Genomic attributes of airway commensal bacteria and mucosa

Microbial communities at the airway mucosal barrier are conserved and highly ordered, in likelihood reflecting co-evolution with human host factors. Freed of selection to digest nutrients, the airway microbiome underpins cognate management of mucosal immunity and pathogen resistance. We show here the initial results of systematic culture and whole-genome sequencing of the thoracic airway bacteria, identifying 52 novel species amongst 126 organisms that constitute 75% of commensals typically present in heathy individuals. Clinically relevant genes encode antimicrobial synthesis, adhesion and biofilm formation, immune modulation, iron utilisation, nitrous oxide (NO) metabolism and sphingolipid signalling. Using whole-genome content we identify dysbiotic features that may influence asthma and chronic obstructive pulmonary disease. We match isolate gene content to transcripts and metabolites expressed late in airway epithelial differentiation, identifying pathways to sustain host interactions with microbiota. Our results provide a systematic basis for decrypting interactions between commensals, pathogens, and mucosa in lung diseases of global significance.

Perceptions surrounding the possible interaction between physical activity, pollution and asthma in children and adolescents with and without asthma

A cornerstone of asthma management is maintaining physical activity (PA), but this may lead to increased exposure to, and deeper inhalation of, pollutants. Furthermore, children and adolescents may be more susceptible to the deleterious impacts of such exposures. Despite the recent air quality campaigns and media coverage surrounding the dangers of air pollution to respiratory health, few target children and their understanding of such issues.Using semi structured interviews, understanding of PA, air pollution and their interaction was explored with 25 youth aged 7-17 years. Utilising NVIVO 12 software, an atheoretical, inductive thematic analysis was conducted to identify key themes which were subsequently presented as pen profiles with the number of common responses within a theme indicative of its strength.The majority (88%) of youth's indicated traffic-related air pollution and global manufacturing as key sources of air pollution. Whilst all youths were aware of outdoor pollution, only 52% were aware of indoor air pollutants, of which 62% had asthma. Despite some uncertainty, all youths described pollution in a negative fashion, with 52% linking air pollution to undesirable effects on health, specifically respiratory health. PA in a polluted area was thought to be more dangerous than beneficial by 44%, although 24% suggested the benefits of PA would outweigh any detriment from pollution.Youth are aware of, and potentially compensate for, the interaction between air pollution and PA. Strategies are needed to allow youth to make more informed decisions regarding how to promote PA whilst minimising exposure to air pollution.

Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

INTRODUCTION

The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures.

METHODS

In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025.

FINDINGS

Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2-6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5-5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4-10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32-4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23-11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation.

INTERPRETATION

After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Heterogeneous Treatment Effects after Inspiratory Muscle Training during Recovery from Postacute COVID-19 Syndrome

PURPOSE

The objective of this study is to investigate whether heterogeneous treatment effects occur for changes in inspiratory muscle strength, perceived dyspnea, and health-related quality of life after 8 wk of unsupervised home-based inspiratory muscle training (IMT) in adults with postacute coronavirus disease 2019 (COVID-19) syndrome.

METHODS

In total, 147 adults with self-reported prior COVID-19 either completed an 8-wk home-based IMT intervention ( n = 111, 92 females, 48 ± 11 yr, 9.3 ± 3.6 months postacute COVID-19 infection) or acted as "usual care" wait list controls ( n = 36, 34 females, 49 ± 12 yr, 9.4 ± 3.2 months postacute COVID-19 infection).

RESULTS

Applying a Bayesian framework, we found clear evidence of heterogeneity of treatment response for inspiratory muscle strength: the estimated difference between standard deviations (SD) of the IMT and control groups was 22.8 cm H 2 O (75% credible interval (CrI), 4.7-37.7) for changes in maximal inspiratory pressure (MIP) and 86.8 pressure time units (75% CrI, 55.7-116.7) for sustained MIP (SMIP). Conversely, there were minimal differences in the SD between the IMT and the control group for changes in perceived dyspnea and health-related quality of life, providing no evidence of heterogeneous treatment effects. Higher cumulative power during the IMT intervention was related to changes in MIP ( β = 10.9 cm H 2 O (95% CrI, 5.3-16.8) per 1 SD) and SMIP ( β = 63.7 (32.2-95.3) pressure time units per 1 SD), clearly indicating an IMT dose response for changes in inspiratory muscle strength. Older age (>50 yr), a longer time postacute COVID-19 (>3 months), and greater severity of dyspnea at baseline were also associated with smaller improvements in inspiratory muscle strength.

CONCLUSIONS

Heterogeneous individual responses occurred after an 8-wk home-based IMT program in people with postacute COVID-19 syndrome. Consistent with standard exercise theory, larger improvements in inspiratory muscle strength are strongly related to a greater cumulative dose of IMT.

Estimating the contribution of respiratory pathogens to acute exacerbations of COPD using routine data

OBJECTIVES

To characterise microbiology testing and results associated with emergency admissions for acute exacerbation of COPD (AECOPD), and determine the accuracy of ICD-10 codes in retrospectively identifying laboratory-confirmed respiratory pathogens in this setting.

METHODS

Using person-level data from the Secure Anonymised Information Linkage Databank in Wales, we extracted emergency admissions for COPD from 1/12/2016 to 30/11/2018 and undertook linkage of admissions data to microbiology data to identify laboratory-confirmed infection. We further used these data to assess the accuracy of pathogen-specific ICD-10 codes.

RESULTS

We analysed data from 15,950 people who had 25,715 emergency admissions for COPD over the two-year period. 99.5% of admissions could be linked to a laboratory test within 7 days of admission date. Sputum was collected in 5,013 (19.5%) of admissions, and respiratory virus testing in 1,219 (4.7%). Where respiratory virus testing was undertaken, 46.7% returned any positive result. Influenza was the virus most frequently detected, in 21.5% of admissions where testing was conducted. ICD-10 codes exhibited low sensitivity in detecting laboratory-confirmed respiratory pathogens.

CONCLUSIONS

In people admitted to hospital with AECOPD, increased testing for respiratory viruses could enable more effective antibiotic stewardship and isolation of cases. Linkage with microbiology data achieves more accurate and reliable case definitions.

Incidence determinants and serological correlates of reactive symptoms following SARS-CoV-2 vaccination

Prospective population-based studies investigating associations between reactive symptoms following SARS-CoV-2 vaccination and serologic responses to vaccination are lacking. We therefore conducted a study in 9003 adults from the UK general population receiving SARS-CoV-2 vaccines as part of the national vaccination programme. Titres of combined IgG/IgA/IgM responses to SARS-CoV-2 spike (S) glycoprotein were determined in eluates of dried blood spots collected from all participants before and after vaccination. 4262 (47.3%) participants experienced systemic reactive symptoms after a first vaccine dose. Factors associating with lower risk of such symptoms included older age (aOR per additional 10 years of age 0.85, 95% CI: 0.81-0.90), male vs. female sex (0.59, 0.53-0.65) and receipt of an mRNA vaccine vs. ChAdOx1 nCoV-19 (0.29, 0.26-0.32 for BNT162b2; 0.06, 0.01-0.26 for mRNA-1273). Higher risk of such symptoms was associated with SARS-CoV-2 seropositivity and COVID-19 symptoms prior to vaccination (2.23, 1.78-2.81), but not with SARS-CoV-2 seropositivity in the absence of COVID-19 symptoms (0.94, 0.81-1.09). Presence vs. absence of self-reported anxiety or depression at enrolment associated with higher risk of such symptoms (1.24, 1.12-1.39). Post-vaccination anti-S titres were higher among participants who experienced reactive symptoms after vaccination vs. those who did not (P < 0.001). We conclude that factors influencing risk of systemic symptoms after SARS-CoV-2 vaccination include demographic characteristics, pre-vaccination SARS-CoV-2 serostatus and vaccine type. Participants experiencing reactive symptoms following SARS-CoV-2 vaccination had higher post-vaccination titres of IgG/A/M anti-S antibodies. Improved public understanding of the frequency of reactogenic symptoms and their positive association with vaccine immunogenicity could potentially increase vaccine uptake.

