Christine Bucknall

Glasgow supported self-management trial (GSuST) for patients with moderate to severe COPD: randomised controlled trial

Objective To determine whether supported self management in chronic obstructive pulmonary disease (COPD) can reduce hospital readmissions in the United Kingdom. Design Randomised controlled trial. Setting Community based intervention in the west of Scotland. Participants Patients admitted to hospital with acute exacerbation of COPD. Intervention Participants in the intervention group were trained to detect and treat exacerbations promptly, with ongoing support for 12 months. Main outcome measures The primary outcome was hospital readmissions and deaths due to COPD assessed by record linkage of Scottish Morbidity Records; health related quality of life measures were secondary outcomes. Results 464 patients were randomised, stratified by age, sex, per cent predicted forced expiratory volume in 1 second, recent pulmonary rehabilitation attendance, smoking status, deprivation category of area of residence, and previous COPD admissions. No difference was found in COPD admissions or death (111/232 (48%) v 108/232 (47%); hazard ratio 1.05, 95% confidence interval 0.80 to 1.38). Return of health related quality of life questionnaires was poor (n=265; 57%), so that no useful conclusions could be made from these data. Pre-planned subgroup analysis showed no differential benefit in the primary outcome relating to disease severity or demographic variables. In an exploratory analysis, 42% (75/150) of patients in the intervention group were classified as successful self managers at study exit, from review of appropriateness of use of self management therapy. Predictors of successful self management on stepwise regression were younger age (P=0.012) and living with others (P=0.010). COPD readmissions/deaths were reduced in successful self managers compared with unsuccessful self managers (20/75 (27%) v 51/105 (49%); hazard ratio 0.44, 0.25 to 0.76; P=0.003). Conclusion Supported self management had no effect on time to first readmission or death with COPD. Exploratory subgroup analysis identified a minority of participants who learnt to self manage; this group had a significantly reduced risk of COPD readmission, were younger, and were more likely to be living with others. Trial registration Clinical trials NCT 00706303.

Bronchial hyperreactivity in patients who cough after receiving angiotensin converting enzyme inhibitors

Angiotensin converting enzyme inhibitors cause cough in some patients, but the mechanism of this effect is not known. Six patients in whom these inhibitors had caused cough and a further two patients in whom they were suspected to have caused worsening of bronchial asthma were studied. Nine patients in whom angiotensin converting enzyme inhibitors had not been associated with cough served as controls. In the controls lung function and bronchial reactivity were measured once; for the study patients these and the cough index were measured twice before rechallenge for two weeks with an angiotensin enzyme inhibitor and once afterwards. Rechallenge with drug for two weeks caused a significant decrease in the mean concentration of histamine causing a 35% fall in airways conductance and a significant increase in the cough index. Patients with cough showed bronchial hyperactivity compared with the controls, which increased after rechallenge with the inhibitors. Cough associated with converting enzyme inhibitors may be a variant of the cough in asthma.

Comorbidity in severe asthma requiring systemic corticosteroid therapy: cross-sectional data from the Optimum Patient Care Research Database and the British Thoracic Difficult Asthma Registry

Objective To determine the prevalence of systemic corticosteroid-induced morbidity in severe asthma. Design Cross-sectional observational study. Setting The primary care Optimum Patient Care Research Database and the British Thoracic Society Difficult Asthma Registry. Participants Optimum Patient Care Research Database (7195 subjects in three age- and gender-matched groups)—severe asthma (Global Initiative for Asthma (GINA) treatment step 5 with four or more prescriptions/year of oral corticosteroids, n=808), mild/moderate asthma (GINA treatment step 2/3, n=3975) and non-asthma controls (n=2412). 770 subjects with severe asthma from the British Thoracic Society Difficult Asthma Registry (442 receiving daily oral corticosteroids to maintain disease control). Main outcome measures Prevalence rates of morbidities associated with systemic steroid exposure were evaluated and reported separately for each group. Results 748/808 (93%) subjects with severe asthma had one or more condition linked to systemic corticosteroid exposure (mild/moderate asthma 3109/3975 (78%), non-asthma controls 1548/2412 (64%); p<0.001 for severe asthma versus non-asthma controls). Compared with mild/moderate asthma, morbidity rates for severe asthma were significantly higher for conditions associated with systemic steroid exposure (type II diabetes 10% vs 7%, OR=1.46 (95% CI 1.11 to 1.91), p<0.01; osteoporosis 16% vs 4%, OR=5.23, (95% CI 3.97 to 6.89), p<0.001; dyspeptic disorders (including gastric/duodenal ulceration) 65% vs 34%, OR=3.99, (95% CI 3.37 to 4.72), p<0.001; cataracts 9% vs 5%, OR=1.89, (95% CI 1.39 to 2.56), p<0.001). In the British Thoracic Society Difficult Asthma Registry similar prevalence rates were found, although, additionally, high rates of osteopenia (35%) and obstructive sleep apnoea (11%) were identified. Conclusions Oral corticosteroid-related adverse events are common in severe asthma. New treatments which reduce exposure to oral corticosteroids may reduce the prevalence of these conditions and this should be considered in cost-effectiveness analyses of these new treatments.

