Real-world diagnostic outcomes and cost-effectiveness of genome-wide sequencing for developmental and seizure disorders: Evidence from Canada

PURPOSE

To determine real-world diagnostic rates, cost trajectories, and cost-effectiveness of exome sequencing (ES) and genome sequencing (GS) for children with developmental and/or seizure disorders in British Columbia, Canada.

METHODS

Based on medical records review, we estimated real-world costs and outcomes for 491 patients who underwent standard of care (SOC) diagnostic testing at British Columbia Children's Hospital. Results informed a state-transition Markov model examining cost-effectiveness of 3 competing diagnostic strategies: (1) SOC with last-tier access to ES, (2) streamlined ES access, and (3) first-tier GS.

RESULTS

Through SOC, 49.4% (95% CI: 40.6, 58.2) of patients were diagnosed at an average cost of C$11,683 per patient (95% CI: 9200, 14,166). Compared with SOC, earlier ES or GS access yielded similar or improved diagnostic rates and shorter times to genetic diagnosis, with 94% of simulations demonstrating cost savings for streamlined ES and 60% for first-tier GS. Net benefit from the perspective of the health care system was C$2956 (95% CI: -608, 6519) for streamlined ES compared with SOC.

CONCLUSION

Using real-world data, we found earlier access to ES may yield more rapid genetic diagnosis of childhood developmental and seizure disorders and cost savings compared with current practice in a Canadian health care system.

Sensitivity of the African neuropsychology battery memory subtests and learning slopes in discriminating APOE 4 and amyloid pathology in adult individuals in the Democratic Republic of Congo

Background

The current study examined the sensitivity of two memory subtests and their corresponding learning slope metrics derived from the African Neuropsychology Battery (ANB) to detect amyloid pathology and APOEε4 status in adults from Kinshasa, the Democratic Republic of the Congo.

Methods

85 participants were classified for the presence of β-amyloid pathology and based on allelic presence of APOEε4 using Simoa. All participants were screened using CSID and AQ, underwent verbal and visuospatial memory testing from ANB, and provided blood samples for plasma Aβ42, Aβ40, and APOE proteotype. Pearson correlation, linear and logistic regression were conducted to compare amyloid pathology and APOEε4 status with derived learning scores, including initial learning, raw learning score, learning over trials, and learning ratio.

Results

Our sample included 35 amyloid positive and 44 amyloid negative individuals as well as 42 without and 39 with APOEε4. All ROC AUC ranges for the prediction of amyloid pathology based on learning scores were low, ranging between 0.56-0.70 (95% CI ranging from 0.44-0.82). The sensitivity of all the scores ranged between 54.3-88.6, with some learning metrics demonstrating good sensitivity. Regarding APOEε4 prediction, all AUC values ranged between 0.60-0.69, with all sensitivity measures ranging between 53.8-89.7. There were minimal differences in the AUC values across learning slope metrics, largely due to the lack of ceiling effects in this sample.

Discussion

This study demonstrates that some ANB memory subtests and learning slope metrics can discriminate those that are normal from those with amyloid pathology and those with and without APOEε4, consistent with findings reported in Western populations.

Scalable plasma and digital cognitive markers for diagnosis and prognosis of Alzheimer's disease and related dementias

INTRODUCTION

With emergence of disease-modifying therapies, efficient diagnostic pathways are critically needed to identify treatment candidates, evaluate disease severity, and support prognosis. A combination of plasma biomarkers and brief digital cognitive assessments could provide a scalable alternative to current diagnostic work-up.

METHODS

We examined the accuracy of plasma biomarkers and a 10-minute supervised tablet-based cognitive assessment (Tablet-based Cognitive Assessment Tool Brain Health Assessment [TabCAT-BHA]) in predicting amyloid β positive (Aβ+) status on positron emission tomography (PET), concurrent disease severity, and functional decline in 309 older adults with subjective cognitive impairment (n = 49), mild cognitive impairment (n = 159), and dementia (n = 101).

RESULTS

Combination of plasma pTau181, Aβ42/40, neurofilament light (NfL), and TabCAT-BHA was optimal for predicting Aβ-PET positivity (AUC = 0.962). Whereas NfL and TabCAT-BHA optimally predicted concurrent disease severity, combining these with pTau181 and glial fibrillary acidic protein was most accurate in predicting functional decline.

DISCUSSION

Combinations of plasma and digital cognitive markers show promise for scalable diagnosis and prognosis of ADRD.

HIGHLIGHTS

The need for cost-efficient diagnostic and prognostic markers of AD is urgent. Plasma and digital cognitive markers provide complementary diagnostic contributions. Combination of these markers holds promise for scalable diagnosis and prognosis. Future validation in community cohorts is needed to inform clinical implementation.

Plasma SOMAmer proteomics of postoperative delirium

BACKGROUND

Postoperative delirium is prevalent in older adults and has been shown to increase the risk of long-term cognitive decline. Plasma biomarkers to identify the risk for postoperative delirium and the risk of Alzheimer's disease and related dementias are needed.

METHODS

This biomarker discovery case-control study aimed to identify plasma biomarkers associated with postoperative delirium. Patients aged ≥65 years undergoing major elective noncardiac surgery were recruited. The preoperative plasma proteome was interrogated with SOMAmer-based technology targeting 1433 biomarkers.

RESULTS

In 40 patients (20 with vs. 20 without postoperative delirium), a preoperative panel of 12 biomarkers discriminated patients with postoperative delirium with an accuracy of 97.5%. The final model of five biomarkers delivered a leave-one-out cross-validation accuracy of 80%. Represented biological pathways included lysosomal and immune response functions.

CONCLUSION

In older patients who have undergone major surgery, plasma SOMAmer proteomics may provide a relatively non-invasive benchmark to identify biomarkers associated with postoperative delirium.

Unveiling the autoreactome: Proteome-wide immunological fingerprints reveal the promise of plasma cell depleting therapy

The prevalence and burden of autoimmune and autoantibody mediated disease is increasing worldwide, yet most disease etiologies remain unclear. Despite numerous new targeted immunomodulatory therapies, comprehensive approaches to apply and evaluate the effects of these treatments longitudinally are lacking. Here, we leverage advances in programmable-phage immunoprecipitation (PhIP-Seq) methodology to explore the modulation, or lack thereof, of proteome-wide autoantibody profiles in both health and disease. We demonstrate that each individual, regardless of disease state, possesses a distinct set of autoreactivities constituting a unique immunological fingerprint, or "autoreactome", that is remarkably stable over years. In addition to uncovering important new biology, the autoreactome can be used to better evaluate the relative effectiveness of various therapies in altering autoantibody repertoires. We find that therapies targeting B-Cell Maturation Antigen (BCMA) profoundly alter an individual's autoreactome, while anti-CD19 and CD-20 therapies have minimal effects, strongly suggesting a rationale for BCMA or other plasma cell targeted therapies in autoantibody mediated diseases.

Presence of Preoperative Neurodegeneration Biofluid Markers in Patients with Postoperative Delirium

BACKGROUND

The pathophysiology of delirium is incompletely understood, including what molecular pathways are involved in brain vulnerability to delirium. This study examined whether preoperative plasma neurodegeneration markers were elevated in patients who subsequently developed postoperative delirium through a retrospective case-control study.

METHODS

Inclusion criteria were patients of 65 yr of age or older, undergoing elective noncardiac surgery with a hospital stay of 2 days or more. Concentrations of preoperative plasma P-Tau181, neurofilament light chain, amyloid β1-42 (Aβ42), and glial fibrillary acidic protein were measured with a digital immunoassay platform. The primary outcome was postoperative delirium measured by the Confusion Assessment Method. The study included propensity score matching by age and sex with nearest neighbor, such that each patient in the delirium group was matched by age and sex with a patient in the no-delirium group.