Defining clinical subtypes of adult asthma using electronic health records: Analysis of a large UK primary care database with external validation

INTRODUCTION

Asthma is one of the commonest chronic conditions in the world. Subtypes of asthma have been defined, typically from clinical datasets on small, well-characterised subpopulations of asthma patients. We sought to define asthma subtypes from large longitudinal primary care electronic health records (EHRs) using cluster analysis.

METHODS

In this retrospective cohort study, we extracted asthma subpopulations from the Optimum Patient Care Research Database (OPCRD) to robustly train and test algorithms, and externally validated findings in the Secure Anonymised Information Linkage (SAIL) Databank. In both databases, we identified adults with an asthma diagnosis code recorded in the three years prior to an index date. Train and test datasets were selected from OPCRD using an index date of Jan 1, 2016. Two internal validation datasets were selected from OPCRD using index dates of Jan 1, 2017 and 2018. Three external validation datasets were selected from SAIL using index dates of Jan 1, 2016, 2017 and 2018. Each dataset comprised 50,000 randomly selected non-overlapping patients. Subtypes were defined by applying multiple correspondence analysis and k-means cluster analysis to the train dataset, and were validated in the internal and external validation datasets.

RESULTS

We defined six asthma subtypes with clear clinical interpretability: low inhaled corticosteroid (ICS) use and low healthcare utilisation (30% of patients); low-to-medium ICS use (36%); low-to-medium ICS use and comorbidities (12%); varied ICS use and comorbid chronic obstructive pulmonary disease (4%); high (10%) and very high ICS use (7%). The subtypes were replicated with high accuracy in internal (91-92%) and external (84-86%) datasets.

CONCLUSION

Asthma subtypes derived and validated in large independent EHR databases were primarily defined by level of ICS use, level of healthcare use, and presence of comorbidities. This has important clinical implications towards defining asthma subtypes, facilitating patient stratification, and developing more personalised monitoring and treatment strategies.

SARS-CoV-2 infection risk among 77,587 healthcare workers: a national observational longitudinal cohort study in Wales, United Kingdom, April to November 2020

OBJECTIVES

To better understand the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among healthcare workers, leading to recommendations for the prioritisation of personal protective equipment, testing, training and vaccination.

DESIGN

Observational, longitudinal, national cohort study.

SETTING

Our cohort were secondary care (hospital-based) healthcare workers employed by NHS Wales (United Kingdom) organisations from 1 April 2020 to 30 November 2020.

PARTICIPANTS

We included 577,756 monthly observations among 77,587 healthcare workers. Using linked anonymised datasets, participants were grouped into 20 staff roles. Additionally, each role was deemed either patient-facing, non-patient-facing or undetermined. This was linked to individual demographic details and dates of positive SARS-CoV-2 PCR tests.

MAIN OUTCOME MEASURES

We used univariable and multivariable logistic regression models to determine odds ratios (ORs) for the risk of a positive SARS-CoV-2 PCR test.

RESULTS

Patient-facing healthcare workers were at the highest risk of SARS-CoV-2 infection with an adjusted OR (95% confidence interval [CI]) of 2.28 (95% CI 2.10-2.47). We found that after adjustment, foundation year doctors (OR 1.83 [95% CI 1.47-2.27]), healthcare support workers [OR 1.36 [95% CI 1.20-1.54]) and hospital nurses (OR 1.27 [95% CI 1.12-1.44]) were at the highest risk of infection among all staff groups. Younger healthcare workers and those living in more deprived areas were at a higher risk of infection. We also observed that infection rates varied over time and by organisation.

CONCLUSIONS

These findings have important policy implications for the prioritisation of vaccination, testing, training and personal protective equipment provision for patient-facing roles and the higher risk staff groups.

Perceptions of inspiratory muscle training in adults recovering from COVID-19

Post COVID-19 condition can occur following infection with SARS-CoV-2 and is characterised by persistent symptoms, including fatigue, breathlessness and cognitive dysfunction, impacting everyday functioning. This study explored how people living with post COVID-19 experienced an eight-week inspiratory muscle training (IMT) rehabilitation programme. Individualised semi-structured interviews with 33 adults (29 female; 49 ± 10 years; 6–11 months post-infection) explored expectations of IMT prior to the intervention, and post intervention interviews explored perceptions of IMT and its impact on recovery. Inductive thematic analysis was used to analyse the data. IMT helped many to feel proactive in managing their symptoms and was associated with perceived improvements in respiratory symptoms, exercise and work capacity, and daily functioning. IMT was well perceived and offers significant potential for use as part of a holistic recovery programme, although it is important to consider the complex, varied symptoms of post COVID-19, necessitating an individually tailored rehabilitation approach.

Risk factors for SARS-CoV-2 infection after primary vaccination with ChAdOx1 nCoV-19 or BNT162b2 and after booster vaccination with BNT162b2 or mRNA-1273: A population-based cohort study (COVIDENCE UK)

Background

Little is known about how demographic, behavioural, and vaccine-related factors affect risk of post-vaccination SARS-CoV-2 infection. We aimed to identify risk factors for SARS-CoV-2 infection after primary and booster vaccinations.

Methods

This prospective, population-based, UK study in adults (≥16 years) vaccinated against SARS-CoV-2 assessed risk of breakthrough SARS-CoV-2 infection up to February, 2022, for participants who completed a primary vaccination course (ChAdOx1 nCoV-19 or BNT162b2) and those who received a booster dose (BNT162b2 or mRNA-1273). Cox regression models explored associations between sociodemographic, behavioural, clinical, pharmacological, and nutritional factors and test-positive breakthrough infection, adjusted for local weekly SARS-CoV-2 incidence.

Findings

1051 (7·1%) of 14 713 post-primary participants and 1009 (9·5%) of 10 665 post-booster participants reported breakthrough infection, over a median follow-up of 203 days (IQR 195–216) and 85 days (66–103), respectively. Primary vaccination with ChAdOx1 (vs BNT162b2) was associated with higher risk of infection in both post-primary analysis (adjusted hazard ratio 1·63, 95% CI 1·41–1·88) and after an mRNA-1273 booster (1·26 [1·00–1·57] vs BNT162b2 primary and booster). Lower risk of infection was associated with older age (post-primary: 0·97 [0·96–0·97] per year; post-booster: 0·97 [0·97–0·98]), whereas higher risk of infection was associated with lower educational attainment (post-primary: 1·78 [1·44–2·20] for primary/secondary vs postgraduate; post-booster: 1·46 [1·16–1·83]) and at least three weekly visits to indoor public places (post-primary: 1·36 [1·13–1·63] vs none; post-booster: 1·29 [1·07–1·56]).

Interpretation

Vaccine type, socioeconomic status, age, and behaviours affect risk of breakthrough infection after primary and booster vaccinations.

Funding

Barts Charity, UK Research and Innovation Industrial Strategy Challenge Fund.

Determinants of Antibody Responses to SARS-CoV-2 Vaccines: Population-Based Longitudinal Study (COVIDENCE UK)

