Blood eosinophil count, a marker of inhaled corticosteroid effectiveness in preventing COPD exacerbations in post-hoc RCT and observational studies: systematic review and meta-analysis.

BACKGROUND: Blood eosinophil count has been proposed as a predictor of response to inhaled corticosteroid (ICS) in the prevention of acute exacerbations of COPD. An optimal threshold of blood eosinophil count for prescribing ICS has not been agreed. Doubt has been cast on the role by observational studies. The role of inhaled corticosteroids in this relationship, independent of long-acting bronchodilators, has not been examined. METHODS: We conducted a systematic review of post-hoc analyses of randomised controlled trials (RCTs) and observational studies examining three blood eosinophil thresholds and the independent role of ICS. Included studies were categorised by the form (relative or absolute count) and cut point of eosinophil threshold used. Thresholds assessed were relative eosinophil count of 2%, and absolute counts of 150 cells/µL and 300 cells/µL. Three meta-analyses of the effect of ICS use in post-hoc analyses of RCTs based on these counts were carried out. Initial analysis included all studies of ICS vs. any non-ICS regimen. Further analysis examined the effect of ICS, independent of the effect of long-acting bronchodilators. RESULTS: Sixteen studies examined the association between blood eosinophil count and response of exacerbation risk to ICS, in COPD patients. Eleven studies (25,881 patients) were post-hoc analyses of RCTs. Five studies (109,704 patients) were retrospective observational studies. The independent effect of ICS on the reduction of exacerbation risk was 20% at ≥2% blood eosinophil threshold (RR, 0.80; 95% CI, 0.74-0.85), 35% at ≥150 cells/µL blood eosinophil threshold (RR, 0.65; 0.52-0.79), and 39% at ≥300 cells/µL blood eosinophil threshold (RR, 0.61; 0.44-0.78). No association was found in four out of five observational studies. CONCLUSION: This is the first systematic review to assess, in post-hoc analyses of RCTs, the independent effect of ICS in reducing the risk of COPD exacerbation across a range of blood eosinophil thresholds. Association between ICS prescription and reduced exacerbation risk at these thresholds was confirmed. The lack of association found in the observational studies questions the relevance of these observations to a "real world" COPD population. To clarify the clinical utility of this biomarker, the association should be tested in prospective effectiveness studies.

Emergency Admissions for COPD in an Urban Population: The Role of Population and Primary Care Factors.

COPD is a major cause of emergency admissions worldwide. In many countries the majority of COPD care is provided by primary care teams. This study examined variation between primary care teams in rates of COPD admission and assessed the role of prevalence, deprivation, practice performance, and general practitioner (GP) and nurse supply on risk of COPD admission. Retrospective observational study of National Health Service admissions for COPD of patients registered with London general practices over four years (2006-2009). We sought associations using negative binomial regression between COPD admissions and population factors, practice organization and practice performance. Trends in rates of COPD admissions across London were stable between 2006 and 2009. COPD admission rates varied substantially between practices (2006/7: median 13.68/10,000 population (IQR 7.83-22.70)), with almost a 3-fold difference across the interquartile range each year. Practice characteristics varied to a similar extent. Variation in practice COPD admission rates was associated with diagnosed prevalence of COPD (Rate Ratio 2.06, 95% CI 1.84-2.3) and increasing levels of deprivation (RR 1.01, 1.006-1.01). Other practice characteristics, including GP and nurse supply, and practice performance scores were not predictive of practice level COPD admission rates, when controlling for COPD prevalence and socio-economic status. Main predictors of variation in rates of COPD admissions were prevalence of diagnosed COPD and socioeconomic status. The absence of evidence that variation in primary care services for COPD was associated with rates of COPD admission emphasizes the importance of primary prevention of COPD if COPD admission rates are to fall.

Withdrawal of Inhaled Corticosteroids from Patients with COPD; Effect on Exacerbation Frequency and Lung Function: A Systematic Review.