Obesity-associated severe asthma represents a distinct clinical phenotype: analysis of the British Thoracic Society Difficult Asthma Registry Patient cohort according to BMI.

BACKGROUND Obesity has emerged as a risk factor for the development of asthma and it may also influence asthma control and airway inflammation. However, the role of obesity in severe asthma remains unclear. Thus, our objective was to explore the association between obesity (defied by BMI) and severe asthma. METHODS Data from the British Thoracic Society Difficult Asthma Registry were used to compare patient demographics, disease characteristics, and health-care utilization among three BMI categories (normal weight: 18.5-24.99; overweight: 25-29.99; obese: 30) in a well-characterized group of adults with severe asthma. RESULTS The study population consisted of 666 patients with severe asthma; the group had a median BMI of 29.8 (interquartile range, 22.5-34.0). The obese group exhibited greater asthma medication requirements in terms of maintenance corticosteroid therapy (48.9% vs 40.4% and 34.5% in the overweight and normal-weight groups, respectively), steroid burst therapy, and short-acting b 2 -agonist use per day. Significant differences were seen with gastroesophageal reflux disease (53.9% vs 48.1% and 39.7% in the overweight and normal weight groups, respectively) and proton pump inhibitor use. Bone density scores were higher in the obese group, while pulmonary function testing revealed a reduced FVC and elevated carbon monoxide transfer coefficient. Serum IgE levels decreased with increasing BMI and the obese group was more likely to report eczema, but less likely to have a history of nasal polyps. CONCLUSIONS Patients with severe asthma display particular characteristics according to BMI that support the view that obesity-associated severe asthma may represent a distinct clinical phenotype.

The cost of treating severe refractory asthma in the UK: an economic analysis from the British Thoracic Society Difficult Asthma Registry

Severe refractory asthma poses a substantial burden in terms of healthcare costs but relatively little is known about the factors which drive these costs. This study uses data from the British Thoracic Society Difficult Asthma Registry (n=596) to estimate direct healthcare treatment costs from an National Health Service perspective and examines factors that explain variations in costs. Annual mean treatment costs among severe refractory asthma patients were £2912 (SD £2212) to £4217 (SD £2449). Significant predictors of costs were FEV1% predicted, location of care, maintenance oral corticosteroid treatment and body mass index. Treating individuals with severe refractory asthma presents a substantial cost to the health service.

Statistical Cluster Analysis of the British Thoracic Society Severe Refractory Asthma Registry: Clinical Outcomes and Phenotype Stability

Background Severe refractory asthma is a heterogeneous disease. We sought to determine statistical clusters from the British Thoracic Society Severe refractory Asthma Registry and to examine cluster-specific outcomes and stability. Methods Factor analysis and statistical cluster modelling was undertaken to determine the number of clusters and their membership (N = 349). Cluster-specific outcomes were assessed after a median follow-up of 3 years. A classifier was programmed to determine cluster stability and was validated in an independent cohort of new patients recruited to the registry (n = 245). Findings Five clusters were identified. Cluster 1 (34%) were atopic with early onset disease, cluster 2 (21%) were obese with late onset disease, cluster 3 (15%) had the least severe disease, cluster 4 (15%) were the eosinophilic with late onset disease and cluster 5 (15%) had significant fixed airflow obstruction. At follow-up, the proportion of subjects treated with oral corticosteroids increased in all groups with an increase in body mass index. Exacerbation frequency decreased significantly in clusters 1, 2 and 4 and was associated with a significant fall in the peripheral blood eosinophil count in clusters 2 and 4. Stability of cluster membership at follow-up was 52% for the whole group with stability being best in cluster 2 (71%) and worst in cluster 4 (25%). In an independent validation cohort, the classifier identified the same 5 clusters with similar patient distribution and characteristics. Interpretation Statistical cluster analysis can identify distinct phenotypes with specific outcomes. Cluster membership can be determined using a classifier, but when treatment is optimised, cluster stability is poor.

Dedicated severe asthma services improve health-care use and quality of life.