Antibody responses to SARS-CoV-2 vaccines vary for reasons that remain poorly understood. A range of sociodemographic, behavioural, clinical, pharmacologic and nutritional factors could explain these differences. To investigate this hypothesis, we tested for presence of combined IgG, IgA and IgM (IgGAM) anti-Spike antibodies before and after 2 doses of ChAdOx1 nCoV-19 (ChAdOx1, AstraZeneca) or BNT162b2 (Pfizer-BioNTech) in UK adults participating in a population-based longitudinal study who received their first dose of vaccine between December 2020 and July 2021. Information on sixty-six potential sociodemographic, behavioural, clinical, pharmacologic and nutritional determinants of serological response to vaccination was captured using serial online questionnaires. We used logistic regression to estimate multivariable-adjusted odds ratios (aORs) for associations between independent variables and risk of seronegativity following two vaccine doses. Additionally, percentage differences in antibody titres between groups were estimated in the sub-set of participants who were seropositive post-vaccination using linear regression. Anti-spike antibodies were undetectable in 378/9101 (4.2%) participants at a median of 8.6 weeks post second vaccine dose. Increased risk of post-vaccination seronegativity associated with administration of ChAdOx1 vs. BNT162b2 (adjusted odds ratio (aOR) 6.6, 95% CI 4.2−10.4), shorter interval between vaccine doses (aOR 1.6, 1.2−2.1, 6−10 vs. >10 weeks), poor vs. excellent general health (aOR 3.1, 1.4−7.0), immunodeficiency (aOR 6.5, 2.5−16.6) and immunosuppressant use (aOR 3.7, 2.4−5.7). Odds of seronegativity were lower for participants who were SARS-CoV-2 seropositive pre-vaccination (aOR 0.2, 0.0−0.6) and for those taking vitamin D supplements (aOR 0.7, 0.5−0.9). Serologic responses to vaccination did not associate with time of day of vaccine administration, lifestyle factors including tobacco smoking, alcohol intake and sleep, or use of anti-pyretics for management of reactive symptoms after vaccination. In a sub-set of 8727 individuals who were seropositive post-vaccination, lower antibody titres associated with administration of ChAdOx1 vs. BNT162b2 (43.4% lower, 41.8−44.8), longer duration between second vaccine dose and sampling (12.7% lower, 8.2−16.9, for 9−16 weeks vs. 2−4 weeks), shorter interval between vaccine doses (10.4% lower, 3.7−16.7, for <6 weeks vs. >10 weeks), receiving a second vaccine dose in October−December vs. April−June (47.7% lower, 11.4−69.1), older age (3.3% lower per 10-year increase in age, 2.1−4.6), and hypertension (4.1% lower, 1.1−6.9). Higher antibody titres associated with South Asian ethnicity (16.2% higher, 3.0−31.1, vs. White ethnicity) or Mixed/Multiple/Other ethnicity (11.8% higher, 2.9−21.6, vs. White ethnicity), higher body mass index (BMI; 2.9% higher, 0.2−5.7, for BMI 25−30 vs. <25 kg/m2) and pre-vaccination seropositivity for SARS-CoV-2 (105.1% higher, 94.1−116.6, for those seropositive and experienced COVID-19 symptoms vs. those who were seronegative pre-vaccination). In conclusion, we identify multiple determinants of antibody responses to SARS-CoV-2 vaccines, many of which are modifiable.

Effect of a test-and-treat approach to vitamin D supplementation on risk of all cause acute respiratory tract infection and covid-19: phase 3 randomised controlled trial (CORONAVIT)

OBJECTIVE

To determine the effect of population level implementation of a test-and-treat approach to correction of suboptimal vitamin D status (25-hydroxyvitamin D (25(OH)D) <75 nmol/L) on risk of all cause acute respiratory tract infection and covid 19.

DESIGN

Phase 3 open label randomised controlled trial.

SETTING

United Kingdom.

PARTICIPANTS

6200 people aged ≥16 years who were not taking vitamin D supplements at baseline.

INTERVENTIONS

Offer of a postal finger prick test of blood 25(OH)D concentration with provision of a six month supply of lower dose vitamin D (800 IU/day, n=1550) or higher dose vitamin D (3200 IU/day, n=1550) to those with blood 25(OH)D concentration <75 nmol/L, compared with no offer of testing or supplementation (n=3100). Follow-up was for six months.

MAIN OUTCOME MEASURES

The primary outcome was the proportion of participants with at least one swab test or doctor confirmed acute respiratory tract infection of any cause. A secondary outcome was the proportion of participants with swab test confirmed covid-19. Logistic regression was used to calculate odds ratios and associated 95% confidence intervals. The primary analysis was conducted by intention to treat.

RESULTS

Of 3100 participants offered a vitamin D test, 2958 (95.4%) accepted and 2674 (86.3%) had 25(OH)D concentrations <75 nmol/L and received vitamin D supplements (n=1328 lower dose, n=1346 higher dose). Compared with 136/2949 (4.6%) participants in the no offer group, at least one acute respiratory tract infection of any cause occurred in 87/1515 (5.7%) in the lower dose group (odds ratio 1.26, 95% confidence interval 0.96 to 1.66) and 76/1515 (5.0%) in the higher dose group (1.09, 0.82 to 1.46). Compared with 78/2949 (2.6%) participants in the no offer group, 55/1515 (3.6%) developed covid-19 in the lower dose group (1.39, 0.98 to 1.97) and 45/1515 (3.0%) in the higher dose group (1.13, 0.78 to 1.63).

CONCLUSIONS

Among people aged 16 years and older with a high baseline prevalence of suboptimal vitamin D status, implementation of a population level test-and-treat approach to vitamin D supplementation was not associated with a reduction in risk of all cause acute respiratory tract infection or covid-19.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04579640.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Inspiratory Muscle Training Enhances Recovery Post COVID-19: A Randomised Controlled Trial

Background

Many people recovering from coronavirus disease 2019 (COVID-19) experience prolonged symptoms, particularly breathlessness. We urgently need to identify safe and effective COVID-19 rehabilitative strategies. The aim of the current study was to investigate the potential rehabilitative role of inspiratory muscle training (IMT).

Methods

281 adults (age 46.6±12.2 years; 88% female) recovering from self-reported COVID-19 (9.0±4.2 months post-acute infection) were randomised 4:1 to an 8-week IMT or a “usual care” waitlist control arm. Health-related quality-of-life and breathlessness questionnaires (King's Brief Interstitial Lung Disease (K-BILD) and Transition Dyspnoea Index (TDI)), respiratory muscle strength, and fitness (Chester Step Test) were assessed pre- and post-intervention. The primary end-point was K-BILD total score, with the K-BILD domains and TDI being key secondary outcomes.

Results

According to intention to treat, there was no difference between groups in K-BILD total score post-intervention (control: 59.5±12.4; IMT: 58.2±12.3; p<0.05) but IMT elicited clinically meaningful improvements in the K-BILD domains for breathlessness (control: 59.8±12.6; IMT: 62.2±16.2; p<0.05) and chest symptoms (control: 59.2±18.7; IMT: 64.5±18.2; p<0.05), along with clinically meaningful improvements in breathlessness according to TDI (control: 0.9±1.7 versus 2.0±2.0; p<0.05). IMT also improved respiratory muscle strength and estimated aerobic fitness.

Conclusions

IMT may represent an important home-based rehabilitation strategy for wider implementation as part of COVID-19 rehabilitative strategies. Given the diverse nature of long COVID, further research is warranted on the individual responses to rehabilitation; the withdrawal rate herein highlights that no one strategy is likely to be appropriate for all.

IMT can significantly improve breathlessness and respiratory muscle function in people with long COVID, and represents an effective, home-based rehabilitation strategy that could be widely implemented as part of COVID-19 recovery strategieshttps://bit.ly/3HiEyz0

Determinants of pre-vaccination antibody responses to SARS-CoV-2: a population-based longitudinal study (COVIDENCE UK)

BACKGROUND

Prospective population-based studies investigating multiple determinants of pre-vaccination antibody responses to SARS-CoV-2 are lacking.

METHODS

We did a prospective population-based study in SARS-CoV-2 vaccine-naive UK adults recruited between May 1 and November 2, 2020, without a positive swab test result for SARS-CoV-2 prior to enrolment. Information on 88 potential sociodemographic, behavioural, nutritional, clinical and pharmacological risk factors was obtained through online questionnaires, and combined IgG/IgA/IgM responses to SARS-CoV-2 spike glycoprotein were determined in dried blood spots obtained between November 6, 2020, and April 18, 2021. We used logistic and linear regression to estimate adjusted odds ratios (aORs) and adjusted geometric mean ratios (aGMRs) for potential determinants of SARS-CoV-2 seropositivity (all participants) and antibody titres (seropositive participants only), respectively.