RESULTS

The initial cohort consists of 189 patients with no delirium and 102 patients who developed postoperative delirium. Of 291 patients aged 72.5 ± 5.8 yr, 50.5% were women, and 102 (35%) developed postoperative delirium. The final cohort in the analysis consisted of a no-delirium group (n = 102) and a delirium group (n = 102) matched by age and sex using the propensity score method. Of the four biomarkers assayed, the median value for neurofilament light chain was 32.05 pg/ml for the delirium group versus 23.7 pg/ml in the no-delirium group. The distribution of biomarker values significantly differed between the delirium and no-delirium groups (P = 0.02 by the Kolmogorov-Smirnov test) with the largest cumulative probability difference appearing at the biomarker value of 32.05 pg/ml.

CONCLUSIONS

These results suggest that patients who subsequently developed delirium are more likely to be experiencing clinically silent neurodegenerative changes before surgery, reflected by changes in plasma neurofilament light chain biomarker concentrations, which may identify individuals with a preoperative vulnerability to subsequent cognitive decline.

EDITOR’S PERSPECTIVE

Gamma neuromodulation improves episodic memory and its associated network in amnestic mild cognitive impairment: a pilot study

Amnestic mild cognitive impairment (aMCI) is a predementia stage of Alzheimer's disease associated with dysfunctional episodic memory and limited treatment options. We aimed to characterize feasibility, clinical, and biomarker effects of noninvasive neurostimulation for aMCI. 13 individuals with aMCI received eight 60-minute sessions of 40-Hz (gamma) transcranial alternating current stimulation (tACS) targeting regions related to episodic memory processing. Feasibility, episodic memory, and plasma Alzheimer's disease biomarkers were assessed. Neuroplastic changes were characterized by resting-state functional connectivity (RSFC) and neuronal excitatory/inhibitory balance. Gamma tACS was feasible and aMCI participants demonstrated improvement in multiple metrics of episodic memory, but no changes in biomarkers. Improvements in episodic memory were most pronounced in participants who had the highest modeled tACS-induced electric fields and exhibited the greatest changes in RSFC. Increased RSFC was also associated with greater hippocampal excitability and higher baseline white matter integrity. This study highlights initial feasibility and the potential of gamma tACS to rescue episodic memory in an aMCI population by modulating connectivity and excitability within an episodic memory network.

Genetic matching for time-dependent treatments: a longitudinal extension and simulation study

BACKGROUND

Longitudinal matching can mitigate confounding in observational, real-world studies of time-dependent treatments. To date, these methods have required iterative, manual re-specifications to achieve covariate balance. We propose a longitudinal extension of genetic matching, a machine learning approach that automates balancing of covariate histories. We examine performance by comparing the proposed extension against baseline propensity score matching and time-dependent propensity score matching.

METHODS

To evaluate comparative performance, we developed a Monte Carlo simulation framework that reflects a static treatment assigned at multiple time points. Data generation considers a treatment assignment model, a continuous outcome model, and underlying covariates. In simulation, we generated 1,000 datasets, each consisting of 1,000 subjects, and applied: (1) nearest neighbour matching on time-invariant, baseline propensity scores; (2) sequential risk set matching on time-dependent propensity scores; and (3) longitudinal genetic matching on time-dependent covariates. To measure comparative performance, we estimated covariate balance, efficiency, bias, and root mean squared error (RMSE) of treatment effect estimates. In scenario analysis, we varied underlying assumptions for assumed covariate distributions, correlations, treatment assignment models, and outcome models.

RESULTS

In all scenarios, baseline propensity score matching resulted in biased effect estimation in the presence of time-dependent confounding, with mean bias ranging from 29.7% to 37.2%. In contrast, time-dependent propensity score matching and longitudinal genetic matching achieved stronger covariate balance and yielded less biased estimation, with mean bias ranging from 0.7% to 13.7%. Across scenarios, longitudinal genetic matching achieved similar or better performance than time-dependent propensity score matching without requiring manual re-specifications or normality of covariates.

CONCLUSIONS

While the most appropriate longitudinal method will depend on research questions and underlying data patterns, our study can help guide these decisions. Simulation results demonstrate the validity of our longitudinal genetic matching approach for supporting future real-world assessments of treatments accessible at multiple time points.

A88 EVALUATING THE ACCEPTABILITY AND EFFICACY OF CYTOSPONGE FOR BARRETT'S ESOPHAGUS: A SINGLE CENTRE CROSS-SECTIONAL STUDY

Background

Barrett's Esophagus (BE) is a pre-malignant condition defined by the presence of metaplastic columnar epithelial cells above the gastroesophageal junction. Currently, diagnoses is made by endoscopy. Once metaplasia is present, there is 0.5% annual risk of progression to dysplasia and ultimately adenocarcinoma.

Cytosponge is a new device and technique to diagnose BE. Furthermore, this test has a strong safety profile. Research has suggested increased patient tolerance for the Cytosponge compared to endoscopy; this has not been demonstrated in a Canadian healthcare setting. Before Cytosponge test can be integrated in Canada, ideally, patient acceptability of this device should be evaluated.

Purpose

To assess patient acceptability, tolerability and integration of Cytosponge in the diagnosis of Barrett's Esophagus in a Canadian healthcare setting. We also assessed the ease of use and familiarity with Cytosponge.

Method

A single-centre, prospective cross-sectional study was conducted to evaluate the acceptability and comfort of patients undergoing Cytosponge procedure.

Outpatients referred for EGD for Barrett's Esophagus at St. Paul’s Hospital between 03/21-07/22 were included. 36 patients with BE have been enrolled in this project. Acceptability was evaluated through Visual Analogue Scale (VAS), Spielberger State Trait Anxiety Inventory (STAI), and Impact of Events Scale (IOES) on the day of procedure, day 7 post procedure and day 90 post procedure. Data from health care providers administering the Cytosponge were collected using the System Usability Scale (SUS).

One-way ANOVA and Tukey’s Honestly Significant Difference tests were completed to assess score differences between follow up.

Result(s)

A total of 36 patients met the inclusion criteria and consented to participate. Of these patients 81.6% were successful in swallowing Cytosponge, 18.4% were unsucessful. ANOVA test revealed statistically significant difference in VAS scores, F(3, 140) = 12.59, p < 0.0000005. There were significant differences in VAS between Day 0 and Day 7, p=0.0032. This was also seen in VAS between Day 0 vs Day 90, p=0.0017.

There were no statistically significant difference in mean STAI scores between different time points, F(3, 140) = 12.59, p=0.44. ANOVA test also showed statistical difference in IOES scores, F(2, 111) = 8.76, p<0.0005. There was statistical difference between day 0 compared to day 7 and between day 0 and day 90, p=0.0045, and p=0.00045 respectively.

Conclusion(s)

Our results demonstrate that Cytosponge is a well tolerated in a Canadian healthcare setting. Follow up scores of VAS and IOES were lower compared to day 0 suggesting that patients found Cytosponge acceptable. A score of 68 and above is considered to be above average on the SUS which measures usability of Cytosponge. The average SUS score in this sample was 65.3, this may suggest that there is a learning curve for health care providers to become familiar with Cytosponge. There were no complications with Cytosponge in this sample.

