Usefulness of the Chronic Obstructive Pulmonary Disease Assessment Test to evaluate severity of COPD exacerbations

Predictors of chronic obstructive pulmonary disease exacerbations

PURPOSE OF REVIEW

A frequent-exacerbation phenotype of chronic obstructive pulmonary disease (COPD) exists that is independent of disease severity. Establishment of methods to predict 'frequent exacerbators' is critical. The purpose of this review is to critically assess the recent literature regarding predicting COPD exacerbations, and to provide recommendations for future research.

RECENT FINDINGS

Although there are many studies in which inflammatory biomarkers have been used in an attempt to predict future exacerbations, it is likely that these biomarkers represent a consequence rather than the cause. Genetic predictors are involved in causal pathways. Thus, genetics should be investigated in order to understand the exacerbation mechanism and to develop new therapeutic approaches. Some single nucleotide-type genetic polymorphisms are associated with exacerbations, and the individuals with genotypes protective against infection are less susceptible to exacerbations. In contrast, we reported that loss of Siglec-14, a lectin likely involved in host defense, was associated with a reduced COPD exacerbation risk.

SUMMARY

We should take into consideration that a protein involved in host defense such as Siglec-14, that could also trigger exaggerated response, might also generate unwanted local and systemic inflammation, which could be detrimental to a host and could generate COPD with a frequent-exacerbation phenotype, its progression, and its comorbidities.

Utility of the combination of serum highly-sensitive C-reactive protein level at discharge and a risk index in predicting readmission for acute exacerbation of COPD

OBJECTIVE

Frequent readmissions for acute exacerbations of COPD (AECOPD) are an independent risk factor for increased mortality and use of health-care resources. Disease severity and C-reactive protein (CRP) level are validated predictors of long-term prognosis in such patients. This study investigated the utility of combining serum CRP level with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) exacerbation risk classification for predicting readmission for AECOPD.

METHODS

This was a prospective observational study of consecutive patients hospitalized for AECOPD at Peking University Third Hospital, in Beijing, China. We assessed patient age; gender; smoking status and history (pack-years); lung function; AECOPD frequency during the last year; quality of life; GOLD risk category (A-D; D indicating the greatest risk); and serum level of high-sensitivity CRP at discharge (hsCRP-D).

RESULTS

The final sample comprised 135 patients. Of those, 71 (52.6%) were readmitted at least once during the 12-month follow-up period. The median (interquartile) time to readmission was 78 days (42-178 days). Multivariate analysis revealed that serum hsCRP-D ≥ 3 mg/L and GOLD category D were independent predictors of readmission (hazard ratio = 3.486; 95% CI: 1.968-6.175; p < 0.001 and hazard ratio = 2.201; 95% CI: 1.342-3.610; p = 0.002, respectively). The ordering of the factor combinations by cumulative readmission risk, from highest to lowest, was as follows: hsCRP-D ≥ 3 mg/L and GOLD category D; hsCRP-D ≥ 3 mg/L and GOLD categories A-C; hsCRP-D < 3 mg/L and GOLD category D; hsCRP-D < 3 mg/L and GOLD categories A-C.

CONCLUSIONS

Serum hsCRP-D and GOLD classification are independent predictors of readmission for AECOPD, and their predictive value increases when they are used in combination.

Mini Nutritional Assessment Short-Form predicts exacerbation frequency in patients with chronic obstructive pulmonary disease

BACKGROUND AND OBJECTIVE

Exacerbations of chronic obstructive pulmonary disease (COPD) are a major cause of morbidity, mortality and reduced health status. Thus, to predict and prevent exacerbations is essential for the management of COPD. The aims of this study were to determine whether nutritional status as assessed by the Mini Nutritional Assessment Short-Form (MNA-SF) predicts COPD exacerbation and to compare the ability of the MNA-SF to predict COPD exacerbation with that of the COPD Assessment Test (CAT).

METHODS

Pulmonary function, the modified Medical Research Council (mMRC) scale and body mass index (BMI) were evaluated in 60 stable patients with COPD (mean age, 72 years; mean forced expiratory volume in 1 s (FEV1 ), 51.1% predicted). The MNA-SF and CAT were also completed. Exacerbations were recorded prospectively for 1 year after the initial assessment.

RESULTS

The mean MNA-SF score was 11.4 ± 2.4 (well nourished, 51%; at risk, 37%; and malnourished, 12%). The mean CAT score was 14.4 ± 7.5 (low impact, 37%; medium impact, 38%; high impact, 20%; and very high impact, 5%). The CAT scores were significantly associated with the mMRC scale and %FEV₁, but were not associated with BMI and the MNA-SF score. The exacerbation frequency was associated with the MNA-SF score but not with the CAT score.

CONCLUSIONS

The MNA-SF predicts COPD exacerbation independently of the CAT.

Sputum-to-serum hydrogen sulfide ratio in COPD

OBJECTIVES

Hydrogen sulfide (H₂S) is a gas produced by respiratory cells including smooth muscle cells and may play a role as a cellular gasotransmitter. We evaluated whether H₂S levels in serum or sputum could represent a new biomarker of COPD in a cross-sectional study.

METHODS

H₂S levels in sputum and serum samples were measured using a sulfide-sensitive electrode in 64 patients with stable COPD (S-COPD), 29 COPD subjects during acute exacerbation (AE-COPD), 14 healthy smokers and 21 healthy non-smokers.