RESULTS

Of 11,130 participants, 1696 (15.2%) were seropositive. Factors independently associated with  higher risk of SARS-CoV-2 seropositivity included frontline health/care occupation (aOR 1.86, 95% CI 1.48-2.33), international travel (1.20, 1.07-1.35), number of visits to shops and other indoor public places (≥ 5 vs. 0/week: 1.29, 1.06-1.57, P-trend = 0.01), body mass index (BMI) ≥ 25 vs. < 25 kg/m² (1.24, 1.11-1.39), South Asian vs. White ethnicity (1.65, 1.10-2.49) and alcohol consumption ≥15 vs. 0 units/week (1.23, 1.04-1.46). Light physical exercise associated with  lower risk (0.80, 0.70-0.93, for ≥ 10 vs. 0-4 h/week). Among seropositive participants, higher titres of anti-Spike antibodies associated with factors including BMI ≥ 30 vs. < 25 kg/m² (aGMR 1.10, 1.02-1.19), South Asian vs. White ethnicity (1.22, 1.04-1.44), frontline health/care occupation (1.24, 95% CI 1.11-1.39), international travel (1.11, 1.05-1.16) and number of visits to shops and other indoor public places (≥ 5 vs. 0/week: 1.12, 1.02-1.23, P-trend = 0.01); these associations were not substantially attenuated by adjustment for COVID-19 disease severity.

CONCLUSIONS

Higher alcohol consumption and lower light physical exercise represent new modifiable risk factors for SARS-CoV-2 infection. Recognised associations between South Asian ethnic origin and obesity and higher risk of SARS-CoV-2 seropositivity were independent of other sociodemographic, behavioural, nutritional, clinical, and pharmacological factors investigated. Among seropositive participants, higher titres of anti-Spike antibodies in people of South Asian ancestry and in obese people were not explained by greater COVID-19 disease severity in these groups.

'I Live a Kind of Shadow Life': Individual Experiences of COVID-19 Recovery and the Impact on Physical Activity Levels

Understanding of strategies to support individuals recovering from coronavirus disease 2019 (COVID-19) is limited. ‘Long COVID’ is a multisystem disease characterised by a range of respiratory, gastrointestinal, cardiovascular, neurological, and musculoskeletal symptoms extending beyond 12 weeks. The aim of this study was to explore individuals’ experiences of recovering from COVID-19 to provide a better understanding of the acute and long-term impact of the disease on physical activity (PA). Individualised semi-structured interviews were conducted with 48 adults recovering from COVID-19 at 6–11 months post-infection. An inductive thematic analysis approach was used, reaching saturation at 14 interviews (10 female; 47 ± 7 years). Four overarching themes were identified: (i) Living with COVID-19, including managing activities of daily living; (ii) Dealing with the Unknown and self-management strategies; (iii) Re-introducing physical activity; and (iv) Challenges of returning to work. The return to PA, whether through activities of daily living, work or exercise, is often associated with the exacerbation of symptoms, presenting a range of challenges for individuals recovering from COVID-19. Individually tailored support is therefore required to address the unique challenges posed by COVID-19.

Impact of COVID-19 lockdown on emergency asthma admissions and deaths: national interrupted time series analyses for Scotland and Wales

BACKGROUND

The COVID-19 pandemic's impact on people with asthma is poorly understood. We hypothesised that lockdown restrictions were associated with reductions in severe asthma exacerbations requiring emergency asthma admissions and/or leading to death.

METHODS

Using data from Public Health Scotland and the Secure Anonymised Information Linkage Databank in Wales, we compared weekly counts of emergency admissions and deaths due to asthma over the first 18 weeks in 2020 with the national averages over 2015-2019. We modelled the impact of instigating lockdown on these outcomes using interrupted time-series analysis. Using fixed-effect meta-analysis, we derived pooled estimates of the overall changes in trends across the two nations. We also investigated trends in asthma-related primary care prescribing and emergency department (ED) attendances in Wales.

RESULTS

Lockdown was associated with a 36% pooled reduction in emergency admissions for asthma (incidence rate ratio, IRR: 0.64, 95% CI: 0.49 to 0.83, p value 0.001) across both countries. There was no significant change in asthma deaths (pooled IRR: 0.57, 95% CI: 0.17 to 1.94, p value 0.37). ED asthma attendances in Wales declined during lockdown (IRR: 0.85, 95% CI: 0.73 to 0.99, p value 0.03). A large spike of 121% more inhaled corticosteroids and 133% more oral corticosteroid prescriptions was seen in Wales in the week before lockdown.

CONCLUSIONS

National lockdowns were associated with substantial reductions in severe asthma exacerbations leading to hospital admission across both Scotland and Wales, with no corresponding increase in asthma deaths.

Identifying COPD in routinely collected electronic health records: a systematic scoping review

Although routinely collected electronic health records (EHRs) are widely used to examine outcomes related to COPD, consensus regarding the identification of cases from electronic healthcare databases is lacking. We systematically examine and summarise approaches from the recent literature. MEDLINE via EBSCOhost was searched for COPD-related studies using EHRs published from January 1, 2018 to November 30, 2019. Data were extracted relating to the case definition of COPD and determination of COPD severity and phenotypes. From 185 eligible studies, we found widespread variation in the definitions used to identify people with COPD in terms of code sets used (with 20 different code sets in use based on the ICD-10 classification alone) and requirement of additional criteria (relating to age (n=139), medication (n=31), multiplicity of events (n=21), spirometry (n=19) and smoking status (n=9)). Only seven studies used a case definition which had been validated against a reference standard in the same dataset. Various proxies of disease severity were used since spirometry results and patient-reported outcomes were not often available. To enable the research community to draw reliable insights from EHRs and aid comparability between studies, clear reporting and greater consistency of the definitions used to identify COPD and related outcome measures is key.

Effect of high-intensity interval training in adolescents with asthma: The eXercise for Asthma with Commando Joe's® (X4ACJ) trial

BACKGROUND

Higher levels of cardiorespiratory fitness are associated with reduced asthma severity and increased quality of life in those with asthma. Therefore, the purpose of this study was to evaluate the effectiveness of a 6-month high-intensity interval training (HIIT) intervention in adolescents with and without asthma.

METHODS

A total of 616 adolescents (334 boys; 13.0 ± 1.1 years, 1.57 ± 0.10 m, 52.6 ± 12.9 kg, mean ± SD), including 155 with asthma (78 boys), were recruited as part of a randomized controlled trial from 5 schools (4 control and 1 intervention). The 221 intervention participants (116 boys; 47 asthma) completed 6 months of school-based HIIT (30 min, 3 times per week, 10-30 s bouts at >90% age-predicted maximum heart rate with equal rest). At baseline, mid-intervention, post-intervention, and 3-month follow-up, measurements for 20-m shuttle run, body mass index (BMI), lung function, Pediatric Quality of Life Inventory, Paediatric Asthma Quality of Life Questionnaire, and Asthma Control Questionnaire were collected. Additionally, 69 adolescents (39 boys (of the 36 with asthma there were 21 boys)) also completed an incremental ramp test. For analysis, each group's data (intervention and control) were divided into those with and without asthma.

RESULTS

Participants with asthma did not differ from their peers in any parameter of aerobic fitness, at any time-point, but were characterized by a greater BMI. The intervention elicited a significant improvement in maximal aerobic fitness but no change in sub-maximal parameters of aerobic fitness, lung function, or quality of life irrespective of asthma status. Those in the intervention group maintained their BMI, whereas BMI significantly increased in the control group throughout the 6-month period.

CONCLUSION

HIIT represents an effective tool for improving aerobic fitness and maintaining BMI in adolescents, irrespective of asthma status. HIIT was well-tolerated by those with asthma, who evidenced a similar aerobic fitness to their healthy peers and responded equally well to a HIIT program.

Impact of COVID-19 lockdown on the incidence and mortality of acute exacerbations of chronic obstructive pulmonary disease: national interrupted time series analyses for Scotland and Wales

BACKGROUND

The COVID-19 pandemic and ensuing national lockdowns have dramatically changed the healthcare landscape. The pandemic's impact on people with chronic obstructive pulmonary disease (COPD) remains poorly understood. We hypothesised that the UK-wide lockdown restrictions were associated with reductions in severe COPD exacerbations. We provide the first national level analyses of the impact of the COVID-19 pandemic and first lockdown on severe COPD exacerbations resulting in emergency hospital admissions and/or leading to death as well as those recorded in primary care or emergency departments.