Background: Inhaled corticosteroid (ICS) therapy has been demonstrated to reduce the risk of COPD exacerbations. It should only be prescribed to COPD patients who are not adequately controlled by dual long-acting bronchodilator therapy and who have ≥2 exacerbations per year and a blood eosinophil count ≥300cells/µL. ICS therapy is widely prescribed outside guidelines to COPD patients, making ICS withdrawal an important consideration. This systematic review aims to provide an up-to-date analysis of the effect of ICS withdrawal on exacerbation frequency, change in lung function (FEV1) and to determine the proportion of COPD patients who resume ICS therapy following withdrawal. Methods: Randomised controlled trials (RCTs) and observational studies which compared ICS withdrawal with ICS continuation treatment were included. Cochrane Central, Web of Science, CINHAL, Embase and OVID Medline were searched. Risk of bias was assessed using the Cochrane RoB2 tool and the Newcastle-Ottawa Scale. Quality assessment of RCTs was conducted using GRADE. Meta-analysis of post-hoc analyses of RCTs of ICS withdrawal, stratified by blood eosinophil count (BEC), was undertaken. Results: Ten RCTs (6642 patients randomised) and 6 observational studies (160,029 patients) were included in the results. When ICS was withdrawn and long-acting bronchodilator therapy was maintained, there was no consistent difference in exacerbation frequency or lung function change between the ICS withdrawal and continuation trial arms. The evidence for these effects was of moderate quality. There was insufficient evidence to draw a firm conclusion on the proportion of patients who resumed ICS therapy following withdrawal (estimated range 12-93% of the participants). Discussion: Withdrawal of ICS therapy from patients with COPD is safe and feasible but should be accompanied by maintenance of bronchodilation therapy for optimal outcomes.

Global mortality and readmission rates following COPD exacerbation-related hospitalisation: a meta-analysis of 65 945 individual patients.

Background: Exacerbations of COPD (ECOPD) have a major impact on patients and healthcare systems across the world. Precise estimates of the global burden of ECOPD on mortality and hospital readmission are needed to inform policy makers and aid preventive strategies to mitigate this burden. The aims of the present study were to explore global in-hospital mortality, post-discharge mortality and hospital readmission rates after ECOPD-related hospitalisation using an individual patient data meta-analysis (IPDMA) design. Methods: A systematic review was performed identifying studies that reported in-hospital mortality, post-discharge mortality and hospital readmission rates following ECOPD-related hospitalisation. Data analyses were conducted using a one-stage random-effects meta-analysis model. This study was conducted and reported in accordance with the PRISMA-IPD statement. Results: Data of 65 945 individual patients with COPD were analysed. The pooled in-hospital mortality rate was 6.2%, pooled 30-, 90- and 365-day post-discharge mortality rates were 1.8%, 5.5% and 10.9%, respectively, and pooled 30-, 90- and 365-day hospital readmission rates were 7.1%, 12.6% and 32.1%, respectively, with noticeable variability between studies and countries. Strongest predictors of mortality and hospital readmission included noninvasive mechanical ventilation and a history of two or more ECOPD-related hospitalisations <12 months prior to the index event. Conclusions: This IPDMA stresses the poor outcomes and high heterogeneity of ECOPD-related hospitalisation across the world. Whilst global standardisation of the management and follow-up of ECOPD-related hospitalisation should be at the heart of future implementation research, policy makers should focus on reimbursing evidence-based therapies that decrease (recurrent) ECOPD.

Withdrawal of inhaled corticosteroids from patients with COPD with mild or moderate airflow limitation in primary care: a feasibility randomised trial.

BACKGROUND: Inhaled corticosteroids (ICS) are frequently prescribed outside guidelines to patients with chronic obstructive pulmonary disease (COPD) with mild/moderate airflow limitation and low exacerbation risk. This primary care trial explored the feasibility of identifying patients with mild/moderate COPD taking ICS, and the acceptability of ICS withdrawal. METHODS: Open feasibility trial. Outcome measures included prevalence of suitable participants, feasibility of their identification, their willingness-to-accept open randomisation to ICS withdrawal or continuation over 6 months follow-up. RESULTS: 392 (13%) of 2967 patients with COPD from 20 practices (209 618 population) identified as eligible for ICS withdrawal by electronic search algorithm. After individual patient record review, 243 (62%) were excluded because of: severe airflow limitation (65, 17%); one or more severe or two or more moderate COPD exacerbations in the previous year (86, 22%); asthma (15, 4%); and severe comorbidities (77, 20%). After exclusion, 149 patients with COPD were invited to participate and 61 agreed to randomisation. At clinical assessment, 10 patients exhibited undocumented airflow reversibility (forced expiratory volume in 1 s (FEV1) reversibility >12% and >200 mL); 2 had suffered two or more undocumented, moderate exacerbations in the previous year; 7 had severe airflow limitation; and 2 had normal spirometry. Finally, 40 were randomised. One patient died and one was lost to follow-up. 18 (45%) of the 38 (10 withdrawal and 8 usual care) exhibited previously undocumented FEV1 variability suggestive of asthma, supported in the withdrawal group by significant associations with elevated fractional exhaled nitric oxide (p=0.04), elevated symptom score (p=0.04), poorer quality of life (p=0.04) and atopic status (p=0.01). CONCLUSIONS: Identifying primary care patients with mild/moderate COPD suitable for ICS withdrawal is feasible but requires real-time verification because of unreliable recording of exacerbations and lung function. Suitable patients accepted randomisation to ICS withdrawal or continuation for the purposes of future studies. Follow-up compliance was high. Nearly 50% of participants with a diagnosis of mild/moderate COPD demonstrated previously undocumented FEV1 variability during follow-up, mandating monitoring for at least 6 months following withdrawal to exclude undiagnosed asthma.

