Imperial College London

DrChloeBloom

Faculty of MedicineNational Heart & Lung Institute

Clinical Senior Lecturer in Respiratory Epidemiology
 
 
 
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Contact

 

chloe.bloom06

 
 
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Location

 

Emmanuel Kaye BuildingRoyal Brompton Campus

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Summary

 

Publications

Publication Type
Year
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101 results found

Bloom CI, Adcock IM, 2023, CC16: A Treatable Trait in Asthma?, Am J Respir Crit Care Med

Journal article

Bloom C, 2023, Covid‐19 pandemic and asthma: what did we learn?, Respirology, Vol: 28, Pages: 603-614, ISSN: 1323-7799

This review addresses some of the major lessons we have learnt regarding asthma and the covid-19 pandemic, including susceptibility to SARS-CoV-2 infection and severe covid-19, potentially protective factors, comparison to other respiratory infections, changes in healthcare behaviour from the perspective of patients and clinicians, medications to treat or prevent covid-19, and post-covid syndrome.

Journal article

Ritchie AI, Singayagam A, Mitchell S, Wedzicha JA, Shah A, Bloom CIet al., 2023, The effect of inhaled corticosteroids on pneumonia risk in patients with COPD-bronchiectasis overlap: a UK population-based case-control study, Chest, ISSN: 0012-3692

BackgroundInhaled corticosteroids (ICS) increase the risk of pneumonia in COPD and are commonly used in patients with COPD-bronchiectasis overlap.Research QuestionIs the risk of pneumonia associated with ICS further heightened in COPD-bronchiectasis?Study Design and MethodsElectronic healthcare records (2004-2019) were used to obtain a cohort of COPD patients and a nested case-control (age-gender matched 1:4). Analyses were conducted to determine the risk of hospitalised pneumonia in COPD associated with ICS use in those with bronchiectasis. Findings were confirmed by several sensitivity analyses. Additionally, a smaller nested case-control, containing only patients with COPD-bronchiectasis overlap and those with recent blood eosinophil counts (BEC), was used to determine any association with BEC.Results316,663 were eligible for the COPD cohort; bronchiectasis significantly increased the risk of pneumonia (AHR=1.24, 95% CI 1.15-1.33). In the first nested case-control of 84,316 COPD patients, ICS was found to increase the odds of pneumonia (AOR=1.26, 95% CI 1.19-1.32), only if used in the previous 180 days. However, bronchiectasis was a significant modifier such that ICS use did not further augment the already elevated bronchiectasis-associated pneumonia risk (AOR, 95% CI: COPD-bronchiectasis=1.01, 0.8-1.28; no bronchiectasis=1.27, 1.20-1.34). Several sensitivity analyses and a second smaller nested case-control, confirmed these findings. Lastly, we found BEC modified the ICS-associated pneumonia risk in COPD-bronchiectasis overlap, where lower BEC was significantly associated with pneumonia (AOR, 95% CI: BEC≤3x109/L=1.56, 1.05-2.31, BEC>3x109/L=0.89, 0.53-1.24).InterpretationICS use does not further augment the already increased risk of hospitalised pneumonia associated with concomitant bronchiectasis in COPD.

Journal article

Valencia-Hernandez CA, Zakeri R, Sundaram V, Bloom CIet al., 2022, INCREASED RISK OF CARDIOVASCULAR DISEASE IN ASTHMA, Publisher: BMJ PUBLISHING GROUP, Pages: A47-A48, ISSN: 0040-6376

Conference paper

Khalaf Z, Saglani S, Bloom CI, 2022, CHARACTERISING SCHOOL-AGE CHILDREN WITH ASTHMA: ENGLISH POPULATION-COHORT STUDY, Publisher: BMJ PUBLISHING GROUP, Pages: A23-A23, ISSN: 0040-6376

Conference paper

Ritchie AI, Singanayagam A, Mitchell S, Wedzicha J, Shah A, Bloom Cet al., 2022, THE RISK OF PNEUMONIA IN COPD PATIENTS WITH CONCOMITANT BRONCHIECTASIS USING INHALED CORTICOSTEROIDS: A UK CASE-CONTROL STUDY, Publisher: BMJ PUBLISHING GROUP, Pages: A70-A70, ISSN: 0040-6376

Conference paper

Price LC, Garfield B, Bloom C, Jeyin N, Nissan D, Hull JH, Patel B, Jenkins G, Padley S, Man W, Singh S, Ridge CAet al., 2022, Persistent isolated impairment of gas transfer following COVID-19 pneumonitis relates to perfusion defects on dual-energy computed tomography, ERJ Open Research, Vol: 8, Pages: 1-5, ISSN: 2312-0541

Journal article

Conway FM, Bloom CI, Shah PL, 2022, Susceptibility of patients with airways disease to SARS-CoV-2 infection., American Journal of Respiratory and Critical Care Medicine, Vol: 206, Pages: 696-703, ISSN: 1073-449X