METHODS

Using data from Public Health Scotland and the Secure Anonymised Information Linkage Databank in Wales, we accessed weekly counts of emergency hospital admissions and deaths due to COPD over the first 30 weeks of 2020 and compared these to the national averages over the preceding 5 years. For both Scotland and Wales, we undertook interrupted time-series analyses to model the impact of instigating lockdown on these outcomes. Using fixed-effect meta-analysis, we derived pooled estimates of the overall changes in trends across the two nations.

RESULTS

Lockdown was associated with 48% pooled reduction in emergency admissions for COPD in both countries (incidence rate ratio, IRR 0.52, 95% CI 0.46 to 0.58), relative to the 5-year averages. There was no statistically significant change in deaths due to COPD (pooled IRR 1.08, 95% CI 0.87 to 1.33). In Wales, lockdown was associated with 39% reduction in primary care consultations for acute exacerbation of COPD (IRR 0.61, 95% CI 0.52 to 0.71) and 46% reduction in COPD-related emergency department attendances (IRR 0.54, 95% CI 0.36 to 0.81).

CONCLUSIONS

The UK-wide lockdown was associated with the most substantial reductions in COPD exacerbations ever seen across Scotland and Wales, with no corresponding increase in COPD deaths. This may have resulted from reduced transmission of respiratory infections, reduced exposure to outdoor air pollution and/or improved COPD self-management.

Association of socioeconomic deprivation with asthma care, outcomes, and deaths in Wales: A 5-year national linked primary and secondary care cohort study

BACKGROUND

Socioeconomic deprivation is known to be associated with worse outcomes in asthma, but there is a lack of population-based evidence of its impact across all stages of patient care. We investigated the association of socioeconomic deprivation with asthma-related care and outcomes across primary and secondary care and with asthma-related death in Wales.

METHODS AND FINDINGS

We constructed a national cohort, identified from 76% (2.4 million) of the Welsh population, of continuously treated asthma patients between 2013 and 2017 using anonymised, person-level, linked, routinely collected primary and secondary care data in the Secure Anonymised Information Linkage (SAIL) Databank. We investigated the association between asthma-related health service utilisation, prescribing, and deaths with the 2011 Welsh Index of Multiple Deprivation (WIMD) and its domains. We studied 106,926 patients (534,630 person-years), 56.3% were female, with mean age of 47.5 years (SD = 20.3). Compared to the least deprived patients, the most deprived patients had slightly fewer total asthma-related primary care consultations per patient (incidence rate ratio [IRR] = 0.98, 95% CI 0.97-0.99, p-value < 0.001), slightly fewer routine asthma reviews (IRR = 0.98, 0.97-0.99, p-value < 0.001), lower controller-to-total asthma medication ratios (AMRs; 0.50 versus 0.56, p-value < 0.001), more asthma-related accident and emergency (A&E) attendances (IRR = 1.27, 1.10-1.46, p-value = 0.001), more asthma emergency admissions (IRR = 1.56, 1.39-1.76, p-value < 0.001), longer asthma-related hospital stay (IRR = 1.64, 1.39-1.94, p-value < 0.001), and were at higher risk of asthma-related death (risk ratio of deaths with any mention of asthma 1.56, 1.18-2.07, p-value = 0.002). Study limitations include the deprivation index being area based and the potential for residual confounders and mediators.

CONCLUSIONS

In this study, we observed that the most deprived asthma patients in Wales had different prescribing patterns, more A&E attendances, more emergency hospital admissions, and substantially higher risk of death. Interventions specifically designed to improve treatment and outcomes for these disadvantaged groups are urgently needed.

Effect of High-Intensity Training and Asthma on the V˙O2 Kinetics of Adolescents

PURPOSE

High-intensity interval training (HIIT) represents a potent stimulus to the dynamic oxygen uptake (V˙O2) response in adults, but whether the same is evident in youth is unknown. HIIT has also been suggested to place a lower demand on the respiratory system, decreasing the likelihood of exacerbation in those with respiratory conditions, such as asthma.

METHODS

Sixty-nine adolescents (13.6 ± 0.9 yr; 36 asthma) took part, 35 of which (17 asthma) participated in a 30-min HIIT intervention three times a week for 6 months. Each participant completed an incremental ramp test to volitional exhaustion and three heavy-intensity constant work rate tests to determine the dynamic V˙O2, heart rate, and deoxyhemoglobin response at baseline, midintervention, postintervention and at a 3-month follow-up.

RESULTS

There was no influence of asthma at baseline or in response to the intervention. Participants in the intervention group demonstrated a faster V˙O2 time constant (τp) after intervention (intervention: 29.2 ± 5.7 s vs control: 34.2 ± 6.5 s; P = 0.003), with these differences maintained at follow-up (intervention: 32.5 ± 5.5 s vs control: 37.3 ± 8.7 s; P = 0.008). The intervention was associated with a speeding of the concentration of deoxyhemoglobin τ (pre: 20.1 ± 4.7 s vs post: 18.2 ± 4.1 s; P = 0.05) compared with a slowing over the same time period in the control participants (pre: 17.9 ± 4.9 s vs post: 20.1 ± 4.6 s; P = 0.012). Heart rate kinetics were not altered (pre: 46.5 ± 12.2 s vs post: 47.7 ± 11.1 s; P = 0.98).

CONCLUSION

These findings highlight the potential utility of school-based HIIT as a strategy to enhance the V˙O2 kinetics of youth, regardless of the presence of asthma.

Impact of air pollution on educational attainment for respiratory health treated students: A cross sectional data linkage study

INTRODUCTION

There is some evidence that exam results are worse when students are acutely exposed to air pollution. Studies investigating the association between air pollution and academic attainment have been constrained by small sample sizes.

METHODS

Cross sectional educational attainment data (2009-2015) from students aged 15-16 years in Cardiff, Wales were linked to primary health care data, modelled air pollution and measured pollen data, and analysed using multilevel linear regression models. Annual cohort, school and individual level confounders were adjusted for in single and multi-pollutant/pollen models. We stratified by treatment of asthma and/or Seasonal Allergic Rhinitis (SAR).

RESULTS

A unit (10μg/m3) increase of short-term exposure to NO2 was associated with 0.044 (95% CI: -0.079, -0.008) reduction of standardised Capped Point Score (CPS) after adjusting for individual and household risk factors for 18,241 students. This association remained statistically significant after controlling for other pollutants and pollen. There was no association of PM2.5, O3, or Pollen with standardised CPS remaining after adjustment. We found no evidence that treatment for asthma or SAR modified the observed NO2 effect on educational attainment.

CONCLUSION

Our study showed that short-term exposure to traffic-related air pollution, specifically NO2, was associated with detrimental educational attainment for students aged 15-16. Longitudinal investigations in different settings are required to confirm this possible impact and further work may uncover the long-term economic implications, and degree to which impacts are cumulative and permanent.

Asthma, body mass and aerobic fitness, the relationship in adolescents: The exercise for asthma with commando Joe's® (X4ACJ) trial

Although an association has been suggested between asthma, obesity, fitness and physical activity, the relationship between these parameters remains to be elucidated in adolescents. Six-hundred and sixteen adolescents were recruited (334 boys; 13.0 ± 1.1years; 1.57 ± 0.10m; 52.6 ± 12.9kg), of which 155 suffered from mild-to-moderate asthma (78 boys). Participants completed a 20-metre shuttle run test, lung function and 7-day objective physical activity measurements and completed asthma control and quality of life questionnaires. Furthermore, 69 adolescents (36 asthma; 21 boys) completed an incremental ramp cycle ergometer test. Although participants with asthma completed significantly fewer shuttle runs than their peers, peak V̇O₂ did not differ between the groups. However, adolescents with asthma engaged in less physical activity (53.9 ± 23.5 vs 60.5 ± 23.6minutes) and had higher BMI (22.2 ± 4.8 vs 20.4 ± 3.7kg·m-2), than their peers. Whilst a significant relationship was found between quality of life and cardiorespiratory fitness according to peak V̇O₂, only BMI was revealed as a significant predictor of asthma status. The current findings highlight the need to use accurate measures of cardiorespiratory fitness rather than indirect estimates to assess the influence of asthma during adolescence. Furthermore, the present study suggests that BMI and fitness may be key targets for future interventions seeking to improve asthma quality of life.

