Hirofumi Kiyokawa

Impact of COPD exacerbations on osteoporosis assessed by chest CT scan.

Abstract Background: COPD pathology involves not only the lungs but also extrapulmonary abnormalities. Osteoporosis is one of the most important abnormalities because it may cause vertebral compression fractures and deteriorate pulmonary function. COPD patients have many risk factors for osteoporosis, such as low BMI, decreased activity, systemic inflammation, and use of corticosteroids. Some of these factors have been shown to deteriorate with COPD exacerbations. We previously demonstrated the correlation between emphysema and osteoporosis and between emphysema progression and COPD exacerbations. Thus, the hypothesis that exacerbation causes osteoporosis progression in COPD patients was investigated. Methods: Forty-two COPD patients not on osteoporosis treatment for over 2 years were recruited. During follow-up, exacerbations had been prospectively recorded. Thoracic vertebral bone mineral density (BMD) was measured using chest CT, and the annual change in BMD was calculated. The change was compared between patients with and without a history of exacerbations. Results: The decrease in thoracic vertebral BMD was greater in patients with than in those without a history of exacerbations (median ΔBMD mg/ml⋅year: –3.78 versus –0.30, p = 0.02). Moreover, multivariate regression analysis showed that exacerbations and baseline PaO2 were independent predictors of the BMD decrease (R2 = 0.20, p = 0.007, and R2 = 0.09, p = 0.03, respectively) after adjustment for baseline age, smoking status, and airflow limitation. Conclusions: This is the first longitudinal study to demonstrate that COPD exacerbations are independently associated with osteoporosis progression. Osteoporosis progression should be evaluated in COPD patients, especially in those with a history of frequent exacerbations.

Emphysema distribution and annual changes in pulmonary function in male patients with chronic obstructive pulmonary disease

BackgroundThe progression of chronic obstructive pulmonary disease (COPD) considerably varies among patients. Those with emphysema identified by quantitative computed tomography (CT) are associated with the rapid progression assessed by forced expiratory volume in one second (FEV1). However, whether the rate of the decline in lung function is independently affected by the regional distribution or the severity of emphysema in the whole lung is unclear.MethodsWe followed up 131 male patients with COPD for a median of 3.7 years. We measured wall area percent (WA%) in right apical segmental bronchus, total lung volume, percent low attenuation volume (LAV%), and the standard deviation (SD) of LAV% values from CT images of 10 isovolumetric partitions (SD-LAV) as an index of cranial-caudal emphysema heterogeneity. Annual changes in FEV1 were then determined using a random coefficient model and relative contribution of baseline clinical parameters, pulmonary function, and CT indexes including LAV%, SD-LAV, and WA% to annual changes in FEV1 were examined.ResultsThe mean (SD) annual change in FEV1 was −44.4 (10.8) mL. Multivariate random coefficient model showed that higher baseline FEV1, higher LAV%, current smoking, and lower SD-LAV independently contributed to an excessive decline in FEV1, whereas ratio of residual volume to total lung capacity, ratio of diffusing capacity to alveolar ventilation, and WA% did not, after adjusting for age, height, weight, and ratio of CT-measured total lung volume to physiologically-measured total lung capacity.ConclusionsA more homogeneous distribution of emphysema contributed to an accelerated decline in FEV1 independently of baseline pulmonary function, whole-lung emphysema severity, and smoking status. In addition to whole-lung analysis of emphysema, CT assessment of the cranial-caudal distribution of emphysema might be useful for predicting rapid, progressive disease and for developing a targeted strategy with which to prevent disease progression.

Association of COPD exacerbation frequency with gene expression of pattern recognition receptors in inflammatory cells in induced sputum

Bacteria and viruses are major causes of chronic obstructive pulmonary disease (COPD) exacerbations. Molecular components of these pathogens are recognized by pattern‐recognition receptors (PRRs) expressed by various cells in the airway, which leads to initiation of inflammatory processes. Expression levels of PRRs in airway inflammatory cells are expected to affect susceptibility to COPD exacerbation.

Longitudinal Study of Spatially Heterogeneous Emphysema Progression in Current Smokers with Chronic Obstructive Pulmonary Disease

