Prevalence of airflow limitation in outpatients with cardiovascular diseases in Japan

Nontuberculous mycobacterial pulmonary disease added burden to COPD and bronchiectasis in Japan

Background and objective

Nontuberculous mycobacterial pulmonary disease (NTM-PD) prevalence in Japan is among the highest worldwide. COPD and bronchiectasis are common comorbidities among patients with NTM-PD, and it is challenging to treat NTM-PD in patients with these conditions. There are limited data on the incremental burden that NTM-PD adds to underlying COPD or bronchiectasis in Japan. Therefore, the objective of this study was to assess the incremental burden associated with NTM-PD in patients with pre-existing COPD and/or bronchiectasis.

Methods

This nested case-control study was based on JMDC, Inc. claims data (2015-2020). Patients with COPD and/or bronchiectasis with NTM-PD (cases) were age and sex matched 1:3 to patients with COPD and/or bronchiectasis without NTM-PD (controls), resulting in three mutually exclusive patient groups (COPD, bronchiectasis or both; with or without NTM-PD). Incremental burden of NTM-PD was assessed within each group by comparing hospitalisations during the 1-year period after NTM-PD diagnosis (index) between cases and controls with both univariate analysis and multivariate analysis adjusting for pre-index comorbidities.

Results

Univariate analyses in the three patient groups consistently demonstrated incremental hospitalisation burden in cases versus controls (e.g. COPD group: 20% of 492 cases versus 13% of 1476 controls had all-cause hospitalisations; 11% versus 5% had respiratory-related hospitalisations; and 6% versus 2% had COPD-related hospitalisations). Subsequent multivariate analysis further confirmed the findings.

Conclusions

The substantial incremental burden of hospitalisation associated with NTM-PD in patients with COPD and/or bronchiectasis highlights the urgent need for appropriate management of NTM-PD in Japan.

Development of a Communication Tool between Patients and Physicians for Recognizing COPD Exacerbations in Japan

In Japan, exacerbations are underreported compared with other countries, possibly due in part to a failure to recognize them. This study aimed to create a simple chronic obstructive pulmonary disease (COPD) Exacerbation Recognition Tool (CERT-J) specifically for Japanese patients. Patients ≥40 years with confirmed COPD or asthma-COPD overlap were included. Focus groups were held to identify words and phrases used by patients to describe symptoms associated with an exacerbation, resulting in candidate items being identified. Following cognitive debriefing, the items were refined based on item frequency, level of endorsement and effect of demographic factors. Exploratory factor analysis (EFA) was then performed to inform an expert panel's choice of items to form the new tool. A total of 41 patients were included in the focus groups and nine patients performed the cognitive debrief. Following this, the expert panel identified 26 items for testing in a further 100 patients (mean age 72 years, forced expiratory volume in 1 s 54.8% predicted and 1.8 exacerbations in the preceding 12 months). Eleven items were associated with breathlessness or activity limitation and seven of these were the most frequently endorsed. EFA identified four factors, with one (breathlessness) being dominant. The expert panel recommended that the CERT-J should include six items: breathlessness and activity limitation (3 items), cough (1 item) and phlegm (2 items). The final CERT-J should benefit patients with COPD by providing them with an increased understanding and recognition of exacerbations.Clinical Trial Registration: GSK K.K (jRCT1080224526).

Obstructive Sleep Apnea in Patients with Chronic Obstructive Pulmonary Disease: Facts and Perspectives

The co-occurrence of obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) in the same patient, named the overlap syndrome (OS), was first described in 1985. Although the American Thoracic Society underlined the limited knowledge of OS, stated research priorities for this condition, and recommended a "screening" strategy to identify OSA in COPD patients with chronic stable hypercapnia, research studies on OS remain scarce. This review aims to summarize the current knowledge and perspectives related to OSA in COPD patients. OS prevalence is 1.0-3.6% in the general population, 3-66% in COPD patients, and 7-55% in OSA patients. OS patients may have worse sleep quality than those with OSA or COPD alone. Scoring hypopneas may be difficult in COPD patients; desaturation episodes may have origins in these patients, namely upper airway obstruction, hypoventilation during paradoxical sleep, ventilation/perfusion mismatches, and obesity. The apnea-hypopnea index is similar in OSA and OS patients. Desaturations may be greater and more prolonged in OS patients than in patients with COPD or OSA alone. Low body mass index, hyperinflation, and less collapsible airways reduce the risk of OSA in COPD patients. OSA is a risk factor for pulmonary hypertension in COPD patients. Whether OS increases mortality and morbidity risks compared to COPD or OSA alone remains to be confirmed. No guidelines currently recommend specific approaches to the treatment of OSA in patients with COPD.