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Gastroenterology Institute of Research Institute

Disclosure of Interest

None Declared

Nocturnal respiratory abnormalities among ward-level postoperative patients as detected by the Capnostream 20p monitor: A blinded observational study

PURPOSE

This prospective observational study aimed to establish the frequency of postoperative nocturnal respiratory abnormalities among patients undergoing major surgery who received ward-level care. These abnormalities may have implications for postoperative pulmonary complications (PPCs).

METHODS

Eligible patients underwent blinded noninvasive continuous capnography with pulse oximetry using the Capnostream™ 20p monitor over the first postoperative night. All patients received oxygen supplementation and patient-controlled opioid analgesia. The primary outcome was the number of prolonged apnea events (PAEs), defined as end-tidal carbon dioxide (EtCO2) ≤5 mmHg for 30-120 seconds or EtCO2 ≤5 mmHg for >120 seconds with oxygen saturation (SpO2) <85%. Secondary outcomes were the proportion of recorded time that physiological indices were aberrant, including the apnea index (AI), oxygen desaturation index (ODI), integrated pulmonary index (IPI), and SpO2. Exploratory analysis was conducted to assess the associations between PAEs, PPCs, and pre-defined factors.

RESULTS

Among 125 patients who had sufficient data for analysis, a total of 1800 PAEs occurred in 67 (53.4%) patients. The highest quartile accounted for 89.1% of all events. Amongst patients who experienced any PAEs, the median (IQR) number of PAE/patient was four (2-12). As proportions of recorded time (median (IQR)), AI, ODI, and IPI were aberrant for 12.4% (0-43.2%), 19.1% (2.0-57.1%), and 11.5% (3.1-33.3%) respectively. Only age, ARISCAT, and opioid consumption/kg were associated with PPCs.

CONCLUSIONS

PAE and aberrant indices were frequently detected on the first postoperative night. However, they did not correlate with PPCs. Future research should investigate the significance of detected aberrations.

Resectability of bilobar liver tumours after simultaneous portal and hepatic vein embolization versus portal vein embolization alone: meta-analysis

BACKGROUND

Many patients with bi-lobar liver tumours are not eligible for liver resection due to an insufficient future liver remnant (FLR). To reduce the risk of posthepatectomy liver failure and the primary cause of death, regenerative procedures intent to increase the FLR before surgery. The aim of this systematic review is to provide an overview of the available literature and outcomes on the effectiveness of simultaneous portal and hepatic vein embolization (PVE/HVE) versus portal vein embolization (PVE) alone.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Embase up to September 2022. The primary outcome was resectability and the secondary outcome was the FLR volume increase.

RESULTS

Eight studies comparing PVE/HVE with PVE and six retrospective PVE/HVE case series were included. Pooled resectability within the comparative studies was 75 per cent in the PVE group (n = 252) versus 87 per cent in the PVE/HVE group (n = 166, OR 1.92 (95% c.i., 1.13-3.25)) favouring PVE/HVE (P = 0.015). After PVE, FLR hypertrophy between 12 per cent and 48 per cent (after a median of 21-30 days) was observed, whereas growth between 36 per cent and 67 per cent was reported after PVE/HVE (after a median of 17-31 days). In the comparative studies, 90-day primary cause of death was similar between groups (2.5 per cent after PVE versus 2.2 per cent after PVE/HVE), but a higher 90-day primary cause of death was reported in single-arm PVE/HVE cohort studies (6.9 per cent, 12 of 175 patients).

CONCLUSION

Based on moderate/weak evidence, PVE/HVE seems to increase resectability of bi-lobar liver tumours with a comparable safety profile. Additionally, PVE/HVE resulted in faster and more pronounced hypertrophy compared with PVE alone.

Patient-reported outcomes in a linguistically diverse cancer population: Addressing barriers to access

168

Background: The census metropolitan area served by BC Cancer is Vancouver which has a population of 2.4 million. Census Canada noted the mother tongue learned in childhood and still spoken was: 54% English, 17% Indo-European, 16% Chinese, 10% Indo-Iranian, 3% English+other language, 2% other. At BC Cancer, implementation of patient reported outcomes (PROs) was launched 1 year ago with consideration of preferred language. Our goal was to examine the implementation of PROs with respect to equity of access and language preferences. Methods: BC Cancer Vancouver implemented PROs including the Edmonton Symptom Assessment Scale Revised, Canadian Problem Checklist and EQ5D in April 2021 using a web-based platform. A 1-year cohort was reviewed for patients’ mother tongue and the language used for the PROs. Qualitative interviews were undertaken for non-English mother tongue patients to ask for preferred language of PROs and reasons for the choice if mother tongue was not selected. Results: 86 patients were enrolled in the PRO program. Baseline characteristics: 66% female, age 30% < 60/ 31% 60-69/ 39% >70, primary site 54% lung/ 34% colorectal/ 18% other. Ethnic origin: 53% North American and European, 40% East and Southeast Asian, 2% Latin/Central and South American, 3% South Asian, 1% Indigenous, 1% other. Mother tongue: 52% English, 48% non-English (39% English proficient, 9% low English proficiency). Patient preferred language for PROs: 81% English, 11% Chinese, 7% other. Reasons for non-English mother tongue preference for English language included comfort with written English, use of family assistance completing questionnaires for both language and familiarity with electronic devices. Conclusions: In the Vancouver linguistically diverse cancer population, the majority of patients preferred English language PROs. Reasons for this include proficiency in the written language and the use of family members to complete the questionnaires. With 39% of patients over the age of 70 in our study, the use of electronic devices for completion may have introduced an additional barrier to access. In clinic iPad questionnaires with nursing and care aide support have been introduced to help address this gap. Clinical trial information: NCT05057234.

The influence of anastomotic techniques on postoperative anastomotic complications: Results of the Oesophago-Gastric Anastomosis Audit

BACKGROUND

The optimal anastomotic techniques in esophagectomy to minimize rates of anastomotic leakage and conduit necrosis are not known. The aim of this study was to assess whether the anastomotic technique was associated with anastomotic failure after esophagectomy in the international Oesophago-Gastric Anastomosis Audit cohort.

METHODS

This prospective observational multicenter cohort study included patients undergoing esophagectomy for esophageal cancer over 9 months during 2018. The primary exposure was the anastomotic technique, classified as handsewn, linear stapled, or circular stapled. The primary outcome was anastomotic failure, namely a composite of anastomotic leakage and conduit necrosis, as defined by the Esophageal Complications Consensus Group. Multivariable logistic regression modeling was used to identify the association between anastomotic techniques and anastomotic failure, after adjustment for confounders.

RESULTS

Of the 2238 esophagectomies, the anastomosis was handsewn in 27.1%, linear stapled in 21.0%, and circular stapled in 51.9%. Anastomotic techniques differed significantly by the anastomosis sites (P < .001), with the majority of neck anastomoses being handsewn (69.9%), whereas most chest anastomoses were stapled (66.3% circular stapled and 19.3% linear stapled). Rates of anastomotic failure differed significantly among the anastomotic techniques (P < .001), from 19.3% in handsewn anastomoses, to 14.0% in linear stapled anastomoses, and 12.1% in circular stapled anastomoses. This effect remained significant after adjustment for confounding factors on multivariable analysis, with an odds ratio of 0.63 (95% CI, 0.46-0.86; P = .004) for circular stapled versus handsewn anastomosis. However, subgroup analysis by anastomosis site suggested that this effect was predominantly present in neck anastomoses, with anastomotic failure rates of 23.2% versus 14.6% versus 5.9% for handsewn versus linear stapled anastomoses versus circular stapled neck anastomoses, compared with 13.7% versus 13.8% versus 12.2% for chest anastomoses.