RESULTS

Sputum H₂S levels in AE-COPD subjects were higher than those in S-COPD, healthy smoking and non-smoking subjects (p<0.001), but serum H₂S levels in AE-COPD were lower than those in S-COPD (p<0.001). Thus, the sputum-to-serum ratio of H₂S (H₂S ratio) in AE-COPD subjects were higher than those in stable COPD, healthy smoking and non-smoking subjects (p<0.001). In 14 COPD subjects whose H₂S ratios were measured during and after an exacerbation, the mean ratio was increased during exacerbation (p<0.05). H₂S ratio was positively correlated with St. George's Respiratory Questionnaire score, sputum neutrophils and IL-6 and IL-8 levels in sputum and serum (p<0.01) but inversely correlated with sputum macrophages (%), FEV₁%predicted and FEV₁/FVC (p<0.01). The cut-off level of H₂S ratio to indicate an exacerbation was ≥0.44 (sensitivity of 93.1% and specificity of 84.5%).

CONCLUSIONS

The ratio of sputum-to-serum levels of H₂S may provide a useful marker of COPD indicative of obstructive neutrophilic inflammation and of potential ongoing exacerbation.

The COPD assessment test: a systematic review

The COPD assessment test (CAT) is a self-administered questionnaire that measures health-related quality of life. We aimed to systematically evaluate the literature for reliability, validity, responsiveness and minimum clinically important difference (MCID) of the CAT. Multiple databases were searched for studies analysing the psychometric properties of the CAT in adults with chronic obstructive pulmonary disease. Two reviewers independently screened, selected and extracted data, and assessed methodological quality of relevant studies using the COSMIN checklist. From 792 records identified, 36 studies were included. The number of participants ranged from 45 to 6469, mean age from 56 to 73 years, and mean forced expiratory volume in 1 s from 39% to 98% predicted. Internal consistency (reliability) was 0.85-0.98, and test-retest reliability was 0.80-0.96. Convergent and longitudinal validity using Pearson's correlation coefficient were: SGRQ-C 0.69-0.82 and 0.63, CCQ 0.68-0.78 and 0.60, and mMRC 0.29-0.61 and 0.20, respectively. Scores differed with GOLD stages, exacerbation and mMRC grades. Mean scores decreased with pulmonary rehabilitation (2.2-3 units) and increased at exacerbation onset (4.7 units). Only one study with adequate methodology reported an MCID of 2 units and 3.3-3.8 units using the anchor-based approach and distribution-based approach, respectively. Most studies had fair methodological quality. We conclude that the studies support the reliability and validity of the CAT and that the tool is responsive to interventions, although the MCID remains debatable.

Dynamics of inflammation resolution and symptom recovery during AECOPD treatment

The association between increases in both systemic and airway inflammation and acute exacerbation of COPD (AECOPD) has been reported by many studies. However, relatively little is known about the dynamics of inflammation resolution and their correlations with the improvement of clinical indices during treatment. In this study, a total of 93 consecutively hospitalized patients with AECOPD were recruited. Sputum and serum inflammatory markers were measured on the day of admission before treatment (day 0), day 4, 7 and 14 during treatment as well as 8 weeks after discharge. Clinical indices (lung function, dyspnea and COPD assessment test (CAT) scores) were also measured at those time points. By day 4, all airway inflammatory measures rapidly decreased and returned to baseline level. Notably, lung function and dyspnea improved to the baseline level by day 4 as well, consistent with the resolution of respiratory inflammation. However, despite the significant decrease by day 4, systemic inflammation did not reach baseline until day 14, concordant with the decrease in CAT score. In summary, we observed a time lag between the resolution of systemic and airway inflammation, which were correlated with the improvements of different clinical indices.

Evolution of the COPD Assessment Test score during chronic obstructive pulmonary disease exacerbations: determinants and prognostic value

BACKGROUND

An adequate evaluation of exacerbations is a primary objective in managing patients with chronic obstructive pulmonary disease (COPD).

OBJECTIVES

To define the profile of health status recovery during severe exacerbations of COPD using the COPD Assessment Test (CAT) questionnaire and to evaluate its prognostic value.

METHODS

Forty-five patients with previous COPD diagnoses who were hospitalized due to severe exacerbation(s) were included in the study. These patients were treated by their respective physicians following current recommendations; health status was assessed daily using the CAT questionnaire. The CAT score, spirometry and recurrent hospitalizations were recorded one and three months after hospital discharge.

RESULTS

Global initiative for chronic Obstructive Lung Disease (GOLD) stage was an independent determinant for increased CAT score during the first days of exacerbation with respect to postexacerbation values. From hospitalization day 5, the CAT score was similar to that obtained in the stable phase. Body mass index, GOLD stage and education level were related to health status recovery pattern. CAT score increase and the area under the curve of CAT recovery were inversely related to the forced expiratory volume in 1 s achieved three months after discharge (r=-0.606; P<0.001 and r=-0.532; P<0.001, respectively). Patients with recurrent hospitalizations showed higher CAT score increases and slower recovery.

CONCLUSIONS

The CAT detects early health status improvement during severe COPD exacerbations. Its initial worsening and recovery pattern are related to lung function and recurrent hospitalizations.

Derivation of normative data for the COPD assessment test (CAT)

Background

The tradition classification of the severity of COPD, based on spirometry, fails to encompass the heterogeneity of the disease. The COPD assessment test (CAT), a multi-dimensional, patient-filled questionnaire, assesses the overall health status of patients, and is recommended as part of the assessment of individuals with COPD. However, information regarding the range of values for the test in a non-COPD population (normative values) is limited, and consequently, knowledge regarding the optimal cut-off, and the minimum clinically important difference (MCID) for the test remain largely empirical.

Methods

CanCOLD is a population-based multi-center cohort study conducted across Canada, the methodology of which is based on the international BOLD initiative. The study includes subjects with COPD, at-risk individuals who smoke, and healthy control subjects. CAT questionnaires were administered at baseline to all subjects. Among non-COPD subjects, normative values for the CAT questionnaire, and psychometric properties of the test were characterized. Predictors of high CAT scores were identified using multivariable logistic regression.