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to a worldwide pandemic. People with airways disease are at higher risk of respiratory infection, and viruses can trigger respiratory exacerbations. Patients with airways disease may therefore be more susceptible to SARS-CoV-2 infection, development of covid-19, or be at higher risk of adverse outcomes. Here we review susceptibility, based on current epidemiological studies, and explore biological mechanisms. Evidence from multiple large observational studies has shown chronic obstructive pulmonary disease (COPD) is a significant risk factor for covid-19 related mortality. Whether people with asthma are more susceptible to infection or severe outcomes has been much debated but appears to be related to their asthma phenotype and severity. To what extent these differences are biological or influenced by public health non-pharmacological interventions is difficult to quantify. Biological mechanisms that may influence susceptibility and adverse outcomes in airways disease include the increased expression of protein receptors enabling viral cell entry, dysfunctional epithelial airway immunity, type-2 inflammation and the use of inhaled corticosteroids. A better understanding of the susceptibility and mechanisms is essential for developing preventative and therapeutic strategies. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Journal article

Sundaram V, Nagai T, Chiang C-E, Reddy YN, Chao T-F, Zakeri R, Bloom C, Nakai M, Nishimura K, Hung C-L, Miyamoto Y, Yasuda S, Banerjee A, Anzai T, Simon D, Rajagopalan S, Cleland JGF, Sahadevan J, Quint JKet al., 2022, Hospitalization for Heart Failure in the United States, UK, Taiwan, and Japan: An International Comparison of Administrative Health Records on 413,385 Individual Patients, JOURNAL OF CARDIAC FAILURE, Vol: 28, Pages: 353-366, ISSN: 1071-9164

Journal article

Bloom C, Montonen J, Jons O, Garry EM, Bhatt SPet al., 2022, First Maintenance Therapy for Chronic Obstructive Pulmonary Disease: Retrospective Analyses of US and UK Healthcare Databases, PULMONARY THERAPY, Vol: 8, Pages: 57-74, ISSN: 2364-1754

Journal article

Bloom C, Montonen J, Jons O, Garry EM, Bhatt SPet al., 2022, Treatment Transitions in Chronic Obstructive Pulmonary Disease: Retrospective Analyses of US and UK Healthcare Databases, PULMONARY THERAPY, Vol: 8, Pages: 75-93, ISSN: 2364-1754

Journal article

Bloom C, Wong E, Hickman K, Elkin Set al., 2021, Influence of the first wave of COVID-19 on asthma inhaler prescriptions, npj Primary Care Respiratory Medicine, Vol: 31, ISSN: 2055-1010

In the beginning of the COVID-19 pandemic there were major concerns regarding the huge demand for asthma inhalers. Using primary care medical records for 614,700 asthma patients between January and June 2020, we found that there was a substantial increase in inhalers solely in March 2020. Patients significantly associated with receiving higher inhaled corticosteroid prescriptions were younger, of higher socioeconomic status and had milder asthma.

Journal article

Bloom CI, Johnston SL, 2021, Decline in respiratory and cardiac admissions during the COVID-19 pandemic: what is the role of common respiratory virus infections?, Respirology, Vol: 26, Pages: 1010-1011, ISSN: 1323-7799

Numerous countries across the globe have introduced a variety of public health measures, non-pharmaceutical interventions (NPIs), to reduce the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and accordingly reduce coronavirus disease 2019 (COVID-19) hospitalizations and mortality. Effective NPIs have at the same time caused considerable changes in healthcare demand for non-COVID-19 conditions. In New Zealand, during the first wave of the pandemic in early 2020, their government instigated a stringent programme of restrictions, with a four-level alert system, including border closure, quarantine for returning travellers, social distancing measures and personal hygiene promotion. High public compliance with NPIs prevented COVID-19 community transmission for 102 consecutive days. In fact, they were so effective that the usual winter influenza surge was also disrupted, with an extraordinary 99.9% reduction in influenza virus detections as compared to previous years and a substantial reduction in all other respiratory viruses, including a 98% reduction in respiratory syncytial virus detections.1 Due to the key role viruses are known to play in many respiratory conditions and are postulated to play in myocardial infarctions and heart failure, it may be hypothesized that the stringent reductions implemented in New Zealand may also have mitigated the incidence of these conditions during that time.