Inhaled Corticosteroids Prescribed for COPD Patients with Mild or Moderate Airflow Limitation: Who Warrants a Trial of Withdrawal?

COPD patients prescribed inhaled corticosteroids (ICS) outside guidelines should be targeted for ICS withdrawal. Within a primary care population of 209,618 we used a combination of digital search algorithm, individual record review, and clinical review to identify COPD patients suitable for a trial of ICS withdrawal. At most, 39% of COPD patients with mild or moderate airflow limitation prescribed ICS were suitable for withdrawal according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. Recurrent exacerbations and reversible airway obstruction were the main reasons for patients' unsuitability for withdrawal. Identifying COPD patients in whom ICS withdrawal should be considered presents a challenge to primary care clinicians.

Hospital readmissions for COPD: a retrospective longitudinal study.

Prevention of chronic obstructive pulmonary disease hospital readmissions is an international priority aimed to slow disease progression and limit costs. Evidence of the risk of readmission and of interventions that might prevent it is lacking. We aimed to determine readmission risk for chronic obstructive pulmonary disease, factors influencing that risk, and variation in readmission risk between hospitals across 7.5 million people in London. This retrospective longitudinal observational study included all chronic obstructive pulmonary disease admissions to any hospital in the United Kingdom among patients registered at London general practices who had emergency National Health Service chronic obstructive pulmonary disease hospital admissions between April 2006 and March 2010. Influence of patient characteristics, geographical deprivation score, length of stay, day of week of admission or of discharge, and admitting hospital, were assessed using multiple logistic regression. 38,894 chronic obstructive pulmonary disease admissions of 20,932 patients aged ≥ 45 years registered with London general practices were recorded. 6295 patients (32.2%) had at least one chronic obstructive pulmonary disease readmission within 1 year. 1993 patients (10.2%) were readmitted within 30 days and 3471 patients (17.8%) were readmitted within 90 days. Age and patient geographical deprivation score were very weak predictors of readmission. Rates of chronic obstructive pulmonary disease readmissions within 30 days and within 90 days did not vary among the majority of hospitals. The finding of lower chronic obstructive pulmonary disease readmission rates than was previously estimated and the limited variation in these rates between hospitals suggests that the opportunity to reduce chronic obstructive pulmonary disease readmission risk is small. CHRONIC LUNG DISEASE: LOWER RISK OF READMISSION FOR LONDON-BASED PATIENTS: A managed reduction of hospital readmissions for London-based chronic lung disease patients may not be needed. Preventing hospital readmissions for patients with chronic obstructive pulmonary disease (COPD) is a key priority to improve patient care and limit costs. However, few data are available to determine and ultimately reduce the risk of readmission. Timothy Harries at King's College, London, and co-workers conducted a longitudinal study incorporating all COPD admissions into UK hospitals for 20,932 patients registered at London general practitioners between 2006 and 2010. They found that 32% of patients were readmitted within a year, 17.8% within 90 days and 10% within 30 days. Neither age nor geographical deprivation were useful predictors of readmission. These represent lower than estimated levels of readmission, suggesting there may be fewer opportunities to reduce the risk of readmission further.

Does COPD risk vary by ethnicity? A retrospective cross-sectional study.

