Social Determinants of Health and Incident Apparent Treatment-Resistant Hypertension Among White and Black US Adults: The REGARDS Study.

BACKGROUND: We examined the association of multilevel social determinants of health with incident apparent treatment-resistant hypertension (aTRH). METHODS AND RESULTS: We analyzed data from 2774 White and 2257 Black US adults from the REGARDS (Reasons for Geographic and Racial Differences in Stroke) study taking antihypertensive medication without aTRH at baseline to estimate the association of social determinants of health with incident aTRH. Selection of social determinants of health was guided by the Healthy People 2030 domains of education, economic stability, social context, neighborhood environment, and health care access. Blood pressure (BP) was measured during study visits, and antihypertensive medication classes were identified through a pill bottle review. Incident aTRH was defined as (1) systolic BP ≥140 mm Hg or diastolic BP ≥90 mm Hg, or systolic BP ≥130 mm Hg or diastolic BP ≥80 mm Hg for those with diabetes or chronic kidney disease while taking ≥3 classes of antihypertensive medication or (2) taking ≥4 classes of antihypertensive medication regardless of BP level, at the follow-up visit. Over a median 9.5 years of follow-up, 15.9% of White and 24.0% of Black adults developed aTRH. A percent of the excess aTRH risk among Black versus White adults was mediated by low education (14.2%), low income (16.0%), not seeing a friend or relative in the past month (8.1%), not having someone to care for them if ill or disabled (7.6%), lack of health insurance (10.6%), living in a disadvantaged neighborhood (18.0%), and living in states with poor public health infrastructure (6.0%). CONCLUSIONS: Part of the association between race and incident aTRH risk was mediated by social determinants of health.

Population-average mediation analysis for zero-inflated count outcomes.

Mediation analysis is an increasingly popular statistical method for explaining causal pathways to inform intervention. While methods have increased, there is still a dearth of robust mediation methods for count outcomes with excess zeroes. Current mediation methods addressing this issue are computationally intensive, biased, or challenging to interpret. To overcome these limitations, we propose a new mediation methodology for zero-inflated count outcomes using the marginalized zero-inflated Poisson (MZIP) model and the counterfactual approach to mediation. This novel work gives population-average mediation effects whose variance can be estimated rapidly via delta method. This methodology is extended to cases with exposure-mediator interactions. We apply this novel methodology to explore if diabetes diagnosis can explain BMI differences in healthcare utilization and test model performance via simulations comparing the proposed MZIP method to existing zero-inflated and Poisson methods. We find that our proposed method minimizes bias and computation time compared to alternative approaches while allowing for straight-forward interpretations.

Application of marginalized zero-inflated models when mediators have excess zeroes.

Mediation analysis has become increasingly popular over the last decade as researchers are interested in assessing mechanistic pathways for intervention. Although available methods have increased, there are still limited options for mediation analysis with zero-inflated count variables where the distribution of response has a "cluster" of data at the zero value (i.e. distribution of number of cigarettes smoked per day, where nonsmokers cluster at zero cigarettes). The currently available methods do not obtain unbiased population average effects of mediation effects. In this paper, we propose an extension of the counterfactual approach to mediation with direct and indirect effects to scenarios where the mediator is a count variable with excess zeroes by utilizing the Marginalized Zero-Inflated Poisson Model (MZIP) for the mediator model. We derive direct and indirect effects for continuous, binary, and count outcomes, as well as adapt to allow mediator-exposure interactions. Our proposed work allows straightforward calculation of direct and indirect effects for the overall population mean values of the mediator, for scenarios in which researchers are interested in generalizing direct and indirect effects to the population. We apply this novel methodology to an application observing how alcohol consumption may explain sex differences in cholesterol and assess model performance via a simulation study comparing the proposed MZIP mediator framework to existing methods for marginal mediator effects.

Greater socioenvironmental risk factors and higher chronic pain stage are associated with thinner bilateral temporal lobes.