Narrative review of current COPD status in Japan

Chronic obstructive pulmonary disease (COPD) causes morbidity and mortality worldwide. Due to the improvement in environmental sanitation and medical care, the general life span has increased in the past decades in Japan. However, many older patients with COPD develop a wide range of comorbidities, and the impairments in the activities of daily living result in frailty and increase social and economic burdens. Population-based studies have shown that the prevalence of COPD is approximately 10% among subjects aged ≥40 years, but more than 80% of COPD patients are underdiagnosed. The Ministry of Health, Labour, and Welfare in Japan proposed the National Health Promotion in the 21st century, termed Health Japan 21 (the second term), in 2013 to prevent the onset and progression of noncommunicable diseases (NCDs), including COPD. The government, medical society, and community have been attempting to increase the recognition of COPD and promote smoking cessation. Additionally, Japanese cohorts have revealed distinct clinical features in Japanese patients with COPD, including lower rates of patient-reported exacerbations, less frequent coexisting cardiovascular disease and metabolic syndrome, and lower use of inhaled corticosteroids in Japan compared to the Western countries. Moreover, the poor adherence to inhaled medications is found in approximately 20% of subjects, and rehabilitation is performed in 26% of hospitalized patients with COPD. Therefore, more efforts should be made to improve adherence and access to pulmonary rehabilitation. Overall, Japanese COPD patients share common clinical and social features with COPD patients in other countries. Further international corroboration may help establish better comprehensive management of the disease.

Association Between Airflow Limitation and Carotid Intima-Media Thickness in the Japanese Population

PURPOSE

This study aimed to reveal the association between airflow limitation (AL) and carotid intima-media thickness (IMT) according to smoking status in Japan.

SUBJECTS AND METHODS

This cross-sectional study was performed in 2809 subjects, who underwent a comprehensive health examination with pulmonary function tests and carotid ultrasonographic measurement. AL was defined as forced expiratory volume in 1 s/forced vital capacity of <0.7. The subjects were divided into the following four groups: never smokers without AL, never smokers with AL, former/current smokers without AL, and former/current smokers with AL. Mean IMT, the maximum measurable IMT value in the left and right common carotid arteries (IMT-C max), and mean IMT-C max were measured by carotid ultrasonography. The carotid wall thickness as defined as follows: IMT ≥ 1.1 mm (IMT1.1), IMT-C max ≥ 1.2 mm (IMTc1.2), and IMT-C max > 1.5 mm (IMTc1.5), based on each measured region. The association between AL and the carotid wall thickness according to smoking status was assessed by logistic regression analysis.

RESULTS

The mean carotid IMT and mean IMT-C max were significantly higher in never smokers with AL and former/current smokers with or without AL than in never smokers without AL. In logistic regression models adjusted for sex, age, body mass index, hypertension, dyslipidemia, hyperglycemia, physical activity, and alcohol consumption, the risk of carotid wall thickness (IMT1.1 [odds ratio {OR}: 1.55; 95% confidence interval {CI}: 1.07-2.24]; IMTc1.2 [OR: 1.52; 95% CI: 1.03-2.24]; IMTc1.5 [OR: 1.99; 95% CI: 1.15-3.46]) were significantly higher in former/current smokers with AL than in never smokers without AL.

CONCLUSION

The present results suggest that greater IMT and risk of carotid wall thickness were associated with AL and smoking experience.

Motor Pathophysiology Related to Dyspnea in COPD Evaluated by Cardiopulmonary Exercise Testing

In chronic obstructive pulmonary disease (COPD), exertional dyspnea, which increases with the disease’s progression, reduces exercise tolerance and limits physical activity, leading to a worsening prognosis. It is necessary to understand the diverse mechanisms of dyspnea and take appropriate measures to reduce exertional dyspnea, as COPD is a systemic disease with various comorbidities. A treatment focusing on the motor pathophysiology related to dyspnea may lead to improvements such as reducing dynamic lung hyperinflation, respiratory and metabolic acidosis, and eventually exertional dyspnea. However, without cardiopulmonary exercise testing (CPET), it may be difficult to understand the pathophysiological conditions during exercise. CPET facilitates understanding of the gas exchange and transport associated with respiration-circulation and even crosstalk with muscles, which is sometimes challenging, and provides information on COPD treatment strategies. For respiratory medicine department staff, CPET can play a significant role when treating patients with diseases that cause exertional dyspnea. This article outlines the advantages of using CPET to evaluate exertional dyspnea in patients with COPD.

COPD prevalence in smokers with stable ischemic heart disease: A cross-sectional study in Tunisia

BACKGROUND

Chronic obstructive pulmonary disease (COPD) and ischemic heart disease (IHD) are common causes of mortality worldwide, with shared risk factors. COPD continues to be largely underdiagnosed and undertreated, especially in patients with IHD.

