Prevalence and causes of chronic cough in Japan.

BACKGROUND: Chronic cough is one of the most common symptoms of respiratory diseases and can adversely affect patients' quality of life and interfere with social activities, resulting in a significant social burden. A survey is required to elucidate the frequency and treatment effect of chronic cough. However, clinical studies that cover all of Japan have not yet been conducted. METHODS: Patients who presented with a cough that lasted longer than 8 weeks and visited the respiratory clinics or hospitals affiliated with the Japan Cough Society during the 2-year study period were registered. RESULTS: A total of 379 patients were enrolled, and those who did not meet the definition of chronic cough were excluded. A total of 334 patients were analyzed: 201 patients had a single cause, and 113 patients had two or more causes. The main causative diseases were cough variant asthma in 92 patients, sinobronchial syndrome (SBS) in 36 patients, atopic cough in 31 patients, and gastroesophageal reflux (GER)-associated cough in 10 patients. The time required to treat undiagnosed patients and those with SBS was significantly longer and the treatment success rate for GER-associated cough was considerably poor. CONCLUSIONS: We confirmed that the main causes of chronic cough were cough variant asthma, SBS, atopic cough, and their complications. We also showed that complicated GER-associated cough was more likely to become refractory. This is the first nationwide study in Japan of the causes and treatment effects of chronic cough.

Multiple anomalous systemic-pulmonary connections and coronary-pulmonary artery fistula associated with large aneurysms in an elderly woman.

We report the repair of a coronary artery fistula arising from the right coronary artery draining into the right pulmonary artery associated with multiple systemic-pulmonary connections.

Airway wall structure assessed by endobronchial ultrasonography and bronchial hyperresponsiveness in patients with asthma.

BACKGROUND AND OBJECTIVE: The purpose of this study was to evaluate the relationship between the wall structure assessed by using endobronchial ultrasonography (EBUS) and bronchial hyperresponsiveness in patients with asthma. METHODS: Twenty-four patients with stable asthma and 11 individuals without asthma were studied. EBUS was performed with a radial 20-MHz ultrasonic probe inserted into the intermediate bronchus undergoing flexible bronchoscopy to assess the airway wall structure. The percentage of airway wall thickness {WT%; defined as [(ideal outer diameter-ideal luminal diameter)/ideal outer diameter]×100} was determined by EBUS. We measured bronchial hyperresponsiveness to methacholine [the provocative concentration of methacholine causing a decrease of 20% or more in forced expiratory volume in 1 s (PC20)]. RESULTS: Percentage wall thickness measured by EBUS was significantly greater in patients with asthma than that in subjects without asthma (P<0.01). The evaluation of the laminar structure using EBUS indicated that the thickness of the second layer in patients with asthma was greater than that in subjects without asthma (P<0.05). PC20 was negatively correlated with the thickness of the second layer (r=0.52, P<0.01) but was not significantly correlated with other layers in patients with asthma. CONCLUSIONS: The evaluation of the bronchial mural structure using EBUS might be advantageous for assessing the relationship between airway wall remodeling and bronchial hyperresponsiveness.

Sputum eosinophilia, airway hyperresponsiveness and airway narrowing in young adults with former asthma.

BACKGROUND: 30-80% of outgrown asthma subjects develop symptoms again later in life. We investigated inflammation and function of lower airway in adolescents with former asthma. METHODS: 326 never-smoking young adults (mean age 24.0 years) were interviewed with special emphasis on history of asthma. Diagnosis of asthma was based on GINA guidelines. Former asthma subjects consisted of ones with a history of physician-diagnosed childhood asthma, who had been free of asthma symptoms without the use of medication for at least 10 years prior to the study. Provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 second (FEV(1))(PC(20)) and eosinophil percentage in induced sputum were measured. RESULTS: 31 subjects were former asthma subjects (FBA), 11 subjects were current asthma subjects (CBA) and 284 subjects had no history of asthma (non-BA). PC(20) and FEV(1)/FVC ratio were significantly lower in the FBA group than in the non-BA group (P < 0.01). Maximal mid-expiratory flow (MMF) was significantly lower in the FBA group than in the non-BA group (P < 0.05). Sputum eosinophil percentage was significantly increased in the FBA group compared with the non-BA group (P < 0.01). PC(20) was significantly lower in the CBA group than in the FBA and non-BA groups (P < 0.01). FEV(1), FEV(1)/FVC ratio and MMF were significantly lower in the CBA group than in the FBA group (P < 0.05, P < 0.05 and P < 0.05, respectively) and the non-BA group (P < 0.01, P < 0.01 and P < 0.05, respectively). Sputum eosinophils were significantly higher in the CBA group than in the FBA and non-BA groups (P < 0.01). CONCLUSIONS: This study shows that subjects with long-term outgrown asthma continue to have airway eosinophilic inflammation, airway hyperresponsiveness and airway narrowing.