Journal article

Bloom CI, Cullinan P, Wedzicha JA, 2021, Asthma phenotypes and COVID-19 risk: a population-based observational study, American Journal of Respiratory and Critical Care Medicine, Vol: 205, Pages: 36-45, ISSN: 1073-449X

Rationale: Studies have suggested some asthma patients are at risk of severe COVID-19, but they have had limited data on asthma phenotype and have not considered if risks are specific to COVID-19. Objectives: Determine the effect of asthma phenotype on three levels of COVID-19 outcomes. Compare hospitalisation rates to influenza and pneumonia. Methods: Electronic medical records were used to identify asthma patients and match them to the general population. Patient-level data were linked to Public Health England SARS-CoV-2 test data, hospital, and mortality data. Asthma was phenotyped by medication, exacerbation history, and type-2 inflammation. The risk of each outcome, adjusted for major risk factors, was measured using Cox regression. Measurements and Main Results: 434,348 asthma and 748,327 matched patients were included. All asthma patients had a significantly increased risk of a GP-diagnosis of COVID-19. Asthma with regular inhaled corticosteroid (ICS) use (HR=1.27, 95%CI=1.01-1.61), intermittent ICS + add-on asthma medication use (HR=2.00, 95%CI=1.43-2.79), regular ICS + add-on use (HR=1.63, 95 CI=1.37-1.94), or with frequent exacerbations (HR=1.82, 95% CI=1.34-2.47) was significantly associated with hospitalisation. These phenotypes were significantly associated with influenza and pneumonia hospitalisations. Only patients with regular ICS + add-on asthma therapy (HR=1.70, 95%CI=1.27-2.26) or frequent exacerbations (HR=1.66, 95%CI=1.03-2.68) had a significantly higher risk of ICU admission or death. Atopy and blood eosinophil count were not associated with severe COVID-19 outcomes. Conclusions: More severe asthma was associated with more severe COVID-19 outcomes, but type-2 inflammation was not. The risk of COVID-19 hospitalisation appeared to be similar to the risk with influenza or pneumonia.

Journal article

Zakeri R, Morgan A, Sundaram V, Bloom C, Cleland J, Quint Jet al., 2021, Under-recognition of heart failure in patients with atrial fibrillation and the impact of gender: a UK population-based cohort study, BMC Medicine, Vol: 19, ISSN: 1741-7015

Background: Patients with atrial fibrillation (AF) complicated by heart failure (HF) have a poor prognosis. We investigated whether long-term loop-diuretic therapy in patients with AF and no known diagnosis of HF, as a potential surrogate marker of undiagnosed HF, is also associated with worse outcomes.Methods: Adults with incident AF were identified from UK primary and secondary care records between 2004-2016. Repeat prescriptions for loop-diuretics, without a diagnosis of HF or documented non-cardiac indication, were classified as ‘isolated’ loop-diuretic use.Results: Amongst 124,256 people with incident AF (median 76 years, 47% women), 22,001 (17.7%) had a diagnosis of HF, and 22,325 (18.0%) had isolated loop-diuretic use. During 2.9 (LQ-UQ 1-6) years’ follow-up, 12,182 patients were diagnosed with HF (incidence rate 3.2 [95%CI 3.1-3.3]/100 person-years). Of these, 3,999 (32.8%) had prior isolated loop-diuretic use, including 31% of patients diagnosed with HF following an emergency hospitalisation. The median time from AF to HF diagnosis was 3.6 (1.2-7.7) years in men versus 5.1 (1.8-9.9) years in women (p=0.0001). In adjusted models, patients with isolated loop-diuretic use had higher mortality (HR 1.42 [95%CI 1.37-1.47], p<0.0005) and risk of HF hospitalisation (HR 1.60 [95%CI 1.42-1.80], p<0.0005) than patients with no HF or loop-diuretic use, and comparably poor survival to patients with diagnosed HFConclusions: Loop-diuretics are commonly prescribed to patients with AF and may indicate increased cardiovascular risk. Targeted evaluation of these patients may allow earlier HF diagnosis, timely intervention and better outcomes, particularly amongst women with AF, in whom HF appears to be under-recognised and diagnosed later than in men.

Journal article

Altmann MC, Rinchai D, Baldwin N, Toufiq M, Whalen E, Garand M, Kabeer BSA, Alfaki M, Presnell S, Khaenam P, Benitez AA, Mougin F, Thébault P, Chiche L, Jourde-Chiche N, Phillips JT, Klintmalm G, O'Garra A, Berry M, Bloom C, Wilkinson RJ, Graham CM, Lipman M, Lertmemongkolchai G, Bedognetti D, Thiebaut R, Kheradmand F, Mejias A, Ramilo O, Palucka K, Pascual V, Banchereau J, Chaussabel Det al., 2021, Development of a fixed module repertoire for the analysis and interpretation of blood transcriptome data, Nature Communications, Vol: 12, Pages: 1-19, ISSN: 2041-1723

As the capacity for generating large-scale molecular profiling data continues to grow, the ability to extract meaningful biological knowledge from it remains a limitation. Here, we describe the development of a new fixed repertoire of transcriptional modules, BloodGen3, that is designed to serve as a stable reusable framework for the analysis and interpretation of blood transcriptome data. The construction of this repertoire is based on co-clustering patterns observed across sixteen immunological and physiological states encompassing 985 blood transcriptome profiles. Interpretation is supported by customized resources, including module-level analysis workflows, fingerprint grid plot visualizations, interactive web applications and an extensive annotation framework comprising functional profiling reports and reference transcriptional profiles. Taken together, this well-characterized and well-supported transcriptional module repertoire can be employed for the interpretation and benchmarking of blood transcriptome profiles within and across patient cohorts. Blood transcriptome fingerprints for the 16 reference cohorts can be accessed interactively via: https://drinchai.shinyapps.io/BloodGen3Module/.

