Cost Of Surveillance Research Articles

Impact of social determinants of health on hepatocellular carcinoma surveillance, treatment, and health care costs.

The impact of clinical factors and social determinants of health on treatment patterns and health care costs among patients with HCC is unknown. Using 100% Medicare Fee-For-Service claims and a commercial multipayor claims database, we identified patients diagnosed with HCC from January 1, 2017, to December 31, 2020. Surveillance receipt was defined 12 months prior to HCC diagnosis, whereas treatment and health care costs were assessed post-HCC diagnosis. Multinomial logistic regression was used to assess the association between demographics, social determinants of health, and surveillance or HCC treatment. Multivariable generalized linear regression was used to identify factors associated with total health care costs. Of the 32,239 patients with HCC (mean age 68 y, 67% male, 73% White), 70% received surveillance and only half (51%) received any treatment. Curative treatment receipt was higher among those with prior surveillance (24% with CT/MRI and 18% with ultrasound vs. 9% with no surveillance). Curative treatment was independently associated with HCC surveillance and inversely associated with Black race, lower education level, and diagnosis in the year 2020 (COVID-19 year). Higher health care costs were independently associated with Black race, low English proficiency, living alone, and diagnosis in 2018-2020, and inversely associated with CT/MRI-based surveillance. Race and social determinants of health were independently associated with curative treatment receipt and health care costs. Increasing access to high-quality HCC surveillance may improve treatment receipt and reduce health disparities among patients with HCC.

The Surveillance Strategy for Intraductal Pancreatic Mucinous Neoplasms: Criteria for Discontinuation.

To review the surveillance of IPMN, the risk of pancreatic cancer and the cost of surveillance. The increasing IPMN prevalence and low pancreatic cancer associated with IPMN question the necessity and cost-effectiveness of surveillance. Guidelines favour a 'watch and wait' approach, lacking clarity on stopping surveillance. This study aims to identify patients with pancreatic cancer risk equivalent to their age group, create guidelines for stopping surveillance and reduce NHS costs. Retrospective analysis of IPMN patients on surveillance in the WoS. Clinicopathological data were collected. Endpoints included pancreatic cancer development and surveillance pathway cost estimation. Age-matched controls were used for comparison using standardised incidence ratios (SIRs) for pancreatic cancer. Of 746 patients, 27 (3.62%) were resected. 3 (0.402%) developed pancreatic cancer and 44 (5.90%) developed worrisome features/ high-risk stigmata after a median surveillance of 48 (IQR 48) months. 221 (29.6%) had a stable cyst for at least 5 years and their SIR was 1.56 (95% CI 0.04-8.71). Patients ≥75 years with stable cysts for ≥5 years, SIR was 1.71 (95% CI 0.03-3.42). Patients ≥65 years with stable cysts of <15mm for ≥5 years and patients with stable cysts of <10mm for ≥5 years, had SIRs of 0. The cost of surveillance was £6,330.36 ($8,105.65) per resected patient and £2,032.78 ($2,602.85) per non-resected patient. Patients with stable IPMNs have similar pancreatic cancer risk as the general population. Surveillance discontinuation can be considered after 5 years in a cohort of patients, saving £106,211.19 ($136,020.42) per year.

Active surveillance for cardiac complications after major noncardiac surgery: implications on resource utilization and safety in high-risk patients

