BackgroundThe clinical phenotypes and underlying mechanisms of asthma-COPD overlap syndrome (ACOS) remain elusive. This study aimed to investigate a comparison of COPD patients with and without ACOS, focusing on inflammatory biomarkers, in an outpatient COPD cohort.MethodsWe conducted a cross-sectional study analyzing prospectively collected data from the Ishinomaki COPD Network registry. All participants were diagnosed with COPD, confirmed by using spirometry, and were aged 40–90 years and former smokers. Patients with features of asthma including both variable respiratory symptoms and variable expiratory airflow limitation were identified and defined as having ACOS. Then, the inflammatory biomarkers such as fractional exhaled nitric oxide level, blood eosinophil count and percentage, total immunoglobulin E (IgE) level, and presence of antigen-specific IgE were evaluated.ResultsA total of 257 patients with COPD were identified, including 37 (14.4%) with ACOS. Patients with ACOS tended to be younger, have a shorter smoking history, and use more respiratory medications, especially inhaled corticosteroids and theophylline. Mean fractional exhaled nitric oxide level was significantly higher in those with ACOS than in those without ACOS (38.5 parts per billion [ppb] vs 20.3 ppb, P<0.001). Blood eosinophil count and percentage were significantly increased in those with ACOS (295/mm3 vs 212/mm3, P=0.032; 4.7% vs 3.2%, P=0.003, respectively). Total IgE level was also significantly higher, and presence of antigen-specific IgE was observed more frequently in patients with ACOS. Receiver operating characteristic curve analysis indicated that the sensitivity and specificity of these biomarkers were relatively low, but combinations of these biomarkers showed high specificity for ACOS diagnosis.ConclusionThese results provide evidence that these inflammatory biomarkers can be used to support the diagnosis of ACOS.

ObjectiveTo investigate the impact in an aging society of the 2011 Great East Japan earthquake on hospitalisation for respiratory disease at the disaster base hospital.DesignDescriptive and cross-sectional study.SettingEmergency care in Japanese Red Cross Ishinomaki Hospital, a regional disaster base hospital in Miyagi, Japan.Participants322 emergency patients who were hospitalised for respiratory disease from 11 March to 9 May 2011, and 99 and 105 emergency patients who were hospitalised in the corresponding periods in 2009 and 2010, respectively.Main outcome measuresDescription and comparison of patient characteristics and disease distribution in terms of age, time after the disaster and activities of daily living (ADL).Results1769 patients were admitted to our hospital during the study period (compared to 850 in 2009 and 1030 in 2010), among whom 322 were hospitalised for respiratory disease (compared to 99 in 2009 and 105 in 2010). Pneumonia (n=190, 59.0%) was the most frequent cause of admission for pulmonary disease, followed by acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) (n=53, 16.5%), asthma attacks (n=27, 8.4%) and progression of lung cancer (n=22, 6.8%). Compared with the corresponding periods in 2009 and 2010, the increase in the absolute numbers of admissions was highest for pneumonia, followed by AE-COPD and asthma attacks. At hospitalisation, 195 patients were ‘dependent’ and 54 patients were ‘partially dependent’. Respiratory admissions accompanied by deterioration of ADL after the disaster were more frequent in elderly and female patients.ConclusionsAfter the Great East Japan Earthquake, admissions for pneumonia and exacerbation of chronic respiratory disease in the elderly increased at the disaster base hospital.

The large-scale natural disaster that hit Japan in 2011 had a serious negative impact on the clinical outcomes of COPD patients in the disaster-affected area.

PurposeThe GOLD report provides a framework for classifying COPD in a way that reflects its clinical impact and allows treatment recommendations. The GOLD 2017 proposes a new classification whereby patients are grouped as A–D according to their symptoms and history of exacerbations. However, the clinical characteristics and outcomes in these patients are not well documented.Patients and methodsIn this prospective observational study, we analyzed data from the Ishinomaki COPD Network Registry. All patients with stable COPD were classified into the four groups defined by GOLD 2017. The patient demographics, clinical characteristics, number of exacerbations, and mortality rate during 1 year of follow-up were compared between the groups.ResultsFour hundred and one patients with stable COPD were identified. There were 240 patients (59.9%) in group A, 122 (30.4%) in group B, 16 (4.0%) in group C, and 23 (5.7%) in group D. Patients in groups B, C, and D had ORs of 2.95, 3.92, and 5.45, respectively, for risk of exacerbation relative to group A. Groups C and D experienced exacerbations more frequently, including exacerbations leading to hospital admission, than groups A and B (both P<0.001) during the 1-year follow-up period. Patients with a high risk of exacerbation (groups C and D) had a lower body mass index, showed more symptoms, used more respiratory medications, and had more severe airflow limitation than patients at low risk of exacerbation (groups A and B). Mortality was not different between the high-risk and low-risk groups.ConclusionThe results of our study provide evidence that the GOLD 2017 classification identifies patients with COPD at risk of exacerbations, including those requiring hospitalization, but has a poor ability to predict mortality.

Smoking-related interstitial lung abnormalities are different from specific forms of fibrosing lung disease which might be associated with poor prognoses. Chronic obstructive pulmonary disease with comorbid interstitial lung abnormalities and that with pulmonary fibrosis are considered different diseases; however, they could share a common spectrum. We aimed to evaluate the clinical characteristics of Japanese patients with chronic obstructive pulmonary disease and comorbid interstitial lung abnormalities. In this prospective observational study, we analyzed data from the Ishinomaki COPD Network Registry. We evaluated the clinical characteristics of patients with chronic obstructive pulmonary disease with and without comorbid interstitial lung abnormalities by comparing the annualized rate of chronic obstructive pulmonary disease exacerbations per patient during the observational period. Among 463 patients with chronic obstructive pulmonary disease, 30 (6.5%) developed new interstitial lung abnormalities during the observational period. After 1-to-3 propensity score matching, we found that the annualized rate of chronic obstructive pulmonary disease exacerbations per patient during the observational period was 0.06 and 0.23 per year in the interstitial lung abnormality and control groups, respectively (P = 0.043). Our findings indicate slow progression of interstitial lung abnormality lesions in patients with pre-existing chronic obstructive pulmonary disease. Further, interstitial lung abnormality development did not significantly influence on chronic obstructive pulmonary disease exacerbation. We speculate that post-chronic obstructive pulmonary disease interstitial lung abnormalities might involve smoking-related interstitial fibrosis, which is different from specific forms of fibrosing lung disease associated with poor prognoses.