Journal article

Bloom CI, Drake TM, Docherty AB, Lipworth BJ, Johnston SL, Nguyen-Van-Tam JS, Carson G, Dunning J, Harrison EM, Baillie JK, Semple MG, Cullinan P, Openshaw PJM, Alex B, Bach B, Barclay WS, Bogaert D, Chand M, Cooke GS, Filipe AD, Fletcher T, Green CA, Harrison EM, Hiscox JA, Ho AY, Horby PW, Ijaz S, Khoo S, Klenerman P, Law A, Lim WS, Mentzer AJ, Merson L, Meynert AM, Noursadeghi M, Moore SC, Palmarini M, Paxton WA, Pollakis G, Price N, Rambaut A, Robertson DL, Russell CD, Sancho-Shimizu V, Scott JT, Silva TD, Sigfrid L, Solomon T, Sriskandan S, Stuart D, Summers C, Tedder RS, Thomson EC, Thompson AAR, Thwaites RS, Turtle LCW, Zambon M, Hardwick H, Donohue C, Lyons R, Griffiths F, Oosthuyzen W, Norman L, Pius R, Fairfield CJ, Knight SR, Mclean KA, Murphy D, Shaw CA, Dalton J, Girvan M, Saviciute E, Roberts S, Harrison J, Marsh L, Connor M, Halpin S, Jackson C, Gamble C, Leeming G, Law A, Wham M, Clohisey S, Hendry R, Scott-Brown J, Greenhalf W, Shaw V, McDonald S, Keating S, Ahmed KA, Armstrong JA, Ashworth M, Asiimwe IG, Bakshi S, Barlow SL, Booth L, Brennan B, Bullock K, Catterall BWA, Clark JJ, Clarke EA, Cole S, Cooper L, Cox H, Davis C, Dincarslan O, Dunn C, Dyer P, Elliott A, Evans A, Finch L, Fisher LWS, Foster T, Garcia-Dorival I, Greenhalf W, Gunning P, Hartley C, Jensen RL, Jones CB, Jones TR, Khandaker S, King K, Kiy RT, Koukorava C, Lake A, Lant S, Latawiec D, Lavelle-Langham L, Lefteri D, Lett L, Livoti LA, Mancini M, McDonald S, McEvoy L, McLauchlan J, Metelmann S, Miah NS, Middleton J, Mitchell J, Moore SC, Murphy EG, Penrice-Randal R, Pilgrim J, Prince T, Reynolds W, Ridley PM, Sales D, Shaw VE, Shears RK, Small B, Subramaniam KS, Szemiel A, Taggart A, Tanianis-Hughes J, Thomas J, Trochu E, Tonder LV, Wilcock E, Zhang JE, Flaherty L, Maziere N, Cass E, Carracedo AD, Carlucci N, Holmes A, Massey H, Adeniji K, Agranoff D, Agwuh K, Ail D, Alegria A, Angus B, Ashish A, Atkinson D, Bari S, Barlow G, Barnass S, Barrett N, Bassford C, Baxter D, Beadsworth Met al., 2021, Risk of adverse outcomes in patients with underlying respiratory conditions admitted to hospital with COVID-19: a national, multicentre prospective cohort study using the ISARIC WHO Clinical Characterisation Protocol UK, The Lancet Respiratory Medicine, Vol: 9, Pages: 699-711, ISSN: 2213-2600