OBJECTIVE

To investigate the prevalence of COPD in smokers with confirmed IHD and to compare IHD characteristics between COPD patients and those without COPD.

METHODS

It was a cross-sectional study, conducted between August and December 2017, including patients over 40 years of age, current or former smokers, with stable and confirmed IHD. Spirometry was undertaken for all participants, and COPD was defined according to GOLD criteria.

RESULTS

A total of 122 patients, with mean age of 59.3 years and mean pack-year of 52.3, were enrolled. Spirometry was normal in 63.2% of patients and airflow limitation was the most frequent ventilatory disorder (20.5%). COPD was diagnosed in 19.7% of patients. Of the 24 COPD patients, 17 (70.8%) were previously undiagnosed. Airflow limitation severity in COPD patients was classified mild, moderate, severe and very severe in 25%, 62.5%, 8.3% and 4.2% of patients. Comparison between COPD patients and non-COPD patients showed that comorbidities, respiratory symptoms, chest x-ray abnormalities, life-threatening lesions, three vessel disease, pulmonary hypertension and right ventricle dysfunction were significantly more frequent in COPD patients.

CONCLUSIONS

There was a high prevalence of COPD among smoking patients with IHD, and most were undiagnosed despite being symptomatic. Smokers with IHD, especially if having respiratory symptoms, radiological or ultrasound abnormalities or life-threatening coronary lesions should be evaluated for airflow limitation.

Management of cardiovascular comorbidities in chronic obstructive pulmonary disease patients

Chronic obstructive pulmonary disease (COPD) is а highly prevalent, complex and heterogeneous clinical condition which is associated with significant concomitant diseases. COPD and cardiovascular diseases (CVDs) often coexist due to the high prevalence of each of these pathological conditions separately as well as the common risk factors (particularly smoking), mechanisms of interaction and influence of systemic inflammation. In addition, decreased pulmonary function in COPD is closely associated with an increased risk of congestive CVDs. One of the most important pathophysiological markers of COPD—lung hyperinflation—plays a significant role in the appearance of functional limitations of the pumping function of the heart, creating unfavorable conditions by exerting a compression effect on the heart muscle. The latter was confirmed by significant correlation between the COPD severity according to GOLD classification and the basic dimensions of the heart chambers. Several decades ago, the term “microcardia” was commonly used and indicated a radiological sign of emphysema. Some studies demonstrated a close relationship between the chance of occurrence of CVD and the severity of pulmonary dysfunction. Such an association has been demonstrated for the whole spectrum of CVD—including cerebrovascular disease, congestive heart failure (CHF) and rhythm disturbances—and was detected in the early stages of the disease. A large proportion of patients with mild and moderate COPD die due to CVD, which is much more likely than deaths in the same group due to respiratory insufficiency. COPD patients have a higher rate of hospitalization and death, the cause of which are coronary heart disease (CHD), stroke and CHF. Treatment of COPD today is mainly determined by national and international clinical guidelines, which should pay more attention to the problems of the treatment of COPD patients with comorbid conditions.

Prevalence and Baseline Clinical Characteristics of Eosinophilic Chronic Obstructive Pulmonary Disease: A Meta-Analysis and Systematic Review

Background: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease with different clinical and pathophysiological characteristics. Cumulative evidence shows that eosinophil levels may be connected to the therapeutic effects and phenotype of COPD. However, the prevalence of eosinophilic inflammation in COPD and the baseline characteristics of eosinophilic COPD remain unknown. Our study investigated the prevalence of COPD with eosinophil levels of >2% and the characteristics of eosinophilic COPD. Methods: We searched the Cochrane Central Library, Medline, Embase, and the Web of Science for trials of eosinophil and COPD published from database inception to May 1, 2019. Results: In total, 40,112 COPD patients that were involved in 19 trials were included in the final analysis. The prevalence of eosinophilic COPD ranged from 18.84 to 66.88%, with an average prevalence of 54.95% across all studies. We found that men, ex-smokers, individuals with a history of ischemic heart disease, and individuals with a higher body mass index (BMI) were at higher risk of eosinophilic COPD (OR 1.36, 95% CI 1.26-1.46, P < 0.00001; OR 1.23, 1.12-1.34, P < 0.0001; OR 1.31, 1.14-1.50, P = 0.001; MD 0.70, 0.27-1.12, P = 0.001). There was, however, a lower proportion of GOLD stage I patients among those with eosinophilic COPD (OR 0.84, 0.73-0.96, P = 0.01). No significant differences were found in terms of age, current smoker status, pack-years smoked, percent of predicted forced expiratory volume in 1 s, hypertension, diabetes, or other GOLD stages between the two groups (P > 0.05). Conclusions: Our analysis suggests that eosinophilic inflammation is prevalent in COPD. Eosinophilic COPD was more likely to occur in men, ex-smokers, those with a higher BMI, and those with a high risk of some comorbidity; however, a lower proportion of patients with eosinophilic COPD experienced mild airflow limitations.