BACKGROUND: Lower risk of COPD has been reported in black and Asian people, raising questions of poorer recognition or reduced susceptibility. We assessed prevalence and severity of COPD in ethnic groups, controlling for smoking. METHOD: A retrospective cross-sectional study using routinely collected primary care data in London. COPD prevalence, severity (% predicted forced expiratory volume in 1 second [FEV1]), smoking status, and treatment were compared between ethnic groups, adjusting for age, sex, smoking, deprivation, and practice clustering. RESULTS: Among 358,614 patients in 47 general practices, 47.6% were white, 20% black, and 5% Asian. Prevalence of COPD was 1.01% overall, 1.55% in whites, 0.58% in blacks, and 0.78% in Asians. COPD was less likely in blacks (adjusted odds ratio [OR], 0.44; 95% confidence interval [CI] 0.39-0.51) and Asians (0.82; CI, 0.68-0.98) than whites. Black COPD patients were less likely to be current smokers (OR, 0.56; CI, 0.44-0.71) and more likely to be never-smokers (OR, 4.9; CI, 3.4-7.1). Treatment of patients with similar disease severity was similar irrespective of ethnic origin, except that long-acting muscarinic antagonists were prescribed less in black COPD patients (OR, 0.53; CI, 0.42-0.68). Black ethnicity was a predictor of poorer lung function (% predicted FEV1: B coefficient, -7.6; P<0.0001), an effect not seen when ethnic-specific predicted FEV1 values were used. CONCLUSION: Black people in London were half as likely as whites to have COPD after adjusting for lower smoking rates in blacks. It seems likely that the differences observed were due either to ethnic differences in the way cigarettes were smoked or to ethnic differences in susceptibility to COPD.

Length of stay of COPD hospital admissions between 2006 and 2010: a retrospective longitudinal study.

BACKGROUND: Hospitalizations for COPD are associated with poor patient prognosis. Length of stay (LOS) of COPD admissions in a large urban area and patient and hospital factors associated with it are described. METHODS: Retrospective longitudinal study. All COPD patients registered with London general practitioners and admitted as an emergency with COPD (2006-2010), not having been admitted with COPD in the preceding 12 months were included. Association of patient and hospital characteristics with mean LOS of COPD admissions was assessed. Association between hospital and LOS was determined by negative binomial regression. RESULTS: The total number of admissions was 38,504, from 22,462 patients. The mean LOS for first admissions fell by 0.8 days (95% confidence interval [CI]: 0.7-1.5) from 8.2 to 7.0 days between 2006 and 2010. Seventy-nine percent of first admissions were ≤10 days, with a mean LOS of 3.7 days (2009-2010). The mean LOS of successive COPD admissions of the same patients was the same or less throughout the study period. The interval between successive admissions fell from a mean of 357 days between the first and second admission to a mean of 19 days after eight admissions. Age accounted for 2.3% of the variance in LOS. Socioeconomic deprivation did not predict LOS. Fewer discharges happened at the weekend (1,893/day) than on weekdays (5,218/day). The mean LOS varied between hospitals, from 4.9 days (95% CI: 3.8-5.9) to 9.5 days (95% CI: 8.6-10.3) when adjusting for clustering, age, sex, and socioeconomic deprivation. CONCLUSION: The fall in LOS of the first COPD admission between 2006 and 2010 reflects international trends. The stability of LOS in successive admissions suggests that increasing severity of disease does not affect recovery time from an exacerbation. Variations between hospitals of nearly 5 days in LOS for COPD admissions suggests that significant improvements in patient outcomes and in savings in health care utilization could be made in hospitals with longer LOS.

Chronic obstructive pulmonary disease hospital admissions and drugs--unexpected positive associations: a retrospective general practice cohort study.

BACKGROUND: Increased prescribing of inhaled long-acting anti-muscarinic (LAMA) and combined inhaled long-acting ß2-agonist and corticosteroid (LABA+ICS) drugs for the treatment of chronic obstructive pulmonary disease (COPD) has led to hopes of reduced hospital admissions from this disease. AIMS: To investigate the impact of rising primary care prescribing of LAMA and LABA+ICS drugs on COPD admissions. METHODS: This retrospective cohort study of general practice COPD admission and prescribing data between 2007 and 2010 comprised a representative group of 806 English general practices (population 5,264,506). Outcome measures were practice rates of COPD patient admissions and prescription costs of LAMA and LABA+ICS. General practice characteristics were based on the UK quality and outcomes framework. RESULTS: Rates of COPD admissions remained stable from 2001 to 2010. Practice-prescribing volumes of LAMA per practice patient and LABA+ICS per practice patient increased by 61 and 26%, respectively, between 2007 and 2010. Correlation between costs of LAMA and those of LABA+ICS increased year on year, and was the highest in 2010 (Pearson's r=0.68; 95% confidence interval (CI) 0.64 to 0.72). Practice COPD admission rates were positively predicted by practice-prescribing volumes of LAMA (2010: B=1.23, 95% CI 0.61 to 1.85) and of LABA+ICS (2010: B=0.32, 95% CI 0.12 to 0.52) when controlling for practice list size, COPD prevalence and deprivation. CONCLUSION: The increase in the prescribing of LAMA and LABA+ICS inhalers was not associated with the predicted fall in hospital admission rates for COPD patients. The positive correlation between high practice COPD prescribing and high practice COPD admissions was not explained.