Abstract Background The 2022 ESC guidelines on cardiovascular assessment and management of patients undergoing noncardiac surgery recommend that high-risk patients should undergo active surveillance for cardiac complications, including perioperative myocardial infarction/injury (PMI), following major noncardiac surgery. Unfortunately, little is known about the resource use and safety of active surveillance compared to a control cohort (i.e. without active surveillance). Objective To quantify the impact of active surveillance for cardiac complications, by perioperative cardiac troponin (cTn) measurements and a systematic PMI work-up on working days, on resource usage and safety. Methods We did a retrospective comparison of non-randomised pre- vs post-implementation of an active surveillance program for cardiac complications in patients at elevated cardiovascular risk undergoing noncardiac surgery at two hospitals in Switzerland. The two cohorts' resource use and safety were compared. Resource use encompassed perioperative cTn measurements, ECGs, cardiac imaging, cardiology consultations as well as coronary angiography (CAG) and revascularisation procedures. Safety was assessed based on the number of "seemingly normal CAG" and complications arising from CAG and revascularisation procedures. Results A total of 13’147 patients, 10’346 in the active surveillance cohort and 2’805 in the standard-of-care (SOC) cohort, were eligible for this analysis. Patient characteristics between both cohorts were comparable (e.g. median age of 74 vs 73 and 44.8% vs 43% female, respectively). Patients in the active surveillance cohort underwent significantly more perioperative cTn measurements (86.4% vs 3.5%, respectively), postoperative ECGs (13.5% vs 5.7%), postoperative cardiac consultations (5.9% vs 2.4%), postoperative transthoracic echocardiogram (TTE) (7.5% vs 6.1%), postoperative myocardial perfusion imaging (MPI) (1.2% vs 0.6%), and postoperative CAG (0.8% vs 0.4%, all p &amp;lt;0.05). The increased resource use led to a substantial increase in detected cardiac complications within the first 48h after surgery: active surveillance 1’207 (12%) (95%CI 11%-12%) vs SOC 68 (2.4%) (95%CI 1.9%-3.1%). The active surveillance cohort generated an overall cardiac management cost of 236 Euros (95%CI 223–250) per patient vs 133 Euros (95%CI 110–160) per patient in the SOC cohort, resulting in an incremental cost for the active surveillance of 103 Euros (95%CI 110–160) per patient. Thereby the cost of detecting one additional cardiac complication within 48h was 989 Euros. Concerning safety, no significant differences in the number of "seemingly normal CAG" (6.4% vs 15%, p=0.1) and complications due to CAG and revascularisation (0.6% vs 5.1%, p=0.08) were observed. Conclusion The active surveillance for cardiac complications is safe when compared to a standard-of-care cohort while 989 Euros per additional detected cardiac complication seems reasonably priced.Resource-utilization tableOverview

Bird Leg Skin Lesions and Urbanization in a Neotropical Savanna City.

Urban sprawl threatens biodiversity and is responsible for significant changes in the species that live in these environments. Given the high cost of comprehensive surveillance, monitoring disease indirectly, such as detecting skin lesions in birds, may help us better understand the prevalence of diseases affecting wild populations. We assessed the frequency of leg skin lesions, as a proxy of disease presence, in 1,565 individuals of 25 species, along the urban matrix of a large Neotropical city, Brasília, Federal District, Brazil. We tested the hypothesis that there is an increase in the frequency of skin lesions in birds due to urban intensification. We observed an increasing trend in some bird species between the frequency of occurrence of lesions and the intensity of urbanization. Species with a higher number of captures had an increase in the percentage of lesions, indicating that the occurrence of lesions may be linked to higher population density or that detection of the effect occurs only when sample sizes are high and controlled among urbanization categories. Our study highlights how the intensity of urbanization may increase the risk of disease transmission for these species. Unfortunately, studies on this topic are scarce in Neotropical regions, despite the region's high biodiversity and urban expansion.