INTRODUCTION: Previous research indicates ethnic/race group differences in pain and neurodegenerative diseases. Accounting for socioenvironmental factors reduces ethnic/race group differences in clinical and experimental pain. In the current study sample, we previously reported that in individuals with knee pain, ethnic/race group differences were observed in bilateral temporal lobe thickness, areas of the brain associated with risk for Alzheimer's disease, and related dementias. The purpose of the study was to determine if socioenvironmental factors reduce or account for previously observed ethnic/race group differences and explore if a combined effect of socioenvironmental risk and chronic pain severity on temporal lobe cortices is evident. METHODS: Consistent with the prior study, the sample was comprised of 147 adults (95 women, 52 men), 45-85 years of age, who self-identified as non-Hispanic Black (n = 72) and non-Hispanic White (n = 75), with knee pain with/at risk for osteoarthritis. Measures included demographics, health history, pain questionnaires, cognitive screening, body mass index, individual- and community-level socioenvironmental factors (education, income, household size, marital and insurance status, and area deprivation index), and brain imaging. We computed a summative socioenvironmental risk index. RESULTS: Regression analyses showed that with the inclusion of socioenvironmental factors, the model was significant (p < .001), and sociodemographic (ethnic/race) group differences were not significant (p = .118). Additionally, findings revealed an additive stress load pattern indicating thinner temporal lobe cortices with greater socioenvironmental risk and chronic pain severity (p = .048). IMPLICATIONS: Although individual socioenvironmental factors were not independent predictors, when collectively combined in models, ethnic/race group differences in bilateral temporal lobe structures were not replicated. Further, combined socioenvironmental risk factors and higher chronic pain severity were associated with thinner bilateral temporal lobes.

Impact on stable chest pain pathways of CT fractional flow reserve.

OBJECTIVES: To evaluate the impact of introducing CT fractional flow reserve (FFRCT) on stable chest pain pathways, concordance with National Institute for Health and Care Excellence (NICE) chest pain guidelines, resource usage and revascularisation of patients from a tertiary UK cardiac centre rapid access chest pain clinic (RACPC). METHODS: Single-centre before and after study comparing data from electronic records and Strategic Tracing Service of all RACPC patients attending between 1 July 2017 and 31 December 2017, and 1 August 2018 and 31 January 2019. RESULTS: Two hundred and sixty-eight and 287 patients (overall mean age 62 years, range 26-89 years, 48.3% male), were eligible for first-line CT coronary angiography (CTCA) pre-FFRCT and post-FFRCT, respectively. First-line CTCA use per NICE Guideline CG95 increased (50.6% pre-FFRCT vs 75.7% post-FFRCT, p<0.001). More patients reached pathway endpoint (revascularisation or assumed medical management) after one investigation (74.9% pre-FFRCT vs 84.9% post-FFRCT, p=0.005). There were fewer stress (22.8% pre-FFRCT vs 7.7% post-FFRCT, p<0.001) and rest (10.4% pre-FFRCT vs 4.2% post-FFRCT, p=0.007) myocardial perfusion scans and diagnostic-only angiograms (25.5% vs 13.7%, p<0.001). Despite fewer invasive procedures (29.3% pre-FFRCT vs 17.6% post-FFRCT, p=0.002), revascularisation rates remained similar (10.4% pre-FFRCT vs 8.8% post-FFRCT, p=0.561). Avoiding invasive investigations reduced inpatient admissions (39.0% pre-FFRCT vs 24.3% post-FFRCT, p<0.001). Time to revascularisation was unchanged (153.5 days pre-FFRCT vs 142.0 post-FFRCT, p=0.925). Unplanned hospital attendances, emergency admissions and adverse events were similar. CONCLUSIONS: FFRCT adoption was associated with greater compliance with NICE guidelines, reduced invasive diagnostic angiography, planned admissions and needing more than one test to reach a pathway endpoint.

Our experience in developing and operating the Airway Intervention Registry for Recurrent Respiratory Papillomatosis (AIR-RRP): national data collection [version 2; peer review: 2 approved].