The illuminance of laryngoscopes at two central hospitals

Background: Direct laryngoscopy and successful endotracheal intubation require optimal illumination of laryngeal structures. The International Organization of Standardization (ISO) describes minimum adequate laryngoscope illuminance as 500 lux after 10 minutes, and further describes optimal dimensions of the illumination field. Laryngoscope light is subjectively assessed by the anaesthetist as part of theatre preparation. This study sought to describe the illumination of laryngoscopes at two academic hospitals, to compare illumination of incandescent and fibreoptic laryngoscopes and to compare the accuracy of a mobile phone application (app) to a lux meter. Methods: A prospective, contextual, descriptive study was conducted, testing the illumination of 43 laryngoscopes with a lux meter, as well as a mobile phone app. The illumination field size of each laryngoscope was determined. Results: ISO Standard for illumination was met by 8 (18.6%) laryngoscopes, and 11 (25.5%) had an adequate illumination field. Only 4 (9.3%) laryngoscopes met both criteria. The mobile phone app readings were significantly different from those obtained with a lux meter (p = 0.0008). After battery replacement 23 further laryngoscopes demonstrated an adequate illuminance. No significant difference was found between incandescent and fibreoptic laryngoscope illuminance (p = 0.86). Conclusion: This study demonstrated that the available laryngoscopes had poor illuminance. A mobile phone app was not comparable to a lux meter. Routine objective illuminance testing as well as regular battery changes are suggested to be implemented.

Effect of asthma and six-months high-intensity interval training on heart rate variability during exercise in adolescents

Little is known regarding the influence of asthma and exercise, and their interaction, on heart rate variability (HRV) in adolescents. Thirty-one adolescents with asthma (13.7±0.9 years; 21.9±3.9 kg·m^-2; 19 boys, 12 girls) and thirty-three healthy adolescents (13.8±0.9 years; 20.3±3.2 kg·m^-2; 16 boys, 17 girls) completed an incremental ramp test and three heavy-intensity constant-work-rate cycle tests. Thirteen adolescents (7 boys, 6 girls; 6 asthma, 7 control) completed six-months high-intensity interval training (HIIT) and were compared to age- and sex-matched controls. Standard time-domain, frequency-domain and non-linear indices of HRV were derived at baseline, three- and six-months. Asthma did not influence HRV at baseline or following HIIT. Total power, low frequency and normalised low frequency power, and sympathovagal balance increased at three-months in HIIT, subsequently declining towards baseline at six-months. Normalised high frequency power was reduced at three-months in both groups, which was sustained at six-months. No effects of HIIT were observed in the time-domain nor in the non-linear indices. HRV was not influenced by asthma, potentially because such derangements are a function of disease progression, severity or duration. HIIT may be associated with a short-term shift towards greater sympathetic predominance during exercise, perhaps caused by physiological overload and fatigue.

Creating individual level air pollution exposures in an anonymised data safe haven: a platform for evaluating impact on educational attainment

Introduction

There is a lack of evidence on the adverse effects of air pollution on cognition for people with air quality-related health conditions. We propose that educational attainment, as a proxy for cognition, may increase with improved air quality. This study will explore whether asthma and seasonal allergic rhinitis, when exacerbated by acute exposure to air pollution, is associated with educational attainment.

Objective

To describe the preparation of individual and household-level linked environmental and health data for analysis within an anonymised safe haven. Also to introduce our statistical analysis plan for our study: COgnition, Respiratory Tract illness and Effects of eXposure (CORTEX).

Methods

We imported daily air pollution and aeroallergen data, and individual level education data into the SAIL databank, an anonymised safe haven for person-based records. We linked individual-level education, socioeconomic and health data to air quality data for home and school locations, creating tailored exposures for individuals across a city. We developed daily exposure data for all pupils in repeated cross sectional exam cohorts (2009-2015).

Conclusion

We have used the SAIL databank, an innovative, data safe haven to create individual-level exposures to air pollution and pollen for multiple daily home and school locations. The analysis platform will allow us to evaluate retrospectively the impact of air quality on attainment for multiple cross-sectional cohorts of pupils. Our methods will allow us to distinguish between the pollution impacts on educational attainment for pupils with and without respiratory health conditions. The results from this study will further our understanding of the effects of air quality and respiratory-related health conditions on cognition.

Highlights

Identifying patients with asthma-chronic obstructive pulmonary disease overlap syndrome using latent class analysis of electronic health record data: a study protocol

Asthma and chronic obstructive pulmonary disease (COPD) are two common different clinical diagnoses with overlapping clinical features. Both conditions have been increasingly studied using electronic health records (EHR). Asthma-COPD overlap syndrome (ACOS) is an emerging concept where clinical features from both conditions co-exist, and for which, however, there is no consensus definition. Nonetheless, we expect EHR data of people with ACOS to be systematically different from those with "asthma only" or "COPD only". We aim to develop a latent class model to understand the overlap between asthma and COPD in EHR data. From the Secure Anonymised Information Linkage (SAIL) databank, we will use routinely collected primary care data recorded in or before 2014 in Wales for people who aged 40 years or more on 1st Jan 2014. Based on this latent class model, we will train a classification algorithm and compare its performance with commonly used objective and self-reported case definitions for asthma and COPD. The resulting classification algorithm is intended to be used to identify people with ACOS, 'asthma only', and 'COPD only' in primary care datasets.

Defining asthma and assessing asthma outcomes using electronic health record data: a systematic scoping review

There is currently no consensus on approaches to defining asthma or assessing asthma outcomes using electronic health record-derived data. We explored these approaches in the recent literature and examined the clarity of reporting.

We systematically searched for asthma-related articles published between January 1, 2014 and December 31, 2015, extracted the algorithms used to identify asthma patients and assess severity, control and exacerbations, and examined how the validity of these outcomes was justified.

From 113 eligible articles, we found significant heterogeneity in the algorithms used to define asthma (n=66 different algorithms), severity (n=18), control (n=9) and exacerbations (n=24). For the majority of algorithms (n=106), validity was not justified. In the remaining cases, approaches ranged from using algorithms validated in the same databases to using nonvalidated algorithms that were based on clinical judgement or clinical guidelines. The implementation of these algorithms was suboptimally described overall.

Although electronic health record-derived data are now widely used to study asthma, the approaches being used are significantly varied and are often underdescribed, rendering it difficult to assess the validity of studies and compare their findings. Given the substantial growth in this body of literature, it is crucial that scientific consensus is reached on the underlying definitions and algorithms.

Biomarkers in adult asthma: a systematic review of 8-isoprostane in exhaled breath condensate

OBJECTIVES

We aimed to assess the evidence for the use of 8-isoprostane in exhaled breath condensate (EBC) as a biomarker in adult asthma.

DESIGN

A systematic review and meta-analysis of EBC 8-isoprostane.

METHODS

We searched a number of online databases (including PubMed, Embase and Scopus) in January 2016. We included studies of adult non-smokers with EBC collection and asthma diagnosis conducted according to recognised guidelines. We aimed to pool data using random effects meta-analysis and assess heterogeneity using I ².

RESULTS

We included twenty studies, the findings from which were inconsistent. Seven studies (n = 329) reported 8-isoprostane levels in asthma to be significantly higher than that of control groups, whilst six studies (n = 403) did not. Only four studies were appropriate for inclusion in a random effects meta-analysis of mean difference. This found a statistically significant between-groups difference of 22 pg ml^-1. Confidence in the result is limited by the small number of studies and by substantial statistical heterogeneity (I ² = 94).

CONCLUSION

The clinical value of EBC 8-isoprostane as a quantitative assessment of oxidative stress in asthma remains unclear due to variability in results and methodological heterogeneity. It is essential to develop a robust and standardised methodology if the use of EBC 8-isoprostane in asthma is to be properly evaluated.

An epigenome-wide association study of total serum IgE in Hispanic children

BACKGROUND

Total IgE is a therapeutic target in patients with allergic diseases. DNA methylation in white blood cells (WBCs) was associated with total IgE levels in an epigenome-wide association study of white subjects. Whether DNA methylation of eosinophils explains these findings is insufficiently understood.