Hepatocellular carcinoma risk scores for non-viral liver disease: A systematic review and meta-analysis

BackgroundHepatocellular carcinoma (HCC) risk prediction models may provide a more personalised approach to surveillance for HCC among patients with cirrhosis. This systematic review aims to summarise the performance of HCC prediction models in patients with non-viral chronic liver disease. MethodThe study was prospectively registered with PROSPERO (ID: CRD42022370078) and reported in accordance with PRISMA guidelines. MEDLINE and EMBASE databases were searched using a validated search filter for prediction model studies. Two reviewers independently assessed studies for inclusion and risk of bias. Model performance (discrimination and calibration) were identified to assess the risk of HCC at specified time points. A random effects meta-analysis was done on a subset of studies that reported performance of the same model. Results7,854 studies were identified. After review, 14 studies with a total of 94,014 participants were included. 45% of patients had viral hepatitis, 27% alcohol related liver disease (ArLD) and 19% metabolic associated steatotic liver disease (MASLD). Follow-up ranged from 15.1 - 138 months. Only one model was developed using a competing risk approach. Age (7 models) and sex (6 models) were the most frequently included predictors. Model discrimination (AUROC or c-statistic) ranged from 0.61 - 0.947. Only the ‘aMAP’ score (age, male sex, albumin,bilirubin, and platelets) had sufficient external validation for quantitative analysis, with a pooled c-statistic of 0.81 (95% CI 0.80-0.83). Calibration was reported in only 9 of 14 studies. All studies were rated high risk of bias. ConclusionStudies describing risk prediction of HCC in non-viral chronic liver disease are poorly reported, have a high risk of bias and do not account for competing risk events. Patients with ArLD and MASLD are underrepresented in development and validation cohorts. These factors remain barriers to the clinical utility and uptake of HCC risk models in persons with the commonest liver diseases. Impact and implicationsThe recent EASL policy statement emphasises the potential of risk-based surveillance to reduce both HCC-related deaths and surveillance costs. This study addresses the gap in understanding the performance of current HCC risk models in patients with non-viral liver diseases, reflecting the epidemiological landscape of liver disease in Western countries.In our review of these models, we identified several key concerns regarding reporting standards and risk of bias and confirmed that patients with alcohol-related liver disease (ArLD) and metabolic-associated steatotic liver disease (MASLD) are underrepresented in model development and validation cohorts. Additionally, most models fail to account for the significant risk of competing events, leading to potential overestimation of true HCC risk.This study highlights these critical issues that may hinder the implementation of risk models in clinical practice and offers key recommendations for future model development studies.

Human-connected wild lands: How network analysis can inform invasive species management

Wild landscapes are critical strongholds for biodiversity, yet even in the remotest parts of the globe, increasing human use and development are leading to an influx of biodiversity threats including invasive species. Natural resource management agencies, and those that rely on public lands, need a better understanding of the long-distance dispersal pathways in which invasive species are introduced to remote locations. Pathway information is essential for targeting prevention and early detection across vast landscapes, but it is often challenged by information gaps and high surveillance costs. Data-driven approaches centered around a participating public can help resource managers and biosecurity professionals to better prioritize prevention and early detection activities to minimize incipient and secondary invasions. This study employed surveys with resource users to integrate and analyze multiple human-mediated dispersal networks for aquatic invasive species (AIS) across Alaska's part of the North American Boreal Forest. Specifically, it applied network analysis to further inform management priorities that so far were only based on a single pathway and different metrics. Results underline the vulnerability of remote wild freshwater systems to the introduction of AIS and provide a waterbody-specific tool for prioritizing monitoring and inform pathway-specific interventions that were unavailable through past research. The study compares the prioritization of waterbodies under newly derived network topology metrics accounting for multiple generic pathways with the existing single- species and single-pathway prediction model. Advantages of a more comprehensive multi-pathway network topology are discussed in the context of various invasion stages, multiple invasive taxa, and resource constraint conservation management systems.