Recurrent respiratory papillomatosis (RRP) is characterised by benign wart-like growths in the respiratory tract caused by the human papillomavirus (HPV). These warts vary in size and grow quickly, causing voice changes and airway obstruction. Whilst the condition is rare, RRP is more common and aggressive in children. There is currently no curative treatment for HPV, therefore RRP is managed by maintaining a safe airway and a serviceable voice by repeated surgery to remove the growths. A lack of specific diagnostic codes prevents reliable case ascertainment of RRP from routine administrative databases such as Hospital Episode Statistics. In 2017 a cross-sectional survey identified 918 RRP patients in the UK, half of whom had received surgical intervention for RRP in the previous 12 months with 16 different interventions. Randomised controlled trials for RRP interventions are difficult due to the rarity of the disease, variation in severity and progression and non-standard care across the NHS. Consequently, there is a lack of definitive efficacy and safety evidence. The only national guidance for RRP interventions is "Radiofrequency cold ablation for respiratory papillomatosis" (NICE IPG434, 2017) which recommended further data collection due to lack of evidence. However, due to the wide variation in RRP management across the NHS, clinical opinion favoured that any data collection should include a comparison of safety and efficacy of all RRP interventions in order to advise which improved patient outcomes and quality of life. To address lack of evidence, and inform the future care of RRP patients, we developed a registry and used it to collect real-world data from patients receiving treatment for RRP in NHS hospitals across the UK. The purpose of this paper is to share lessons learned from this national data collection exercise to inform future clinical registry development.

RAC1B function is essential for breast cancer stem cell maintenance and chemoresistance of breast tumor cells.

Breast cancer stem cells (BCSC) are presumed to be responsible for treatment resistance, tumor recurrence and metastasis of breast tumors. However, development of BCSC-targeting therapies has been held back by their heterogeneity and the lack of BCSC-selective molecular targets. Here, we demonstrate that RAC1B, the only known alternatively spliced variant of the small GTPase RAC1, is expressed in a subset of BCSCs in vivo and its function is required for the maintenance of BCSCs and their chemoresistance to doxorubicin. In human breast cancer cell line MCF7, RAC1B is required for BCSC plasticity and chemoresistance to doxorubicin in vitro and for tumor-initiating abilities in vivo. Unlike Rac1, Rac1b function is dispensable for normal mammary gland development and mammary epithelial stem cell (MaSC) activity. In contrast, loss of Rac1b function in a mouse model of breast cancer hampers the BCSC activity and increases their chemosensitivity to doxorubicin treatment. Collectively, our data suggest that RAC1B is a clinically relevant molecular target for the development of BCSC-targeting therapies that may improve the effectiveness of doxorubicin-mediated chemotherapy.

Variation in IL6ST cytokine family function and the potential of IL6 trans-signalling in ERα positive breast cancer cells.

High expression of the transmembrane receptor IL6ST (gp130) has been identified as a predictive biomarker of endocrine treatment response in ERα-positive breast cancers. To investigate its function further in this disease, this study evaluated the expression, function and signalling of IL6ST in ERα-positive breast cancer cell lines and investigated crosstalk between ERα and IL6ST. IL6ST was differentially expressed in ERα-positive breast cancer cell lines (low in MCF-7, high in ZR751 and T47D), while multiple soluble isoforms of IL6ST were identified. IL6ST is the common signal transducing receptor component for the IL6ST family of cytokines and the effects of seven IL6ST cytokines on these cell lines were studied. These cytokines caused differential growth and migration effects in these cell lines e.g. MCF-7 cells were growth-stimulated, while ZR751 cells were inhibited by IL6 and OSM.. Activation of the STAT and ERK pathways is associated with these responses. Evidence to support trans-signalling involved in cell growth and migration was obtained in both MCF-7 and ZR751 models. Interaction between cytokines and estrogen on ERα-positive cell lines growth were analysed. High expression of IL6ST (in ZR751) may lead to growth inhibition by interacting cytokines while lower expression (in MCF-7) appears associated with proliferation. High IL6ST expression is consistent with a more beneficial clinical outcome if cytokine action contributes to anti-estrogen action.

Infection after ureteroscopy for ureteric stones: analysis of 71 305 cases in the Hospital Episode Statistics database.

