Previous tuberculosis disease as a risk factor for chronic obstructive pulmonary disease: a cross-sectional analysis of multicountry, population-based studies.

BACKGROUND: Risk factors for COPD in high-income settings are well understood; however, less attention has been paid to contributors of COPD in low-income and middle-income countries (LMICs) such as pulmonary tuberculosis. We sought to study the association between previous tuberculosis disease and COPD by using pooled population-based cross-sectional data in 13 geographically diverse, low-resource settings. METHODS: We pooled six cohorts in 13 different LMIC settings, 6 countries and 3 continents to study the relationship between self-reported previous tuberculosis disease and lung function outcomes including COPD (defined as a postbronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) below the lower limit of normal). Multivariable regressions with random effects were used to examine the association between previous tuberculosis disease and lung function outcomes. RESULTS: We analysed data for 12 396 participants (median age 54.0 years, 51.5% male); 332 (2.7%) of the participants had previous tuberculosis disease. Overall prevalence of COPD was 8.8% (range 1.7%-15.5% across sites). COPD was four times more common among those with previous tuberculosis disease (25.7% vs 8.3% without previous tuberculosis disease, p<0.001). The adjusted odds of having COPD was 3.78 times higher (95% CI 2.87 to 4.98) for participants with previous tuberculosis disease than those without a history of tuberculosis disease. The attributable fraction of COPD due to previous tuberculosis disease in the study sample was 6.9% (95% CI 4.8% to 9.6%). Participants with previous tuberculosis disease also had lower prebronchodilator Z-scores for FEV1 (-0.70, 95% CI -0.84 to -0.55), FVC (-0.44, 95% CI -0.59 to -0.29) and the FEV1:FVC ratio (-0.63, 95% CI -0.76 to -0.51) when compared with those without previous tuberculosis disease. CONCLUSIONS: Previous tuberculosis disease is a significant and under-recognised risk factor for COPD and poor lung function in LMICs. Better tuberculosis control will also likely reduce the global burden of COPD.

"Life-changing": the experience of super-responders to biologics in severe asthma.

BACKGROUND: There is limited information on the patient's perspective of how biologic treatments impact their lives. We conducted a qualitative study to explore the patient's experience of being considered a super-responder from a quality of life perspective. METHODS: Patients with severe asthma identified as super-responders were invited to semi-structured interviews conducted online. Participants could bring a family member/friend to the interview. The interviews explored experiences of biologic treatment, were transcribed and underwent thematic analysis. RESULTS: Twenty-five participants took part in this study. Themes emerged on the impact of biologic treatment for participants and for their friends/family: (i) Words used to describe their often life-changing experiences and (ii) the positive changes noted. Biologic treatment stopped the disruption of family life and social life caused by exacerbations. Improvements in mental health were also noted. Marked individual variations in the way it affected their lives were noted. Most participants noticed improvements 2-3 months after starting their biologic, but some noticed improvement within a few days and others after 6 months. CONCLUSIONS: Super-responders reported profound but heterogeneous improvements following biologic treatment beyond asthma symptoms and exacerbations including important benefits to social and family life. Improvements may be underestimated as social and family benefits are not reliably measured in current studies with implications for health economic evaluations. Not all patients are super-responders, and excellent responses may be lost in group mean data in trials. Individual time course and response patterns need further elucidation to identify who will respond best to biologics.

Preliminary development of a questionnaire to measure the extra-pulmonary symptoms of severe asthma.