Results

Of the 525 non-COPD subjects enrolled, 500 were included in the analysis. Mean FEV₁/FVC ratio among the 500 included subjects was 0.77 (SD 0.49); the mean predicted FEV₁ was 99.38% (SD 16.88%). The overall mean CAT score was 6 (SD 5.09); scores were higher among females (6.43, SD 5.59), and subjects over 80 years of age (mean 7.58, SD 6.82). Cronbach alpha for the CAT was 0.79, suggesting a high internal consistency for the test. A score of 16 was the 95th percentile for the population, and 27 subjects (5.4%) were found to have a CAT score > =16. Current smoking (aOR 3.41, 95% CI 1.05, 11.02), subject-reported physician-diagnosed asthma (aOR 7.59, 95% CI 2.71, 21.25) and musculoskeletal disease (aOR 4.09, 95% CI 1.72, 9.71) were found to be significantly associated with a score ≥16.

Conclusions

The characterization of CAT scores in the general population will be useful for norm-based comparisons. Longitudinal follow-up of these subjects will help in the optimization of cut-offs for the test.

Identifying the challenges and facilitators of implementing a COPD care bundle

BACKGROUND

Care bundles have been shown to improve outcomes, reduce hospital readmissions and reduce length of hospital stay; therefore increasing the speed of uptake and delivery of care bundles should be a priority in order to deliver more timely improvements and consistent high-quality care. Previous studies have detailed the difficulties of obtaining full compliance to bundle elements but few have described the underlying reasons for this. In order to improve future implementation this paper investigates the challenges encountered by clinical teams implementing a chronic obstructive pulmonary disease (COPD) care bundle and describes actions taken to overcome these challenges.

METHODS

An initial retrospective documentary analysis of data from seven clinical implementation teams was undertaken to review the challenges faced by the clinical teams. Three focus groups with healthcare professionals and managers explored solutions to these challenges developed during the project.

RESULTS

Documentary analysis identified 28 challenges which directly impacted implementation of the COPD care bundle within five themes; staffing, infrastructure, process, use of improvement methodology and patient and public involvement. Focus groups revealed that the five most significant challenges for all groups were: staff too busy, staff shortages, lack of staff engagement, added workload of the bundle and patient coding issues. The participants shared facilitating factors used to overcome issues including: shifting perceptions to improve engagement, further education sessions to increase staff participation and gaining buy-in from managers through payment frameworks.

CONCLUSIONS

Maximising the impact of a care bundle relies on its successful and timely implementation. Teams implementing the COPD care bundle encountered challenges that were common to all teams and sites. Understanding and learning from the challenges faced by previous endeavours and identifying the facilitators to overcoming these barriers provides an opportunity to mitigate issues that waste time and resources, and ensures that training can be tailored to the anticipated challenges.

COPD assessment tests scores are associated with exacerbated chronic obstructive pulmonary disease in Japanese patients

BACKGROUND

Guidelines recommend chronic obstructive pulmonary disease (COPD) assessment tests (CATs) for evaluation of symptoms and management risks. To investigate whether CAT can predict moderate or severe exacerbations in Japanese COPD patients, a single-blinded prospective study was performed.

METHODS

A 123 Japanese COPD patients were classified into high-CAT (n=64) and low-CAT (n=59) groups. The frequencies and periods of moderate or severe exacerbation and hospitalization were compared between the two groups. Multivariate logistic regression analysis was performed to investigate whether CAT could predict exacerbations. A receiver operating characteristic (ROC) curve analysis was employed to find an appropriate CAT score for exacerbation.

RESULTS

The high-CAT group was significantly older, had a lower body mass index, and had a lower airflow obstruction as compared to the low CAT group. The frequency of moderate or severe exacerbation (1.3±1.3 events per patient per year, p<0.0001) and hospitalizations (0.2±0.4, p=0.0202) in the high-CAT group was significantly higher than in the low-CAT group (0.4±0.7 and 0.0±0.1, respectively). Multivariate logistic regression analysis showed that both high CAT score and low airflow obstruction were independently predictive of frequent moderate or severe COPD exacerbation. ROC analysis showed that the best cut-off CAT score for moderate or severe COPD exacerbation was 8 points.

CONCLUSION

Our present results indicate that COPD Japanese patients showing high CAT scores have a poor prognosis, and that the CAT score is able to predict exacerbation in Japanese COPD.

Portuguese-language version of the COPD Assessment Test: validation for use in Brazil

OBJECTIVE

To validate a Portuguese-language version of the COPD assessment test (CAT) for use in Brazil and to assess the reproducibility of this version.

METHODS

This was multicenter study involving patients with stable COPD at two teaching hospitals in the city of Fortaleza, Brazil. Two independent observers (twice in one day) administered the Portuguese-language version of the CAT to 50 patients with COPD. One of those observers again administered the scale to the same patients one week later. At baseline, the patients were submitted to pulmonary function testing and the six-minute walk test (6MWT), as well as completing the previously validated Portuguese-language versions of the Saint George's Respiratory Questionnaire (SGRQ), modified Medical Research Council (MMRC) dyspnea scale, and hospital anxiety and depression scale (HADS).

RESULTS

Inter-rater and intra-rater reliability was excellent (intraclass correlation coefficient [ICC] = 0.96; 95% CI: 0.93-0.97; p < 0.001; and ICC = 0.98; 95% CI: 0.96-0.98; p < 0.001, respectively). Bland Altman plots showed good test-retest reliability. The CAT total score correlated significantly with spirometry results, 6MWT distance, SGRQ scores, MMRC dyspnea scale scores, and HADS-depression scores.

CONCLUSIONS

The Portuguese-language version of the CAT is a valid, reproducible, and reliable instrument for evaluating patients with COPD in Brazil.