BackgroundStudies of patients admitted to hospital with COVID-19 have found varying mortality outcomes associated with underlying respiratory conditions and inhaled corticosteroid use. Using data from a national, multicentre, prospective cohort, we aimed to characterise people with COVID-19 admitted to hospital with underlying respiratory disease, assess the level of care received, measure in-hospital mortality, and examine the effect of inhaled corticosteroid use.MethodsWe analysed data from the International Severe Acute Respiratory and emerging Infection Consortium (ISARIC) WHO Clinical Characterisation Protocol UK (CCP-UK) study. All patients admitted to hospital with COVID-19 across England, Scotland, and Wales between Jan 17 and Aug 3, 2020, were eligible for inclusion in this analysis. Patients with asthma, chronic pulmonary disease, or both, were identified and stratified by age (<16 years, 16–49 years, and ≥50 years). In-hospital mortality was measured by use of multilevel Cox proportional hazards, adjusting for demographics, comorbidities, and medications (inhaled corticosteroids, short-acting β-agonists [SABAs], and long-acting β-agonists [LABAs]). Patients with asthma who were taking an inhaled corticosteroid plus LABA plus another maintenance asthma medication were considered to have severe asthma.Findings75 463 patients from 258 participating health-care facilities were included in this analysis: 860 patients younger than 16 years (74 [8·6%] with asthma), 8950 patients aged 16–49 years (1867 [20·9%] with asthma), and 65 653 patients aged 50 years and older (5918 [9·0%] with asthma, 10 266 [15·6%] with chronic pulmonary disease, and 2071 [3·2%] with both asthma and chronic pulmonary disease). Patients with asthma were significantly more likely than those without asthma to receive critical care (patients aged 16–49 years: adjusted odds ratio [OR] 1·20 [95% CI

Journal article

Cook J, Bloom C, Lewis J, Marjenberg Z, Platz JH, Langham Set al., 2021, Impact of health technology assessment on prescribing patterns of inhaled fixed-dose combination triple therapy in chronic obstructive pulmonary disease., J Mark Access Health Policy, Vol: 9, Pages: 1-10, ISSN: 2001-6689

Background: Evidence suggests that triple therapy for patients with chronic obstructive pulmonary disease (COPD) is being used in a broader range of patients than recommended by guidelines, which may have health and cost implications. Objective: To explore the relationship between national health technology assessment (HTA) agency appraisals and market penetration of two fixed-dose combination (FDC) triple therapies. Study design: HTAs from Q3 2017 to Q1 2020 from 10 countries were evaluated. Intervention: Glycopyrronium bromide/formoterol fumarate/beclomethasone (Trimbow®) and umeclidinium/vilanterol/fluticasone furoate (Trelegy™ Ellipta®). Main outcome measure: HTA restrictions and prescribing rates (days of therapy). Results: Seven countries (70%) imposed restrictions on use including prescription only for patients stable on free-combination triple therapy or not controlled on dual therapy, requirement of a specialist prescription or therapeutic plan, prescription only for patients with severe COPD, and use as second-line therapy or later. In general, countries that have imposed restrictions on the use of FDC triple therapies have seen a lower than average uptake. Conclusion: Payer guidance on prescribing FDC triple therapy may potentially support more appropriate prescribing in line with clinical guidelines. It is important for payers to consider which restrictions would ensure the most efficient use of scarce resources.

Journal article

Bloom CI, Cullinan P, Wedzicha JA, 2021, Assessing Factors Associated with COVID19 Risk in Asthma, International Conference of the American-Thoracic-Society (ATS), Publisher: AMER THORACIC SOC, ISSN: 1073-449X

Conference paper

Bloom C, Franklin C, Bush A, Saglani S, Quint Jet al., 2021, Burden of preschool wheeze and progression to asthma in the UK: population-based cohort 2007 to 2017, Journal of Allergy and Clinical Immunology, Vol: 147, Pages: 1949-1958, ISSN: 0091-6749

BackgroundWheeze is one of the most common symptoms of preschool children (age 1 to 5 years), yet we have little understanding of the burden in the UK.ObjectivesDetermine prevalence and pattern of physician-confirmed preschool wheeze, related healthcare utilisation, and factors associated with progression to school-age asthma.MethodsWe used nationally representative primary and secondary care electronic medical records between 2007-2017 to identify preschool children with wheeze. Factors associated with asthma progression were identified in a nested cohort of children with follow-up from 1-2 years of age, until at least 8 years of age.ResultsFrom 1,021,624 preschool children, 69,261 were identified with wheeze. Prevalence of preschool wheeze was 7.7% in 2017. Wheeze events were lowest in August and highest in late-autumn/early-winter. During median follow-up of 2.0 years (IQR 1.2-4.0), 15.8% attended an emergency department, and 13.9% had a hospital admission, for a respiratory disorder. The nested cohort with prolonged follow-up identified 15,085 children; 35.5% progressed to asthma between 5-8 years old. Of children with preschool wheeze, without an asthma diagnosis, 34.9% were prescribed inhaled corticosteroids, and 15.6% oral corticosteroids. The factors most strongly associated with progression to asthma were wheeze frequency and severity, atopy, prematurity, maternal asthma severity and first reported wheeze event occurring in September.ConclusionsPreschool wheeze causes considerable healthcare burden, a large number of children are prescribed asthma medication and have unplanned secondary care visits. Multiple factors influence progression to asthma, including first wheeze event occurring in September.