OBJECTIVES: To investigate the burden of infectious complications following ureteroscopy (URS) for ureteric stones on a national level in England using data from the Hospital Episodes Statistics (HES) data warehouse. MATERIALS AND METHODS: A retrospective cohort was identified and followed up in HES during the period April 2013 to March 2020 for all procedure codes relating to ureteroscopic stone treatment (M27.1, M27.2, M27.3). Treatment episodes relating to the first URS ('index ureteroscopy') for each patient were further analysed. All subsequent admissions within 30 days were also captured. The primary outcome was diagnosis of urinary tract infection (UTI; including all codes relating to a UTI/sepsis within the first 30 days of index URS). Secondary outcomes were critical care attendance, attendance at the accident and emergency department (A&E) within 30 days, and mortality. RESULTS: A total of 71 305 index ureteroscopies were eligible for analysis. The median age was 55 years, and 81% of procedures were elective and 45% were undertaken as day-cases. At the time of index URS, 16% of patients had diabetes, 0.5% had coexisting neurological disease and 40% had an existing stent/nephrostomy. Overall, 6.8% of the cohort (n = 4822) had a diagnosis of UTI within 30 days of index URS (3.9% immediately after surgery). A total of 339 patients (0.5%) required an unplanned stay in critical care during their index URS admission; 8833 patients (12%) attended A&E within 30 days. Overall mortality was 0.18% (60 in-hospital, 65 within 30 days); 40 deaths (0.056%) included infection as a contributing cause of death. CONCLUSION: We present the largest series evaluating infectious complications after ureteroscopic stone treatment. The procedure is safe, with low inpatient infective complication and critical care admission rates.

Prospective Assessment of the Diagnostic Accuracy of Multi-site Photoplethysmography Pulse Measurements for Diagnosis of Peripheral Artery Disease in Primary Care.

Peripheral arterial disease (PAD) is associated with cerebral and coronary artery disease. Symptomatic PAD affects about 5% of people over 55 years; many more have asymptomatic PAD. Early detection enables modification of arterial disease risk factors. Diagnostically, assessment of symptoms or signs can be unreliable; ankle brachial pressure index (ABPI) testing is time-consuming and few healthcare professionals are properly trained. This study assessed the diagnostic accuracy of multi-site photoplethysmography (MPPG), an alternative non-invasive test for PAD, in primary care. PAD patients identified from general practice registers were age- and sex-matched with controls. Participants were assessed using MPPG, ABPI and duplex ultrasound (DUS). Outcome measures were sensitivity and specificity of MPPG and ABPI (relative to DUS) and concordance. MPPG test results were available in 249 of 298 eligible participants from 16 practices between May 2015 and November 2016. DUS detected PAD in 101/249 (40.6%). MPPG sensitivity was 79.8% (95% confidence interval [CI] 69.9-87.6%), with specificity 71.9% (95% CI 63.7-79.2%). ABPI sensitivity was 80.2% (95% CI 70.8-87.6%), with specificity 88.6% (95% CI 82-93.5%). With comparable sensitivity to ABPI, MPPG is quick, automated and simpler to do than ABPI; it offers the potential for rapid and accessible PAD assessments in primary care.

Self-sustaining smouldering combustion for the treatment of industrial oily waste.

Significant onsite handling and offsite management costs are incurred by oilfield operators annually to properly manage hydrocarbon waste streams such as tank bottoms or other oily sludge or oil impacted soil generated during oil and gas production processes. The current study reports for the first-time technical results of a field trial on use of a smouldering combustion technology performed in an active oilfield. Two treatment batches with oily sludges, stabilized through blending with soil, resulted in permanent hydrocarbon removal (98-99.9% reduction) to create treated soil that met standards for reuse as clean backfill onsite. Emissions profile data collected pre- and post-thermal oxidizer indicated effective removal of volatile organic compounds, CO and SO2, but had increased NO and CO2 due to combustion of propane to affect the thermal oxidation. Regulatory, financial, environmental and safety considerations are discussed in context of future full-scale smouldering technology deployment. The technology has the potential to lower overall unit costs for management of hydrocarbon impacted waste and reduce waste sent to landfills, which can benefit more remote sites.

Toll-like receptor 2 orchestrates a tumor suppressor response in non-small cell lung cancer.