Bacterial infection, airway and systemic inflammation and clinical outcomes before and after treatment of AECOPD, a longitudinal and cross-sectional study

Abstract Bacterial infection is a major cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD), which are associated with significantly increased airway and systemic inflammation. However, the relationship among bacteriology, the resolution of inflammation and clinical outcomes is largely unknown. In this study, we recruited consecutive patients hospitalized for AECOPD with purulent sputum. We measured the airway and systemic inflammation levels, the COPD assessment test (CAT) score and adverse outcomes between patients with and without potentially pathogenic microorganisms (PPM). Among sputum samples collected from the 135 episodes of AECOPD, 42 (31.1%) were PPM-positive at admission. Compared with those in the PPM-negative group, more patients in the PPM-positive group had ≥2 exacerbations in previous year and Anthonisen type I at admission and higher drop in sputum neutrophil, serum hs-CRP and CAT value from exacerbation to the subsequent baseline. No significant differences in the adverse outcomes between the two groups were observed. Among the 38 PPM-positive patients who survived and were discharged from hospital, 19 remained PPM-positive (bacterial persistence group) and 19 PPM-negative (bacterial clearance group). Both inflammation indices and CAT score decreased compared to admission in the two groups, regardless of the bacteriology at discharge. Our data suggest uncultivated bacteria and/or virus might also play important roles in causing inflammation and AECOPD.

COPD assessment test: a simple tool to evaluate disease severity and response to treatment

The COPD assessment test (CAT) is a short questionnaire designed to assess the impairment in health status of COPD patients. We aimed to determine the change of the CAT in COPD patients after 1 year of treatment and test the association between the score and clinical and lung function variables. Methods A cohort of 111 newly diagnosed COPD patients in primary care was evaluated at baseline and one year after the implementation of the recommended treatment according to the Global Initiative for the management of COPD (GOLD). Results Most of the patients (82%) were diagnosed with mild to moderate airflow limitation (mean FEV1 72 ± 21.5% predicted) and the CAT score increased in proportion with the GOLD stage of severity. The CAT significantly correlated with the number of exacerbations, visits to general practitioners and days of hospitalization both at the beginning and at 1 year follow-up. A strong negative correlation between the CAT score and FEV1 predicted was also observed. The CAT was responsive to the application of treatment with a significant improvement in the mean score (95% confidence interval) following 12 months of treatment by -2.4 (-2.9, -1.9) despite the small decline in lung function indices. The number of exacerbations in the preceding year and FEV1 were independent predictors of the CAT score in the general linear model. Conclusion The CAT questionnaire may serve as a simple, measurable tool complementary to spirometry in the assessment of severity and of response to treatment in unselected COPD patients in primary care.

Utility of the CAT in the therapy assessment of COPD exacerbations in China

BACKGROUND

Chronic obstructive pulmonary disease (COPD) exacerbations are accompanied with increased systemic inflammation, which accelerate the pulmonary function injury and impair the quality of life. Prompt and effective treatments for COPD exacerbations slow down the disease progression, but an objective instrument to assess the efficacy of the treatments following COPD exacerbations is lacking nowadays. The COPD Assessment Test (CAT) is an 8-item questionnaire designed to assess and quantify health status and symptom burden in COPD patients. We hypothesize that the change in CAT score is related to the treatment response following COPD exacerbations.

METHODS

78 inpatients with clinician-diagnosed acute exacerbation of COPD (AECOPD) completed the CAT, St George's Respiratory Questionnaire (SGRQ) and modified Medical Research Council (mMRC) Dyspnea Scale both at exacerbation and the 7th day of therapy, and a subgroup of 39 patients performed the pulmonary function test. Concentrations of serum C-reactive protein (CRP) and plasma fibrinogen were assayed at the same time. Correlations between the CAT and other measurements were examined.

RESULTS

After 7 days' therapy, the CAT and SGRQ scores, mMRC grades, as well as the concentrations of CRP and fibrinogen all decreased significantly (P < 0.001). Meanwhile, the FEV1% predicted had a significant improvement (P < 0.001). The CAT scores were significantly correlated with concurrent concentrations of CRP and fibrinogen, SGRQ scores, FEV1% predicted and mMRC grades (P < 0.05). The change in CAT score was positively correlated with the change of CRP (r = 0.286, P < 0.05), SGRQ score (r = 0.725, P < 0.001) and mMRC grades (r = 0.593, P < 0.001), but not with fibrinogen (r = 0.137, P > 0.05) or FEV1% predicted (r = -0.101, P > 0.05). No relationship was found between the changes of SGRQ score and CRP and fibrinogen (P>0.05).

CONCLUSIONS

The CAT is associate with the changes of systemic inflammation following COPD exacerbations. Moreover, the CAT is responsive to the treatments, similar to other measures such as SGRQ, mMRC dyspnea scale and pulmonary function. Therefore, the CAT is a potentially useful instrument to assess the efficacy of treatments following COPD exacerbations.

Minimum clinically important difference for the COPD Assessment Test: a prospective analysis

BACKGROUND

The COPD Assessment Test (CAT) is responsive to change in patients with chronic obstructive pulmonary disease (COPD). However, the minimum clinically important difference (MCID) has not been established. We aimed to identify the MCID for the CAT using anchor-based and distribution-based methods.

METHODS

We did three studies at two centres in London (UK) between April 1, 2010, and Dec 31, 2012. Study 1 assessed CAT score before and after 8 weeks of outpatient pulmonary rehabilitation in patients with COPD who were able to walk 5 m, and had no contraindication to exercise. Study 2 assessed change in CAT score at discharge and after 3 months in patients admitted to hospital for more than 24 h for acute exacerbation of COPD. Study 3 assessed change in CAT score at baseline and at 12 months in stable outpatients with COPD. We focused on identifying the minimum clinically important improvement in CAT score. The St George's Respiratory Questionnaire (SGRQ) and Chronic Respiratory Questionnaire (CRQ) were measured concurrently as anchors. We used receiver operating characteristic curves, linear regression, and distribution-based methods (half SD, SE of measurement) to estimate the MCID for the CAT; we included only patients with paired CAT scores in the analysis.

