RA.

References

[1]Bongartz, T, et al, Arthritis Rheum. 2010 Jun;62(6):1583-91.

Disclosure of Interests

None declared

Radiogenomic analysis of primary breast cancer reveals [18F]-fluorodeoxglucose dynamic flux-constants are positively associated with immune pathways and outperform static uptake measures in associating with glucose metabolism

BACKGROUND

PET imaging of 18F-fluorodeoxygucose (FDG) is used widely for tumour staging and assessment of treatment response, but the biology associated with FDG uptake is still not fully elucidated. We therefore carried out gene set enrichment analyses (GSEA) of RNA sequencing data to find KEGG pathways associated with FDG uptake in primary breast cancers.

METHODS

Pre-treatment data were analysed from a window-of-opportunity study in which 30 patients underwent static and dynamic FDG-PET and tumour biopsy. Kinetic models were fitted to dynamic images, and GSEA was performed for enrichment scores reflecting Pearson and Spearman coefficients of correlations between gene expression and imaging.

RESULTS

A total of 38 pathways were associated with kinetic model flux-constants or static measures of FDG uptake, all positively. The associated pathways included glycolysis/gluconeogenesis ('GLYC-GLUC') which mediates FDG uptake and was associated with model flux-constants but not with static uptake measures, and 28 pathways related to immune-response or inflammation. More pathways, 32, were associated with the flux-constant K of the simple Patlak model than with any other imaging index. Numbers of pathways categorised as being associated with individual micro-parameters of the kinetic models were substantially fewer than numbers associated with flux-constants, and lay around levels expected by chance.

CONCLUSIONS

In pre-treatment images GLYC-GLUC was associated with FDG kinetic flux-constants including Patlak K, but not with static uptake measures. Immune-related pathways were associated with flux-constants and static uptake. Patlak K was associated with more pathways than were the flux-constants of more complex kinetic models. On the basis of these results Patlak analysis of dynamic FDG-PET scans is advantageous, compared to other kinetic analyses or static imaging, in studies seeking to infer tumour-to-tumour differences in biology from differences in imaging. Trial registration NCT01266486, December 24th 2010.

First Measurement of Energy-Dependent Inclusive Muon Neutrino Charged-Current Cross Sections on Argon with the MicroBooNE Detector

We report a measurement of the energy-dependent total charged-current cross section σ(E_{ν}) for inclusive muon neutrinos scattering on argon, as well as measurements of flux-averaged differential cross sections as a function of muon energy and hadronic energy transfer (ν). Data corresponding to 5.3×10^{19} protons on target of exposure were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab booster neutrino beam with a mean neutrino energy of approximately 0.8 GeV. The mapping between the true neutrino energy E_{ν} and reconstructed neutrino energy E_{ν}^{rec} and between the energy transfer ν and reconstructed hadronic energy E_{had}^{rec} are validated by comparing the data and Monte Carlo (MC) predictions. In particular, the modeling of the missing hadronic energy and its associated uncertainties are verified by a new method that compares the E_{had}^{rec} distributions between data and a MC prediction after constraining the reconstructed muon kinematic distributions, energy, and polar angle to those of data. The success of this validation gives confidence that the missing energy in the MicroBooNE detector is well modeled and underpins first-time measurements of both the total cross section σ(E_{ν}) and the differential cross section dσ/dν on argon.

Search for Neutrino-Induced Neutral-Current Δ Radiative Decay in MicroBooNE and a First Test of the MiniBooNE Low Energy Excess under a Single-Photon Hypothesis

We report results from a search for neutrino-induced neutral current (NC) resonant Δ(1232) baryon production followed by Δ radiative decay, with a ⟨0.8⟩  GeV neutrino beam. Data corresponding to MicroBooNE's first three years of operations (6.80×10^{20} protons on target) are used to select single-photon events with one or zero protons and without charged leptons in the final state (1γ1p and 1γ0p, respectively). The background is constrained via an in situ high-purity measurement of NC π^{0} events, made possible via dedicated 2γ1p and 2γ0p selections. A total of 16 and 153 events are observed for the 1γ1p and 1γ0p selections, respectively, compared to a constrained background prediction of 20.5±3.65(syst) and 145.1±13.8(syst) events. The data lead to a bound on an anomalous enhancement of the normalization of NC Δ radiative decay of less than 2.3 times the predicted nominal rate for this process at the 90% confidence level (C.L.). The measurement disfavors a candidate photon interpretation of the MiniBooNE low-energy excess as a factor of 3.18 times the nominal NC Δ radiative decay rate at the 94.8% C.L., in favor of the nominal prediction, and represents a greater than 50-fold improvement over the world's best limit on single-photon production in NC interactions in the sub-GeV neutrino energy range.