Targeting early-stage lung cancer is vital to improve survival. However, the mechanisms and components of the early tumor suppressor response in lung cancer are not well understood. In this report, we study the role of Toll-like receptor 2 (TLR2), a regulator of oncogene-induced senescence, which is a key tumor suppressor response in premalignancy. Using human lung cancer samples and genetically engineered mouse models, we show that TLR2 is active early in lung tumorigenesis, where it correlates with improved survival and clinical regression. Mechanistically, TLR2 impairs early lung cancer progression via activation of cell intrinsic cell cycle arrest pathways and the proinflammatory senescence-associated secretory phenotype (SASP). The SASP regulates non-cell autonomous anti-tumor responses, such as immune surveillance of premalignant cells, and we observe impaired myeloid cell recruitment to lung tumors after Tlr2 loss. Last, we show that administration of a TLR2 agonist reduces lung tumor growth, highlighting TLR2 as a possible therapeutic target.

FAK promotes stromal PD-L2 expression associated with poor survival in pancreatic cancer.

BACKGROUND: Pancreatic Cancer is one of the most lethal cancers, with less than 8% of patients surviving 5 years following diagnosis. The last 40 years have seen only small incremental improvements in treatment options, highlighting the continued need to better define the cellular and molecular pathways contributing to therapy response and patient prognosis. METHODS: We combined CRISPR, shRNA and flow cytometry with mechanistic experiments using a KrasG12Dp53R172H mouse model of pancreatic cancer and analysis of publicly available human PDAC transcriptomic datasets. RESULTS: Here, we identify that expression of the immune checkpoint, Programmed Death Ligand 2 (PD-L2), is associated with poor prognosis, tumour grade, clinical stage and molecular subtype in patients with Pancreatic Ductal Adenocarcinoma (PDAC). We further show that PD-L2 is predominantly expressed in the stroma and, using an orthotopic murine model of PDAC, identify cancer cell-intrinsic Focal Adhesion Kinase (FAK) signalling as a regulator of PD-L2 stromal expression. Mechanistically, we find that FAK regulates interleukin-6, which can act in concert with interleukin-4 secreted by CD4 T-cells to drive elevated expression of PD-L2 on tumour-associated macrophages, dendritic cells and endothelial cells. CONCLUSIONS: These findings identify further complex heterocellular signalling networks contributing to FAK-mediated immune suppression in pancreatic cancer.

Reproductive history differs by molecular subtypes of breast cancer among women aged ≤ 50 years in Scotland diagnosed 2009-2016: a cross-sectional study.

BACKGROUND: The aetiology of breast cancers diagnosed ≤ 50 years of age remains unclear. We aimed to compare reproductive risk factors between molecular subtypes of breast cancer, thereby suggesting possible aetiologic clues, using routinely collected cancer registry and maternity data in Scotland. METHODS: We conducted a cross-sectional study of 4108 women aged ≤ 50 years with primary breast cancer diagnosed between 2009 and 2016 linked to maternity data. Molecular subtypes of breast cancer were defined using immunohistochemistry (IHC) tumour markers, oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), and tumour grade. Age-adjusted polytomous logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association of number of births, age at first birth and time since last birth with IHC-defined breast cancer subtypes. Luminal A-like was the reference compared to luminal B-like (HER2-), luminal B-like (HER2+), HER2-overexpressed and triple-negative breast cancer (TNBC). RESULTS: Mean (SD) for number of births, age at first birth and time since last birth was 1.4 (1.2) births, 27.2 (6.1) years and 11.0 (6.8) years, respectively. Luminal A-like was the most common subtype (40%), while HER2-overexpressed and TNBC represented 5% and 15% of cases, respectively. Larger numbers of births were recorded among women with HER2-overexpressed and TNBC compared with luminal A-like tumours (> 3 vs 0 births, OR 1.87, 95%CI 1.18-2.96; OR 1.44, 95%CI 1.07-1.94, respectively). Women with their most recent birth > 10 years compared to < 2 years were less likely to have TNBC tumours compared to luminal A-like (OR 0.63, 95%CI 0.41-0.97). We found limited evidence for differences by subtype with age at first birth. CONCLUSION: Number of births and time since last birth differed by molecular subtypes of breast cancer among women aged ≤ 50 years. Analyses using linked routine electronic medical records by molecularly defined tumour pathology data can be used to investigate the aetiology and prognosis of cancer.