FINDINGS

In Study 1, 565 of 675 (84%) patients had paired CAT scores. The mean change in CAT score with pulmonary rehabilitation was -2·5 (95% CI -3·0 to -1·9), which correlated significantly with change in SGRQ score (r=0·32; p<0·0001) and CRQ score (r=-0·46; p<0·0001). In Study 2, of 200 patients recruited, 147 (74%) had paired CAT scores. Mean change in CAT score from hospital discharge to 3 months after discharge was -3·0 (95% CI -4·4 to -1·6), which correlated with change in SGRQ score (r=0·47; p<0·0001). In Study 3, of 200 patients recruited, 164 (82%) had paired CAT scores. Although no significant change in CAT score was identified after 12 months (mean 0·6, 95% CI -0·4 to 1·5), change in CAT score correlated significantly with change in SGRQ score (r=0·36; p<0·0001). Linear regression estimated the minimum clinically important improvement for the CAT to range between -1·2 and -2·8 with receiver operating characteristic curves consistently identifying -2 as the MCID. Distribution-based estimates for the MCID ranged from -3·3 to -3·8.

INTERPRETATION

The most reliable estimate of the minimum important difference of the CAT is 2 points. This estimate could be useful in the clinical interpretation of CAT data, particularly in response to intervention studies.

FUNDING

Medical Research Council and UK National Institute of Health Research.

Time course of inflammation resolution in patients with frequent exacerbations of chronic obstructive pulmonary disease

BACKGROUND

When exacerbation of chronic obstructive pulmonary disease (AECOPD) occurs frequently, patients have high levels of airway and systemic inflammation and a poor quality of life. This study compared the nature and course of systemic and airway inflammation during AECOPD between patients who experienced frequent exacerbations and those with non-frequent exacerbations.

MATERIAL AND METHODS

Consecutive hospitalized patients with AECOPD were recruited and divided into 2 groups according to the frequency of AECOPD they had experienced in the previous year. Frequent exacerbators (defined as 2 or more AECOPD in the previous year) and non-frequent exacerbators (defined as zero or 1 AECOPD in the previous year). Inflammatory (interleukin 6, interleukin 8, myeloperoxidase, and C-reactive protein) and clinical (dyspnea, COPD assessment test (CAT), and peak expiratory flow) indices were assessed on the day of admission before starting therapy, day 7 of treatment, the day of planned discharge (day 10-14), and 8 weeks after discharge.

RESULTS

We analyzed data from 135 patients; 78 (57.8%) were non-frequent exacerbators and 57 (42.2%) were frequent exacerbators. In both groups, the inflammatory and clinical indices at day 7, the day of planned discharge (day 10-14), and 8 weeks were significantly improved compared to those at admission. Frequent exacerbators had a smaller reduction in their inflammatory indices and CAT scores between exacerbation onset and all the other time points compared with infrequent exacerbators.

CONCLUSIONS

Frequent exacerbators have a reduced response to treatment of AECOPD in terms of inflammatory indices and quality of life.

Health status during hospitalisations for chronic obstructive pulmonary disease exacerbations: the validity of the Clinical COPD Questionnaire

Hospitalisations for chronic obstructive pulmonary disease (COPD) exacerbations are characterised by a significant worsening of the respiratory symptoms which can impair the health status (HS). However little is known on the HS behaviour during such events. Prospective study evaluating the validity of the Clinical COPD Questionnaire (CCQ) as a HS measure in hospitalisations for COPD exacerbations. The CCQ total score (CCQ-T) correlated with EQ-VAS (-0.51, p < 0.0001), was able to discriminate between longer and shorter duration hospitalisation (CCQ-T 3.83 vs 3.03, respectively p = 0.001), had a Cronbach-α of 0.86, and improved significantly over the hospitalisation period (CCQ-T on day 7 of hospitalisation 2.55 vs 3.77 at baseline, p < 0.0001). CCQ is an excellent tool for the assessment of the HS dynamics in hospitalisations for COPD exacerbations.

Analysis of comorbid factors that increase the COPD assessment test scores

BACKGROUND

The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) is a concise health status measure for COPD. COPD patients have a variety of comorbidities, but little is known about their impact on quality of life. This study was designed to investigate comorbid factors that may contribute to high CAT scores.

METHODS

An observational study at Keio University and affiliated hospitals enrolled 336 COPD patients and 67 non-COPD subjects. Health status was assessed by the CAT, the St. Georges Respiratory Questionnaire (SGRQ), and all components of the Medical Outcomes Study Short-Form 36-Item (SF-36) version 2, which is a generic measure of health. Comorbidities were identified based on patients' reports, physicians' records, and questionnaires, including the Frequency Scale for the Symptoms of Gastro-esophageal reflux disease (GERD) and the Hospital Anxiety and Depression Scale. Dual X-ray absorptiometry measurements of bone mineral density were performed.

RESULTS

The CAT showed moderate-good correlations with the SGRQ and all components of the SF-36. The presence of GERD, depression, arrhythmia, and anxiety was significantly associated with a high CAT score in the COPD patients.

CONCLUSIONS

Symptomatic COPD patients have a high prevalence of comorbidities. A high CAT score should alert the clinician to a higher likelihood of certain comorbidities such as GERD and depression, because these diseases may co-exist unrecognized.

TRIAL REGISTRATION

Clinical trial registered with UMIN (UMIN000003470).