Background Cigarette smoke is the main risk factor for emphysema, which is a key pathology in chronic obstructive pulmonary disease (COPD). Low attenuation areas (LAA) in computed tomography (CT) images reflect emphysema, and the cumulative size distribution of LAA clusters follows a power law characterized by the exponent D. This property of LAA clusters can be explained by model simulation, where mechanical force breaks alveolar walls causing local heterogeneous lung tissue destruction. However, a longitudinal CT study has not investigated whether continuous smoking causes the spatially heterogeneous progression of emphysema. Methods We measured annual changes in ratios of LAA (LAA%), D and numbers of LAA clusters (LAN) in CT images acquired at intervals of ≥3 years from 22 current and 31 former smokers with COPD to assess emphysema progression. We constructed model simulations using CT images to morphologically interpret changes in current smokers. Results D was decreased in current and former smokers, whereas LAA% and LAN were increased only in current smokers. The annual changes in LAA%, D, and LAN were greater in current, than in former smokers (1.03 vs. 0.37%, p = 0.008; −0.045 vs. −0.01, p = 0.004; 13.9 vs. 1.1, p = 0.007, respectively). When LAA% increased in model simulations, the coalescence of neighboring LAA clusters decreased D, but the combination of changes in D and LAN in current smokers could not be explained by the homogeneous emphysema progression model despite cluster coalescence. Conversely, a model in which LAAs heterogeneously increased and LAA clusters merged somewhat in relatively advanced emphysematous regions could reflect actual changes. Conclusions Susceptibility to parenchymal destruction induced by continuous smoking is not uniform over the lung, but might be higher in local regions of relatively advanced emphysema. These could result in the spatially heterogeneous progression of emphysema in current smokers.

Computed tomography assessment of pharmacological lung volume reduction induced by bronchodilators in COPD

Abstract Pharmacological lung volume reduction in COPD is an important goal in treatment with long-acting bronchodilators because in addition to airflow limitation, lung hyperinflation considerably affects COPD symptoms. Quantitative computed tomography (CT) simultaneously provides structural information about airway dimensions, emphysematous changes, and lung volumes, some of which are difficult to be evaluated by pulmonary function. Here, we evaluated changes in CT parameters and pulmonary function in 30 patients with COPD who underwent CT scans before and one year after starting tiotropium treatment and in 12 patients with COPD who were not treated with long-acting bronchodilators. Baseline pulmonary function and CT parameters did not differ between the two groups. One-year tiotropium therapy improved physiological-indices including residual volume (RV) and ratio of RV to total lung capacity (RV/TLC) (−235 mL, p = 0.005, and −2.9%, p = 0.0001, respectively), and CT-indices including wall area percent (WA%) and inner luminal area in right upper lobe apical and lower lobe basal segmental bronchi (−1.59%, p = 0.01, 2.27 mm2, p = 0.0005; and −1.33%, p = 0.0008, 3.42 mm2, p < 0.0001, respectively), low attenuation volume (LAV) and total lung volume (CT-TLV) (−92 mL, p = 0.0003, and −211 mL, p = 0.002, respectively). Changes in LAV, CT-TLV, RV, and RV/TLC were significantly greater in the tiotropium, than the non-bronchodilator group. The tiotropium-induced reduction in LAV correlated with the decrease in RV (ρ = 0.45, p = 0.01). Our findings not only indicate the value of the comprehensive CT measurements in assessing the effects of bronchodilators, including pharmacological lung volume reduction, but also further understanding of the structural changes underlying physiological improvements induced by bronchodilators.

Thioredoxin-1 Protects against Neutrophilic Inflammation and Emphysema Progression in a Mouse Model of Chronic Obstructive Pulmonary Disease Exacerbation

Background Exacerbations of chronic obstructive pulmonary disease (COPD) are characterized by acute enhancement of airway neutrophilic inflammation under oxidative stress and can be involved in emphysema progression. However, pharmacotherapy against the neutrophilic inflammation and emphysema progression associated with exacerbation has not been established. Thioredoxin-1 has anti-oxidative and anti-inflammatory properties and it can ameliorate neutrophilic inflammation through anti-chemotactic effects and prevent cigarette smoke (CS)-induced emphysema. We aimed to determine whether thioredoxin-1 can suppress neutrophilic inflammation and emphysema progression in a mouse model of COPD exacerbation and if so, to reveal the underlying mechanisms. Results Mice were exposed to CS and then challenged with polyinosine-polycytidylic acid [poly(I:C)], an agonist for virus-induced innate immunity. Airway neutrophilic inflammation, oxidative stress and lung apoptosis were enhanced in smoke-sensitive C57Bl/6, but not in smoke-resistant NZW mice. Exposure to CS and poly(I:C) challenge accelerated emphysema progression in C57Bl/6 mice. Thioredoxin-1 suppressed neutrophilic inflammation and emphysema progression. Poly(I:C) caused early neutrophilic inflammation through keratinocyte-derived chemokine and granulocyte-macrophage colony-stimulating factor (GM-CSF) release in the lung exposed to CS. Late neutrophilic inflammation was caused by persistent GM-CSF release, which thioredoxin-1 ameliorated. Thioredoxin-1 enhanced pulmonary mRNA expression of MAP kinase phosphatase 1 (MKP-1), and the suppressive effects of thioredoxin-1 on prolonged GM-CSF release and late neutrophilic inflammation disappeared by inhibiting MKP-1. Conclusion Using a mouse model of COPD exacerbation, we demonstrated that thioredoxin-1 ameliorated neutrophilic inflammation by suppressing GM-CSF release, which prevented emphysema progression. Our findings deepen understanding of the mechanisms underlying the regulation of neutrophilic inflammation by thioredoxin-1 and indicate that thioredoxin-1 could have potential as a drug to counteract COPD exacerbation.