CONCLUSIONS

Handsewn anastomoses appear to be independently associated with higher rates of anastomotic failure compared with stapled anastomoses. However, this effect seems to be largely confined to neck anastomoses, with minimal differences between techniques observed for chest anastomoses. Further research into standardization of anastomotic approach and techniques may further improve outcomes.

Defining a Core Data Set for the Economic Evaluation of Precision Oncology

OBJECTIVES

Precision oncology is generating vast amounts of multiomic data to improve human health and accelerate research. Existing clinical study designs and attendant data are unable to provide comparative evidence for economic evaluations. This lack of evidence can cause inconsistent and inappropriate reimbursement. Our study defines a core data set to facilitate economic evaluations of precision oncology.

METHODS

We conducted a literature review of economic evaluations of next-generation sequencing technologies, a common application of precision oncology, published between 2005 and 2018 and indexed in PubMed (MEDLINE). Based on this review, we developed a preliminary core data set for informal expert feedback. We then used a modified-Delphi approach with individuals involved in implementation and evaluation of precision medicine, including 2 survey rounds followed by a final voting conference to refine the data set.

RESULTS

Two authors determined that variation in published data elements was reached after abstraction of 20 economic evaluations. Expert consultation refined the data set to 83 unique data elements, and a multidisciplinary sample of 46 experts participated in the modified-Delphi process. A total of 68 elements (81%) were selected as required, spanning demographics and clinical characteristics, genomic data, cancer treatment, health and quality of life outcomes, and resource use.

CONCLUSIONS

Cost-effectiveness analyses will fail to reflect the real-world impacts of precision oncology without data to accurately characterize patient care trajectories and outcomes. Data collection in accordance with the proposed core data set will promote standardization and enable the generation of decision-grade evidence to inform reimbursement.

Plasma neurofilament light chain levels suggest neuroaxonal stability following therapeutic remyelination in people with multiple sclerosis

BACKGROUND

Chronic demyelination is a major contributor to axonal vulnerability in multiple sclerosis (MS). Therefore, remyelination could provide a potent neuroprotective strategy. The ReBUILD trial was the first study showing evidence for successful remyelination following treatment with clemastine in people with MS (pwMS) with no evidence of disease activity or progression (NEDAP). Whether remyelination was associated with neuroprotection remains unexplored.

METHODS

Plasma neurofilament light chain (NfL) levels were measured from ReBUILD trial's participants. Mixed linear effect models were fit for individual patients, epoch and longitudinal measurements to compare NfL concentrations between samples collected during the active and placebo treatment period.

RESULTS

NfL concentrations were 9.6% lower in samples collected during the active treatment with clemastine (n=53, geometric mean=6.33 pg/mL) compared to samples collected during treatment with placebo (n=73, 7.00 pg/mL) (B=-0.035 [-0.068 to -0.001], p=0.041). Applying age- and body mass index-standardised NfL Z-scores and percentiles revealed similar results (0.04 vs 0.35, and 27.5 vs 33.3, p=0.023 and 0.042, respectively). Higher NfL concentrations were associated with more delayed P100 latencies (B=1.33 [0.26 to 2.41], p=0.015). In addition, improvement of P100 latencies between visits was associated with a trend for lower NfL values (B=0.003 [-0.0004 to 0.007], p=0.081). Based on a Cohen's d of 0.248, a future 1:1 parallel-arm placebo-controlled study using a remyelinating agent with comparable effect as clemastine would need 202 subjects per group to achieve 80% power.

CONCLUSIONS

In pwMS, treatment with the remyelinating agent clemastine was associated with a reduction of blood NfL, suggesting that neuroprotection is achievable and measurable with therapeutic remyelination.

TRIAL REGISTRATION NUMBER

NCT02040298.

Life-cycle health technology assessment for precision oncology

e18704

Background: Rapid advances in precision oncology challenge timely and sustainable reimbursement decisions. Life-cycle health technology assessment (LC-HTA) can enable conditional patient access to promising precision oncology innovations alongside evidence development. Our objective was to create a life-cycle evaluative framework, called PRecision oncology Evidence Development in Cancer Treatment (PREDiCT). Methods: Through an iterative, health system and stakeholder-informed approach, we designed our LC-HTA framework. Elements supporting data and evidence generation were subsequently implemented within British Columbia, Canada’s provincial cancer control system. Our development, refinement, and pilot implementation process included a structured literature review, multi-disciplinary international expert consultation, a formal gap assessment, and a series of pan-Canadian inter-disciplinary stakeholder workshops to refine framework elements. Results: We engaged n = 15 pan-Canadian and international stakeholders to co-develop the LC-HTA framework. Defining framework components include: (a) managed access that defines the time horizon and pricing conditions of real-world healthcare system trialing; (b) collection of core data elements required to enable economic evaluation of precision oncology using real world data; (c) externally leveraged real world data and evidence generation to determine comparative effectiveness, cost-effectiveness, and the value of conducting additional research; and (d) data interpretation updating decisions, including investment, continued evaluation, or disinvestment from managed access. Key to the success of early framework implementation is the expansion of infrastructure to enable routine collection and linkage of genomic sequencing and cancer treatment data, patient quality of life and clinical outcomes, as well as health resource use spanning the diagnostic, treatment, and follow up trajectory. Conclusions: Sustainable integration of precision oncology requires the design and implementation of learning healthcare systems (LHS) that integrate genomic data with other health information. LC-HTA moves beyond static estimates of clinical and cost-effectiveness to continuously generate evidence that reduces evidentiary uncertainty and supports life-cycle decisions. We are embarking on a PREDiCT pilot to implement the framework in real-time to demonstrate the ability of real-world data to support life cycle evaluation.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P &lt; 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P &lt; 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Hepatic and renal function impact concentrations of plasma biomarkers of neuropathology

Introduction

The impact of hepatorenal function on plasma biomarkers of neuropathology is unknown. Herein, we measured several plasma biomarkers in patients with cirrhosis.

Methods

Plasma phosphorylated tau (p-tau181), neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP), total tau (t-tau), and ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) were measured in 135 adults with cirrhosis and 22 healthy controls using Simoa. Within cirrhosis, associations between biomarkers and hepatorenal function were explored using linear regression.

Results

p-tau181, NfL, t-tau, and UCHL1 were increased 2- to 4-fold in cirrhosis, whereas GFAP was not increased. Within cirrhosis, creatinine moderately correlated with p-tau181 (β = 0.75, P < .01), NfL (β = 0.32, P < .01), and t-tau (β = 0.31, P < .01), but not GFAP (β = -0.01, P = .88) or UCHL1 (β = -0.05, P = .60), whereas albumin showed weak, inverse correlations: p-tau181 (β = -0.18, P < .01), NfL (β = -0.22, P < .01), GFAP (β = -0.17, P < .05), t-tau (β = -0.20, P = .02), and UCHL1 (β = -0.15, P = .09).

Conclusions

Elevated p-tau181, NfL, and t-tau in cirrhosis were associated with renal impairment and hypoalbuminemia, suggesting that hepatorenal function may be important when interpreting plasma biomarkers of neuropathology.

Characteristics of Older Adults Accessing Medical Assistance in Dying (MAiD): a Descriptive Study

Background

Medical Assistance in Dying (MAiD) is an end-of-life option for Canadians accounting for 2% of all deaths in Canada in 2019. Adults over 80 years old represent a significant proportion of these deaths, yet little is known about how they compare with their younger counterparts.

Methods

This study retrospectively reviewed our tertiary care institution’s MAiD database to compare MAiD recipients <65, 65–80, and >80 years of age. Extracted data included basic demographics, illness characteristics, functional status, social living arrangements/contacts, and outcomes of MAiD assessments.