MYC sensitises cells to apoptosis by driving energetic demand.

The MYC oncogene is a potent driver of growth and proliferation but also sensitises cells to apoptosis, which limits its oncogenic potential. MYC induces several biosynthetic programmes and primary cells overexpressing MYC are highly sensitive to glutamine withdrawal suggesting that MYC-induced sensitisation to apoptosis may be due to imbalance of metabolic/energetic supply and demand. Here we show that MYC elevates global transcription and translation, even in the absence of glutamine, revealing metabolic demand without corresponding supply. Glutamine withdrawal from MRC-5 fibroblasts depletes key tricarboxylic acid (TCA) cycle metabolites and, in combination with MYC activation, leads to AMP accumulation and nucleotide catabolism indicative of energetic stress. Further analyses reveal that glutamine supports viability through TCA cycle energetics rather than asparagine biosynthesis and that TCA cycle inhibition confers tumour suppression on MYC-driven lymphoma in vivo. In summary, glutamine supports the viability of MYC-overexpressing cells through an energetic rather than a biosynthetic mechanism.

Patent foramen ovale closure: A prospective UK registry linked to hospital episode statistics.

AIMS: PFO closure is a percutaneous intervention, which aims to reduce risk of recurrent stroke by preventing paradoxical embolism. The objective of this study was to measure procedural safety and longer-term effectiveness of PFO closure in a UK setting. METHODS AND RESULTS: Prospective registry data from patients with cryptogenic stroke eligible for PFO closure were collected for up to 2 years and linked to routine data sources for additional follow-up. Outcomes of interest included procedural success rate, health related quality of life, and longer-term death and neurological event rates. A total of 973 PFO closure procedures in 971 patients were included in analysis. Successful device implantation was achieved in 99.4 [95% CI 98.6 to 99.8]% of procedures, with one in-hospital death. During median follow-up of 758 (Q1:Q3 527:968) days, 33 patients experienced a subsequent neurological event, 76% of which were ischaemic in origin. Neurological event rate was 2.7 [95%CI 1.6 to 3.9]% at 1-year (n = 751) and 4.1 [95% CI 2.6 to 5.5]% at 2-years (n = 463) using Kaplan-Meier analysis. Improvements in patient quality of life (utility and visual analogue scale) were observed at 6-weeks and 6-months follow-up. CONCLUSION: Our observational study demonstrates that PFO closure for prevention of recurrent stroke is a relatively safe procedure but in routine clinical practice is associated with a slightly higher risk of recurrent neurological events than in randomised trials. We hypothesize that our study enrolled unselected patients with higher baseline risk, who were excluded from randomised trials, but who may benefit from a similar relative reduction in risk from the intervention.

Dietary Inflammatory Index (DII) is Associated with Movement-Evoked Pain Severity in Adults with Chronic Low Back Pain: Sociodemographic Differences.

Chronic low back pain (CLBP) is one of the leading causes of pain and disability in adults in the United States and disproportionately burdens non-Hispanic Black (NHB) individuals and females. Approximately 90% of CLBP cases are of unknown cause, and it is imperative that potential causes be explored. It has been reported that diet quality can influence pain state via diet-induced inflammation. The present study assessed the relationship between Dietary Inflammatory Index (DII) and movement evoked-pain severity in people with CLBP and investigated whether race/sex moderated the relationship between DII and movement-evoked pain. Results revealed no significant differences in DII scores between males and females, or between NHB and non-Hispanic White (NHW) participants. Participant sex significantly modified the relationship between DII and movement-evoked pain severity (P = .0155), such that movement-evoked pain severity was significantly impacted by DII scores in females, but not males. Participant race did not significantly moderate the DII - movement-evoked pain severity relationship. These results suggest that diet-induced inflammation may impact the CLBP experiences of females to a greater degree than males. Further research is needed to determine whether dietary interventions that reduce inflammation improve CLBP outcomes and whether these interventions may be differentially-beneficial based on sex. PERSPECTIVE: This article highlights the impact of diet-induced inflammation in a community-based sample as a whole, as well as stratified in various sociodemographic groups. This work expands our understanding of the influence of diet on pain experience and suggests that modifications to diet may be efficacious treatments for reducing chronic pain.