Antibiotic use patterns and trends in the FDMN population and rural Bangladeshi population: a cross-sectional study

Global antibiotic resistance is a pressing issue, especially in Bangladesh, due to its widespread use, poor surveillance, and high treatment costs. This study compared antibiotic use between Rohingya and rural Bangladeshi residents, aiming to predict the frequency and tendency of commonly used antibiotics across different community levels. This was a cross-sectional descriptive study using a questionnaire. It involved Cox's Bazar camp, Tangail, and Bogura rural areas. Most participants were male, with 46.8% graduates and 20.8% untrained from mixed economic backgrounds. The study revealed that 62% adhered to doctors' orders, 28.5% followed pharmacists' recommendations, 6% sourced antibiotics from various places, 3% self-medicated, and 1% relied on advice from friends or relatives. Alarmingly, 25.3% did not complete their antibiotic courses. Age, region, advisor status, and education level were correlated with antibiotic use (P&lt;0.05), whereas socioeconomic status was not. The most commonly used medications among both rural and FDMN populations were azithromycin, ciprofloxacin, amoxicillin, and metronidazole. These findings highlight gaps in antibiotic use and adherence, with many not completing their treatments. Despite educational and economic variations, there is a general lack of concern about AMR, emphasizing the need for better awareness of and adherence to guidelines. Asian J. Med. Biol. Res. 2024, 10(3), 122-130

Value for money of medicine sampling and quality testing: evidence from Indonesia

BackgroundSubstandard and falsified medicines (SFMs) are a public health concern of global importance. Postmarket surveillance in the form of medicine sampling and quality testing can prevent and detect SFM, however,...

Impact of a machine learning–based prediction model on annual surveillance endoscopy costs for detecting gastric cancer

Background and AimsIn this study, we assessed our machine learning (ML)-based model's impact on reducing annual surveillance endoscopy costs for detecting gastric cancer (GC). MethodsAnalyzing 1099 patients with chronic gastritis undergoing annual esophagogastroduodenoscopy (EGD), we randomly divided them into training and test sets (4:1). Using gradient boosting decision trees and incorporating patient characteristics, the ML model was developed. In the test sets, we compared the EGD number needed to screen (NNS) one GC, the cost, and the GC detection rate across different risk stratification strategies. ResultsThe ML-selected high-risk cohort demonstrated low NNS values, low total cost, low cost per one GC, and high GC detection rates compared to alternative risk stratification approaches including operative link for gastric atrophy assessment, and operative link for gastric intestinal metaplasia assessment. ConclusionOur ML model holds promise in reducing endoscopy surveillance costs while maintaining a robust gastric cancer detection rate.

The Silent Threat: Unraveling the Impact of Rabies in Herbivores in Brazil.

Rabies, a zoonotic viral disease, poses a significant threat due to its adaptability to diverse environments. Herbivore rabies, predominantly affecting cattle, horses, and goats in Brazil, remains a concern, results in substantial losses in the livestock industry, and poses risks to public health. Rabies virus transmission, primarily through hematophagous bats in Latin America, underscores the need for effective strategies, and vaccination plays a crucial role in controlling herbivorous rabies, with systematic vaccination beingly the primary method. Efforts to control rabies in herbivores include vaccination campaigns, public awareness programs, and the enhancement of surveillance systems. Despite these initiatives, rabies persists and imposes an economic burden and a significant health risk. Economic impacts include losses in the livestock industry, trade restrictions on livestock products, and financial burdens on governments and farmers owing to control measures. Despite the considerable costs of campaigns, surveillance, and control, investing in rabies vaccination and control not only safeguards livestock, but also preserves public health, reduces human cases, and strengthens the sustainability of the livestock industry. Mitigating the impact of herbivorous rabies in Brazil requires integrated approaches and continuous investments in vaccination, surveillance, and control measures to protect public health and ensure the sustainability of the livestock industry, thus contributing to food and economic security.

Active surveillance versus immediate surgery in the management of low-risk papillary thyroid microcarcinoma: comparison of long-term costs in Brazil.