Effect of pressure stress applied to the airway on cough-reflex sensitivity in Guinea pigs.

RATIONALE: We hypothesized that cough stress of the airway wall results in a self-perpetuating cough-reflex cycle in which antigen-induced increase in cough-reflex sensitivity results in pathologic cough, and the cough in turn further amplifies cough-reflex sensitivity. OBJECTIVES: To examine cough-reflex sensitivity in an experimental animal model. METHODS: We developed an experimental guinea pig model in which airway collapse similar to that in cough was induced by rapid negative pressure applied to the airway of artificially ventilated animals. We examined the influence of this stimulus on cough-reflex sensitivity to inhaled capsaicin and bronchoalveolar lavage (BAL) cell components. After the termination of artificial ventilation, the number of coughs due to capsaicin was measured, and BAL was performed. MEASUREMENTS AND MAIN RESULTS: Capsaicin cough-reflex sensitivity and the number of BAL neutrophils were increased 6 hours after stimulus application, decreasing to control levels by 24 hours. Cough-reflex sensitivity or BAL cell components were not changed in the absence of stimulus application. The number of BAL neutrophils correlated significantly with the number of coughs. Hydroxyurea inhibited the stimulus-induced increase in the number of coughs and airway neutrophil accumulation. CONCLUSIONS: Our findings suggest that cough itself is a traumatic mechanical stress to the airway wall that induces neutrophilic airway inflammation and cough-reflex hypersensitivity. Cough stress to the airway wall results in a self-perpetuating cough-reflex cycle.

Effect of montelukast in a guinea pig model of cough variant asthma.

Cough variant asthma is known as a major cause of chronic cough. Fundamental features of cough variant asthma are prolonged non-productive cough responding to bronchodilator therapy, no history of wheezing or dyspnea attack, normal cough sensitivity and slightly increased bronchial responsiveness. Recently, we reported the animal model of cough variant asthma. The aim of this study was to clarify the involvement of cysteinyl leukotrienes (cysLTs) in this model by using a specific leukotriene receptor antagonist, montelukast. Cough number and specific airway resistance (sRaw) were measured during the antigen inhalation (1.5 min) and following 18.5 min, which was carried out 72 h after the first antigen inhalation in actively sensitized guinea pigs, and then total cell number and cell differentials in bronchoalveolar lavage fluid (BALF) were measured. Montelukast significantly reduced the antigen re-inhalation-induced cough, increase in sRaw, and increase in total cell number in BALF. In conclusion, cysLTs may play an important part in antigen-induced cough associated with bronchoconstriction and airway inflammation in cough variant asthma.

Bi-weekly administration of gemcitabine plus vinorelbine in elderly patients with advanced non-small-cell lung cancer: multicenter phase II trial.

PURPOSE: Gemcitabine (GEM) and vinorelbine (VNR) have demonstrated activity as a first-line treatment in elderly patients with advanced non-small-cell lung cancer (NSCLC). We conducted a multicenter phase II trial to evaluate the efficacy and toxicity of bi-weekly administration of GEM plus VNR in elderly patients with advanced NSCLC. PATIENTS AND METHODS: Forty-six chemotherapy-naive elderly (age: >or=70 years) NSCLC patients were enrolled. Patients were eligible if they had histologically or cytologically confirmed unresectable NSCLC with measurable and/or assessable disease. Patients received GEM (1000 mg/m2) and VNR (25 mg/m2) every 2 weeks. RESULTS: The objective response rate of this treatment was 22.7% (95% confidence interval (CI), 10.3-35.1%), median survival time was 310 days, and median time to progression was 133 days. The one-year survival rate was 40.9% (95% CI, 26.3-55.4%), and most adverse events were mild. Only three (6.8%) patients needed to omit GEM because of grade 4 neutropenia or due to physician judgment. No patients suffered treatment-related death. CONCLUSIONS: Bi-weekly administration of GEM plus VNR in elderly patients was an effective, feasible and well-tolerated treatment schedule.