BACKGROUND: Research into the effects of asthma treatments on the extra-pulmonary symptoms of severe asthma is limited by the absence of a suitable questionnaire. The aim was to create a questionnaire suitable for intervention studies by selecting symptoms that are statistically associated with asthma pathology and therefore may improve when pathology is reduced. METHODS: Patients attending a specialist asthma clinic completed the 65-item General Symptom Questionnaire (GSQ-65), a questionnaire validated for assessing symptoms of people with multiple medically unexplained symptoms. Lung function (FEV1%) and cumulative oral corticosteroids (OCS) calculated from maintenance dose plus exacerbations were obtained from clinic records. Pathology was represented by the two components of a principal component analysis (PCA) of FEV1% and OCS. LASSO regression was used to select symptoms that had high coefficients with these two principal components and occurred frequently in severe asthma. RESULTS: 100 patients provided data. PCA revealed two components, one where FEV1% and OCS were inversely related and another where they were directly related. LASSO regression revealed 39 symptoms with non-zero coefficients on one or more of the two principal components from which 16 symptoms were selected for the GSQ-A on the basis of magnitude of coefficient and frequency. Asthma symptoms measured by asthma control questionnaires were excluded. The GSQ-A correlated 0.33 and - 0.34 (p = 0.001) with the two principal components. CONCLUSION: The GSQ-A assesses the frequency of 16 heterogenous non-respiratory symptoms that are associated with asthma severity using the statistical combination of FEV1% and OCS.

Comparison of the sensitivity of patient-reported outcomes for detecting the benefit of biologics in severe asthma.

BackgroundThe sensitivity of patient-reported outcomes (PROs) to detect the effects of treatment change depends on the match between the change in items of the PRO and the change that takes place in a sample of people. The aim of this study is to compare the sensitivity of different PROs in detecting changes following the initiation of biologic treatment in asthma. Methods: Patients starting a biologic treatment as part of clinical care completed the Asthma Control Questionnaire (ACQ-6), the Severe Asthma Questionnaire (SAQ and SAQ-global scores) and the EQ5D (EQ-5D-5L and EQ5D-VAS) at baseline. They completed the ACQ-6, SAQ, SAQ-global and a retrospective global rating of change (GRoC) scale at weeks 4, 8 and 16 and completed the EQ-5D-5L and EQ5D-VAS at week 16. The SAQ-global and EQ5D-VAS differ but both are single item 100-point questions. Sensitivity was measured by Cohen's D effect size at each of the three time points. Results: 110 patients were recruited. Depending on the time of assessment, effect size varied between 0.45 and 0.64 for the SAQ, between 0.50 and 0.77 for the SAQ-global; between 0.45 and 0.69 for ACQ-6; between 0.91 and 1.22 for GRoC; 0.32 for EQ-5D-5L and 0.49 for EQ5D-VAS. Conclusion: The sensitivity to change of a questionnaire varies with the time of measurement. The three asthma-specific prospective measures (SAQ, SAQ-global and ACQ-6) have similar sensitivity to change. The single-item EQ5D-VAS was less sensitive than the asthma specific measures and less sensitive than the single-item SAQ-global. The EQ-5D-5L was least sensitive.

Validation of subscales of the Severe Asthma Questionnaire (SAQ) using exploratory factor analysis (EFA).

BACKGROUND: The Severe Asthma Questionnaire (SAQ) is a health related quality of life (HRQoL) questionnaire validated for use in severe asthma. It is scored using the mean value of 16 items (SAQ score) in addition to a single item global rating of HRQoL (SAQ-global). The aim was to validate clinically relevant subscales using exploratory factor analysis (EFA). METHODS: The SAQ was completed, along with measures of asthma control and EQ5D-5L by patients attending six UK severe asthma centres. Clinical data were included in the analysis. EFA using principal axis factoring and oblimin rotation was used to achieve simple structure of data. RESULTS: 460 patients with severe asthma participated, 65% women, mean age 51 (16-83) years. A three factor solution achieved best fit and showed that the SAQ items formed three distinct but inter-correlated groups of items where items were grouped in a way that was consistent with item content. The three subscales were differentially associated with clinically relevant variables (lung function and mood). Males and females interpreted the question of night disturbance in different ways. CONCLUSIONS: This paper provides a template for best practice in the use of EFA when validating HRQoL subscales. The SAQ can be scored as three subscales with content reflecting three different constructs people with severe asthma use when making judgements about their lives. The subscale 'My Life' assesses the impact of severe asthma on different life activities, 'My Mind' assesses the perceived emotional impact and 'My Body' the impact of extra-pulmonary symptoms and side effects.