A tetranuclear nickel(II) complex, [Ni4(L)4](ClO4)4·C2H3N·2H2O, with an asymmetric Ni4O4 open-cubane-like core

A tetra­nuclear complex with an open-cubane like structure was synthesized from 2-meth­oxy-6-(pyridin-2-yl-hydrazonometh­yl)-phenol and characterized using micro-analytical and spectroscopic techniques, and single-crystal X-ray diffraction analysis.

A tetra­nuclear complex with an open-cubane-like core structure was synthesized from 2-meth­oxy-6-(pyridin-2-yl-hydrazonometh­yl)phenol (HL), namely, cyclo-tetra­kis­(μ-2-meth­oxy-6-{[2-(pyridin-2-yl)hydrazin-1-yl­idene]meth­yl}pheno­lato)tetra­nickel(II) tetra­kis­(perchlorate) aceto­nitrile monosolvate dihydrate, [Ni₄(C₁₃H₁₂N₃O₂)₄](ClO₄)₄·C₂H₃N·2H₂O, and characterized using micro-analytical and spectroscopic techniques. The crystal-structure determination reveals the formation of a distorted Ni₄O₄ cubane-like core architecture encapsulated by four hydrazone Schiff base (HL) mol­ecules. A open-cube tetra­nuclear architecture is created in which nickel(II) ions of the NiN₂O₃ unit are connected by μ₂-O anions of the phenolate moiety of HL. In this complex, each Ni centre has a slightly distorted square-pyramidal coordination environment. The supra­molecular architectures are stabilized via the presence of various inter­molecular hydrogen bonds and (ar­yl–aryl, ar­yl–chelate and chelate–chelate) stacking inter­actions.

Role of Uterine Artery Doppler at 11-14 Weeks of Pregnancy in Early Prediction of Preeclampsia: A Prospective Cohort Study

Introduction: Doppler ultrasonography, by comparing systolic and diastolic waveforms helps in assessment of uteroplacental circulation. Since preeclampsia has ethnic and geographical variations, it is important to understand the prediction modalities in various populations. Aim: To investigate the role of elevated Pulsatility Index (PI) and presence of diastolic notch using uterine artery doppler in early pregnancy in predicting development of preeclampsia among pregnant women. Materials and Methods: A prospective cohort study was conducted on pregnant females visiting the antenatal clinic or Outpatient Department or admitted in the Department of Obstetrics and Gynaecology at People's College of Medical Sciences and Research Centre, Bhopal, Madhya Pradesh, India, from November 2019 to October 2021. All cases were subjected to uterine artery doppler study, between 11-14 weeks of pregnancy, to note pulsatility index and diastolic notch. All the participants were then screened periodically during their antenatal visits for development of features of preeclampsia and were followed-up monthly upto 20 weeks, every 15 days upto 32 weeks and then weekly till delivery. Pregnancy outcome were measured in terms of presence or absence of preeclampsia. Data was compiled using Microsoft Excel and analysed using Statistical Package for Social Sciences (SPSS) IBM software version 20.0. Categorical data was expressed as frequency and proportions whereas continuous data was expressed as mean and standard deviation. Results: The present study was conducted on a total of 116 cases with the mean age of 26.75±4.31 years. Out of 116 cases, 26 cases developed preeclampsia. Diastolic notch was present in 17 cases (65.4%) patients with preeclampsia and 23 cases (25.6%) non preeclampsia patients. Pulsatility index of more than 1.71 was noted in 14 cases (53.8%) cases with preeclampsia where as 87 cases (96.7%) with non preeclampsia had pulsatility index of less than 1.71. The specificity of diastolic notch 74.4% where as that of pulsatility Index was 96.7 % and the diagnostic accuracy of diastolic notch 72.4% where as that of pulsatility index was 87.1%. Conclusion: Uterine artery doppler is a promising tool for predicting development of preeclampsia by analysing both PI as well as diastolic notch in uterine artery. Doppler had high overall diagnostic accuracy for preeclampsia.

Prevalence of Anaemia in Women with Unsupervised Medical AbortionAn Observational Study