[Chronic obstructive pulmonary disease and cardiovascular comorbidity]

In recent years, a greater understanding of the heterogeneity and complexity of chronic obstructive pulmonary disease (COPD) has come from the point of view of an integrated clinical assessment of severity, pathophysiology, and the relationship with other pathologies. A typical COPD patient suffers on average 4 or more concomitant diseases and every day about a third of patients take from 5 to 10 different drugs. The mechanisms of the interaction of COPD and cardiovascular disease (CVD) include the effects of systemic inflammation, hyperinflation (hyperinflation) of the lungs and bronchial obstruction. The risk of developing CVD in patients with COPD is on average 2-3 times higher than in people of a comparable age in the general population, even taking into account the risk of smoking. The prevalence of coronary heart disease, heart failure, and rhythm disturbances among COPD patients is significantly higher than in the general population. The article discusses in detail the safety of prescribing various groups of drugs for the treatment of CVD in patients with COPD. Achieving success in understanding and managing patients with COPD and CVD is possible using an integrated multidisciplinary approach.

Prevalence of undiagnosed COPD in male patients with coronary artery disease: a cross-sectional study in Jordan

Purpose

COPD and coronary artery disease (CAD) are common chronic diseases with shared risk factors. COPD continues to be largely underdiagnosed and undertreated. We aimed to describe the prevalence and predictors of undiagnosed COPD in Jordanian men with CAD.

Patients and methods

In a cross-sectional study conducted at a referral center in Jordan, male patients who underwent coronary angiography for suspected CAD and reported ≥10 pack-year of cigarette smoking were recruited. Pre- and post-bronchodilator spirometry was undertaken for all participants, and COPD was defined as post-bronchodilator FEV₁/FVC <70%. The finding of ≥50% coronary luminal narrowing confirmed the presence of CAD.

Results

Spirometry was undertaken for 376 men with mean age of 56.02±10.55 years, and 72.6% were active cigarettes smokers with a mean pack-year of 55.89±34.25. A CAD diagnosis was confirmed in 300 (79.8%) men. Spirometric criteria for COPD were met in 76 (15.7%) patients, of whom 91.5% were not previously diagnosed. COPD-related symptoms were common: chronic cough (44.4%), dyspnea (66.2%), and wheezes (27.9%). COPD was more common in patients with (18.0%) compared to patients without (6.6%) CAD (P=0.014). Multivariate logistic regression showed that the risk of COPD was higher in patients with CAD (OR 3.16, 95% CI, 1.10–9.09, P=0.033) and in those with chronic bronchitis (OR 13.07, 95% CI, 6.69–25.52, P<0.001).

Conclusion

There was a high prevalence of COPD among male patients with CAD and most were underdiagnosed despite having respiratory symptoms. Male smokers with CAD and respiratory symptoms should be evaluated for airflow limitation and the presence of COPD.

The distribution of blood eosinophil levels in a Japanese COPD clinical trial database and in the rest of the world

Background

Blood eosinophil measurements may help to guide physicians on the use of inhaled corticosteroids (ICS) for patients with chronic obstructive pulmonary disease (COPD). Emerging data suggest that COPD patients with higher blood eosinophil counts may be at higher risk of exacerbations and more likely to benefit from combined ICS/long-acting beta₂-agonist (LABA) treatment than therapy with a LABA alone. This analysis describes the distribution of blood eosinophil count at baseline in Japanese COPD patients in comparison with non-Japanese COPD patients.

Methods

A post hoc analysis of eosinophil distribution by percentage and absolute cell count was performed across 12 Phase II–IV COPD clinical studies (seven Japanese studies [N=848 available absolute eosinophil counts] and five global studies [N=5,397 available eosinophil counts] that included 246 Japanese patients resident in Japan with available counts). Blood eosinophil distributions were assessed at baseline, before blinded treatment assignment.

Findings

Among Japanese patients, the median (interquartile range) absolute eosinophil count was 170 cells/mm³ (100–280 cells/mm³). Overall, 612/1,094 Japanese patients (56%) had an absolute eosinophil count ≥150 cells/mm³ and 902/1,304 Japanese patients (69%) had a percentage eosinophil ≥2%. Among non-Japanese patients, these values were 160 (100–250) cells/mm³, 2,842/5,151 patients (55%), and 2,937/5,155 patients (57%), respectively. The eosinophil distribution among Japanese patients was similar to that among non-Japanese patients. Within multi-country studies with similar inclusion criteria, the eosinophil count was numerically lower in Japanese compared with non-Japanese patients (median 120 vs 160 cells/mm³).