Results

Of 267 patients assessed for MAiD, 38.2% were over 80. Compared to the younger groups, those over 80 were more likely to be female, to live alone, and to be widowed; however, they did not self-identify as ‘socially isolated’. The majority fit into the illness categories of malignancy, cardiopulmonary or neurologic diseases, but those over 80 were more likely to have other more chronic/subacute conditions leading to the MAiD request.

Conclusions

Older adults accessing MAiD are distinct in that they tend to be increasingly frail and without a predominant underlying diagnosis as compared with younger adults, but rather have an accumulation of losses resulting in global functional decline and subsequent loss of autonomy and independence.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

A hepatitis C elimination model in healthcare for the homeless organization: A novel reflexive laboratory algorithm and equity assessment

BACKGROUND

Reaching World Health Organization hepatitis C (HCV) elimination targets requires diagnosis and treatment of people who use drugs (PWUD) with direct acting antivirals (DAAs). PWUD experience challenges engaging in HCV treatment, including needing multiple provider and laboratory appointments. Women, minoritized racial communities, and homeless individuals are less likely to complete treatment.

METHODS

We implemented a streamlined opt-out HCV screening and linkage-to-care program in two healthcare for the homeless clinics and a medically supported withdrawal center. Front-line staff initiated a single-order reflex laboratory bundle combining screening, confirmation, and pre-treatment laboratory evaluation from a single blood draw. Multinomial logistic regression models identified characteristics influencing movement through each stage of the HCV treatment cascade. Multiple logistic regression models identified patient characteristics associated with HCV care cascade progression and Cox proportional hazards models assessed time to initiation of DAAs.

RESULTS

Of 11,035 clients engaged in services between May 2017 and March 2020, 3,607 (32.7%) were screened. Of those screened, 1,020 (28.3%) were HCV PCR positive. Of those with detectable RNA, 712 (69.8%) initiated treatment and 670 (94.1%) completed treatment. Of those initiating treatment, 407 (57.2%) achieved SVR12. There were eight treatment failures and six reinfections. In the unadjusted model, the bundle intervention was associated with increased care cascade progression, and in the survival analysis, decreased time to initiation; these differences were attenuated in the adjusted model. Women were less likely to complete treatment and SVR12 labs than men. Homelessness increased likelihood of screening and diagnosis but was negatively associated with completing SVR12 labs. Presence of opioid and stimulant use disorder diagnoses predicted increased care cascade progression.

CONCLUSIONS

The laboratory bundle and referral pathways improved treatment initiation, time to initiation, and movement across the cascade. Despite overall population improvements, women and homeless individuals experienced important gaps across the HCV care cascade.

Clinical and cost outcomes following genomics-informed treatment for advanced cancers

BACKGROUND

Single-arm trials are common in precision oncology. Owing to the lack of randomized counterfactual, resultant data are not amenable to comparative outcomes analyses. Difference-in-difference (DID) methods present an opportunity to generate causal estimates of time-varying treatment outcomes. Using DID, our study estimates within-cohort effects of genomics-informed treatment versus standard care on clinical and cost outcomes.

METHODS

We focus on adults with advanced cancers enrolled in the single-arm BC Cancer Personalized OncoGenomics program between 2012 and 2017. All individuals had a minimum of 1-year follow up. Logistic regression explored baseline differences across patients who received a genomics-informed treatment versus a standard care treatment after genomic sequencing. DID estimated the incremental effects of genomics-informed treatment on time to treatment discontinuation (TTD), time to next treatment (TTNT), and costs. TTD and TTNT correlate with improved response and survival.

RESULTS

Our study cohort included 346 patients, of whom 140 (40%) received genomics-informed treatment after sequencing and 206 (60%) received standard care treatment. No significant differences in baseline characteristics were detected across treatment groups. DID estimated that the incremental effect of genomics-informed versus standard care treatment was 102 days (95% CI: 35, 167) on TTD, 91 days (95% CI: -9, 175) on TTNT, and CAD$91,098 (95% CI: $46,848, $176,598) on costs. Effects were most pronounced in gastrointestinal cancer patients.

CONCLUSIONS

Genomics-informed treatment had a statistically significant effect on TTD compared to standard care treatment, but at increased treatment costs. Within-cohort evidence generated through this single-arm study informs the early-stage comparative effectiveness of precision oncology.

Safety of exercise training in multiple sclerosis: a protocol for an updated systematic review and meta-analysis

BACKGROUND

There has been an exponential growth in the number of clinical research studies regarding exercise training in multiple sclerosis, and literature reviews and meta-analyses have documented the many benefits of exercise training. This research further requires careful review for documenting the safety of exercise training in multiple sclerosis, as clarity on safety represents a major hurdle in the clinical prescription of exercise behaviour.

OBJECTIVES

To enhance understanding of the feasibility of exercise in multiple sclerosis, we (1) provide a protocol of a systematic review and meta-analysis that summarises rates and risks of clinical relapse, adverse events (i.e., an unfavourable outcome that occurs during the intervention delivery time period), and serious adverse events (i.e., an untoward occurrence that results in death or is life threatening, requires hospitalisation, or results in disability during the intervention delivery time period), as well as retention, adherence, and compliance, from randomised controlled trials of exercise training in persons with multiple sclerosis; and (2) identify moderators of relapse, adverse events, and serious adverse event rates.

METHODS

Eight field-relevant databases will be searched electronically. Studies that involve a randomised controlled trial of exercise training (with non-exercise, non-pharmacological, comparator), report on safety outcomes, and include adults with multiple sclerosis will be included. Rates and relative risks of the three primary outcomes (relapse, adverse event, and serious adverse event) will be calculated and reported each with standard error and 95% confidence interval. Random-effects meta-analysis will estimate mean population relative risk for outcomes. Potential sources of variability, including participant characteristics, features of the exercise stimulus, and comparison condition, will be examined with random-effects meta-regression with maximum likelihood estimation.

DISCUSSION

The results from this systematic review and meta-analysis will inform and guide healthcare practitioners, researchers, and policymakers on the safety of exercise training in persons with multiple sclerosis. Where possible, we will identify the impact of exercise type, exercise delivery style, participant disability level, and the prescription of exercise guidelines, on the safety of exercise training. The result will identify critical information on the safety of exercise in persons with multiple sclerosis, while also identifying gaps in research and setting priorities for future enquiries.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2020 CRD42020190544.

Mortality from esophagectomy for esophageal cancer across low, middle, and high-income countries: An international cohort study

BACKGROUND

No evidence currently exists characterising global outcomes following major cancer surgery, including esophageal cancer. Therefore, this study aimed to characterise impact of high income countries (HIC) versus low and middle income countries (LMIC) on the outcomes following esophagectomy for esophageal cancer.

METHOD

This international multi-center prospective study across 137 hospitals in 41 countries included patients who underwent an esophagectomy for esophageal cancer, with 90-day follow-up. The main explanatory variable was country income, defined according to the World Bank Data classification. The primary outcome was 90-day postoperative mortality, and secondary outcomes were composite leaks (anastomotic leak or conduit necrosis) and major complications (Clavien-Dindo Grade III - V). Multivariable generalized estimating equation models were used to produce adjusted odds ratios (ORs) and 95% confidence intervals (CI95%).

RESULTS

Between April 2018 to December 2018, 2247 patients were included. Patients from HIC were more significantly older, with higher ASA grade, and more advanced tumors. Patients from LMIC had almost three-fold increase in 90-day mortality, compared to HIC (9.4% vs 3.7%, p < 0.001). On adjusted analysis, LMIC were independently associated with higher 90-day mortality (OR: 2.31, CI95%: 1.17-4.55, p = 0.015). However, LMIC were not independently associated with higher rates of anastomotic leaks (OR: 1.06, CI95%: 0.57-1.99, p = 0.9) or major complications (OR: 0.85, CI95%: 0.54-1.32, p = 0.5), compared to HIC.