Introduction: According to American College of Obstetricians and Gynecologists (ACOG) and other organisations such as the Society of Family Planning (SFP) and American Society for Reproductive Medicine (ASRM), abortion services are considered as an essential component of comprehensive healthcare. Such services are considered as a time-sensitive issue, as delay in getting comprehensive abortion services may be associated with significant impact on physical health, wellbeing and mental health of the individual. Aim: To determine proportion of women presenting to Gynaecologyy Outpatient Department (OPD) with unsupervised use of abortion pills and to estimate the percentage of anaemia among these women. Materials and Methods: The present observational study was conducted on 148 women attending the Gynaecology OPD in People’s Hospital and seeking treatment for complications due to unsupervised use of abortion pills during the study period of 18 months. A thorough history was obtained and a thorough physical examination was conducted. Haemoglobin estimation and Ultrasonography (USG) was done to determine complications. Data was compiled using MS Excel and results were expressed in terms of frequency and percentages and mean±SD. Results: During the study period, a total of 360 cases with abortions were registered, of them 150 cases were unsupervised attributing to 41.7% cases. Out of 150 females with unsupervised abortions, 2 females did not give consent to participate and thus a total of 148 females were enrolled. Consumption of unsupervised abortion pills resulted in incomplete abortion in 77 (52%) cases, while complete abortion was reported in only 22 (14.9%) cases. Other complications observed in a few cases were septic shock, in 7 (4.7%) haemorrhagic shock in 4 (2.7%), secondary infertility in 3 (2%), inevitable abortion in 3 (2%), ruptured ectopic pregnancy in 3 (2%) and chronic ovarian ectopic in 1 (0.7%). Missed abortion was documented in 20 (13.5%) cases after complete examination and in 8 (5.4%) cases viable intrauterine pregnancy was diagnosed. Mild, moderate and severe anaemia was observed in 19 (12.8%), 98 (66.2%) and 12 (8.1%) females respectively. Conclusion: The unsupervised use of abortion pills not only increases maternal morbidity but also has been associated with life threatening complications such as septic shock, haemorrhagic shock, ruptured ectopic pregnancy etc. Anaemia is one of the most common complication of unsupervised pill consumption and preventing the latter may obviate the need for blood transfusion.

Development, evaluation and validation of machine learning algorithms to detect atypical and asymptomatic presentations of Covid-19 in hospital practice

BACKGROUND

Diagnostic methods for Covid-19 have improved, both in speed and availability. Because of atypical and asymptomatic carriage of the virus and nosocomial spread within institutions, timely diagnosis remains a challenge. Machine learning models trained on blood test results have shown promise in identifying cases of Covid-19.

AIMS

To train and validate a machine learning model capable of differentiating Covid-19 positive from negative patients using routine blood tests and assess the model's accuracy against atypical and asymptomatic presentations.

DESIGN AND METHODS

We conducted a retrospective analysis of medical admissions to our institution during March and April 2020. Participants were categorized into Covid-19 positive or negative groups based on clinical, radiological features or nasopharyngeal swab. A machine learning model was trained on laboratory parameters and validated for accuracy, sensitivity and specificity and externally validated at an unconnected establishment.

RESULTS

An Ensemble Bagged Tree model was trained on data collected from 405 patients (212 Covid-19 positive) producing an accuracy of 81.79% (95% confidence interval (CI) 77.53-85.55%), the sensitivity of 85.85% (CI 80.42-90.24%) and specificity of 76.65% (CI 69.49-82.84%). Accuracy was preserved for atypical and asymptomatic subgroups. Using an external data set for 226 patients (141 Covid-19 positive) accuracy of 76.82% (CI 70.87-82.08%), sensitivity of 78.38% (CI 70.87-84.72%) and specificity of 74.12% (CI 63.48-83.01%) was achieved.

CONCLUSION

A machine learning model using routine laboratory parameters can detect atypical and asymptomatic presentations of Covid-19 and might be an adjunct to existing screening measures.

Heavy Metal Contamination in Soils and Crops Irrigated by Kali River in Uttar Pradesh, India

The study investigated concentrations, distribution, and bioaccumulation of heavy metals in agriculture soil and crops irrigated by the Kali River of Uttar Pradesh, India. Soils and crop samples were collected from 17 locations along the river and analyzed for heavy metal concentrations. Metals in soil and plant were recorded as Fe > Zn > Mn > Cu > Ni > Pb > Cr > Cd and Mn > Fe > Zn > Cu > Cr > Ni > Pb > Cd, respectively. The bioaccumulation factor was < 1 that indicates lesser accumulation of metals in plants except for Cd, Mn, and Zn. Metal pollution index ranged between 1.84 and 6.62 and shows that crops growing at the S₁₀ to S₁₇ sites accumulate greater metal concentrations. Cluster analysis showed agglomeration of Cr-Pb-Cd, Cu-Ni-Mn, and Fe-Zn which revealed different sources of metal pollution. The present study shows low to moderate heavy metal pollution in Kali River irrigated areas thus consumption of agriculture produce may cause adverse health effects.

Effect of thrombocytopenia in patients with infective endocarditis: an insight from the National Inpatient Sample database

Introduction

Infective endocarditis (IE) is one of the feared diseases in septic patients, and incidences are rising due to the intravenous drug abuse epidemic. Sepsis causes an escalation of the platelet destructions leading to thrombocytopenia (1). Few independent hospital-based studies have proposed increase mortality with thrombocytopenia in patients with IE (2–5). We aim to evaluate the significance of thrombocytopenia in IE subjects from the national inpatient sample (NIS) database.