Interpretation

The eosinophil distribution in Japanese patients seems comparable to that of non-Japanese patients; although within multi-country studies, there was a slightly lower median eosinophil count for Japanese patients compared with non-Japanese patients. These findings suggest that blood eosinophil data from global studies are of relevance in Japan.

Early Detection of Chronic Obstructive Pulmonary Disease in Primary Care

Objective To evaluate the effectiveness of an early detection program for chronic obstructive pulmonary disease (COPD) in a primary care setting in Japan. Methods Participants of ≥40 years of age who regularly visited a general practitioner's clinic due to chronic disease were asked to complete a COPD screening questionnaire (COPD Population Screener; COPD-PS) and undergo simplified spirometry using a handheld spirometric device. Patients who showed possible COPD were referred to a respiratory specialist and underwent a detailed examination that included spirometry and chest radiography. Results A total of 111 patients with possible COPD were referred for close examination. Among these patients, 27 patients were newly diagnosed with COPD. The patients with COPD were older, had lower BMI values, and had a longer smoking history in comparison to non-COPD patients. COPD patients also had more comorbid conditions. A diagnosis of COPD was significantly associated with a high COPD-PS score (p<0.001) and the detection of possible airflow limitation evaluated by the handheld spirometric device (p<0.01). An ROC curve analysis demonstrated that 5 points was the best COPD-PS cut-off value for the diagnosis of COPD. The combination of both tools showed 40.7% of sensitivity and 96.4% of specificity. Conclusion The use of the COPD-PS plus a handheld spirometric device could facilitate the early detection of undiagnosed COPD in primary care.

Small airway dysfunction in smokers with stable ischemic heart disease

BACKGROUND

A higher prevalence of airflow limitation (AL) has been described in patients with ischemic heart disease (IHD). Although small airway dysfunction (SAD) is an early feature of AL, there is little information about its occurrence in IHD patients. Our objective was to describe the prevalence of SAD in IHD patients, while comparing patient-related outcomes and future health risk among IHD patients with AL, SAD and normal lung function.

METHODS

In 118 consecutive smoking patients with stable IHD, comorbidities, utilization of healthcare resources, current treatment, blood biochemistry and health status were recorded. SAD was evaluated by impulse oscillometry, and pre- and post-bronchodilator spirometry was performed.

RESULTS

The prevalence of AL and SAD were 20.3 (95% CI, 13.1-27.6%) and 26.3% (95% CI, 18.3-34.2%), respectively. Compared to the normal lung function group, patients with SAD and without AL had lower spirometric values, poorer quality of life and higher levels of C-reactive protein (CRP), as well as increased cardiovascular risk and more vascular age. In patients with normal spirometry, the presence of SAD was independently associated with pack-years, HDL-cholesterol and CRP levels.

CONCLUSION

In patients with IHD, the presence of SAD is common and that it is associated with reduced health status and increased future cardiac risk.

Total management of chronic obstructive pulmonary disease (COPD) as an independent risk factor for cardiovascular disease

Patients with cardiovascular disease (CVD) often have multiple comorbid conditions that may interact with each other, confound the choice of treatments, and reduce mortality. Chronic obstructive pulmonary disease (COPD) is one of the most important comorbidities of CVD, which causes serious consequences in patients with ischemic heart disease, stroke, arrhythmia, and heart failure. COPD shares common risk factors such as tobacco smoking and aging with CVD, is associated with less physical activity, and produces systemic inflammation and oxidative stress. Overall, patients with COPD have a 2-3-fold increased risk of CVD as compared to age-matched controls when adjusted for tobacco smoking. Chronic heart failure (HF) is a frequent and important comorbidity which has a significant impact on prognosis in COPD, and vice versa. HF overlaps in symptoms and signs and has a common comorbidity with COPD, so that diagnosis of COPD is difficult in patients with HF. The combination of HF and COPD presents many therapeutic challenges including beta-blockers (BBs) and beta-agonists. Inhaled long-acting bronchodilators including beta2-agonists and anticholinergics for COPD would not worsen HF. Diuretics are relatively safe, and angiotensin-converting enzyme inhibitors are preferred to treat HF accompanied with COPD. BBs are only relatively contraindicated in asthma, but not in COPD. Low doses of cardioselective BBs should be aggressively initiated in clinically stable patients with HF accompanied with COPD combined with close monitoring for signs of airway obstruction and gradually up-titrated to the maximum tolerated dose. Encouraging appropriate and aggressive treatment for both HF and COPD should be recommended to improve quality of life and mortality in HF patients with COPD.