Prostaglandin I2 enhances cough reflex sensitivity to capsaicin in the asthmatic airway.

Inflammatory mediators are involved in the pathogenesis of airway inflammation, but the role of prostaglandin I2 (PGI2) remains obscure. This study was designed to investigate the role of PGI2 in cough reflex sensitivity of the asthmatic airway, which is characterized by chronic eosinophilic airway inflammation. The effect of beraprost, a chemically and biologically stable analogue of PGI2, on cough response to inhaled capsaicin was examined in 21 patients with stable asthma in a randomized, placebo-controlled cross over study. Capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting five or more coughs, was measured as an index of airway cough reflex sensitivity. The cough threshold was significantly (p < 0.05) decreased after two weeks of treatment with beraprost [17.8 (GSEM 1.20) microM] compared with placebo [30.3 (GSEM 1.21) microM]. PGI2 increases cough reflex sensitivity of the asthmatic airway, suggesting that inhibition of PGI2 may be a novel therapeutic option for patients with asthma, especially cough predominant asthma.

[A case of malignant mesothelioma presenting with recurrent pneumothorax].

A 71-year-old man was found to have right hydropneumothorax by chest X-ray film on a regular checkup. Thoracic drainage and bullectomy by thoracoscopy did not improve the pneumothorax, so pleurodesis with OK-432 was done. Pneumothorax recurred twice, requiring thoracic drainage and pleurodesis. Although pneumothorax was treated successfully, increased pleural effusion, pleural thickening and subcutaneal tumor at the thoracic drainage suture site developed. The concentration of hyaluronic acid in the pleural fluid was very high. The histological examination of the biopsied subcutaneous tumor showed mixed type malignant pleural mesothelioma. Chemotherapy with gemcitabine and vinorelbine could not control the progression.

A phase II study of combination chemotherapy with docetaxel and carboplatin for patients with advanced or metastatic non-small cell lung cancer.

BACKGROUND: The aim of this phase II study was to evaluate the efficacy of combination chemotherapy consisting of docetaxel and carboplatin in patients with inoperable non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: For this multicenter phase II study, the eligibility criteria included histologically or cytologically proven inoperable NSCLC, measurable lesions, Eastern Cooperative Oncology Group performance status (PS) 0-2, adequate organ and bone marrow functions, and written informed consent. Patients received 60 mg/m2 of docetaxel and carboplatin (target AUC 5.5) on day 1 every 3 weeks until disease progression. The primary end-point of this study was response rate and the secondary end-points were toxicities, time to progression and overall survival. RESULTS: A total of 40 patients were enrolled and 39 patients were eligible. A complete response and partial response were observed in 1 and 13 patients, respectively. An objective response rate was 35.9% (95% confidential interval [CI] 20.8-51.0%). The median time to progression was 5.2 months and the median overall survival was 12.0 months. The 1- and 2-year survival rates were 53.8% and 25.1%, respectively. The major toxicities were leukocytopenia and neutropenia. Grade 3 or 4 thrombocytopenia was rare and non-hematological toxicities were generally mild. Grade 3 non-hematological toxicities were observed in 6 patients (2 with nausea and vomiting, 1 with diarrhea, 1 with elevated transaminase levels, 1 with allergic reaction and 1 with edema). No grade 4 non-hematological toxicities were observed. CONCLUSION: Docetaxel and carboplatin combination chemotherapy was well tolerated and active in Japanese patients with advanced or metastatic NSCLC.

Eosinophilic inflammation, remodeling of lower airway, bronchial responsiveness and cough reflex sensitivity in non-asthmatic subjects with nasal allergy.

BACKGROUND: It has been reported that nasal allergy influences the lower airway inflammation and functions. We elucidated whether nasal allergy would contribute to lower airway inflammation and functions. METHODS: 266 subjects aged 21-39 years were interviewed with special emphasis on history of asthma and nasal allergies (perennial allergic rhinitis (PAR) and seasonal allergic rhinitis (Japanese cedar pollinosis; PO)). Symptomatic subject was defined when nasal symptoms were present during a 3-week study period. Pulmonary function, provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 s (PC20), capsaicin cough threshold defined as capsaicin concentration eliciting 5 or more coughs (C5) and eosinophil percentage in hypertonic saline-induced sputum were measured. RESULTS: Based on the interview, 232 subjects without asthma were divided into symptomatic (n = 25) and asymptomatic (n = 22) PAR, PO on-season (n = 15) and off-season (n = 36), and non-nasal allergy subjects (control) (n = 134). Sputum eosinophils were significantly greater in symptomatic PAR than another four groups (p < 0.01). FEV1/FVC ratio was significantly lower in PAR than control (p < 0.05). Maximum mean expiratory flow was lower in PAR than control (asymptomatic: p < 0.05, symptomatic: p = 0.06). C5 was not different among groups. PAR tended to have a lower PC20 compared to control (symptomatic: p = 0.078; asymptomatic: p = 0.086). CONCLUSIONS: These results suggest that eosinophilic inflammation occurred in symptomatic period of PAR may contribute to development of lower airway remodeling and bronchial hyperresponsiveness. Reversely, PO may not be associated with lower airway eosinophilic inflammation or abnormal bronchial functions. Nasal allergy dose not influence the cough reflex sensitivity.