Relationship between periodontitis-related antibody and frequent exacerbations in chronic obstructive pulmonary disease.

Background To identify patients with chronic obstructive pulmonary disease (COPD) who are susceptible to frequent exacerbations is important. Although periodontitis aggravated by poor oral hygiene might increase the risk of lower respiratory tract infection, the relationship between periodontitis and COPD exacerbations remains unknown. This prospective cohort study investigates the relationship between periodontitis-related antibody and exacerbation frequency over a one-year period. Methods We assessed an IgG antibody titer against Porphyromonas gingivalis, which is a major pathogen of periodontitis, and then prospectively followed up 93 individuals over one year to detect exacerbations. Results The numbers of exacerbations and the rate of individuals with frequent exacerbations (at least two per year) were significantly lower in patients with higher IgG titer than those with normal IgG titer (0.8 vs. 1.2 per year, p  = 0.045 and 14.3 vs. 38.6%, p  = 0.009, respectively). Multivariate logistic regression analysis showed that being normal-IgG titer for periodontitis-related antibody significantly increased the risk of frequent exacerbations (relative risk, 5.27, 95% confidence interval, 1.30–25.7; p  = 0.019) after adjusting for other possible confounders, such as a history of exacerbations in the past year, disease severity, COPD medication and smoking status. Conclusions Normal-IgG titer for periodontitis-related antibody can be an independent predictor of frequent exacerbations. Measuring periodontitis-related antibody titers might be useful to identify patients with susceptibility to frequent exacerbations so that an aggressive prevention strategy can be designed.

Centrilobular Opacities in the Asthmatic Lung Successfully Treated with Inhaled Ciclesonide and Tiotropium: With Assessment of Alveolar Nitric Oxide Levels

BACKGROUND Despite the fact that bronchioles are involved in asthma, there have been limited asthmatic cases showing marked centrilobular opacities on computed tomography (CT) chest scans. Systemic corticosteroids have been administered in such cases, but the efficacy of extra-fine particle inhaled corticosteroids has not been assessed. CASE SUMMARY A previously healthy 64-year-old man presented with a four-month history of productive cough and progressive dyspnea despite a combination therapy with inhaled salmeterol (50 μg bid) and fluticasone (500 μg bid), sustained-release theophylline, and pranlukast because of suspicion of asthma. Physical examination revealed wheezing at the end of forced expiration. High resolution CT chest scan showed diffuse centrilobular opacities, bronchiectatic changes, and bronchial wall thickening. Transbronchial lung biopsy, bronchoalveolar lavage fluid, and transbronchial biopsy all showed predominant eosinophil infiltrates, suggesting that eosinophilic inflammation across the entire airway tree caused the abnormal CT findings. Alveolar fraction of exhaled nitric oxide level, a non-invasive marker of eosinophilic peripheral airway inflammation, was also elevated. Because he refused systemic corticosteroids, inhaled ciclesonide (400 μg bid) and inhaled tiotropium were added on to his current medication under careful observation. His symptoms, pulmonary function and CT findings promptly improved, and he had fully recovered at follow-up. DISCUSSION Extra-fine particle inhaled corticosteroids could be an alternative approach in centrilobular opacities caused by eosinophilic peripheral airway inflammation.

Interdependence of physical inactivity, loss of muscle mass and low dietary intake: Extrapulmonary manifestations in older chronic obstructive pulmonary disease patients

Extrapulmonary manifestations, such as reductions in skeletal muscle and physical inactivity, are important clinical features of patients with chronic obstructive pulmonary disease (COPD), and might depend on the severity of COPD. As it is still unclear whether the relationship between muscle loss and physical inactivity is dominated by a disease‐specific relationship or caused by patient factors, including physiological aging, we aimed to investigate the pulmonary or extrapulmonary factors associated with physical inactivity among older COPD patients.

Peri-diaphragmatic lung volume assessed by computed tomography correlates with quality of life in patients with chronic obstructive pulmonary disease

Background and objective:  Health‐related quality of life (HRQoL) is important in the management of chronic obstructive pulmonary disease (COPD). In patients with emphysema, lung hyperinflation identified radiologically as shortening and flattening of the diaphragm is associated with impaired HRQoL. It remains unclear whether shortening of the diaphragm and/or alteration in chest wall shape are associated with reduced pulmonary function and HRQoL.