Validation of a Standardised Duplex Ultrasound Classification System for the Reporting and Grading of Peripheral Arterial Disease.

OBJECTIVE: Duplex ultrasound (DUS), a non-invasive means of arterial mapping, allows for the reliable diagnosis of peripheral arterial disease (PAD). One of the authors (C.P.O.), developed a standardised DUS based scoring system, devised for rapid detection and reporting of PAD. The purpose of this study was to validate this system, and to determine the diagnostic performance both overall and per disease severity. METHODS: In total, 250 participants were recruited, based on diagnosis of (n = 125) or absence of PAD (n = 125) from general practice registers. Right and left legs per subject were handled as independent readings, determining actual PAD status via ankle brachial pressure index (ABPI) < 0.9, and then further grading disease severity using suggested ABPI ranges. Data were excluded if no corresponding ABPI value was obtained per DUS determination or if the ABPI reading was > 1.4, owing to the risk of false negatives due to incompressible vessels. Diagnostic sensitivity and specificity were obtained overall, and per severity classification. Furthermore, inter-rater agreement between ABPI and DUS determined PAD severity was determined by linear weighted Cohen's kappa. RESULTS: The sensitivity and specificity in the detection of disease overall was 81.0% (95% confidence interval [CI] 73.4 - 87.2) and 86.3% (95% CI 82.3 - 89.8), respectively. From mild to severe PAD, sensitivity increased from 71.1% (95% CI 55.7 - 83.6) to 89.3% (95% CI 71.8 - 97.7). Furthermore, a Cohen's kappa value of 0.63 (95% CI 0.57 - 0.69) was obtained, indicating moderate agreement between the two diagnostic methods. CONCLUSION: The findings of this study validate the diagnostic performance of the standardised DUS scoring system, as well as its capacity to grade severity of disease, offering a potential tool for the identification of PAD in community/research settings following initial screening methods. Confirmatory work could include a comparison of DUS determined disease with gold standard methods of non-invasive angiography, and novel tools such as toe flex near infrared spectroscopy and multisite photoplethysmography.

Coblation intracapsular tonsillectomy: A cohort study of NHS practice in England using Hospital Episode Statistics.

OBJECTIVES: To identify paediatric intracapsular Coblation tonsillectomy procedures from routine administrative data in England, and determine their safety. DESIGN: Retrospective observational cohort study of four ENT centres using routine data from Hospital Episode Statistics (HES). SETTING: Acute NHS trusts in England conducting exclusively intracapsular Coblation tonsillectomy. PARTICIPANTS: Children (≤16 years old) undergoing bilateral intracapsular Coblation tonsillectomy. MAIN OUTCOME MEASURES: Number of procedures, readmissions for pain, readmissions for bleeding and requirement for additional surgery for regrowth. RESULTS: A total of 5525 procedures were identified. The median patient age was 4 (IQR 2-5). In-hospital complications occurred in 1%, with 0.1% returning to theatre for arrest of primary tonsil bleeding. Almost half of the procedures were conducted as a day-case (44%), with only a small proportion staying in hospital more than one night (7%). Within 28 days, 1.2% of patients were readmitted with bleeding, 0.7% with infection and 0.3% with pain; 0.2% of patients required return to theatre for control of secondary haemorrhage. Longitudinal follow-up has found that revision tonsil surgery is 0.3% at 1 year (n = 4498), 1.1% at 2 years (n = 2938), 1.7% at 3 years (n = 1781), 1.9% at 4 years (n = 905) and 2.2% at 5 years (n = 305). CONCLUSIONS: Intracapsular coblation tonsillectomy safety outcomes in this study show primary and secondary bleeding rates and emergency return to theatre rates are lower than all tonsillectomy techniques reported in the National Prospective Tonsillectomy Audit and also lower than previously published Hospital Episode Statistics analysis of tonsillectomy procedures.