CONCLUSION

Resections in LMIC were independently associated with higher 90-day postoperative mortality, likely reflecting a failure to rescue of these patients following esophagectomy, despite similar composite anastomotic leaks and major complication rates to HIC. These findings warrant further research, to identify potential issues and solutions to improve global outcomes following esophagectomy for cancer.

Comparison of short-term outcomes from the International Oesophago-Gastric Anastomosis Audit (OGAA), the Esophagectomy Complications Consensus Group (ECCG), and the Dutch Upper Gastrointestinal Cancer Audit (DUCA)

BACKGROUND

The Esophagectomy Complications Consensus Group (ECCG) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA) have set standards in reporting outcomes after oesophagectomy. Reporting outcomes from selected high-volume centres or centralized national cancer programmes may not, however, be reflective of the true global prevalence of complications. This study aimed to compare complication rates after oesophagectomy from these existing sources with those of an unselected international cohort from the Oesophago-Gastric Anastomosis Audit (OGAA).

METHODS

The OGAA was a prospective multicentre cohort study coordinated by the West Midlands Research Collaborative, and included patients undergoing oesophagectomy for oesophageal cancer between April and December 2018, with 90 days of follow-up.

RESULTS

The OGAA study included 2247 oesophagectomies across 137 hospitals in 41 countries. Comparisons with the ECCG and DUCA found differences in baseline demographics between the three cohorts, including age, ASA grade, and rates of chronic pulmonary disease. The OGAA had the lowest rates of neoadjuvant treatment (OGAA 75.1 per cent, ECCG 78.9 per cent, DUCA 93.5 per cent; P < 0.001). DUCA exhibited the highest rates of minimally invasive surgery (OGAA 57.2 per cent, ECCG 47.9 per cent, DUCA 85.8 per cent; P < 0.001). Overall complication rates were similar in the three cohorts (OGAA 63.6 per cent, ECCG 59.0 per cent, DUCA 62.2 per cent), with no statistically significant difference in Clavien-Dindo grades (P = 0.752). However, a significant difference in 30-day mortality was observed, with DUCA reporting the lowest rate (OGAA 3.2 per cent, ECCG 2.4 per cent, DUCA 1.7 per cent; P = 0.013).

CONCLUSION

Despite differences in rates of co-morbidities, oncological treatment strategies, and access to minimal-access surgery, overall complication rates were similar in the three cohorts.

Readiness of Healthcare Systems to Generate Real-World Evidence: Reliability of CT Radiographic End Points for Evaluation of First-Line Systemic Treatment

PURPOSE

Regulatory agencies such as the US Food and Drug Administration and health technology assessment bodies are increasingly using real-world evidence (RWE). The ability of healthcare systems to reliably generate response rate and progression-free survival from real-world data is unknown. We examined the capacity of a single-payer system to provide RWE by evaluating the frequency of computed tomography (CT) imaging during standard first-line metastatic systemic treatment of breast, colorectal, and lung cancer.

METHODS

A 1-year cohort of patients with metastatic-at-diagnosis breast, colorectal, and lung cancer treated with first-line systemic therapy (excluding hormone therapy) referred to BC Cancer in 2016 was retrospectively reviewed for first-line treatment and CT imaging. Duration of first-line treatment was calculated from the first to the last dose of therapy. CT imaging was counted from the start of therapy to 8 weeks after the last therapy dose.

RESULTS

A cohort of 664 patients was identified from the BC Cancer Registry. Distribution of metastatic disease at diagnosis was breast (n = 82), colorectal (n = 214), and lung (n = 368) cancer. For breast, colorectal, and lung cancer, there was a baseline CT within 4 weeks of treatment initiation in 59%, 51%, and 48% of patients, with median duration of first-line treatment of 14.6, 25.3, and 11.9 weeks and median CT imaging interval of 9.1, 9.0, and 6.1 weeks.

CONCLUSION

In our publicly funded healthcare system, availability of baseline CT imaging was 48% to 59% and the frequency of assessment ranged from 6.1 to 9.1 weeks, subject to patterns of practice and resource availability. Our system was not capable of providing RWE for image-based end points. Alternative end points should be considered to capitalize on the wealth of real-world data.

Readiness of health care systems to generate RWE: Frequency of radiographic imaging of metastatic disease during first-line systemic therapy

268

Background: Regulatory and Health Technology Assessment (HTA) agencies are increasingly using real world data (RWD) to support real world evidence (RWE), but the readiness of healthcare systems to reliably generate RWE is unknown. As a quality assurance measure we examined the preparedness of a single payer system to provide RWE by evaluating the frequency of CT imaging during standard first line metastatic systemic treatment of breast, colorectal (CRC) and lung cancer. Methods: A 1-year cohort of de novo metastatic breast, CRC, lung cancer patients treated with first line systemic therapy (excluding hormone therapy) referred to BC Cancer in 2016 was retrospectively reviewed. Duration of first line treatment was calculated from first to last dose of therapy. Baseline CT included imaging within 8 weeks prior to and 3 weeks after treatment initiation (first cycle). Last CT included imaging up to 8 weeks after the last dose of therapy. Results: A cohort of 675 patients was identified from the BC Cancer Registry. The distribution of de novo metastatic disease at diagnosis was lung (n = 379), CRC (n = 214) followed by breast cancer (n = 82). Conclusions: In our publicly funded health care system, baseline CT scans within 4 weeks prior to treatment ranged from 57-72%. The median CT imaging interval during first line metastatic treatment was ranged from 7.9-11.3 weeks. RWD from routine clinical practice differs significantly from clinical trials, the gold standard for regulatory and HTA assessments. Population-based data may contribute to RWE with caution due to limitations imposed by clinical practice. [Table: see text]

FRI0314 ANNUAL DIAGNOSTIC PREVALENCE OF ANKYLOSING SPONDYLITIS (AS) IN THE UNITED STATES USING MEDICARE AND MARKETSCAN DATA

Background:

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that affects the axial skeleton and sacroiliac joints, and can be classified as ankylosing spondylitis (AS) or non-radiographic (nr)-axSpA.1A 2016 analysis estimated the US diagnostic prevalence of axSpA to be 0.2% and AS to be 0.1%.2Previous studies use disparate populations and diagnostic definitions;3,4it is therefore unclear how AS prevalence has changed over time.

Objectives:

To investigate the annual diagnostic prevalence of AS in US healthcare insurance claims databases.

Methods:

A retrospective, observational cohort study was conducted using 2006–2014 data from US Medicare Fee-for-Service Claims (5% random sample of all enrolled patients [pts]) and Truven MarketScan®. Eligible pts were ≥20 years (yrs) and had ≥6 months of continuous medical and pharmacy enrolment prior to diagnosis. Diagnoses used relevant International Classification of Disease, 9thversion (ICD-9) diagnosis codes: ICD-9 720.x [x=any number] for “AS and other inflammatory spondylopathies [SpA]” or 720.0 for “AS”. Two diagnosis definitions were used: Definition 1, ≥1 relevant ICD-9 code from hospital discharge or ≥2 from rheumatologist visit; Definition 2, ≥1 relevant ICD-9 code from hospital discharge or rheumatologist visit. Annual diagnostic prevalence of SpA/AS was calculated as “number of enrolled pts who met the definition of SpA/AS within each calendar yr and had full insurance coverage (medical and pharmacy)”, divided by “total number of pts with full insurance coverage in the same yr”. A primary analysis of SpA prevalence rates used Definitions 1 and 2, followed by a sensitivity analysis for AS prevalence rates using only Definition 2. All prevalence rates are shown per 10,000 pts enrolled.