The construction and validation of the Severe Asthma Questionnaire.

The US Food and Drug Administration's procedure for scale validation requires a documented stepwise process of qualitative and quantitative data. The aim of this paper is to provide final quantitative validating data for the Severe Asthma Questionnaire (SAQ).The SAQ, Asthma Control Test, Mini Asthma Quality of Life Questionnaire and EQ-5D-5L were completed by 160 patients attending a severe asthma clinic; 51 patients completed the SAQ on two occasions for test-retest reliability analysis. The SAQ produces two scores, a SAQ score based on the average of 16 items and a SAQ-global score from a single 100-point global quality of life scale.Construct validity was demonstrated by factor analysis of the 16 items, convergent validity by correlations of >0.6 between the SAQ, SAQ-global and other questionnaires, and discriminant validity by the ability of the SAQ and SAQ-global to distinguish between different treatment levels. Test-retest reliability (intra-class correlation) was 0.93 for the SAQ and 0.93 for the SAQ-global, and the alpha coefficient for the SAQ was 0.93.The SAQ was developed using recommended qualitative and quantitative procedures for scale development, and can be used to gain insight into patients' perceptions of how severe asthma and its treatment affects their lives.

How patient participation was used to develop a questionnaire that is fit for purpose for assessing quality of life in severe asthma.

BACKGROUND: Previous research shows that existing asthma quality of life questionnaires fail to measure the burden of oral corticosteroids that can be used to treat severe asthma, and are therefore not fit for purpose for severe asthma according to the USA's Federal Drug Authority's (FDA) criteria for content validity. Patient input and documentation of that input is key to achieving content validity according to FDA guidelines. This paper describes the process of constructing a new questionnaire to measure the burden of asthma symptoms and burden of treatment in severe asthma, using criteria specified by the FDA. METHODS: A draft severe asthma questionnaire (SAQ) was constructed using qualitative input from severe asthma patients who took part in an earlier study. The aim of this study was to improve that draft questionnaire using a further group of patients. In four iterative focus groups, 16 people with severe asthma completed the draft questionnaire, discussed the wording and structure and suggested changes that were incorporated into the final version. RESULTS: The original intention to ask patients to identify whether problems were caused by asthma symptoms or side effects of medication was abandoned as the attribution of cause was found to be difficult and inconsistent. The recall period of 2 weeks was acceptable but fails to reflect the patients' desire to express the variability of severe asthma. Patients suggested improvements to the wording of the draft questionnaire, including splitting some items in two, combining two items in one, and changes to some of the words in individual items and the response scale. CONCLUSIONS: The final version of the questionnaire was substantially different from one constructed using only qualitative reports from patients about the quality of life deficits of severe asthma. Patients make a valuable contribution to the questionnaire if they are asked to comment and improve an initial draft and where patients are treated as partners in the process of questionnaire construction, rather than only as a source of information to experts who construct the questionnaire.

Posttraumatic Stress Disorder Among Older Patients with Chronic Obstructive Pulmonary Disease.

This study explored (1) the incidence of posttraumatic stress disorder (PTSD) resulting from past trauma among older patients with COPD and (2) whether PTSD and COPD severity would relate to psychiatric co-morbidity and health-related quality of life. Eighty-five older patients completed the Hospital Anxiety and Depression Scale, the Chronic Respiratory Questionnaire, the Posttraumatic Stress Diagnostic Scale and the Medical Outcomes Short Form 12. The results showed that 55, 39 and 6 % had no, partial and full-PTSD respectively. Partial least squares showed that PTSD was significantly correlated with COPD severity which in turn was significantly correlated with health-related quality of life and psychiatric co-morbidity. Mediational analysis showed that the emotional symptoms of COPD mediated between PTSD and the mental health functioning of health-related quality of life and between PTSD and depression. To conclude, PTSD from past trauma was related to the severity of COPD for older patients. In particular, it impacted on the elevated emotional arousal of COPD severity. In turn, COPD severity impacted on older patients' general psychological well-being and depression.