Journal article

Mallia P, Russell G, Meghji J, Wong B, Kumar K, Pilkington V, Chhabra S, Russell B, Chen J, Srikanthan K, Park M, Owles H, Liew F, Alcada J, Martin L, Coleman M, Elkin S, Ross C, Agrawal S, Gardiner T, Bell A, White A, Hampson D, Vithlani G, Manalan K, Bramer S, Martin S, Kucheria A, Ratnakumar P, Sheeka A, Anandan L, Copley S, Bloom C, Kon Oet al., 2021, Symptomatic, biochemical and radiographic recovery in patients with Covid-19, BMJ Open Respiratory Research, Vol: 8, ISSN: 2052-4439

Background: The symptoms, radiography, biochemistry and healthcare utilisation of patients with COVID-19 following discharge from hospital have not been well described.Methods: Retrospective analysis of 401 adult patients attending a clinic following an index hospital admission or emergency department attendance with COVID-19. Regression models were used to assess the association between characteristics and persistent abnormal chest radiographs or breathlessness.Results: 75.1% of patients were symptomatic at a median of 53 days post discharge and 72 days after symptom onset and chest radiographs were abnormal in 47.4%. Symptoms and radiographic abnormalities were similar in PCR-positive and PCR-negative patients. Severity of COVID-19 was significantly associated with persistent radiographic abnormalities and breathlessness. 18.5% of patients had unscheduled healthcare visits in the 30 days post discharge.Conclusions: Patients with COVID-19 experience persistent symptoms and abnormal blood biomarkers with a gradual resolution of radiological abnormalities over time. These findings can inform patients and clinicians about expected recovery times and plan services for follow-up of patients with COVID-19.

Journal article

Whittaker H, Bloom C, Morgan A, Jarvis D, Kiddle S, Quint Jet al., 2021, Accelerated FEV1 decline and risk of cardiovascular disease and mortality in a primary care population of COPD patients, European Respiratory Journal, Vol: 57, ISSN: 0903-1936

Accelerated lung function decline has been associated with increased risk of cardiovascular disease (CVD) in a general population, but little is known about this association in chronic obstructive pulmonary disease (COPD). We investigated the association between accelerated lung function decline and CVD outcomes and mortality in a primary care COPD population.COPD patients without a history of CVD were identified in the Clinical Practice Research Datalink (CPRD-GOLD) primary care dataset (n=36 282). Accelerated FEV1 decline was defined using the fastest quartile of the COPD population's decline. Cox regression assessed the association between baseline accelerated FEV1 decline and a composite CVD outcome over follow-up (myocardial infarction, ischaemic stroke, heart failure, atrial fibrillation, coronary artery disease, and CVD mortality). The model was adjusted for age, gender, smoking status, BMI, history of asthma, hypertension, diabetes, statin use, mMRC dyspnoea, exacerbation frequency, and baseline FEV1 percent predicted.6110 (16.8%) COPD patients had a CVD event during follow-up; median length of follow-up was 3.6 years [IQR 1.7–6.1]). Median rate of FEV1 decline was –19.4 mL·year−1 (IQR, –40.5 to 1.9); 9095 (25%) patients had accelerated FEV1 decline (>–40.5 mL·year−1), 27 287 (75%) did not (≤ –40.5 mL·year−1). Risk of CVD and mortality was similar between patients with and without accelerated FEV1 decline (HRadj 0.98 [95%CI, 0.90–1.06]). Corresponding risk estimates were 0.99 (95%CI 0.83–1.20) for heart failure, 0.89 (95%CI 0.70–1.12) for myocardial infarction, 1.01 (95%CI 0.82–1.23) for stroke, 0.97 (95%CI 0.81–1.15) for atrial fibrillation, 1.02 (95%CI 0.87–1.19) for coronary artery disease, and 0.94 (95%CI 0.71–1.25) for CVD mortality. Rather, risk of CVD was associated with mMRC score ≥2 and ≥2 exacerbations in the year prior.CVD out

Journal article

Naqvi SA, Patel R, Griffiths CJ, Bloom CIet al., 2021, P114 Systemic adverse effects from inhaled corticosteroid use in asthma: a systematic review, British Thoracic Society Winter Meeting, Publisher: BMJ Publishing Group, Pages: A151-A151, ISSN: 0040-6376