To compare the long-term medical costs of active surveillance (AS), partial thyroidectomy (PT), and total thyroidectomy (TT) in patients with low-risk papillary thyroid microcarcinoma (PTMC) receiving care covered by the Brazilian Public Health System. After reviewing AS cohorts and our own data, we created a model of AS, PT, and TT flow care for low-risk PTMC over 10, 20, and 30 years. The medical costs included those associated with diagnosis, surgery, and follow-up. We considered that 13.3% of the patients on AS would require surgery after a mean of 21.3 months, 4% undergoing TT would develop permanent hypoparathyroidism, and 43% undergoing PT would develop hypothyroidism. The most economical alternative was AS. The costs of TT per patient were higher than those of AS by 182.8% over 10 years (866.89 versus 306.49 US dollars [USD], respectively), by 152.9% over 20 years (1,023.66 versus 404.73 USD, respectively), and by 134.7% over 30 years (1,180.42 versus 502.96 USD, respectively). The costs of PT per patient were higher than those of AS by 16.0% over 10 years (355.66 versus 306.49 USD, respectively), by 16.9% over 20 years (473.41 versus 404.73 USD, respectively), and by 17.5% over 30 years (591.17 versus 502.96 USD, respectively). The AS approach was less costly than immediate surgery throughout 30 years of follow-up. Hence, the implementation of AS in Brazil should not be hindered by cost considerations.

Web‐based application to guide sampling on salmon farms for more precise estimation of sea louse abundance

AbstractObjectiveEfficiently managing sea lice on salmon farms through active surveillance, crucial for lice abundance estimation, is challenging due to the need for effective sampling schemes. To address this, we developed an application that considers infestation levels, farm structure, and management protocols, enhancing the precision of sampling strategies for sea louse abundance estimation.MethodsSimulation‐based methods are valuable for estimating suitable sample sizes in complex studies where standard formulae are inadequate. We introduce FishSampling, an open Web‐based application tailored to determine precise sample sizes for specific scenarios and objectives.ResultThe model incorporates factors such as sea lice abundance, farm pen numbers, potential clustering effects among these pens, and the desired confidence level. Simulation outcomes within this application provide practical advice on how to decide on the number of fish and pens to sample, under varying levels of assumed clustering.ConclusionThis approach can be used across the salmon aquaculture sector to improve sampling strategies for sea lice abundance estimation and balance surveillance costs against health objectives.

Healthcare and Epidemiological Surveillance Costs of Hepatitis A Outbreaks in Spain in Regions with and without Universal Hepatitis A Vaccination of Children during 2010-2018.

The aim of this study was to evaluate and compare hepatitis A outbreak-associated healthcare and epidemiological surveillance costs in Spain in two types of autonomous regions during 2010-2018: (1) regions with a prevention strategy based on universal hepatitis A vaccination of children and vaccination of high-risk population groups (Catalonia) and (2) regions with a prevention strategy based on vaccinating high-risk population groups (Castile and Leon, Murcia, Navarra, Community of Madrid, Community of Valencia). Healthcare costs were determined based on the resources used to treat hepatitis A outbreak-associated cases and hospitalizations. Epidemiological surveillance costs were calculated from the resources used during surveillance activities. The ratios for total, healthcare and epidemiological surveillance costs (regions without universal hepatitis A vaccination of children vs. Catalonia) were used to compare the two hepatitis A prevention strategies. From 2010 to 2018, the total, healthcare and epidemiological surveillance costs per million population were 1.75 times (EUR 101,671 vs. EUR 58,032), 1.96 times (EUR 75,500 vs. EUR 38,516) and 1.34 times greater (EUR 26,171 vs. EUR 19,515) in regions without universal hepatitis A vaccination of children than in Catalonia, respectively. The ratios tended to increase over time during 2010-2018. In 2015-2018, total, healthcare and epidemiological surveillance costs per million population were 2.68 times (EUR 69,993 vs. EUR 26,158), 2.86 times (EUR 53,807 vs. EUR 18,825) and 2.21 times greater (EUR 16,186 vs. EUR 7333) in regions without universal hepatitis A vaccination of children than in Catalonia, respectively. These findings suggest that universal hepatitis A vaccination of children could reduce hepatitis A outbreak-associated costs.