A qualitative study of the impact of severe asthma and its treatment showing that treatment burden is neglected in existing asthma assessment scales.

BACKGROUND: People with severe asthma experience significant respiratory symptoms and suffer adverse effects of oral corticosteroids (OCS), including disturbed mood and physical symptoms. OCS impacts on health-related quality of life (HRQoL) have not been quantified. Asthma HRQoL scales are valid as outcome measures for patients requiring OCS only if they assess the deficits imposed by OCS. AIMS: The aim of this study was to compare the burden of disease and treatment in patients with severe asthma with items in eight asthma-specific HRQoL scales. METHODS: Twenty-three patients with severe asthma recruited from a severe asthma clinic were interviewed about the impact of their respiratory symptoms and the burden of their treatment. The domains from a thematic analysis of these interviews were compared with the items of eight asthma-specific HRQoL scales. RESULTS: In addition to the burden caused by symptoms, ten domains of OCS impact on HRQoL were identified: depression, irritability, sleep, hunger, weight, skin, gastric, pain, disease anxiety, and medication anxiety. Some patients experienced substantial HRQoL deficits attributed to OCS. Although all HRQoL scales include some OCS-relevant items, all eight scales fail to adequately assess the several types of burden experienced by some patients while on OCS. CONCLUSION: The burden of OCS in severe asthma is neglected in policy and practice because it is not assessed in outcome studies. Existing asthma HRQoL scales provide an overly positive estimation of HRQoL in patients with frequent exposure to OCS and underestimate the benefit of interventions that reduce OCS exposure. Changes to existing measurement procedures are needed.

Effect of Stepping Up to High-Dose Inhaled Corticosteroids in Patients With Asthma: UK Database Study.

BACKGROUND: It is unclear whether patients with asthma benefit from stepping up to high-dose inhaled corticosteroids (ICSs). OBJECTIVE: To determine the effectiveness of stepping up to high-dose ICSs. METHODS: A historic cohort study of patients with asthma (≥13 years old), identified from 2 large UK electronic medical record databases, was conducted. Patients who remained on medium-dose ICSs were compared with those who stepped up from medium- to high-dose ICSs, whereas patients who stepped up from low- to medium-dose ICSs were compared with those who stepped up from low- to high-dose ICSs. Time to first severe exacerbation (primary outcome) between treatment groups was compared using multivariable Cox proportional hazards models, and the number of exacerbations and antibiotics courses was analyzed using negative binomial regression. Inverse probability of treatment weighting was used to handle confounding. RESULTS: The mean follow-up time to first exacerbation was 2.7 ± 2.7 years for those who remained on stable medium-dose ICSs and 2.0 ± 2.2 years for those who stepped up from medium- to high-dose ICSs. A similar pattern was noted for those who stepped up from low- to medium-dose ICSs (2.6 ± 2.5 years) and from low- to high-dose ICSs (2.3 ± 2.5 years). Patients who stepped up from medium- to high-dose ICSs (n = 6879) had a higher risk of exacerbations during follow-up compared with those who remained on medium-dose ICSs (n = 51,737; hazard ratio, 1.17; 95% CI, 1.12-1.22). This was similar in patients stepping up from low- to high-dose (n = 3232) compared with low- to medium-dose (n = 12,659) ICSs (hazard ratio, 1.10; 95% CI, 1.04-1.17). A step-up to high-dose ICSs was also associated with a higher number of asthma exacerbations and antibiotics courses. No significant difference in associations was found across subgroups of patients with different blood eosinophil counts. CONCLUSIONS: We found no evidence that a step-up to high-dose ICSs is effective in preventing future asthma exacerbations.

Impact of Initiating Biologics in Patients With Severe Asthma on Long-Term Oral Corticosteroids or Frequent Rescue Steroids (GLITTER): Data From the International Severe Asthma Registry.