Background Oral corticosteroid (OCS) use increases the risk of systemic adverse effects including osteoporosis, fractures, diabetes, ocular disorders and respiratory infections. We sought to understand if there is an increased risk of these adverse effects from inhaled corticosteroids (ICS) use in adults with asthma.Methods MEDLINE and EMBASE databases were searched to identify studies measuring adverse effects with ICS use in asthma, with those investigating a majority population of COPD patients excluded. Studies were grouped by outcome: bone mineral density (BMD), respiratory infection (pneumonia, tuberculous or non-tuberculous mycobacterial infection), diabetes and ocular disorder (glaucoma or cataracts). Study information was extracted using the PICO checklist. Risk of bias was assessed using the Cochrane Risk of Bias tool (randomised controlled trials) and ROBINS-I tool (observational studies). A narrative synthesis was carried out due to the low number of studies with the same outcome measurement.Results Thirteen studies met the inclusion criteria, two trials and eleven observational studies, all analysing the effects of ICS compared with non-ICS use for particular outcomes. Study outcomes by number of studies were: six BMD, six infection (four pneumonia, one tuberculous, one non-tuberculous mycobacterial), one ocular disorder (cataracts) and no diabetes. Studies addressing BMD were limited by study size, lack of generalisability, and short follow-up. BMD was measured from a range of bones via ultrasound or x-ray absorptiometry; most found a loss of BMD. Studies addressing infection suffered from lack of power, misclassification and selection bias; most studies found an increased risk of infection. Only one study assessed ocular disorders, they found an increased risk of cataracts. This study likely suffered from residual confounding. Most studies were unable to fully account for OCS exposure, total ICS exposure or difference between ICS drugs and their varyi

Conference paper

Patel R, Naqvi S, Griffiths C, Bloom Cet al., 2020, Systemic adverse effects from inhaled corticosteroid use in asthma: a systematic review, BMJ Open Respiratory Research, Vol: 7, ISSN: 2052-4439

Background Oral corticosteroid use increases the risk of systemic adverse effects including osteoporosis, bone fractures, diabetes, ocular disorders and respiratory infections. We sought to understand if inhaled corticosteroid (ICS) use in asthma is also associated with increased risk of systemic effects.Methods MEDLINE and Embase databases were searched to identify studies that were designed to investigate ICS-related systemic adverse effects in people with asthma. Studies were grouped by outcome: bone mineral density (BMD), respiratory infection (pneumonia or mycobacterial infection), diabetes and ocular disorder (glaucoma or cataracts). Study information was extracted using the PICO checklist. Risk of bias was assessed using the Cochrane Risk of Bias tool (randomised controlled trials) and Risk of Bias In Non-randomised Studies of Interventions-I tool (observational studies). A narrative synthesis was carried out due to the low number of studies reporting each outcome.Results Thirteen studies met the inclusion criteria, 2 trials and 11 observational studies. Study numbers by outcome were: six BMD, six respiratory infections (four pneumonia, one tuberculosis (TB), one non-TB mycobacteria), one ocular disorder (cataracts) and no diabetes. BMD studies found conflicting results (three found loss of BMD and three found no loss), but were limited by study size, short follow-up and lack of generalisability. Studies addressing infection risk generally found positive associations but suffered from a lack of power, misclassification and selection bias. The one study which assessed ocular disorders found an increased risk of cataracts. Most studies were not able to fully adjust for known confounders, including oral corticosteroids.Conclusion There is a paucity of studies assessing systemic adverse effects associated with ICS use in asthma. Those studies that have been carried out present conflicting findings and are limited by multiple biases and residual confounding. Furth

Journal article

Bloom C, Ramsey H, Alter M, Lakhani S, Wong E, Hickman K, Elkin S, Majeed A, El-Osta Aet al., 2020, Qualitative study of practices and challenges of stepping down asthma medication in primary care across the UK, Journal of Asthma and Allergy, Vol: 13, Pages: 429-437, ISSN: 1178-6965

Background: Guidelines recommend that asthma treatment should be stepped down to the minimally effective dose that achieves symptom control to prevent medication side effects and reduce unnecessary costs. Little is known about the practice of stepping down and the challenges in primary care, where most asthma patients are managed.Objective: To explore views, experiences, barriers and ideas, of doctors, nurses and pharmacists working in primary care, related to step down of asthma medication.Methods: Primary care practitioners from across the UK participated in a survey and/or semi-structured interview. Questions explored four main areas: how asthma medication is reviewed, views on asthma guidelines, perceived barriers faced by healthcare workers and facilitators of stepping down. Qualitative content analysis enabled data coding of interview transcripts to identify major themes.Results: A total of 274 participants responded to the survey, 29 participated in an interview (12 doctors, 9 nurses, and 8 pharmacists), working in GP practices from across the UK. Nearly half of the survey participants infrequently step down asthma medication (doctors=42.7%, nurses=46.3%). Four major themes related to barriers to stepping down were (i) lack of awareness of the need to step down, (ii) inertia to step down, driven by low confidence in ability, fear of consequences, and concern for who is responsible for stepping down, (iii) self-efficacy of ability to step down, influenced by lack of clear, applied guidance and limited training, and (iv) feasibility of step down, driven by a lack of systematic acceptance of stepping down and time. Strategies proposed to reduce overtreatment included education and training, improved gathering of evidence and guidance, and integrating step down into routine asthma care.Conclusion: Failure to implement this guideline recommendation into everyday asthma management is influenced by several contributing factors. Future directions should include addre