BACKGROUND Systematic assessment of severe asthma can be used to confirm the diagnosis, identify comorbidities, and address adherence to therapy. However, the prospective usefulness of this approach is yet to be established. The objective of this study was to determine whether the systematic assessment of severe asthma is associated with improved quality of life (QoL) and health-care use and, using prospective data collection, to compare relevant outcomes in patients referred with severe asthma to specialist centers across the United Kingdom. METHODS Data from the National Registry for dedicated UK Difficult Asthma Services were used to compare patient demographics, disease characteristics, and health-care use between initial assessment and a median follow-up of 286 days. RESULTS The study population consisted of 346 patients with severe asthma. At follow-up, there were significant reductions in health-care use in terms of primary care or ED visits (66.4% vs 87.8%, P < .0001) and hospital admissions (38% vs 48%, P = .0004). Although no difference was noted in terms of those requiring maintenance oral corticosteroids, there was a reduction in steroid dose (10 mg [8-20 mg] vs 15 mg [10-20 mg], P = .003), and fewer subjects required short-burst steroids (77.4% vs 90.8%, P = .01). Significant improvements were seen in QoL and control using the Asthma Quality of Life Questionnaire and the Asthma Control Questionnaire. CONCLUSIONS To our knowledge, this is the first time that a prospective study has shown that a systematic assessment at a dedicated severe asthma center is associated with improved QoL and asthma control and a reduction in health-care use and oral steroid burden.

Definition of a COPD self-management intervention: International Expert Group consensus

There is an urgent need for consensus on what defines a chronic obstructive pulmonary disease (COPD) self-management intervention. We aimed to obtain consensus regarding the conceptual definition of a COPD self-management intervention by engaging an international panel of COPD self-management experts using Delphi technique features and an additional group meeting. In each consensus round the experts were asked to provide feedback on the proposed definition and to score their level of agreement (1=totally disagree; 5=totally agree). The information provided was used to modify the definition for the next consensus round. Thematic analysis was used for free text responses and descriptive statistics were used for agreement scores. In total, 28 experts participated. The consensus round response rate varied randomly over the five rounds (ranging from 48% (n=13) to 85% (n=23)), and mean definition agreement scores increased from 3.8 (round 1) to 4.8 (round 5) with an increasing percentage of experts allocating the highest score of 5 (round 1: 14% (n=3); round 5: 83% (n=19)). In this study we reached consensus regarding a conceptual definition of what should be a COPD self-management intervention, clarifying the requisites for such an intervention. Operationalisation of this conceptual definition in the near future will be an essential next step. Consensus of a conceptual definition of what should be a COPD self-management intervention with its requisites http://ow.ly/Zfr0F

British Thoracic Society emergency oxygen audits

The British Thoracic Society (BTS) guideline for emergency oxygen use in adult patients was commissioned by the BTS and developed in conjunction with 21 other colleges and societies prior to publication in 2008. One of the specific aims of the Guideline Development Group was to audit the use of oxygen in UK hospitals before the guideline was published and at intervals afterwards.

An Observational Investigation of Dysfunctional Breathing and Breathing Control Therapy in a Problem Asthma Clinic

Objectives. Dysfunctional breathing (DB) is recognized as an associated problem in patients with asthma and may be identified by the Nijmegen questionnaire. We conducted an observational study to determine if breathing control therapy (BCT) improved Nijmegen scores or asthma-related quality of life in patients attending a problem asthma clinic. Methods. Nijmegen and Mini Asthma Quality of Life (Mini-AQLQ) questionnaires were completed. Patients with a positive Nijmegen (≥ 23, DB) were referred for BCT and progressive exercise testing (PET) to seek confirmation of dysfunctional breathing. Follow-up questionnaire data were collected at 6 months. Results. A total of 102 patients were studied. The total mean Nijmegen score was 26.4 (range 1–61). Those with a score ≥ 23 (DB group, n = 65, 64%) had significantly lower Mini-AQLQ (mean 2.83) than the non-DB group (n = 37, mean 4.12, 95% CI for difference 0.87, 1.87, p < 0.0001). There was a strong relationship between Nijmegen score and Mini-AQLQ (r = −0.63, p < 0.001) at baseline; 10 of 17 DB patients who completed PET showed inappropriate hyperventilation. Follow-up data, available for Nijmegen and Mini-AQLQ in 44 and 46 patients respectively, showed no significant change in either of these parameters. Conclusions. The strong relationship between Mini-AQLQ and Nijmegen scores and poor relationship between Nijmegen scores and PET-identified inappropriate hyperventilation suggest that a positive Nijmegen score overestimates the presence of dysfunctional breathing in patients with moderate to severe asthma. We found no evidence that a moderate intensity breathing control intervention had any impact on Nijmegen scores or asthma-related quality of life in this patient group.