Different Pattern of Chronic Obstructive Pulmonary Disease Assessment Test Score between Chronic Bronchitis and Non-chronic Bronchitis Patients

Characteristics and phenotypes of a COPD cohort from referral hospital clinics in Uganda

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a heterogeneous condition with varied clinical and pathophysiological characteristics. Although there is increasing evidence that COPD in low-income and middle-income countries may have different clinical characteristics from that in high-income countries, little is known about COPD phenotypes in these settings. We describe the clinical characteristics and risk factor profile of a COPD population in Uganda.

METHODS

We cross sectionally analysed the baseline clinical characteristics of 323 patients with COPD aged 30 years and above who were attending 2 national referral outpatient facilities in Kampala, Uganda between July 2019 and March 2021. Logistic regression was used to determine factors associated with spirometric disease severity.

RESULTS

The median age was 62 years; 51.1% females; 93.5% scored COPD Assessment Test >10; 63.8% modified medical research council (mMRC) >2; 71.8% had wheezing; 16.7% HIV positive; 20.4% had a history of pulmonary tuberculosis (TB); 50% with blood eosinophilic count >3%, 51.7% had 3 or more exacerbations in the past year. Greater severity by Global initiative for Chronic Obstructive Lung Disease (GOLD) stage was inversely related to age (aOR=0.95, 95% CI 0.92 to 0.97), and obesity compared with underweight (aOR=0.25, 95% CI 0.07 to 0.82). Regarding clinical factors, more severe airflow obstruction was associated with SPO2 <93% (aOR=3.79, 95% CI 2.05 to 7.00), mMRC ≥2 (aOR=2.21, 95% CI 1.08 to 4.53), and a history of severe exacerbations (aOR=2.64, 95% CI 1.32 to 5.26).

CONCLUSION

Patients with COPD in this population had specific characteristics and risk factor profiles including HIV and TB meriting tailored preventative approaches. Further studies are needed to better understand the pathophysiological mechanisms at play and the therapeutic implications of these findings.

Clinical Characteristics of COPD Patients According to COPD Assessment Test (CAT) Score Level: Cross-Sectional Study

PURPOSE

The chronic obstructive pulmonary disease (COPD) assessment test (CAT) is widely used to assess the impact of COPD symptoms on health status. Whilst the CAT consists of eight different items, details on the distribution of each item are limited. This study aimed to investigate the distribution and clinical implication of each CAT item, stratified by CAT severity group, in stable COPD patients.

PATIENTS AND METHODS

This was a cross-sectional study at a single referral hospital in South Korea. Spirometry confirmed COPD patients with CAT measured at the first clinical visit were retrospectively identified. Patients were categorized into three groups: low (0 ≤ CAT < 10), medium (10 ≤ CAT < 20), and high (20 ≤ CAT ≤ 40) impact group. For the purpose of this analysis, the first four items (cough, sputum, chest tightness, and dyspnea) and the remaining four items (activities, confidence, sleep and energy) were also grouped as "pulmonary" and "extra-pulmonary", respectively.

RESULTS

A total of 815 patients were included, and mean (SD) forced expiratory volume in 1 s (FEV1) was 62.8 (17.4) % pred. Among them, 300 patients (36.8%) were in the high impact group and had a greater exacerbation history and lower lung function. The proportion of "extra-pulmonary" items score was greater in patients with higher total CAT scores, with the activity and confidence items showing higher scores.

CONCLUSION

In our study, in addition to dyspnea, activity limitation is a particular problem in individual patients with higher CAT total scores, for which physicians need to pay more attention. Our study suggests that whilst CAT total score captures the overall impact of COPD, each item of the CAT contains potentially useful information in understanding the patient's symptom burden.

Chronic Cough and Phlegm in Subjects Undergoing Comprehensive Health Examination in Japan - Survey of Chronic Obstructive Pulmonary Disease Patients Epidemiology in Japan (SCOPE-J)

Purpose

The purpose of this study was to estimate the prevalence of subjects with chronic cough and phlegm and describe their characteristics including the presence or absence of airflow limitation among the general population in Japan.

Subjects and Methods

This was an observational cross-sectional survey targeting multiple regions of Japan. Subjects aged 40 years or above who were undergoing comprehensive health examination were recruited. The existence of chronic cough and phlegm, airflow limitation, and treatment for respiratory diseases were examined. Chronic cough and phlegm were defined as having both symptoms for at least 3 months of the year and for at least 2 consecutive years, or as receiving any treatment for chronic bronchitis at the time of recruitment. Airflow limitation was defined as forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) less than 0.7.

Results

In a total of 22,293 subjects, 380 subjects (1.7%) had chronic cough and phlegm. Among these 380 subjects, 21.8% received treatment for a respiratory disease, and 11.6% had airflow limitation. Compared to subjects without both chronic cough and phlegm but with airflow limitation, subjects with chronic cough and phlegm without airflow limitation were younger, more likely to be current smokers (39.6%), and had higher total scores on a chronic obstructive pulmonary disease (COPD) assessment test (CAT). Scores of CAT questions 1-4 (cough, phlegm, chest tightness, breathlessness, respectively) were higher in subjects with chronic cough and phlegm regardless of airflow limitation.