BACKGROUND: Effectiveness of biologics has neither been established in patients with high oral corticosteroid exposure (HOCS) nor been compared with effectiveness of continuing with HOCS alone. OBJECTIVE: To examine the effectiveness of initiating biologics in a large, real-world cohort of adult patients with severe asthma and HOCS. METHODS: This was a propensity score-matched, prospective cohort study using data from the International Severe Asthma Registry. Between January 2015 and February 2021, patients with severe asthma and HOCS (long-term OCSs for ≥1 year or ≥4 courses of rescue OCSs within a 12-month period) were identified. Biologic initiators were identified and, using propensity scores, matched 1:1 with noninitiators. The impact of biologic initiation on asthma outcomes was assessed using generalized linear models. RESULTS: We identified 996 matched pairs of patients. Both groups improved over the 12-month follow-up period, but improvement was greater for biologic initiators. Biologic initiation was associated with a 72.9% reduction in the average number of exacerbations per year versus noninitiators (0.64 vs 2.06; rate ratio, 0.27 [95% CI, 0.10-0.71]). Biologic initiators were 2.2 times more likely than noninitiators to take a daily long-term OCS dose of less than 5 mg (risk probability, 49.6% vs 22.5%; P = .002) and had a lower risk of asthma-related emergency department visits (relative risk, 0.35 [95% CI, 0.21-0.58]; rate ratio, 0.26 [0.14-0.48]) and hospitalizations (relative risk, 0.31 [95% CI, 0.18-0.52]; rate ratio, 0.25 [0.13-0.48]). CONCLUSIONS: In a real-world setting, including patients with severe asthma and HOCS from 19 countries, and within an environment of clinical improvement, initiation of biologics was associated with further improvements across multiple asthma outcomes, including exacerbation rate, OCS exposure, and health care resource utilization.

Characterization of Patients in the International Severe Asthma Registry with High Steroid Exposure Who Did or Did Not Initiate Biologic Therapy.

Background: Many severe asthma patients with high oral corticosteroid exposure (HOCS) often do not initiate biologics despite being eligible. This study aimed to compare the characteristics of severe asthma patients with HOCS who did and did not initiate biologics. Methods: Baseline characteristics of patients with HOCS (long-term maintenance OCS therapy for at least 1 year, or ≥4 courses of steroid bursts in a year) from the International Severe Asthma Registry (ISAR; https://isaregistries.org/), who initiated or did not initiate biologics (anti-lgE, anti-IL5/5R or anti-IL4R), were described at the time of biologic initiation or registry enrolment. Statistical relationships were tested using Pearson's chi-squared tests for categorical variables, and t-tests for continuous variables, adjusting for potential errors in multiple comparisons. Results: Between January 2015 and February 2021, we identified 1412 adult patients with severe asthma from 19 countries that met our inclusion criteria of HOCS, of whom 996 (70.5%) initiated a biologic and 416 (29.5%) did not. The frequency of biologic initiation varied across geographical regions. Those who initiated a biologic were more likely to have higher blood eosinophil count (483 vs 399 cells/µL, p=0.003), serious infections (49.0% vs 13.3%, p<0.001), nasal polyps (35.2% vs 23.6%, p<0.001), airflow limitation (56.8% vs 51.8%, p=0.013), and uncontrolled asthma (80.8% vs 73.2%, p=0.004) despite greater conventional treatment adherence than those who did not start a biologic. Both groups had similar annual asthma exacerbation rates in the previous 12 months (5.7 vs 5.3, p=0.147). Conclusion: Around one third of severe HOCS asthma patients did not receive biologics despite a similar high burden of asthma exacerbations as those who initiated a biologic therapy. Other disease characteristics such as eosinophilic phenotype, serious infectious events, nasal polyps, airflow limitation and lack of asthma control appear to dictate biologic use.

A pilot study of identification and case management of high-risk COPD patients in a general practice.