Impact of airflow limitation in chronic heart failure

Background

Comorbidities are common in chronic heart failure (HF) patients, but diagnoses are often not based on objective testing. Chronic obstructive pulmonary disease (COPD) is an important comorbidity and often neglected because of shared symptoms and risk factors. Precise prevalence and consequences are not well known. Therefore, we investigated prevalence, pulmonary treatment, symptoms and quality of life (QOL) of COPD in patients with chronic HF.

Methods

205 patients with stable HF for at least 1 month, aged above 50 years, were included from our outpatient cardiology clinic, irrespective of left ventricular ejection fraction. Patients performed post-bronchodilator spirometry, a six-minute walk test (6-MWT) and completed the Kansas City Cardiomyopathy Questionnaire (KCCQ). COPD was diagnosed according to GOLD criteria. Restrictive lung function was defined as FEV₁/FVC ≥0.70 and FVC <80% of predicted value. The BODE and ADO index, risk scores in COPD patients, were calculated.

Results

Almost 40% fulfilled the criteria of COPD and 7% had restrictive lung disease, the latter being excluded from further analysis. Noteworthy, 63% of the COPD patients were undiagnosed and 8% of those without COPD used inhalation therapy. Patients with COPD had more shortness of breath despite little difference in HF severity and similar other comorbidities. KCCQ was significantly worse in COPD patients. The ADO and BODE indices were significantly different.

Conclusion

COPD is very common in unselected HF patients. It was often not diagnosed and many patients received treatment without being diagnosed with COPD. Presence of COPD worsens symptoms and negatively effects cardiac specific QOL.

Cut-off value of FEV1/FEV6 as a surrogate for FEV1/FVC for detecting airway obstruction in a Korean population

Background

Forced expiratory volume in 1 second (FEV₁)/forced expiratory volume in 6 seconds (FEV₆) has been proposed as an alternative to FEV₁/forced vital capacity (FVC) for detecting airway obstruction. A fixed cut-off value for FEV₁/FEV₆ in a Korean population is lacking. We investigated a fixed cut-off for FEV₁/FEV₆ as a surrogate for FEV₁/FVC for detecting airway obstruction.

Materials and methods

We used data obtained in the 5 years of the Fifth and Sixth Korean National Health and Nutrition Examination Survey. A total of 14,978 participants aged ≥40 years who underwent spirometry adequately were the study cohort. “Airway obstruction” was a fixed cut-off FEV₁/FVC <70% according to the Global Initiative for Chronic Obstructive Lung Disease guidelines. We also used European Respiratory Society/Global Lung Initiative 2012 equations for the FEV₁/FVC lower limit of normal.

Results

Among the 14,978 participants (43.5% male, 56.5% female; mean age: 56.9 years for men and 57.0 years for women), 14.0% had obstructive lung function according to a fixed cut-off FEV₁/FVC <70%. Optimal FEV₁/FEV₆ cut-off for predicting FEV₁/FVC <70% was 75% using receiver operating characteristic curve analyses (area under receiver operating characteristic curve =0.989, 95% confidence interval 0.987–0.990). This fixed cut-off of FEV₁/FEV₆ showed 93.8% sensitivity, 94.8% specificity, 74.7% positive predictive value, 98.9% negative predictive value, and 0.8 Cohen’s kappa coefficient. When compared with FEV₁/FVC < lower limit of normal, FEV₁/FEV₆ <75% tended to over-diagnose airflow limitation (just like a fixed cut-off of FEV₁/FVC <70%). When grouped according to age and FEV₁ (%), FEV₁/FEV₆ <75% diagnosed more airway obstruction in older participants and mild–moderate stages compared with FEV₁/FVC <70%.

Conclusion

A valid fixed cut-off for detecting airway obstruction in a Korean population is FEV₁/FEV₆ of 75%, but should be used with caution in older individuals and those with mild–moderate airway obstruction.

Prevalence of airflow limitation in subjects undergoing comprehensive health examination in Japan: Survey of Chronic Obstructive pulmonary disease Patients Epidemiology in Japan

Purpose

There are still evidence gaps on the prevalence of airflow limitation in Japan. The purpose of this survey was to estimate the prevalence of airflow limitation among healthy subjects in Japan and to show what proportion of subjects with airflow limitation had been diagnosed with chronic obstructive pulmonary disease (COPD).

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 from 14 centers in Japan. Airflow limitation was defined as having forced expiratory volume in 1 second/forced vital capacity less than 70%.