Newborn Screening for Li-Fraumeni Syndrome: Patient Perspectives.

Li-Fraumeni syndrome (LFS) is an inherited cancer predisposition syndrome with an estimated prevalence of 1 in 3,000-5,000 individuals. LFS poses a significant cancer risk throughout the lifespan, with notable cancer susceptibility in childhood. Despite being predominantly inherited, up to 20% of cases arise de novo. Surveillance protocols facilitate the reduction of mortality and morbidity through early cancer detection. While newborn screening (NBS) has proven effective in identifying newborns with rare genetic conditions, even those occurring as rarely as 1 in 185,000, its potential for detecting inherited cancer predispositions remains largely unexplored. This survey-based study investigates perspectives toward NBS for LFS among individuals with and parents of children with LFS receiving care at single comprehensive cancer center in the U.S. All participants unanimously supported NBS for LFS (n = 24). Reasons included empowerment (83.3%), control (66.7%), and peace of mind (54.2%), albeit with concerns about anxiety (62.5%) and devastation (50%) related to receiving positive results. Participants endorsed NBS as beneficial for cancer detection and prevention (91.7%), research efforts (87.5%), and family planning (79.2%) but voiced apprehensions about the financial cost of cancer surveillance (62.5%), emotional burdens (62.5%), and insurance coverage and discrimination (54.2%). Approximately 83% of respondents believed that parental consent should be required to screen newborns for LFS. This study revealed strong support for NBS for LFS despite the recognition of various perceived benefits and risks. These findings underscore the complex interplay between clinical, psychosocial, and ethical factors in considering NBS for LFS from the perspective of the LFS community.

Budget Impact Analysis of Circulating Tumor DNA Testing for Colon Cancer in Commercial Health and Medicare Advantage Plans

In a randomized clinical trial, treatment guided by tumor-informed circulating tumor (ct)DNA testing reduced adjuvant chemotherapy use without compromising recurrence-free survival in patients with stage II colon cancer. The potential effects of adopting ctDNA testing into routine patient care is unknown. To compare the total cost of patient care scenarios with and without the adoption of ctDNA testing. This budget impact analysis was conducted from the perspectives of US commercial health and Medicare Advantage payers. A decision-analytical model was populated with age-specific incidence of colon cancer, use of adjuvant chemotherapy, and use of single-agent or multiagent regimens. Total cost was estimated with the costs of ctDNA testing, drug acquisition, administration, surveillance, and adverse events. The analysis was conducted from September 2023 to January 2024. The adoption of ctDNA testing. The incremental cost in the first year following the adoption of ctDNA testing, where testing will affect patient treatment and costs. In hypothetical plans with 1 million individuals covered, 35 commercial health plan members and 102 Medicare Advantage members aged 75 years and younger were eligible for ctDNA testing. In the base case with a 50% adoption rate, total cost savings were $221 684 (equivalent to $0.02 per member per month [PMPM]) for a commercial payer and $116 720 (equivalent to $0.01 PMPM) for a Medicare Advantage payer. Cost savings were robust to variations in assumptions of all parameters in the commercial population but sensitive to variations in assumptions of adjuvant chemotherapy use rates in the Medicare Advantage population. The number needed to test to avoid 1 patient receiving adjuvant chemotherapy was 4 in the commercial population and 10 in the Medicare Advantage population. The budget-neutral cost for ctDNA testing was $16 202 for a commercial payer and $5793 for a Medicare Advantage payer. Use of tumor-informed ctDNA testing to guide adjuvant chemotherapy in postsurgery patients with stage II colon cancer was projected to result in cost savings for both commercial and Medicare Advantage payers. Adoption of ctDNA testing is therefore advantageous from a budgetary perspective.

Diagnostic accuracy of serological and imaging tests used in surveillance for hepatocellular carcinoma in adults with cirrhosis: a systematic review protocol.