BACKGROUND: A variety of individual therapeutic interventions have been shown to reduce hospital admissions and improve quality of life in patients with chronic obstructive pulmonary disease (COPD). However, there is a paucity of data of looking at the effect of case management in primary care (i.e. using an integrated care approach) of people at higher risk of mortality from COPD. OBJECTIVE: To examine the effect of case management in primary care of patients with COPD at high risk of hospital admission, identified using a novel multidimensional index of disease severity (DOSE index). METHODS: Observational pilot study in a single general practice. High-risk patients were identified using the DOSE index and case managed using an IT system according to British National Guidelines over a 6-month period. RESULTS: Eleven patients entered and completed the study. There was no improvement in health status, but there was a non-significant reduction in total hospital admissions (three versus zero) and total bed days (16 versus 0) compared to the same reference period in the previous year. There was an increase in self-management knowledge. CONCLUSIONS: Case management of high-risk patients in primary care may reduce hospital admissions. This needs to be tested in a randomized controlled trial.

Derivation and validation of a composite index of severity in chronic obstructive pulmonary disease: the DOSE Index.

RATIONALE: Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a multicomponent disease with systemic consequences and effects on quality of life. Single measures such as lung function provide a limited reflection of how the disease affects patients. Composite measures have the potential to account for many of the facets of COPD. OBJECTIVES: To derive and validate a multicomponent assessment tool of COPD severity that is applicable to all patients and health care settings. METHODS: The index was derived using data from 375 patients with COPD in primary care. Regression analysis led to a model explaining 48% of the variance in health status as measured by the Clinical COPD Questionnaire with four components: dyspnea (D), airflow obstruction (O), smoking status (S), and exacerbation frequency (E). The DOSE Index was validated in cross-sectional and longitudinal samples in various health care settings in Holland, Japan, and the United Kingdom. MEASUREMENTS AND MAIN RESULTS: The DOSE Index correlated with health status in all data sets. A high DOSE Index score (> or = 4) was associated with a greater risk of hospital admission (odds ratio, 8.3 [4.1-17]) or respiratory failure (odds ratio, 7.8 [3.4-18.3]). The index predicted exacerbations in the subsequent year (P < or = 0.014). CONCLUSIONS: The DOSE Index is a simple, valid tool for assessing the severity of COPD. The index is related to a range of clinically important outcomes such as health care consumption and predicts future events.

Comparison of the effects of pulmonary and extra-pulmonary symptoms on health-related quality of life in patients with severe asthma.

OBJECTIVES: To survey the frequency of extra-pulmonary symptoms reported by a sample of patients with severe asthma, their contribution to quality of life and relationship to treatment pathways. METHODS: Consenting patients (N = 100) attending a severe asthma clinic completed questionnaire measures of extra-pulmonary symptoms (the General symptom Questionnaire, GSQ), pulmonary symptoms (Asthma Control Test, ACT), quality of life (the Severe Asthma Questionnaire, SAQ) and health status (EQ-5D-5L). RESULTS: A median of 21 extra-pulmonary symptoms were reported per week. GSQ correlated -0.65 with the ACT and 0.69 with the SAQ. Linear regression showed that both the ACT and GSQ were significant predictors of SAQ mean score, p < 0.001. In patients not receiving biologics, those with high cumulative OCS exposure (≥1120 mg per year) had significantly worse scores (p < 0.05) on all questionnaires except the ACT and GSQ compared to those with low cumulative OCS exposure. DISCUSSION: Extra-pulmonary symptoms were common in this sample of people with severe asthma. Extra-pulmonary and pulmonary symptoms contribute equal variance to the score of HRQoL, showing that they are equally important contributors to patients' experience of severe asthma. Extra-pulmonary symptoms are often overlooked in clinical medicine and in measures of quality of life. Participants receiving biologic treatments had lower extra-pulmonary symptoms possibly indicating that biologics reduce systemic symptoms more effectively than other treatments.

Characterization of Severe Asthma Worldwide: Data From the International Severe Asthma Registry.