Primary alveolar hypoventilation syndrome complicated with antiphospholipid syndrome.

A 32-year-old woman was transported to our hospital by ambulance because of loss of consciousness and breathing induced by drug intoxication. After general status was recovered, her arterial blood gas analysis under breathing room air revealed hypercapnia and hypoxemia which were caused by hypoventilation. After exclusion of apparent pulmonary, neuromuscular and central nerve diseases, she was diagnosed with primary alveolar hypoventilation syndrome. She had the complication of antiphospholipid syndrome (APS), suggesting the possibility of small lesions of the brainstem due to APS, which were too small to be detected on CT or MRI; these small lesions could cause injuries to the respiratory center.

Comparison of cough reflex sensitivity after an inhaled antigen challenge between actively and passively sensitized guinea pigs.

BACKGROUND: Late asthmatic response is observed following antigen challenge in actively, but not passively, sensitized guinea pigs. Although cough reflex sensitivity is increased after antigen challenge in actively sensitized guinea pigs, it is unknown whether the antigen-induced increase in cough reflex sensitivity develops in passively sensitized animals. The aim of this study was to compare the cough reflex sensitivity to inhaled capsaicin after an inhaled antigen challenge between actively and passively sensitized guinea pigs. METHODS: Measurement of number of coughs elicited by increasing concentrations of capsaicin (10(-6) and 10(-4) M) and bronchial responsiveness to ascending concentrations of methacholine, and analysis of bronchoalveolar lavage fluid (BALF) were separately performed 24 h after an antigen challenge in actively and passively sensitized guinea pigs. RESULTS: Percentage of eosinophils in BALF and bronchial responsiveness to methacholine were increased 24 h after the antigen challenge in both actively and passively sensitized animals compared with saline-challenged actively and passively sensitized animals, respectively. Absolute number of eosinophils in BALF from actively sensitized and antigen-challenged guinea pigs was significantly greater than that from passively sensitized and antigen-challenged animals. Cough response to capsaicin and concentration of substance P in BALF were increased 24 h after the antigen challenge in actively sensitized guinea pigs, but not in passively sensitized guinea pigs. Bronchial responsiveness, cough reflex sensitivity and substance P concentration and total cells in BALF were increased in actively sensitized and saline challenged guinea pigs compared with passively sensitized and saline challenged animals. CONCLUSION: The results suggest that active sensitization per se increases cough reflex sensitivity accompanied by increased inflammatory cells and substance P level in BALF, and antigen challenge further increases them, while simple IgE- and/or IgG-mediated allergic reaction per se or the low intensity of eosinophil infiltration in the airway itself may not affect cough reflex sensitivity in guinea pigs.

In vivo PAF-induced airway eosinophil accumulation reduces bronchial responsiveness to inhaled histamine.

Chronic eosinophilic bronchitis and bronchial hyperresponsiveness have been considered to be the fundamental features of bronchial asthma. However, the role of airway eosinophils in bronchial responsiveness in vivo has not been fully discussed. The aim of this study was to investigate the direct effect of airway eosinophil accumulation on bronchial responsiveness in vivo. Guinea pigs were transnasally treated with platelet activating factor (PAF) or vehicle twice a week for a total of 3 weeks. Anesthetized guinea pigs were surgically cannulated and artificially ventilated 48 h after the last administration of PAF or vehicle. Ten minutes after the installation of artificial ventilation, ascending doses of histamine were inhaled. In a subsequent study, selective inhibitors of diamine oxidase and histamine N-methyltransferase were intravenously administered before the histamine inhalation in the PAF-treated animals. Next study was conducted 20 min after treatment with indomethacin in this study line. Finally, ascending doses of methacholine were inhaled in our animal model. Proportion of eosinophils and the number of nuclear segmentation in bronchoalveolar lavage fluid significantly increased in guinea pigs treated with PAF compared with vehicle and this finding was confirmed histologically. Nevertheless, bronchial responsiveness to inhaled histamine, but not methacholine, was significantly decreased by the PAF treatment. This bronchoprotective effect induced by PAF remained following aminoguanidine and histamine N-methyltransferase administration, but abolished by treatment of indomethacin. These results suggest that in vivo airway eosinophils may reduce nonspecific bronchial responsiveness through production of inhibitory or bronchoprotective prostanoids, but not through histaminase production.