METHODS

We tested for association between genome-wide DNA methylation in WBCs and total IgE levels in 2 studies of Hispanic children: the Puerto Rico Genetics of Asthma and Lifestyle Study (PR-GOAL; n = 306) and the Genes-environments and Admixture in Latino Americans (GALA II) study (n = 573). Whole-genome methylation of DNA from WBCs was measured by using the Illumina Infinium HumanMethylation450 BeadChip. Total IgE levels were measured by using the UniCAP 100 system. In PR-GOAL WBC types (ie, neutrophils, eosinophils, basophils, lymphocytes, and monocytes) in peripheral blood were measured by using Coulter Counter techniques. In the GALA II study WBC types were imputed. Multivariable linear regression was used for the analysis of DNA methylation and total IgE levels, which was first conducted separately for each cohort, and then results from the 2 cohorts were combined in a meta-analysis.

RESULTS

CpG sites in multiple genes, including novel findings and results previously reported in white subjects, were significantly associated with total IgE levels. However, adjustment for WBC types resulted in markedly fewer significant sites. Top findings from this adjusted meta-analysis were in the genes ZFPM1 (P = 1.5 × 10^-12), ACOT7 (P = 2.5 × 10^-11), and MND1 (P = 1.4 × 10^-9).

CONCLUSIONS

In an epigenome-wide association study adjusted for WBC types (including eosinophils), methylation changes in genes enriched in pathways relevant to asthma and immune responses were associated with total IgE levels among Hispanic children.

An experimental evaluation of the Agility MLC for motion-compensated VMAT delivery

An algorithm for dynamic multileaf-collimator (dMLC) tracking of a target performing a known a priori, rigid-body motion during volumetric modulated arc therapy (VMAT), has been experimentally validated and applied to investigate the potential of the Agility (Elekta AB, Stockholm, Sweden) multileaf-collimator (MLC) for use in motion-compensated VMAT delivery. For five VMAT patients, dosimetric measurements were performed using the Delta(4) radiation detector (ScandiDos, Uppsala, Sweden) and the accuracy of dMLC tracking was evaluated using a gamma-analysis, with threshold levels of 3% for dose and 3 mm for distance-to-agreement. For a motion trajectory with components in two orthogonal directions, the mean gamma-analysis pass rate without tracking was found to be 58.0%, 59.0% and 60.9% and was increased to 89.1%, 88.3% and 93.1% with MLC tracking, for time periods of motion of 4 s, 6 s and 10 s respectively. Simulations were performed to compare the efficiency of the Agility MLC with the MLCi MLC when used for motion-compensated VMAT delivery for the same treatment plans and motion trajectories. Delivery time increases from a static-tumour to dMLC-tracking VMAT delivery were observed in the range 0%–20% for the Agility, and 0%–57% with the MLCi, indicating that the increased leaf speed of the Agility MLC is beneficial for MLC tracking during lung radiotherapy.

Interactive effect of STAT6 and IL13 gene polymorphisms on eczema status: results from a longitudinal and a cross-sectional study

BACKGROUND

Eczema is a prevalent skin disease that is mainly characterized by systemic deviation of immune response and defective epidermal barrier. Th2 cytokines, such as IL-13 and transcription factor STAT6 are key elements in the inflammatory response that characterize allergic disorders, including eczema. Previous genetic association studies showed inconsistent results for the association of single nucleotide polymorphisms (SNPs) with eczema. Our aim was to investigate whether SNPs in IL13 and STAT6 genes, which share a biological pathway, have an interactive effect on eczema risk.

METHODS

Data from two independent population-based studies were analyzed, namely the Isle of Wight birth cohort study (IOW; n = 1,456) and for the purpose of replication the Swansea PAPA (Poblogaeth Asthma Prifysgol Abertawe; n = 1,445) cross-sectional study. Log-binomial regressions were applied to (i) account for the interaction between IL13 (rs20541) and STAT6 (rs1059513) polymorphisms and (ii) estimate the combined effect, in terms of risk ratios (RRs), of both risk factors on the risk of eczema.

RESULTS

Under a dominant genetic model, the interaction term [IL13 (rs20541) × STAT6 (rs1059513)] was statistically significant in both studies (IOW: adjusted P(interaction) = 0.046; PAPA: P(interaction) = 0.037). The assessment of the combined effect associated with having risk genotypes in both SNPs yielded a 1.52-fold increased risk of eczema in the IOW study (95% confidence interval (CI): 1.05 - 2.20; P = 0.028) and a 2.01-fold higher risk of eczema (95% CI: 1.29 - 3.12; P = 0.002) in the PAPA study population.

CONCLUSIONS

Our study adds to the current knowledge of genetic susceptibility by demonstrating for the first time an interactive effect between SNPs in IL13 (rs20541) and STAT6 (rs1059513) on the occurrence of eczema in two independent samples. Findings of this report further support the emerging evidence that points toward the existence of genetic effects that occur via complex networks involving gene-gene interactions (epistasis).

Cohort profile: the housing regeneration and health study

A cohort comprising residents of a housing regeneration and health programme was created from routinely collected data using a system which allows us to anonymously link housing data to individuals and their health. The regeneration programme incorporating four rolling work packages runs from 2009 to 2014. The main intervention cohort we describe here contains the 18 312 residents of 9051 residences at baseline. The cohort will be followed continuously through routine health data (demographics, mortality, hospital admissions and general practitioner records including prescriptions) with periodic updates of housing regeneration intervention data. Here, we describe the baseline data for the primary health outcomes of emergency hospital admissions for cardiovascular and respiratory conditions and injuries for those aged ≥60 years. We will compare the health of residents within the homes before and after the housing regeneration work has taken place, and we will calculate the change in health service costs with use of hospital and General Practitioners (GP) services. We will also use a difference in differences approach to assess changes in comparison with comparator cohorts. These data will be accessible at the end of the study period in 2016. Further information about this study can be obtained from Ronan Lyons; r.a.lyons@swansea.ac.uk.

Fetal thoracoamniotic shunting for large macrocystic congenital cystic adenomatoid malformations of the lung

OBJECTIVE

To evaluate fetal thoracoamniotic shunting for isolated large macrocystic congenital cystic adenomatoid malformations (CCAM) of the lung.

METHODS

This was a retrospective study of 11 fetuses with macrocystic CCAM who underwent thoracoamniotic shunting. This procedure was offered if fetal hydrops or signs of evolving hydrops (such as ascites or polyhydramnios) were present, or when there were very large lesions or lesions rapidly increasing in size. If there were multiple large cysts within the lesion, a single shunt was used, aiming to traverse several cysts.

RESULTS

Shunts were inserted at a mean gestational age of 24.6 (range, 17-32) weeks. Marked mediastinal shift was present in all cases. Six fetuses were hydropic and, of the remaining five, one had severe polyhydramnios, three had lesions that were rapidly increasing in size and one had a very large lesion at initial presentation. In total, four cases had polyhydramnios. Shunting one cyst always decompressed the entire lesion and hydrops and/or polyhydramnios resolved in all surviving fetuses. One hydropic fetus that underwent the procedure at 17 weeks died 1 day later. The shunt dislodged in one case and the lesion did not re-expand. No mother went into labor or had ruptured membranes before 35.6 weeks. Mean gestational age at delivery was 38.2 weeks (n = 10). All pregnancies were delivered vaginally, with no maternal complications. All newborns had uneventful lobectomies, and pathology confirmed CCAM in all cases.

CONCLUSION

Fetal thoracoamniotic shunting for large macrocystic CCAM is associated with favorable outcome in most cases, and should be considered in severe cases even before hydrops develops.