Results:

The annual diagnostic prevalence of SpA appeared to increase from 2006–2014 (Table). Similarly, the sensitivity analysis showed the annual diagnostic prevalence of AS appeared to increase during the period from 2006 (Medicare: 2.87/10,000 pts [n=501,031]; MarketScan: 1.37/10,000 pts [n=17,562,637]) to 2014 (Medicare: 4.77/10,000 pts [n=1,046,107]; MarketScan: 2.14/10,000 pts [n=34,553,135];Figure).

Conclusion:

The apparent increase in diagnostic prevalence of SpA and AS during the period from 2006–‍2014 may be a consequence of increased awareness and availability of effective treatments. Furthermore, the 2009 Assessment of SpondyloArthritis international Society development of the axSpA classification criteria to include pts with both established AS and nr-axSpA may have accelerated this increase.5

References:

[1]Strand V. Mayo Clin Proc 2017;92:555–64;

[2]Curtis J. Perm J 2016;20:15–151;

[3]Reveille J. Arthritis Care Res (Hoboken) 2012;64:905–10;

[4]Danve A. Clin Rheumatol 2019;38:625–34;

[5]Rudwaleit M. Ann Rheum Dis 2009;68:777–83.

Table.

Prevalence of SpA by calendar year and data source

Medicare (5% random sample)MarketScanCalendar yrTotal number of eligible ptsPrevalence/10,000 ptsTotal number of eligible ptsPrevalence/10,000 ptsDefinition 1Definition 2Definition 1Definition 22006501,0314.397.6217,562,6371.332.172007816,9705.258.7219,518,0661.472.372008825,4454.898.7828,603,5251.582.532009830,9675.229.2131,757,0691.903.092010844,5285.499.9031,126,1721.963.172011879,9966.3010.7138,295,1211.943.112012921,9946.1710.8840,320,4371.913.0420131,032,8276.7410.8233,826,0412.003.1920141,046,1076.5210.8534,553,1352.213.51

Medicare data included a 5% random sample of all enrolled pts age ≥20 yrs. pts: patients; SpA: ankylosing spondylitis and other inflammatory spondylopathies; yr: year.

Acknowledgments:

This study was funded by UCB Pharma. Editorial services were provided by Costello Medical.

Disclosure of Interests:

Jeffrey Curtis Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Corona, Crescendo, Genentech, Janssen, Pfizer, Roche and UCB Pharma, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Corona, Crescendo, Genentech, Janssen, Pfizer, Roche and UCB Pharma, Kevin Winthrop Grant/research support from: Bristol-Myers Squibb, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, Galapagos, Gilead, GSK, Pfizer Inc, Roche, UCB, Benjamin Chan: None declared, Sarah Siegel: None declared, Jeffrey Stark Employee of: UCB Pharma, Robert Suruki Employee of: UCB Pharma, Rhonda Bohn Consultant of: UCB Pharma, Fenglong Xie: None declared, Huifeng Yun Grant/research support from: Bristol-Myers Squibb and Pfizer, Lang Chen: None declared, Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB

SAT0370 TUMOUR NECROSIS FACTOR INHIBITOR THERAPY DOES NOT REDUCE THE INCIDENCE OF COMORBIDITIES AND EXTRA-ARTICULAR MANIFESTATIONS IN ANKYLOSING SPONDYLITIS: AN ANALYSIS OF THREE US CLAIMS DATABASES

Background:

Comorbidities and extra-articular manifestations (EAMs) substantially increase disease burden and mortality risk in patients (pts) with ankylosing spondylitis (AS).1,2Tumour necrosis factor inhibitors (TNFi) are highly efficacious and effective in AS treatment (tx), and are used after inadequate response to non-steroidal anti-inflammatory drugs.3,4However, the impact of TNFi on the incidence of comorbidities and EAMs in pts with AS is unknown.5

Objectives:

To determine the incidence of comorbidities and EAMs in TNFi vs non-TNFi treated pts with AS in the US.

Methods:

This was a retrospective, observational cohort study using data from 3 healthcare insurance claims databases: Multi-Payer Claims Database (MPCD Optum Insight; 2007–2010), Truven MarketScan®(2010–2014) and US Medicare Fee-for-Service Claims database (2006–2014). Eligible pts: ≥20 years (yrs) for MarketScan/MPCD or ≥65 yrs for Medicare, had an AS diagnosis (≥2 International Classification of Disease, 9thversion [ICD-9] diagnosis codes of 720.0 from a rheumatologist) and ≥12 months’ continuous medical and pharmacy enrolment prior to AS diagnosis (AS index date). Pts with AS not receiving tx were excluded. Tx exposure was reported from the first date of a new prescription/administration of an AS tx (no prior exposure) after the AS index date. Crude incidence rates (IR; shown as cases/100 pt-yrs) were calculated for EAMs (uveitis, psoriasis [PSO], psoriatic arthritis [PsA], inflammatory bowel disease [IBD]), with follow-up until the earliest of: death, lost medical/pharmacy coverage, study period end, first outcome occurrence, tx switch/discontinuation. Hazard ratios (HRs) of comorbidities (hospitalised infection, solid cancers) and EAMs for propensity score (PS)-matched pt groups were calculated using Cox proportional hazard regression models. Pts with the specific comorbidity/EAM of interest prior to AS index date were excluded. PS analyses assessed probability of TNFi initiation vs non-TNFi tx and adjusted for factors including comorbidities and demographics. HRs with confidence intervals crossing 1 are not reported.

Results:

20,460 pts with AS were eligible (MPCD: 2,384; MarketScan: 9,032; Medicare: 9,044). In all databases, crude IR of EAMs were higher for TNFi vs non-TNFi treated pts (Figure 1). In the PS-matched cohort, incidences of hospitalised infections were lower in TNFi vs non-TNFi treated pts from the MarketScan and Medicare databases (Figure 2). Higher incidences of solid cancers and EAMs were observed in TNFi vs non-TNFi treated pts; Medicare data (Figure 2). A higher risk of PsA and PSO was seen in TNFi vs non-TNFi treated pts; MarketScan data (Figure 2). PS-matched cohort data from the MPCD database were non-significant.

Conclusion:

Despite strong efficacy in treating AS-related signs and symptoms, similar incidence of comorbidities and increased incidence of some EAMs (IBD, PSO/PsA, uveitis) was seen in TNFi vs non-TNFi treated pts in the PS-matched analyses. This may be due to channelling of pts with more severe AS to receive TNFi, despite the PS-matched analysis aiming to overcome this. Moreover, prior medical history of Medicare pts may not be captured in the database, as pts are typically older with longer disease durations. While these results confirm previous findings,6a prospective observational study is required to generalise to pts outside the US.

References:

[1]Stolwijk C. Ann Rheum Dis 2015;74:1373–8;

[2]Bremander A. Arthritis Care Res 2011;63:550–6;

[3]Braun J. Scand J Rheumatol 2005;34:178–90;

[4]Ji X. Front Pharmacol 2019;10:1476;

[5]Maxwell LJ. Cochrane Database Syst Rev 2015:CD005468;

[6]Walsh J. J Pharm Health Serv Res 2018;9:115–21.

Acknowledgments:

This study was funded by UCB Pharma. Editorial services were provided by Costello Medical.