A guinea pig model for cough variant asthma and role of tachykinins.

Cough variant asthma is known as a major cause of chronic cough. Fundamental features of cough variant asthma are prolonged nonproductive cough responding to bronchodilator therapy, no history of wheezing or dyspnea attack, normal cough sensitivity, and slightly increased bronchial responsiveness. Animal model of cough variant asthma has not been reported. The aim of this study was to establish an animal model for studying detailed pathophysiology of cough variant asthma. Bronchial responsiveness to methacholine and cough reflex sensitivity to capsaicin were measured 72 hours after antigen (ovalbumin, OA) inhalation in actively sensitized guinea pigs. Next, cough number and specific airway resistance (sRaw) were measured during 20 minutes following reinhalation of OA solution, which was carried out 72 hours after the first OA inhalation, and then total cell number and cell differentials in bronchoalveolar lavage fluid (BALE) were measured. Bronchial responsiveness to methacholine, but not cough reflex sensitivity to capsaicin, was significantly increased 72 hours after the first inhalation of OA solution. Number of coughs, sRaw and total cell number in BALF increased significantly by the OA reinhalation, and the cough number and the increase in sRaw were significantly suppressed by beta2 agonist, procaterol. FK224, a specific neurokinin (NK) receptor antagonist, did not significantly influence the OA reinhalation-induced cough and increase in sRaw and total cell number in BALF in this model In conclusion, pathophysiologic feature of this animal model is similar to that of clinical cough variant asthma. Tachykinins may not play an important part in antigen-induced cough associated with bronchoconstriction and airway inflammation in cough variant asthma.

Th2 cytokine inhibition and cough in asthmatic and bronchitic patients.

BACKGROUND: Activated T helper lymphocytes are present in the airway and their production of cytokines is important in the pathogenesis of asthma, however, the relationship between T helper lymphocyte-derived cytokines and airway cough reflex sensitivity remains unknown. METHODS: The effect of the orally active Th2 cytokine inhibitor suplatast tosilate on cough response to inhaled capsaicin was examined in eleven patients with stable atopic asthma and compared with patients having non-atopic asthma and chronic bronchitis (the latter of which is not related to Th2 cytokines). Capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting five or more coughs, was measured as an index of airway cough reflex sensitivity. Concentration of serum total IgE level was also measured after treatment with suplatast tosilate. RESULTS: The cough threshold after two weeks treatment with suplatast tosilate was significantly greater than the value with placebo accompanied by decrease of serum IgE level in atopic asthmatics. This significance was not observed in patients with non-atopic asthma or chronic bronchitis. CONCLUSIONS: Th2 cytokines may be possible modulators augmenting airway cough reflex sensitivity in atopic asthmatic airways but not in non-atopic asthmatic or bronchitic airways.

[Influence of smoking on longitudinal decline in one-second forced expiratory volume in clinically healthy Japanese men: a longitudinal study].

We prospectively studied 2140 clinically healthy men to assess the influence of smoking on longitudinal decline in one-second forced expiratory volume (FEV1.0). All the subjects had annual medical checks including pulmonary function tests from 1995 to 1999. The mean values +/- standard deviations of annual decreases in FEV1.0 (slope) were 22 +/- 49 mL/year in non-smokers, 26 +/- 52 mL/year in former smokers, and 33 +/- 57 mL/year in current smokers (p < 0.01; non-smokers vs. current smokers). The adjusted slope (slope divided by predicted value of FEV1.0, per year) in current smokers was also greater than that in non-smokers (p < 0.01). Multiple regression analysis revealed that initial age, height, FEV1.0, and smoking status were significant parameters for determining the slope. This study clearly showed that smoking is an important risk factor foracceleration of the aging-related longitudinal decline in pulmonary function in Japanese men.