Liver cirrhosis is the largest risk factor for developing hepatocellular carcinoma (HCC), and surveillance is therefore recommended among this population. Current guidance recommends surveillance with ultrasound, with or without alpha-fetoprotein (AFP). This review is part of a larger project looking at benefits, harms and costs of surveillance for HCC in people with cirrhosis. It aims to synthesise the evidence on the diagnostic accuracy of imaging or biomarker tests, alone or in combination, to identify HCC in adults with liver cirrhosis in a surveillance programme. We will identify studies through a 2021 Cochrane review with similar eligibility criteria, and a database search of MEDLINE, Embase and the Cochrane Database of Systematic Reviews. We will include diagnostic test accuracy studies with adult cirrhosis patients of any aetiology. Studies must assess at least one of the following index tests: ultrasound (US), magnetic resonance imaging (MRI), computerised tomography (CT), alpha-fetoprotein (AFP), des-gamma-carboxyprothrombin (DCP), lens culinaris agglutinin-reactive fraction of AFP (AFP-L3), a genomic biomarker, or a diagnostic prediction model incorporating at least one of the above-mentioned tests. We will assess studies for risk of bias using QUADAS-2 and QUADAS-C. We will combine data using bivariate random effects meta-analyses. For tests evaluated across varying diagnostic thresholds, we will produce pooled estimates of sensitivity and specificity across the full range of numerical thresholds, where possible. Where sufficient studies compare two or more index tests, we will perform additional analyses to compare the accuracy of different tests. Where feasible, we will stratify all meta-analyses by tumour size and patient characteristics, including cirrhosis aetiology and liver disease severity. This review will synthesise evidence across the full range of possible surveillance tests, using advanced statistical methods to summarise accuracy across all thresholds and to compare the accuracy of different tests. CRD42022357163.

A validated in-house assay for HIV drug resistance mutation surveillance from dried blood spot specimens

Despite increasing scale-up of antiretroviral therapy (ART) coverage, challenges related to adherence and HIV drug resistance (HIVDR) remain. The high cost of HIVDR surveillance is a persistent challenge with implementation in resource-constrained settings. Dried blood spot (DBS) specimens have been demonstrated to be a feasible alternative to plasma or serum for HIVDR genotyping and are more suitable for lower resource settings. There is a need for affordable HIVDR genotyping assays which can amplify HIV-1 sequences from DBS specimens, particularly those with low viral loads, at a low cost. Here, we present an in-house assay capable of reliably amplifying HIV-1 protease and partial reverse transcriptase genes from DBS specimens, which covers the complete World Health Organization 2009 list of drug resistance mutations under surveillance. DBS specimens were prepared using whole blood spiked with HIV-1 at concentrations of 10,000, 5000, 1000, and 500 copies/mL (n=30 for each concentration). Specimens were tested in triplicate. A two-step approach was used consisting of cDNA synthesis followed by nested PCR. The limit of detection of the assay was calculated to be approximately 5000 (95% CI: 3200–10,700) copies/mL for the protease gene and 3600 (95% CI: 2200–10,000) copies/mL for reverse transcriptase. The assay was observed to be most sensitive with higher viral load specimens (97.8% [95% CI: 92.2–99.7]) for both protease and reverse transcriptase at 10,000 copies/mL with performance decreasing with the use of specimens with lower viral loads (46.7% [36.1–57.5] and 60.0% [49.1–70.2] at 500 copies/mL for protease and reverse transcriptase, respectively). Ultimately, this assay presents a promising opportunity for use in resource-constrained settings. Future work should involve validation under field conditions including sub-optimal storage conditions and preparation of DBS with fingerprick blood in order to accurately reflect real-world collection scenarios.