The COPD assessment test (CAT) assists prediction of COPD exacerbations in high-risk patients

We evaluated the predictive value of the COPD assessment test (CAT™) for exacerbation in the following six months or time to first exacerbation among COPD patients with previous exacerbations. COPD outpatients with a history of exacerbation from 19 hospitals completed the CAT questionnaire and spirometry over six months. Exacerbation events were prospectively collected using a structured questionnaire. The baseline CAT score categorised into four groups (0-9, 10-19, 20-29, and 30-40) showed strong prediction for time to first exacerbation and modest prediction for any exacerbation or moderate-severe exacerbation (AUC 0.83, 0.64, and 0.63 respectively). In multivariate analyses, the categorised CAT score independently predicted all three outcomes (p = 0.001 or p < 0.001). Compared with the lowest CAT score category, the higher categories were associated with significantly shorter time to first exacerbation and higher exacerbation risks. The corresponding adjusted median time was >24, 14, 9, and 5 weeks and the adjusted RR was 1.00, 1.30, 1.37, and 1.50 in the category of 0-9, 10-19, 20-29, and 30-40 respectively. Exacerbation history (≥2 vs. 1 event in the past year) was related to time to first exacerbation (adjusted HR 1.35; p = 0.023) and any exacerbation during the study period (adjusted RR 1.15; p = 0.016). The results of this study support the use of the CAT as a simple tool to assist in the identification of patients at increased risk of exacerbations. This could facilitate timely and cost-effective implementation of preventive interventions, and improve health resource allocation.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT01254032.

Antibiotics for acute and chronic respiratory infection in patients with chronic obstructive pulmonary disease

Prevention and effective treatment of exacerbations are major objectives in the management of patients with chronic obstructive pulmonary disease (COPD). Antibiotics are mainstay treatment for patients with severe COPD with an acute exacerbation that includes increased sputum purulence and worsening shortness of breath. Although such treatment is associated with clinical benefit, treatment failure and relapse rates may be high, particularly in cases of inadequate antibiotic therapy through incomplete resolution of the initial exacerbation and persistent bacterial infection. These aspects have led to recommendations for a stratified approach to antibiotic therapy based on patient characteristics associated with increased risk factors for failure. Patients at greatest risk for poor outcome (i.e., those with severe COPD) are likely to derive greatest benefit from early treatment with antibiotics. Long-term or intermittent antibiotic treatment has been shown to prevent COPD exacerbations and hospitalizations. These effects may be achieved by reducing bacterial load in the airways in stable state and/or bronchial inflammation. Although systemic antibiotics are likely to remain the core treatment for patients with moderate to severe exacerbated COPD, inhaled antibiotics may represent a more optimal approach for the treatment and prevention of COPD exacerbations in the future. Regardless of the route of administration, further studies are required to evaluate the potential long-term adverse events of antibiotics and the development of bacterial resistance.

Assessment of health status in patients with newly diagnosed chronic obstructive pulmonary disease

Subject

Chronic obstructive pulmonary disease (COPD) is a common disease worldwide. This study aimed to investigate the health status of patients with newly diagnosed COPD.

Methods

A total of 45 healthy controls and 218 patients with newly diagnosed COPD were recruited. Pulmonary function test (PFT) values, COPD assessment test (CAT) scores, exacerbation history, and demographics were recorded.

Results

Forced expiratory volume in 1 s percent (FEV1%) predicted was significantly decreased and the CAT score was significantly increased in patients with COPD compared with healthy controls (P <0.001). Among the COPD patients, the most commonly reported respiratory symptoms were cough (86.7%), sputum (80.3%), and dyspnea (45%). A total of 86.2% patients were in the moderate or severe stage (spirometric classification) of COPD, and 71.5% were in Group C or Group D (combined assessment). A total of 33.9% of the patients had 2 or more exacerbations in the previous year. Nearly half of the patients (45.4%) had a high CAT score of ≥10. Patients with a history of more exacerbations had a higher CAT score.

Conclusions

Most COPD patients were symptomatic and appeared to have moderate to severe airflow limitation or a high risk of exacerbation before definitely being diagnosed with COPD using the PFT.

Hydrogen peroxide content and pH of expired breath condensate from patients with asthma and COPD

BACKGROUND

Oxidative stress is implicated in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). Analysis of the expired breath condensate (EBC) has been suggested to provide non-invasive inflammatory markers that reflect oxidative stress in the airways.

OBJECTIVE

The present study attempts to elucidate whether the hydrogen peroxide (H2O2) levels and pH values in EBC may be useful as biomarkers of the activity or severity of asthma and COPD.

METHODS

We measured the H2O2 levels and pH values using a derivatives of reactive oxygen metabolites exhalation test kit (Diacron) and a pH analyser, respectively, in EBC obtained using an EcoScreen from 29 patients with asthma, 33 with COPD, and 33 healthy individuals (all non-smokers). We then examined the relationships among oxidative stress and the asthma control test (ACT) or COPD assessment test (CAT) scores, pulmonary function, fractional exhaled nitric oxide (FeNO), and the extent of low attenuation areas on HRCT.

RESULTS

The H2O2 levels were elevated and pH was lower in both asthma (H2O2; 8.75 ± 0.88 μM, p < 0.01, pH; 7.14 ± 0.07, p < 0.05) and COPD (H2O2; 7.44 ± 0.89 μM, p < 0.01, pH; 6.87 ± 0.10, p < 0.01) compared with control subjects (H2O2; 3.42 ± 0.66 μM, pH; 7.35 ± 0.04). Neither the H2O2 levels nor pH correlated with the ACT scores and FeNO in asthma patients. Neither the H2O2 levels nor pH significantly correlated with the pulmonary function in asthma and COPD. However, the CAT scores significantly correlated with the H2O2 levels in patients with COPD (r = 0.52, p < 0.01).

CONCLUSIONS

These findings suggest that oxidative stress is involved in the pathogenesis of asthma and COPD and that the H2O2 levels in EBC might reflect the health status in COPD.