Disclosure of Interests:

Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Kevin Winthrop Grant/research support from: Bristol-Myers Squibb, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, Galapagos, Gilead, GSK, Pfizer Inc, Roche, UCB, Rhonda Bohn Consultant of: UCB Pharma, Benjamin Chan: None declared, Robert Suruki Employee of: UCB Pharma, Jeffrey Stark Employee of: UCB Pharma, Huifeng Yun Grant/research support from: Bristol-Myers Squibb and Pfizer, Sarah Siegel: None declared, Lang Chen: None declared, Jeffrey Curtis Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Corona, Crescendo, Genentech, Janssen, Pfizer, Roche and UCB Pharma, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Corona, Crescendo, Genentech, Janssen, Pfizer, Roche and UCB Pharma

Intraoperative integration of structured light scanning for automatic tissue classification: a feasibility study

PURPOSE

Structured light scanning is a promising inexpensive and accurate intraoperative imaging modality. Integration of these scanners in surgical workflows has the potential to enable rapid registration and augment preoperative imaging, in a practical and timely manner in the operating theatre. Previously, we have demonstrated the intraoperative feasibility of such scanners to capture anatomical surface information with high accuracy. The purpose of this study was to investigate the feasibility of automatically characterizing anatomical tissues from textural and spatial information captured by such scanners using machine learning. Assisted or automatic identification of relevant components of a captured scan is essential for effective integration of the technology in surgical workflow.

METHODS

During a clinical study, 3D surface scans for seven total knee arthroplasty patients were collected, and textural and spatial features for cartilage, bone, and ligament tissue were collected and annotated. These features were used to train and evaluate machine learning models. As part of our preliminary preparation, three fresh-frozen knee cadaver specimens were also used where 3D surface scans with texture information were collected during different dissection stages. The resulting models were manually segmented to isolate texture information for muscles, tendon, cartilage, and bone. This information, and detailed labels from dissections, provided an in-depth, finely annotated dataset for building machine learning classifiers.

RESULTS

For characterizing bone, cartilage, and ligament in the intraoperative surface models, random forest and neural network-based models achieved an accuracy of close to 80%, whereas an accuracy of close to 90% was obtained when only characterizing bone and cartilage. Average accuracy of 76-82% was reached for cadaver data in two-, three-, and four-class tissue separation.

CONCLUSIONS

The results of this project demonstrate the feasibility of machine learning methods to accurately classify multiple types of anatomical tissue. The ability to automatically characterize tissues in intraoperatively collected surface models would streamline the surgical workflow of using structured light scanners-paving the way to applications such as 3D documentation of surgery in addition to rapid registration and augmentation of preoperative imaging.

Cost-of-illness studies in chronic ulcers: a systematic review

OBJECTIVE

To systematically review the published academic literature on the cost of chronic ulcers.

METHODS

A literature search was conducted in MEDLINE, EMBASE, HealthSTAR, Econlit and CINAHL up to 12 May 2016 to identify potential studies for review. Cost search terms were based on validated algorithms. Clinical search terms were based on recent Cochrane reviews of interventions for chronic ulcers. Titles and abstracts were screened by two reviewers to determine eligibility for full text review. Study characteristics were summarised. The quality of reporting was evaluated using a modified cost-of-illness checklist. Mean costs were adjusted and inflated to 2015 $US and presented for different durations and perspectives.

RESULTS

Of 2267 studies identified, 36 were eligible and included in the systematic review. Most studies presented results from the health-care public payer or hospital perspective. Many studies included hospital costs in the analysis and only reported total costs without presenting condition-specific attributable costs. The mean cost of chronic ulcers ranged from $1000 per year for patient out of pocket costs to $30,000 per episode from the health-care public payer perspective. Mean one year cost from a health-care public payer perspective was $44,200 for diabetic foot ulcer (DFU), $15,400 for pressure ulcer (PU) and $11,000 for leg ulcer (LU).

CONCLUSIONS

There was large variability in study methods, perspectives, cost components and jurisdictions, making interpretation of costs difficult. Nevertheless, it appears that the cost for the treatment of chronic ulcers is substantial and greater attention needs to be made for preventive measures.

Prediction of Patient-specific Acute Hypotensive Episodes in ICU Using Deep Models

Forecasting acute hypotensive episodes (AHE) in intensive care patients has been of recent interest to researchers in the healthcare domain. Advance warning of an impending AHE may give care providers additional information to help mitigate the negative clinical impact of a serious event such as an AHE or prompt a search for an evolving disease process. However, the currently accepted definition of AHE is restrictive does not account for inter-patient variability. In this paper, we propose a novel definition of an AHE based on patient-specific features of blood pressure recordings. Next, we utilize a deep learning-based method to predict the onset of an AHE from multiple physiological readings for different definitions of the prediction task including variable input and gap lengths. Using a cohort of 538 patients, our model was able to successfully predict the onset of an AHE with an accuracy and AUC score of 0.80 and 0.87 respectively. Compared to a baseline logistic regression model, our model outperforms the baseline in most of the definitions of the prediction task.

Gynostemma pentaphyllum saponins induce melanogenesis and activate cAMP/PKA and Wnt/β-catenin signaling pathways

BACKGROUND

Melanogenesis is a physiological process of melanin production in response to UV exposure, which is modulated through multi-signaling pathways including cAMP/PKA, Wnt/β-catenin and MAPK signaling cascades.

HYPOTHESIS/PURPOSE

The present study aims to investigate the molecular mechanism of hyperpigmentation induced by Gynostemma pentaphyllum saponins.

STUDY DESIGN/METHODS

In this study, we investigated the melanogenic effects of triterpenoid saponins of Gynostemma pentaphyllum (GpS), a medicinal plant. Two mouse melanogenic cell lines B16 and B16F10 were employed for the current study.

RESULTS

The results showed that non-toxic doses of GpS markedly increased melanin formation in both B16 and B16F10 cells. Western blot analysis showed that GpS treatment significantly up-regulated the expression levels of the key melanogenic proteins, including tyrosinase (TYR), microphthalmia-associated transcription factor (MITF), TRP-1 and TRP-2 in a dose-dependent manner. The phospho-CREB, which is the downstream target of PKA is also elevated upon GpS treatment. We further observed that H89, a PKA inhibitor, attenuated the GpS induced tyrosinase activity, melanin content, the expression of phospho-CREB. In addition to the cAMP/PKA signaling pathway, GpS treatment also up-regulated the β-catenin of the Wnt signaling pathway which is involved in the transcriptional activation of MITF in melanogensis. We further demonstrated that treatment with GpS markedly enhance mRNA expression of MITF, along with the downstream target molecules, TYR, TRP-1 and TRP-2. Knock-down MITF with siMITF inhibited the expression of MITF mRNA by 63%, and the melanin content was reduced 70% in the siMITF-transfected cells compared to untransfected or scramble siRNA control cells.

CONCLUSION

These findings demonstrated strong melanogenic activities of GpS, and the MITF is essential for the melanogenesis stimulated by GpS.

Predictive Modeling using Intensive Care Unit Data: Considerations for Data Pre-processing and Analysis

The vast quantities of data generated and collected in the Intensive Care Unit (ICU) have given rise to large retrospective datasets that are frequently used for observational studies. The temporal nature and fine granularity of much of the data collected in the ICU enable the pursuit of predictive modeling, an increasingly common topic in ICU literature. Since patient conditions can rapidly change in the ICU, predicting the onset of events that are indicative of deteriorating patient state has potential clinical utility. However, the development of predictive modeling applications using ICU data requires a number of considerations to maximize prospective performance and clinical utility. In this study, we discuss the challenges encountered and considerations taken by using the prediction of acute hypotensive episodes as an example.