O104: The “At-Risk” Infrainguinal Bypass Graft: benefit of Duplex Ultrasound Surveillance and Institutional costs of failure

Abstract Introduction The “Achilles heel” of infrainguinal surgical revascularisation (IISR) is that of restenosis. Duplex Ultrasound Surveillance (DUS) is undertaken to identify restenosis to permit intervention to maintain graft patency. We report the impact of DUS on outcomes focusing on patient- and treatment-associated costs. Methods Consecutive patients undergoing IISR at our Institution were assessed (January 2017 - December 2020). Data on DUS (1-, 6- and 12-month scans) were collated. Primary outcomes were mortality and major limb amputations (MLA) at 2-years post IISR. Grafts were defined “at-risk” if radiological evidence of significant graft stenosis or occlusion, with or without symptoms, was identified. Post IISR graft-specific Institutional costs for all patients were quantified. Results 254 patients had IISR in the observed period (196 men, median age 70yrs). Of those, 194 (76%) entered DUS, and 109 (43%) completed it. In patients who completed DUS (vs incomplete vs none), mortality was 6.4%, (vs 26.5% vs 38% respectively; p &amp;lt;0.001) and MLA rates were 6.4% (vs 12% vs 30%, p=0.174 and p&amp;lt;0.001 respectively). Managing at-risk grafts led to additional 384 cross-sectional imaging requests, 284 outpatient reviews, 933 hospital admission days and 233 open and endovascular reinterventions with a total additional NHS cost of £ 1.348.518 in 2 years. Per-patient costs were £216 (per patient, per month) for the complete DUS group vs £348 in no DUS group. Conclusion The ongoing management of IISR is associated with significant costs. Enrolment in and completion of a DUS programme is associated with improved patient outcomes and a reduction in costs.

Direct healthcare costs of oral cancer: A retrospective study from a tertiary care center

The aim of this study was to retrospectively evaluate the direct costs of OSCC treatment and postsurgical surveillance in a tertiary hospital in northeast Italy.Sixty-three consecutive patients surgically treated for primitive OSCC at S. Orsola Hospital in Bologna (Italy) between January 2018 and January 2020 were analyzed. Billing records of the Emilia Romagna healthcare system and institutional costs were used to derive specific costs for the following clinical categories: operating theatre costs, intensive and ordinary hospitalization, radiotherapy, chemotherapy, postsurgical complications, visits, and examinations during the follow-up period. The study population comprised 17 OSCC patients classified at stage I, 14 at stage II, eight at stage III, and 24 at stage IV.The estimated mean total direct cost for OSCC treatment and postsurgical surveillance was €26 338.48 per patient (stage I: €10 733, stage II: €19 642.9, stage III: €30 361.4, stage IV: €39 957.2). An advanced diagnosis (stages III and IV), complex surgical procedure, and loco-regional recurrences resulted in variables that were significantly associated with a higher cost of OSCC treatment and postsurgical surveillance.Redirection of funds used for OSCC treatment to screening measures may be an effective strategy to improve overall health outcomes and optimize national health resources.

Statistical Tests for Proportion Difference in One-to-Two Matched Binary Diagnostic Data: Application to Environmental Testing of Salmonella in the United States

Pooled sample testing is an effective strategy to reduce the cost of disease surveillance in human and animal medicine. Testing pooled samples commonly produces matched observations with dichotomous responses in medical and epidemiological research. Although standard approaches exist for one-to-one paired binary data analyses, there is not much work on one-to-two or one-to-N matched binary data in the current statistical literature. The existing Miettinen’s test assumes that the multiple observations from the same matched set are mutually independent. In this paper, we propose exact and asymptotic tests for one-to-two matched binary data. Our methods are markedly different from the previous studies in that we do not rely on the mutual independence assumption. The emphasis on the interdependence of observations within a matched set is inherent and attractive in both human health and veterinary medicine. It can be applied to all kinds of diagnostic studies with a one-to-two matched data structure. Our methods can be generalized to the one-to-N matched case. We discuss applications of the proposed methods to the environmental testing of salmonella in the United States.