Course of COPD assessment test (CAT) and clinical COPD questionnaire (CCQ) scores during recovery from exacerbations of chronic obstructive pulmonary disease

Introduction

COPD exacerbations have a negative impact on lung function, decrease quality of life (QoL) and increase the risk of death. The objective of this study was to assess the course of health status after an outpatient or inpatient exacerbation in patients with COPD.

Methods

This is an epidemiological, prospective, multicentre study that was conducted in 79 hospitals and primary care centres in Spain. Four hundred seventy-six COPD patients completed COPD assessment test (CAT) and Clinical COPD Questionnaire (CCQ) questionnaires during the 24 hours after presenting at hospital or primary care centres with symptoms of an exacerbation, and also at weeks 4–6. The scores from the CAT and CCQ were evaluated and compared at baseline and after recovery from the exacerbation.

Results

A total of 164 outpatients (33.7%) and 322 inpatients (66.3%) were included in the study. The majority were men (88.2%), the mean age was 69.4 years (SD = 9.5) and the mean FEV1 (%) was 47.7% (17.4%). During the exacerbation, patients presented high scores in the CAT: [mean: 22.0 (SD = 7.0)] and the CCQ: [mean: 4.4 (SD = 1.2)]. After recovery there was a significant reduction in the scores of both questionnaires [CAT: mean: -9.9 (SD = 5.1) and CCQ: mean: -3.1 (SD = 1.1)]. Both questionnaires showed a strong correlation during and after the exacerbation and the best predictor of the magnitude of improvement in the scores was the severity of each score at onset.

Conclusions

Due to their good correlation, CAT and CCQ can be useful tools to measure health status during an exacerbation and to evaluate recovery. However, new studies are necessary in order to identify which factors are influencing the course of the recovery of health status after a COPD exacerbation.

Mechanisms and impact of the frequent exacerbator phenotype in chronic obstructive pulmonary disease

Exacerbations of chronic obstructive pulmonary disease (COPD) are important events that carry significant consequences for patients. Some patients experience frequent exacerbations, and are now recognized as a distinct clinical subgroup, the 'frequent exacerbator' phenotype. This is relatively stable over time, occurs across disease severity, and is associated with poorer health outcomes. These patients are therefore a priority for research and treatment. The pathophysiology underlying the frequent exacerbator phenotype is complex, with increased airway and systemic inflammation, dynamic lung hyperinflation, changes in lower airway bacterial colonization and a possible increased susceptibility to viral infection. Frequent exacerbators are also at increased risk from comorbid extrapulmonary diseases including cardiovascular disease, gastroesophageal reflux, depression, osteoporosis and cognitive impairment. Overall these patients have poorer health status, accelerated forced expiratory volume over 1 s (FEV1) decline, worsened quality of life, and increased hospital admissions and mortality, contributing to increased exacerbation susceptibility and perpetuation of the frequent exacerbator phenotype. This review article sets out the definition and importance of the frequent exacerbator phenotype, with a detailed examination of its pathophysiology, impact and interaction with other comorbidities.

Day-to-day measurement of patient-reported outcomes in exacerbations of chronic obstructive pulmonary disease

Background

Exacerbations of chronic obstructive pulmonary disease (COPD) are a major burden to patients and to society. Little is known about the possible role of day-to-day patient-reported outcomes during an exacerbation. This study aims to describe the day-to-day course of patient-reported health status during exacerbations of COPD and to assess its value in predicting clinical outcomes.

Methods

Data from two randomized controlled COPD exacerbation trials (n = 210 and n = 45 patients) were used to describe both the feasibility of daily collection of and the day-to-day course of patient-reported outcomes during outpatient treatment or admission to hospital. In addition to clinical parameters, the BORG dyspnea score, the Clinical COPD Questionnaire (CCQ), and the St George’s Respiratory Questionnaire were used in Cox regression models to predict treatment failure, time to next exacerbation, and mortality in the hospital study.

Results

All patient-reported outcomes showed a distinct pattern of improvement. In the multivariate models, absence of improvement in CCQ symptom score and impaired lung function were independent predictors of treatment failure. Health status and gender predicted time to next exacerbation. Five-year mortality was predicted by age, forced expiratory flow in one second % predicted, smoking status, and CCQ score. In outpatient management of exacerbations, health status was found to be less impaired than in hospitalized patients, while the rate and pattern of recovery was remarkably similar.

Conclusion

Daily health status measurements were found to predict treatment failure, which could help decision-making for patients hospitalized due to an exacerbation of COPD.

Differences in classification of COPD group using COPD assessment test (CAT) or modified Medical Research Council (mMRC) dyspnea scores: a cross-sectional analyses

BACKGROUND

The GOLD 2011 document proposed a new classification system for COPD combining symptom assessment by COPD assessment test (CAT) or modified Medical Research Council (mMRC) dyspnea scores, and exacerbation risk. We postulated that classification of COPD would be different by the symptom scale; CAT vs mMRC.

METHODS

Outpatients with COPD were enrolled from January to June in 2012. The patients were categorized into A, B, C, and D according to the GOLD 2011; patients were categorized twice with mMRC and CAT score for symptom assessment, respectively. Additionally, correlations between mMRC scores and each item of CAT scores were analyzed.

RESULTS

Classification of 257 patients using the CAT score vs mMRC scale was as follows. By using CAT score, 60 (23.3%) patients were assigned to group A, 55 (21.4%) to group B, 21 (8.2%) to group C, and 121 (47.1%) to group D. On the basis of the mMRC scale, 97 (37.7%) patients were assigned to group A, 18 (7.0%) to group B, 62 (24.1%) to group C, and 80 (31.1%) to group D. The kappa of agreement for the GOLD groups classified by CAT and mMRC was 0.510. The mMRC score displayed a wide range of correlation with each CAT item (r = 0.290 for sputum item to r = 0.731 for dyspnea item, p < 0.001).