Journal article

Bloom CI, Cabrera C, Arnetorp S, Coulton K, Nan C, van der Valk RJP, Quint JKet al., 2020, Asthma-related health outcomes associated with short-acting beta(2)-agonist inhaler use: an observational UK study as part of the SABINA global program, Advances in Therapy, Vol: 37, Pages: 4190-4208, ISSN: 0741-238X

IntroductionPatients with asthma typically increase short-acting β2-agonists (SABA) use with worsening symptoms. Excessive SABA use may lead to a higher risk of adverse outcomes. We evaluated, in a large population cohort, an association between SABA inhaler use and asthma exacerbations and healthcare utilization.MethodsAs part of the SABINA (SABA use IN Asthma) global program, we conducted a retrospective longitudinal observational study (SABINA I) using UK primary care electronic healthcare records (Clinical Practice Research Datalink; 2007–2017) from asthma patients aged ≥ 12 years. SABA inhaler use was classified as ‘high use ’ 3 canisters/year versus ‘low use’, 0–2 canisters/year. Taking into consideration all their asthma prescriptions, patients were categorized into a treatment step according to 2016 British Thoracic Society (BTS) asthma management guidelines. Multivariable regression assessed the association of SABA inhaler use by BTS treatment steps (grouped as BTS steps 1/2 and 3–5), separately, and with outcomes of exacerbations or asthma-related healthcare utilization (primary care and hospital outpatient consultations); only patients with linked hospital data were included in this analysis.ResultsOf the 574,913 patients included, 218,365 (38%) had high SABA inhaler use. Overall, 336,412 patients had linked hospital data. High SABA inhaler use was significantly associated with an increased risk of exacerbations [adjusted hazard ratio, 95% confidence interval (CI): BTS steps 1/2 = 1.20, 1.16–1.24; BTS steps 3–5 = 1.24, 1.20–1.28], asthma-related primary care consultations [adjusted incidence rate ratio (IRR), 95% CI: BTS steps 1/2 = 1.24, 1.23–1.26; BTS steps 3–5 = 1.13, 1.11–1.15), and asthma-related hospital outpatient consultations (adjusted IRR, 95% CI: BTS steps 1/2 = 1.19, 1.12&ndas

Journal article

Kumar K, Groom K, Owles H, Park M, Razak Y, Hyde T, Bloom C, Han L-Y, Wong E, Brown J, Coker R, Mak V, Elkin Set al., 2020, Linking advice line queries to education during the COVID-19 pandemic: learning together, PCRS Respiratory Conference

Conference paper

Bloom C, de Preux L, Sheikh A, Quint Jet al., 2020, Health and cost impact of stepping down asthma medication for UK patients, 2001–2017: a population-based observational study, PLoS Medicine, Vol: 17, ISSN: 1549-1277

BackgroundGuidelines recommend stepping down asthma treatment to the minimum effective dose to achieve symptom control, prevent adverse side effects, and reduce costs. Limited data exist on asthma prescription patterns in a real-world setting. We aimed to evaluate the appropriateness of doses prescribed to a UK general asthma population and assess whether stepping down medication increased exacerbations or reliever use, as well as its impact on costs.Methods and findingsWe used nationwide UK primary care medical records, 2001–2017, to identify 508,459 adult asthma patients managed with preventer medication. Prescriptions of higher-level medication: medium/high-dose inhaled corticosteroids (ICSs) or ICSs + add-on medication (long-acting β2-agonist [LABA], leukotriene receptor antagonist [LTRA], theophylline, or long-acting muscarinic antagonist [LAMA]) steadily increased over time (2001 = 49.8%, 2017 = 68.3%). Of those prescribed their first preventer, one-third were prescribed a higher-level medication, of whom half had no reliever prescription or exacerbation in the year prior. Of patients first prescribed ICSs + 1 add-on, 70.4% remained on the same medication during a mean follow-up of 6.6 years. Of those prescribed medium/high-dose ICSs as their first preventer, 13.0% already had documented diabetes, cataracts, glaucoma, or osteopenia/osteoporosis. A cohort of 125,341 patients were drawn to assess the impact of stepping down medication: mean age 50.4 years, 39.4% males, 39,881 stepped down. Exposed patients were stepped down by dropping their LABAs or another add-on or by halving their ICS dose (halving their mean-daily dose or their inhaler dose). The primary and secondary outcomes were, respectively, exacerbations and an increase in reliever prescriptions. Multivariable regression was used to assess outcomes and determine the prognostic factors for initiating stepdown. There was no increased exacerbation risk for each possible medication stepdown (ad

Journal article

Bloom C, Douglas I, Usmani OS, Quint JKet al., 2020, Inhaled corticosteroid treatment regimens and health outcomes in a UK COPD population study [Corrigendum], The International Journal of Chronic Obstructive Pulmonary Disease, Vol: 15, Pages: 869-869, ISSN: 1176-9106

Journal article

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