Conclusion

This study demonstrated that subjects identified to have chronic cough and phlegm in comprehensive health examination settings were symptomatic, while most of them did not receive any treatment for respiratory diseases and did not have airflow limitation. Screening subjects for chronic cough and phlegm in a comprehensive health examination followed by a detailed examination of screened subjects could be an effective approach for better management of chronic cough and phlegm. Smoking cessation should be included in the management, in consideration that around 40% of subjects with chronic cough and phlegm were current smokers.

Mixed Phenotype of Emphysema and Airway Wall Thickening Is Associated with Frequent Exacerbation in Chronic Obstructive Pulmonary Disease Patients

Objective

The presence of both emphysema and airway wall thickening determined via volumetric computed tomography (CT) is defined as mixed phenotype. The long-term clinical course of this phenotype has not been studied in depth. This study compared the mixed phenotype to other phenotypes of chronic obstructive pulmonary disease (COPD) patients.

Methods

COPD patients enrolled in the Korean Obstructive Lung Disease (KOLD) study from June 2005 to October 2015 were evaluated. The emphysema index and the percentage of bronchial mean wall area were calculated from volumetric CT scans. Patients with COPD were classified into four phenotypes using two cutoffs: emphysema index of 15% and median value of mean wall area (MWA%).

Results

Of 435 patients with COPD, 99 (22.8%) were defined as CT-normal type, 119 (27.4%) as emphysema-dominant type, 113 (26.0%) as airway-dominant type, and 104 (23.9%) as mixed type. The mixed phenotype showed the highest baseline total COPD Assessment Test (CAT) and St. George’s Respiratory Questionnaire (SGRQ) scores. Moreover, it had the highest proportion of patients experiencing exacerbation of COPD (50.0%), and had the lowest baseline FEV1. Lower BMI, GOLD stages III–IV, and mixed phenotype were significant factors associated with severe exacerbation frequency in univariate analyses. Multivariate analyses showed that lower BMI and CT phenotype were significant factors associated with severe exacerbation frequency. Compared to the CT-normal phenotype, the mixed phenotype was significantly associated with more frequent severe exacerbation (IRR 4.134, 95% CI: 1.135–15.057, P=0.031).

Conclusion

Patients with mixed phenotype are more symptomatic, have poorer pulmonary function, and are associated with more frequent severe exacerbation.

CAT Score and SGRQ Definitions of Chronic Bronchitis as an Alternative to the Classical Definition

Purpose

Previous studies have used various definitions to classify chronic obstructive pulmonary disease (COPD) patients into chronic bronchitis (CB) and non-CB patients. This study was performed to identify differences among three definitions of CB based on the classical method, St. George's Respiratory Questionnaire (SGRQ), and the CAT (COPD Assessment Test) score.

Patients and methods

We extracted data from the multicenter Korea COPD Subgroup Study (KOCOSS) cohort, for which patients recruited from among 47 medical centers in South Korea beginning in April 2012. Patients were classified according to three different definitions of CB: 1) classical definition; 2) SGRQ (using questions regarding cough and sputum); and 3) CAT score (comprising cough [CAT1] and sputum [CAT2] subscale scores).

Results

A total of 2694 patients were enrolled in this study. The proportions of CB were 10.8%, 35.8%, and 24.0% according to the classical, SGRQ, and CAT definitions, respectively. The three definitions yielded consistently significant differences between CB and non-CB patients in modified Medical Research Council dyspnea scale CAT score, SGRQ score, number of moderate-to-severe exacerbations per year and forced expiratory volume in 1 second. By three definitions, CB consistently predicted future risk of exacerbation. The kappa coefficient of agreement between the classical definition and SGRQ definition was 0.29, that of the classical definition and CAT definition was 0.32, and that of the SGRQ definition and CAT definition was 0.44.

Conclusion

Patients with CB according to the new definitions based on SGRQ or CAT score showed similar clinical characteristics to those defined according to the classical definition. The new CB definitions may be used as alternatives to the classical definition.

Comparison of clinical baseline characteristics between Asian and Western COPD patients in a prospective, international, multicenter study

We aimed to compare clinical characteristics between Asian and Western chronic obstructive pulmonary disease (COPD) patients. This was a sub-analysis of an international, multicenter, prospective cohort study. Asian patients were enrolled in Singapore and South Korea. Western patients were enrolled in Spain, Poland, Ireland, the United Kingdom, and Malta. A total of 349 patients were analyzed. Among them, 110 (32%) patients were Asian and 239 (68%) Western. Male sex was more predominant in Asian than in Western (95% versus 63%, respectively; P<0.01). Body mass index was significantly lower in Asian (23.5 versus 27.1; P<0.01). The proportion of patients with a history of exacerbation was lower in Asian (12% versus 64%; P<0.01). Although patients were enrolled by same inclusion criteria, there were several differences between Asian and Western COPD patients. Our study has shown unbiased real-world differences between Asian and Western COPD patients. Since prospective follow-up study is currently ongoing, the result of this study can be fundamental base of future analysis.