CONCLUSIONS

The classification of COPD produced by the mMRC or CAT score was not identical. Care should be taken when stratifying COPD patients with one symptom scale versus another according to the GOLD 2011 document.

GOLD 2011 disease severity classification in COPDGene: a prospective cohort study

BACKGROUND

The 2011 GOLD (Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease [COPD]) consensus report uses symptoms, exacerbation history, and forced expiratory volume (FEV1)% to categorise patients according to disease severity and guide treatment. We aimed to assess both the influence of symptom instrument choice on patient category assignment and prospective exacerbation risk by category.

METHODS

Patients were recruited from 21 centres in the USA, as part of the COPDGene study. Eligible patients were aged 45-80 years, had smoked for 10 pack-years or more, and had an FEV1/forced vital capacity (FVC) <0·7. Categories were defined with the modified Medical Research Council (mMRC) dyspnoea scale (score 0-1 vs ≥2) and the St George's Respiratory Questionnaire (SGRQ; ≥25 vs <25 as a surrogate for the COPD Assessment Test [CAT] ≥10 vs <10) in addition to COPD exacerbations in the previous year (<2 vs ≥ 2), and lung function (FEV1% predicted ≥50 vs <50). Statistical comparisons were done with k-sample permutation tests. This study cohort is registered with ClinicalTrials.gov, number NCT00608764.

FINDINGS

4484 patients with COPD were included in this analysis. Category assignment using the mMRC scale versus SGRQ were similar but not identical. On the basis of the mMRC scale, 1507 (33·6%) patients were assigned to category A, 919 (20·5%) to category B, 355 (7·9%) to category C, and 1703 (38·0%) to category D; on the basis of the SGRQ, 1317 (29·4%) patients were assigned to category A, 1109 (24·7%) to category B, 221 (4·9%) to category C, and 1837 (41·0%) to category D (κ coefficient for agreement, 0·77). Significant heterogeneity in prospective exacerbation rates (exacerbations/person-years) were seen, especially in the D subcategories, depending on the risk factor that determined category assignment (lung function only [0·89, 95% CI 0·78-1·00]), previous exacerbation history only [1·34, 1·0-1·6], or both [1·86, 1·6-2·1; p<0·0001]).

INTERPRETATION

The GOLD classification emphasises the importance of symptoms and exacerbation risk when assessing COPD severity. The choice of symptom measure influences category assignment. The relative number of patients with low symptoms and high risk for exacerbations (category C) is low. Differences in exacerbation rates for patients in the highest risk category D were seen depending on whether risk was based on lung function, exacerbation history, or both.

FUNDING

National Heart, Lung, and Blood Institute, and the COPD Foundation through contributions from AstraZeneca, Boehringer Ingelheim, Novartis, and Sepracor.

Indacaterol improves daily physical activity in patients with chronic obstructive pulmonary disease

Background

The current mainstay of therapy for chronic obstructive pulmonary disease (COPD) is long-acting bronchodilators. To date, the effect of indacaterol, a β2-agonist, on activities of daily living in COPD patients is not well understood. The aim of this study was to evaluate the efficacy of indacaterol with regard to activities of daily living in patients with COPD.

Methods

In this nonrandomized open-label study, 23 patients with COPD were instructed to carry an accelerometer for 4 weeks without indacaterol therapy and then for another period of 4 weeks while receiving indacaterol therapy.

Results

The number of steps, duration of moderate or greater physical activity, and energy expenditure were significantly increased after treatment with indacaterol compared with baseline data in all patients with COPD; the metabolic equivalent of task was also significantly enhanced after treatment with indacaterol.

Conclusion

This study provides early evidence that indacaterol improves daily physical activity in patients with COPD.

An integrated approach to the medical treatment of chronic obstructive pulmonary disease

COPD is a treatable condition for which careful and objective evaluation of patients’ lung function, symptoms, exercise capacity, and exacerbation history on an ongoing basis is essential so that treatments may be individualized as much as possible. Although the comparative effectiveness of drug classes has not yet been tested completely in COPD, virtually all inhaled COPD therapies improve lung function, quality of life, and reduce COPD exacerbations, which fulfills the major goals of care. Pulmonary rehabilitation is safe, effective, and a crucial component of COPD therapy. Newer therapies have been developed with the specific purpose of reducing COPD exacerbations and should be prescribed to individuals who have evidence of recurrent exacerbations despite maximal inhaled maintenance medications.

Blood fibrinogen as a biomarker of chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a multicomponent condition that is characterised by airflow obstruction that is not fully reversible and is a major global cause of morbidity and mortality. The most widely used marker of disease severity and progression is FEV₁. However, FEV₁ correlates poorly with both symptoms and other measures of disease progression and thus there is an urgent need for other biological markers to better characterise individuals with COPD. Fibrinogen is an acute phase plasma protein that has emerged as a promising biomarker in COPD. Here we review the current clinical evidence linking fibrinogen with COPD and its associated co-morbidities and discuss its potential utility as a biomarker.

Methods

Searches for appropriate studies were undertaken on PubMed using search terms fibrinogen, COPD, emphysema, chronic bronchitis, FEV₁, cardiovascular disease, exacerbation and mortality.

Results

There is strong evidence of an association between fibrinogen and the presence of COPD, the presence and frequency of exacerbations and with mortality. Fibrinogen is associated with disease severity but does not predict lung function decline, a measure used as a surrogate for disease activity. The role of fibrinogen in identifying inflammatory co morbidities, particularly cardiovascular disease, remains unclear. Fibrinogen is reduced by p38 mitogen-activated protein kinase inhibitors in individuals with stable disease and by oral corticosteroids during exacerbations.

Conclusions

Fibrinogen is likely to be a useful biomarker to stratify individuals with COPD into those with a high or low risk of future exacerbations and may identify those with a higher risk of mortality.