MLC tracking for Elekta VMAT: a modelling study

A model has been developed to simulate volumetric modulated arc therapy (VMAT) delivery for Elekta control systems. The model was experimentally validated for static-tumour VMAT delivery and has been applied to the investigation of motion compensation with dynamic multileaf collimator (dMLC) delivery tracking for a series of VMAT lung treatment plans at various control point spacings for five patients. The relative increase in treatment time with dMLC tracking was calculated for four 1D rigid-body motion trajectories, and the effect of the control point spacing, the MLC leaf speed and an increased number of dose levels on the dMLC tracking delivery time evaluated. It has been observed that a faster leaf speed is advantageous for motion trajectories with shorter time periods and larger amplitudes. The accuracy of dMLC tracking was found to increase with a decreased control point spacing and is dependent on the amplitude and time period of the motion trajectory of the target. dMLC tracking is shown to be a promising emerging technology which can confer advantage over breath-hold motion-compensation techniques which more drastically reduce the efficiency of VMAT and are more invasive for the patient.

A stochastic model to simulate the growth of anchorage dependent cells on flat surfaces

A stochastic model is proposed to simulate the growth of anchorage dependent cells on a flat surface. The model, based on representing the cell shapes on the surface as external irregular polygons with the nuclei distributed as a set of Poisson points (producing a modified Voronoi tessellation of 2 space) and incorporating a distribution function to describe cell division of the perimeter cells of the colony, provides data not only on population dynamics but also on the patterns produced by clusters of cells in the colony. These patterns produced by the model are qualitatively similar to observations reported for some cell cultures. The periods of induction, rapid growth, and decreasing growth asymptoting to zero as confluence is reached are predicted by the model. Quantitative comparison with published experimental data for this is good. The specific growth rate computed for the period of rapid growth predicted by the model is dependent on the distribution function describing the cell division time. As the standard deviation of this increases, the specific growth rate decreases as with a consequent increase in time to achieve confluence. The removal of cells from the colony by shear forces or death is considered in the model. As the probability for removal increases, the cell density at confluence and specific growth rate decrease. The clusters of cells, patterns, in the colony are very sensitive to cell removal. By analyzing these patterns in experiments, an estimate of cell removal can be made. The areas covered by cells on a substrate are fractal patterns. The fractal dimension is always greater than 1 and is a function of the removal probability.

Oral versus vaginal misoprostol for induction of labor: a double-blind randomized controlled trial

OBJECTIVE

To determine the efficacy of oral misoprostol (50 microg) administered every 3 hours compared to vaginal misoprostol (50 microg) administered every 6 hours for induction of labor.

STUDY DESIGN

In this double-blind randomized trial, 126 women received misoprostol (50 microg) either orally every 3 hours or vaginally every 6 hours for induction of labor. Outcomes included time from induction to delivery, oxytocin augmentation, incidence of hyperstimulation and tachysystole, mode of delivery, and neonatal outcomes.

RESULTS

Median time to delivery was shorter in those women who were receiving vaginal misoprostol (vaginal 14.3 hours vs oral 23.1 hours; P =.0004) and more women in the oral group required oxytocin augmentation of labor (73% vs 42%) (RR, 1.98; 95% CI, 1.29 to 3.06). The incidence of hyperstimulation was similar between the groups, but there was an increased incidence of tachysystole in the vaginal group (26.5% vs 9.7%)(RR, 2.74; 95% CI, 1.16 to 6.51). There was no difference between the groups with respect to mode of delivery or neonatal outcome.

CONCLUSION

Vaginal misoprostol administered every 6 hours is more effective for induction of labor than oral misoprostol administered every 3 hours. The higher rates of tachysystole with use of vaginal misoprostol in the current study warrant further investigation.

Maximal exercise testing in late gestation: maternal responses

OBJECTIVE

To study the effects of human pregnancy on metabolic and respiratory responses to maximal cycle ergometer testing and to test the hypothesis that the respiratory exchange ratio at maximal exercise and peak postexercise lactate concentration are lower in the pregnant compared with the nonpregnant state and that these effects are associated with lower excess postexercise oxygen consumption during pregnancy.

METHODS

The pregnant (n = 14, mean gestational age 34.7 +/- 0.4 weeks) and nonpregnant control group (n = 14) included healthy, physically active women. Groups were matched for age, height, parity, prepregnant body mass and body mass index (BMI), and aerobic fitness. Breath-by-breath gas exchange was measured at rest, during exercise, and 15 minutes after exercise. The minimum sample size to detect a statistically significant result for a reasonable difference (0.25 L/min) in the ventilatory threshold was calculated to be ten subjects per group; thus, 14 was considered adequate.

RESULTS

Maximal oxygen uptake, the ventilatory threshold, the point of respiratory compensation, and calculated work efficiency did not differ significantly between groups. However, the respiratory exchange ratio at maximal exercise, peak postexercise lactate, and excess postexercise oxygen consumption were significantly lower in the pregnant group. Peak lactate was significantly correlated with the respiratory exchange ratio and excess postexercise oxygen consumption.

CONCLUSION

The capacity for weight-supported work is preserved in late gestation, and work efficiency is unchanged. However, carbohydrate utilization might be blunted at high levels of exertion. Blunted respiratory responses were attributed to reduced lactate production and/or dilution of lactate in an expanded blood volume.

Effects of human pregnancy on cardiac autonomic function above and below the ventilatory threshold

This study examined the effects of human pregnancy on heart rate variability (HRV), spontaneous baroreflex (SBR) sensitivity, and plasma catecholamines at rest and during exercise. Subjects were 14 healthy, physically active pregnant women (PG; mean gestational age = 33.9 +/- 1.0 wk). Results were compared with an age-matched nonpregnant control group (NPG; n = 14) with similar characteristics. The electrocardiographic R-wave-R-wave interval and systolic blood pressure (via finger plethysmograph) were measured on a beat-to-beat basis at rest and during upright cycling at 60 and 110% of the ventilatory threshold (T(vent)). Parasympathetic nervous system (PNS) modulation (as reflected by HRV high-frequency/total power and SBR slope) was significantly reduced at rest in the PG vs. the NPG. During exercise, PNS modulation decreased significantly in both groups, but the magnitude of PNS withdrawal from rest to 110% T(vent) was smaller in the PG vs. NPG. Sympathetic nervous system (SNS) modulation (reflected by the low-frequency power-to-high-frequency power ratio) increased above resting values at 60 and 110% T(vent) in the NPG. SNS modulation at 110% T(vent) was significantly lower in the PG compared with the NPG. Plasma norepinephrine and epinephrine levels were also lower at 110% T(vent) in the PG. It was concluded that healthy pregnant women exhibit lower PNS modulation at rest and blunted SNS modulation during exercise above T(vent) in late gestation.

A comparison of oral and vaginal misoprostol for induction of labour at term: a randomised trial

OBJECTIVE

To compare the efficacy of oral with vaginal misoprostol for induction of labour at term.

DESIGN

Randomised trial.

SETTING

Tertiary Care hospital.

PARTICIPANTS

One hundred and sixty-seven women requiring induction of labour.

METHODS

The women were randomised to receive 50 microg of misoprostol orally or vaginally every 6 h until the cervix was favourable for amniotomy, spontaneous rupture of membranes, or active labour occurred. Sample size was calculated with a two-tailed alpha of 0.05 and a power of 95% to detect a 5 h difference in induction-to-delivery time. Student's t test was used for comparison of normally distributed continuous variables and the Mann-Whitney U test was used for non-Gaussian distributed continuous variables. Fisher' s exact and chi2 tests were used for comparison of categorical variables. The main outcome measure was induction to delivery time.

RESULTS

The median induction to delivery time was significantly shorter with vaginal misoprostol (15.7 h range 4.3-55.7), compared with oral misoprostol (23.0 h range 3.2-141.7, P = 0.0013). The median number of doses was also significantly less in the vaginal misoprostol group, 1 (range 1-3), compared with the oral group, 2 (range 1-8), (P < 0.0001). The significant differences in outcome held true when nulliparous and multiparous women were analysed separately. There were no differences between the two routes of administration with respect to rates of hyperstimulation or neonatal asphyxia. There were more caesarean sections in the vaginal misoprostol group, but the difference was not statistically significant.

CONCLUSIONS

Compared with oral misoprostol, vaginal misoprostol for induction of labour at term results in a shorter induction-to-delivery time, with fewer doses required per patient. Vaginal misoprostol may be associated with higher rates of caesarean section than oral misoprostol.