Results

In a total of 22,293 subjects, airflow limitation was most prevalent in subjects aged over 60 years (8.7%), but was also observed in subjects aged 50–59 years (3.1%) and 40–49 years (1.7%). Overall prevalence was 4.3%. Among subjects with smoking history (n=10,981), the prevalence of airflow limitation in each age group (12.8% in those aged over 60 years, 4.4% in those aged 50–59 years, and 2.2% in those aged 40–49 years) and overall prevalence (6.1%) were higher than that of total subjects. Of the smokers with airflow limitation, 9.4% had been diagnosed with COPD/emphysema and 27.3% with other respiratory diseases.

Conclusion

Among smokers undergoing comprehensive health examination, prevalence of airflow limitation reached 12.8% in those aged over 60 years and airflow limitation was observed in subjects aged 40–59 years as well, though their prevalence was lower than that in subjects aged over 60 years. We demonstrated that a significant proportion of smokers with airflow limitation had not been diagnosed with COPD/emphysema, suggesting that some of them can be diagnosed with COPD or other respiratory diseases by a detailed examination after comprehensive health examination. Screening for subjects at risk of COPD by spirometry in comprehensive health examination starting at 40 years of age, followed by a detailed examination, may be an effective approach to increase the diagnosis of COPD.

Prevalence, awareness, characteristics, and health outcomes associated with COPD at-risk status among adults in Japan

OBJECTIVES

We examined the prevalence of chronic obstructive pulmonary disease (COPD) diagnosed and at-risk status, and public awareness of COPD among adults in Japan, as well as respondent characteristics and health outcomes compared with controls.

METHODS

Regression models used 2012 National Health and Wellness Survey in Japan data to compare COPD-diagnosed, at-risk, and healthy adults (aged ≥18) on demographics, health behaviors, health-related quality of life (HRQoL), productivity and healthcare resource use.

RESULTS

Among n = 29,978 respondents, diagnosed COPD prevalence was 0.9%; 26.9% were at-risk. Relative to controls, those at-risk and diagnosed with COPD had significantly greater healthcare resource use, with lower productivity and HRQoL. Fewer than 20% of respondents were aware of COPD.

CONCLUSIONS

Over 25% of adult Japanese respondents were at-risk for COPD and had health outcomes impairments relative to controls. Efforts to increase awareness among the general public are needed.

Associations of lifelong cigarette consumption and hypertension with airflow limitation in primary care clinic outpatients in Japan

BACKGROUND

Underdiagnosis is a critical problem in the management of chronic obstructive pulmonary disease (COPD). It is important to screen patients at risk for COPD among those with lifestyle-related diseases such as hypertension, diabetes mellitus, and dyslipidemia, since these diseases promote the development of cardiovascular diseases closely associated with increased COPD mortality.

METHODS

Thirteen primary care clinics in a suburb of Tokyo participated in the current study. A total of 950 patients from these clinics were enrolled in the study between 2010 and 2012; the patients ranged in age from 40 to 79 years, and they had no diagnosed respiratory diseases at the time of enrollment. Patients fulfilling the selection criteria were recruited to undergo spirometry and then completed a self-report questionnaire about comorbid diseases and smoking habits. Spirometry was performed 15 min after inhalation of 200 μg of salbutamol sulfate.

RESULTS

The prevalence of airflow limitation was 12.7% in the 950 primary care clinic patients. Lifelong cigarette consumption was the most significant risk factor for airflow limitation, e.g., patients who smoked 60 pack-years or more had a 40% likelihood of airflow limitation. Among common lifestyle-related diseases, hypertension was associated with the severity of airflow limitation (p=0.03), whereas dyslipidemia appeared to be inversely correlated with the severity of airflow limitation (p=0.004) on multiple regression analysis including lifelong cigarette consumption as a factor.

CONCLUSIONS

Undiagnosed airflow limitation was detected in 12.7% of outpatients at the primary care clinics. Since most patients with lifestyle-related diseases are treated by primary care physicians, it is essential for the physicians to obtain an accurate history of smoking and comorbid diseases to screen patients for COPD.

Prevalence of chronic obstructive pulmonary disease among patients with systemic arterial hypertension without respiratory symptoms

BACKGROUND

The diagnosis of chronic obstructive pulmonary disease (COPD) is often delayed until later stages of the disease. The purpose of the present study was to determine the prevalence of COPD among adults on treatment for systemic arterial hypertension independently of the presence of respiratory symptoms.

METHODS

This cross-sectional study included adults aged ≥40 years with tobacco/occupational exposure and systemic arterial hypertension diagnosed at three Primary Health Care facilities in Goiania, Brazil. Patients were evaluated using a standardized respiratory questionnaire and spirometry. COPD prevalence was measured considering the value of forced vital capacity and/or forced expiratory volume in 1 second <0.70.