Method

We analyzed the NIS database from Jan-2016 to Dec-2018 using Stata 16.0. NIS is the largest publicly available all-payer inpatient care database in the United States, containing data on more than seven million hospital stays per year. We identified patients with IE with or without thrombocytopenia using ICD-10 codes. The primary outcome of interest was in-hospital mortality comparison. We adjusted potential confounders (age, sex, diabetes, hypertension, etc.) with multivariate logistic regression analysis. Further analysis was done after balancing the population co-morbidity using a Greedy propensity match for accuracy.

Results

A total of 174,495 subjects were included in this study with a diagnosis of IE. Among these individuals, 33,285 patients had a concurrent diagnosis of thrombocytopenia. The mean ages were 53±19.5 years for the thrombocytopenia group and 55±19.8 years for others. Females were equally represented in both cohorts. There were 4,945 (14.86%) vs 2,835 (2.01%) mortalities reported in with and without thrombocytopenia group respectively. After propensity matching, there was a pronounced increase in mortality [Odds ratio (OR): 1.93 (1.72 – 2.15), p-value: &lt;0.001] in the group with thrombocytopenia comparing to others. Complications such as Major bleeding requiring blood transfusion [OR: 1.45 (1.35–1.57)], acute myocardial infarction [OR: 1.56 (1.35–1.70)], complete heart block [OR: 1.44 (1.16–1.53)], cardiac arrest [OR: 1.44 (1.25–1.72)], acute respiratory failure [OR: 1.51 (1.39–1.73)] and pressor support requirement [(OR: 1.73 (1.57–2.01)] were notably higher in the cohort of thrombocytopenia with statistically significant p-value (&lt;0.001). The difference in length of stay between both cohorts after propensity match wasn't statistically significant.

Conclusion

In conclusion, IE patients with thrombocytopenia have higher incidences of in-patient mortality and poor outcomes than cohort without thrombocytopenia. Some of the adverse consequences could be temporally explained by complications related to underlying thrombocytopenia. Further investigations are needed to delineate the outcome in this group of subjects.

Funding Acknowledgement

Type of funding sources: None.

Impact of atrial fibrillation in patients with colorectal cancer: a national inpatient sample database analysis

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting approximately 1–2% overall population (1). Its causal relationship with colorectal cancer (CRC) is much for debate. According to one hypothesis, the presence of autoantibodies directed against ionic channels or acetylcholine receptors can predispose to the development of atrial fibrillation (2–3). Thus, AF may be regarded as an inflammatory complication in patients with colon cancer. Our study objective was to determine if AF impacts the outcome of patients with CRC.

Method

We analyzed the National Inpatient Sample (NIS) database from Oct-2015 to Dec 2018 using Stata 16.0. The NIS databases are released under the Healthcare Cost and Utilization Project, which includes inpatient admissions from the United States' participating hospitals. Total population with CRC were identified using their respective ICD-10 diagnostic codes then divided based on AF. To determine atrial fibrillation association with mortality and complications, we used multivariate logistic regression analysis using weights to generate nationally representative results. Later, a propensity-matched population analysis was done for the accuracy of the results.

Result

We found 245,305 patients admitted with CRC between Oct 2015 to Dec-2018 in the USA, out of which 28,170 (11.5%) were having AF. The mean age for the patients with AF was 77±10 compare to 65±14 years in those without AF. Patients with AF were associated with higher comorbidities and had a high population percentage with Carlson category three or above. There were 1,456 (5.2%) mortalities in the AF group compared to 5,689 (2.6%) in the other. The higher odds of mortality in patients with AF was present in multivariate logistic regression analysis in both non-propensity matched [1.71 (1.45–2.02), P-value: &lt;0.000] and propensity-matched [1.44 (1.18–1.75), P-value: &lt;0.001] cohorts. Patients with AF were hospitalized longer (9.20±7.8 vs. 6.85±7.0 days), leading to a high admission costs (US$ 25,875±22,875 vs. 20,087±19,314). Odds of complications such as need for blood transfusions [1.61 (1.05–1.29), P-value: 0.005], hemorrhage requiring blood transfusion [1.17 (1.05–1.29), P-value: 0.003], lower-GI bleed [1.31 (1.21–1.43), P-value: &lt;0.001], sepsis [1.45 (1.30–1.62), P-value: &lt;0.001], respiratory failure [1.39 (1.15–1.67), P-value: 0.001] etc. were also higher in group of patients with CRC and AF.

Conclusion

In our retrospective, propensity-matched national inpatient sample analyses of patients admitted with colorectal cancer, atrial fibrillation is associated with higher morbidity and mortality. AF was associated with a high burden of complications with prolonged hospital stay leading to increased health care expenditures.

Funding Acknowledgement

Type of funding sources: None.