BACKGROUND: Clinical characteristics of the international population with severe asthma are unknown. Intercountry comparisons are hindered by variable data collection within regional and national severe asthma registries. We aimed to describe demographic and clinical characteristics of patients treated in severe asthma services in the United States, Europe, and the Asia-Pacific region. METHODS: The International Severe Asthma Registry retrospectively and prospectively collected data in patients with severe asthma (≥ 18 years old), receiving Global Initiative for Asthma (GINA) Step 5 treatment or with severe asthma remaining uncontrolled at GINA Step 4. Baseline demographic and clinical data were collected from the United States, United Kingdom, South Korea, Italy, and the Severe Asthma Web-based Database registry (including Australia, Singapore, and New Zealand) from December 2014 to December 2017. RESULTS: We included 4,990 patients. Mean (SD) age was 55.0 (15.9) years, and mean (SD) age at asthma onset was 30.7 (17.7) years. Patients were predominantly female (59.3%) and white (72.6%), had never smoked (60.5%), and were overweight or obese (70.4%); 34.9% were at GINA Step 5; and 57.2% had poorly controlled disease. A total of 51.1% of patients were receiving regular intermittent oral corticosteroids, and 25.4% were receiving biologics (72.6% for those at GINA Step 5). Mean (SD) exacerbation rate was 1.7 (2.7) per year. Intercountry variation was observed in clinical characteristics, prescribed treatments, and biomarker profiles. CONCLUSIONS: Using a common data set and definitions, this study describes severe asthma characteristics of a large patient cohort included in multiple severe asthma registries and identifies country differences. Whether these are related to underlying epidemiological factors, environmental factors, phenotypes, asthma management systems, treatment access, and/or cultural factors requires further study.

Spirometry in primary care case-identification, diagnosis and management of COPD.

Chronic obstructive pulmonary disease (COPD) is an important cause of morbidity and mortality worldwide, yet it remains significantly under-diagnosed. Systematic and opportunistic case-identification efforts in primary care, using questionnaires, careful assessment to identify symptoms, and follow-up spirometry, might improve diagnosis rates and enable earlier detection and management of COPD. The aims of spirometry performed for case-identification purposes are to exclude those patients with symptoms but normal lung function and identify those who require more complete investigation for COPD, including 'diagnostic standard' spirometry. Among patients with a confirmed diagnosis of COPD, spirometry monitoring is useful in identifying those with rapid deterioration in lung function who require further assessment. Spirometry in primary care can also support patient education and may encourage smoking cessation and treatment adherence.

Evidence for similarity in symptoms and mechanism: The extra-pulmonary symptoms of severe asthma and the polysymptomatic presentation of fibromyalgia.

BACKGROUND: Asthma is a disease of the lung and a systemic disease. Functional disorders are associated with multiple systemic abnormalities that have been explained by complexity models. The aim was to test the similarity in type and aetiology between the extra-pulmonary symptoms of severe asthma and the symptoms of fibromyalgia. METHODS: One Hundred patients recruited from a specialist severe asthma clinic and 1751 people reporting different functional disorder diagnoses recruited via the internet completed the same 60-item questionnaire. Symptom patterns were compared between groups using a new measure, the symptom pattern similarity index where 0 = no relationship, 1 = identical patterns between groups. RESULTS: Severe asthma patients report numerous extra-pulmonary symptoms. The similarity index between the symptom pattern of the asthma patients with other groups was irritable bowel syndrome = 0.54, chronic fatigue syndrome = 0.69, and fibromyalgia = 0.75. The index between fibromyalgia and asthma patients with the most and least frequent extra-pulmonary symptoms was 0.81 and 0.55 respectively. CONCLUSIONS: Patients with severe asthma have numerous extra-pulmonary symptoms similar in type and pattern to the symptoms of fibromyalgia. The similarity of the symptom pattern between asthma and fibromyalgia increases as the number of extra-pulmonary symptoms increases as predicted by network theory and previously shown to be the case with other functional disorders. These findings support the hypothesis that functional disorders and extra-pulmonary asthma symptoms have a common complexity or network aetiology. Evidence based behavioural interventions for fibromyalgia may be helpful for patients with severe asthma reporting extra-pulmonary symptoms.