RESULTS

Of a total of 570 subjects, 316 (55%) met inclusion criteria and were invited to participate. Two hundred and thirty-three (73.7%) patients with arterial hypertension reported at least one respiratory symptom, while 83 (26.3%) reported no respiratory symptoms; 41 (17.6%) patients with arterial hypertension and at least one respiratory symptom, and 10 (12%) patients with arterial hypertension but no respiratory symptoms were diagnosed with COPD (P=0.24). The prevalence of COPD in people with no previous COPD diagnosis was greater among those with no respiratory symptoms (100%) than among those with respiratory symptoms (56.1%) (P=0.01).

CONCLUSION

Our findings suggest that regardless of the presence of respiratory symptoms, individuals aged ≥40 years with tobacco/occupational exposure and arterial hypertension may benefit from spirometric evaluation.

LAMA/LABA vs ICS/LABA in the treatment of COPD in Japan based on the disease phenotypes

In the combined use of bronchodilators of different classes, ie, long-acting β2-agonists (LABAs) and long-acting muscarinic antagonists (LAMAs), bronchodilation is obtained both directly, through LABA-mediated stimulation of β2-adrenergic receptors, and indirectly, through LAMA-mediated inhibition of acetylcholine action at muscarinic receptors. The clinical trial data for LABAs/LAMAs in the treatment of chronic obstructive pulmonary disease (COPD) continue to be promising, and these combinations will provide the convenience of delivering the two major bronchodilator classes, recommended as first-line maintenance options in COPD treatment guidelines. COPD is a complex condition that has pulmonary and extrapulmonary manifestations. These clinical manifestations are highly variable, and several are associated with different responses to currently available therapies. The concept of a COPD phenotype is rapidly evolving from one focusing on the clinical characteristics to one linking the underlying biology to the phenotype of the disease. Identification of the peculiarities of the different COPD phenotypes will permit us to implement a more personalized treatment in which the patient's characteristics, together with his or her genotype, will be key to choosing the best treatment option. At present in Japan, fixed combinations of inhaled corticosteroids (ICSs) and LABAs are frequently prescribed in the earlier stages of COPD. However, ICSs increase the risk of pneumonia. Notably, 10%-30% of patients with COPD with or without a history of asthma have persistent circulating and airway eosinophilia associated with an increased risk of exacerbations and sensitivity to steroids. Thus, sputum or blood eosinophil counts might identify a subpopulation in which ICSs could have potentially deleterious effects as well as a subpopulation that benefits from ICSs. In this review, I propose one plausible approach to position ICSs and LABAs/LAMAs in clinical practice, based on both the extent of airflow obstruction and the presence of an asthma component or airway eosinophilic inflammation. This approach is a tentative move toward personalized treatment for COPD patients, and with progress in knowledge and developments in physiology, lung imaging, medical biology, and genetics, identification of COPD phenotypes that provide prognostic and therapeutic information that can affect clinically meaningful outcomes is an urgent medical need.

The relationship between the COPD Assessment Test score and airflow limitation in Japan in patients aged over 40 years with a smoking history

BACKGROUND

A large number of chronic obstructive pulmonary disease (COPD) patients in Japan remain undiagnosed, primarily due to the underuse of spirometry. Two studies were conducted to see whether the COPD Assessment Test (CAT) in primary care has the potential to identify those patients who need spirometry for a diagnosis of COPD and to determine whether patients with cardiovascular disease had airflow limitation, which could be detected by CAT.

MATERIALS AND METHODS

Two multicenter, noninterventional, prospective studies (studies 1 and 2) were conducted across Japan. Patients in both studies were ≥40 years old with a smoking history. Those in study 1 were seen in primary care and had experienced repeated respiratory tract infections, but had no diagnosis of COPD. Patients in study 2 were identified in cardiovascular disease clinics when routinely visiting for their cardiovascular disease. All patients completed the CAT prior to lung-function testing by hand-held spirometry. The presence of airflow limitation was defined as a forced expiratory volume in 1 second (FEV1)/FEV6 ratio<0.73.

RESULTS

A total of 3,062 subjects completed the CAT (2,067 in study 1, 995 in study 2); 88.8% were male, and the mean age (±standard deviation) was 61.5±11.6 years. Airflow limitation was found in 400 (19.4%) patients in study 1, and 269 (27.0%) in study 2. The CAT score in patients with airflow limitation was significantly higher than in patients without airflow limitation in both studies: 8.6 (95% confidence interval [CI] 7.9-9.2) versus 7.4 (95% CI 7.1-7.6) in study 1, and 8.3 (95% CI 7.5-9.2) versus 6.4 (95% CI 6.0-6.8) in study 2 (both P<0.001).

CONCLUSION

These findings suggest that the CAT has the potential to identify patients with cardiovascular disease or a history of frequent chest infections who need spirometry to diagnose COPD.