One-day systemic corticosteroid administration for asthma and future "short bursts" risk in real clinical practice.

OBJECTIVE: Systemic corticosteroid administration, also called short bursts (SB), is harmful for patients with asthma; however, the actual burden of one-day SB remains unsolved. This study aimed to elucidate the characteristics of patients requiring one-day SB against asthma in clinical practice. METHODS: Consecutive patients who regularly visited our hospital for asthma treatment between January 2019 and December 2020 were reviewed and followed for one year. SB was defined as ≥3 days of systemic corticosteroid treatment for an exacerbation. One-day SB was defined as one-day of systemic corticosteroid to treat an exacerbation. The one-day SB group included patients who received only one-day SB but no SB during the preceding year. Frequent SB was defined as that occurring ≥2 times/year. RESULTS: Data on 229 patients were analyzed. Among them, 2.6% (95% confidence interval 1.2-5.6%) were in the one-day SB group. The one-day SB group was female-dominant, obese, non-eosinophilic, and non-atopic. The median one-day SB was 1.5 times/year and almost half of one-day SB were performed by patients themselves. Independent of the low pulmonary function, high blood eosinophil count, and inhaled corticosteroid dose, one-day SB was associated with future frequent SB (adjusted odds ratio = 18.2, 95% confidence interval 1.1-288, P = 0.040, compared to the no SB group). CONCLUSIONS: Although one-day SB was not frequently experienced, even one-day SB without conventional SB was associated with future frequent SB. It is important to grasp the actual condition of one-day SB and to reinforce the treatment used.

Characteristics of patients with frequent systemic corticosteroid bursts for asthma in real clinical practice: are there frequent "short bursts?"

OBJECTIVE: The data on intermittent systemic corticosteroid therapy for asthma exacerbation, clinically called a "short burst," is limited. This study aimed to investigate the characteristics of patients with frequent systemic corticosteroid bursts for asthma in real clinical practice. METHODS: Consecutive patients who regularly visited our hospital for asthma treatment between January 2019 and December 2020 were reviewed. The number of systemic corticosteroid bursts during the past 1 year was collected, and those with frequent bursts (≥2 times/year) were defined as the Frequent group. RESULTS: Data on 236 patients were analyzed. Among them, 5.5% (95% confidence interval 3.2-9.2%) were in the Frequent group. In the Frequent group, 23% of patients had no unplanned visits, and 38% experienced at least one corticosteroid burst without visiting a physician (self-medication). One-third of patients did not undertake high-dose inhaled corticosteroid treatment, and three-fourths of patients did not undertake long-acting muscarinic antagonist treatment. Low pulmonary function and increased blood eosinophils were independently associated with the Frequent group (adjusted odds ratio = 0.73, 95% confidence interval 0.55-0.99, P = 0.039, per 10% predicted increase in a forced expiratory volume in 1 s; adjusted odds ratio = 1.15, 95% confidence interval 1.02-1.29, P = 0.025, per 100/µL increase in blood eosinophils). CONCLUSIONS: There was a certain rate of frequent corticosteroid bursts in real clinical practice. It is important to determine the actual condition, as some patients experienced "hidden" frequent bursts and have the option to reinforce the treatment.

Per cent low attenuation volume and fractal dimension of low attenuation clusters on CT predict different long-term outcomes in COPD.

BACKGROUND: Fractal dimension (D) characterises the size distribution of low attenuation clusters on CT and assesses the spatial heterogeneity of emphysema that per cent low attenuation volume (%LAV) cannot detect. This study tested the hypothesis that %LAV and D have different roles in predicting decline in FEV1, exacerbation and mortality in patients with COPD. METHODS: Chest inspiratory CT scans in the baseline and longitudinal follow-up records for FEV1, exacerbation and mortality prospectively collected over 10 years in the Hokkaido COPD Cohort Study were examined (n=96). The associations between CT measures and long-term outcomes were replicated in the Kyoto University cohort (n=130). RESULTS: In the Hokkaido COPD cohort, higher %LAV, but not D, was associated with a greater decline in FEV1 and 10-year mortality, whereas lower D, but not %LAV, was associated with shorter time to first exacerbation. Multivariable analysis for the Kyoto University cohort confirmed that lower D at baseline was independently associated with shorter time to first exacerbation and that higher LAV% was independently associated with increased mortality after adjusting for age, height, weight, FEV1 and smoking status. CONCLUSION: These well-established cohorts clarify the different prognostic roles of %LAV and D, whereby lower D is associated with a higher risk of exacerbation and higher %LAV is associated with a rapid decline in lung function and long-term mortality. Combination of %LAV and fractal D may identify COPD subgroups at high risk of a poor clinical outcome more sensitively.

Long-term expansion of alveolar stem cells derived from human iPS cells in organoids.

The stable expansion of tissue-specific stem cells in vitro has contributed to research on several organs. Alveolar epithelial type II (AT2) cells function as tissue stem cells in the lung, but robust models for studying human AT2 cells are lacking. Here we report a method for the efficient generation and long-term expansion of alveolar organoids (AOs) harboring SFTPC+ alveolar stem cells derived from human induced pluripotent stem cells (hiPSCs). hiPSC-derived SFTPC+ cells self-renewed, with transcriptomes and morphology consistent with those of AT2 cells, and were able to differentiate into alveolar epithelial type I (AT1)-like cells. Single-cell RNA-seq of SFTPC+ cells and their progenitors demonstrated that their differentiation process and cellular heterogeneity resembled those of developing AT2 cells in vivo. AOs were applicable to drug toxicology studies recapitulating AT2-cell-specific phenotypes. Our methods can help scientists overcome the limitations of current approaches to the modeling of human alveoli and should be useful for disease modeling and regenerative medicine.

Serum matrix metalloproteinase levels in polymyositis/dermatomyositis patients with interstitial lung disease.

OBJECTIVE: We aimed to clarify the clinical significance of serum levels of MMPs in interstitial lung disease (ILD) complicated with PM/DM (PM/DM-ILD). METHODS: We retrospectively analysed serum levels of seven subsets of MMPs in 52 PM/DM-ILD patients diagnosed at Kyoto University Hospital or Tenri Hospital from January 2005 to December 2014. The patients were sub-grouped based on the presence of anti-amimoacyl-tRNA synthetase antibody (anti-ARS antibody), anti-melanoma differentiation-associated protein 5 antibody (anti-MDA5 antibody) or lack of the antibodies (ARS-ILD, MDA5-ILD and other-ILD groups, respectively) and independently analysed. Eighteen PM/DM patients without ILD and 55 healthy control were also analysed. Associations between serum levels of MMPs and clinical findings including mortality were analysed. RESULTS: Among the MMPs analysed, MMP-7 serum levels in the ARS-ILD group were significantly higher compared with those in any of the other groups of PM/DM patients or in healthy controls. On the other hand, in the MDA5-ILD group, serum MMP-7 levels >5.08 ng/ml were associated with worse overall survival both in univariate (P = 0.017; odds ratio 18.0; 95% CI 1.69, 192.00) and multivariate (P = 0.027; odds ratio 14.60; 95% CI 1.11, 192.00) analyses. Immunohistochemical analysis suggested that MMP-7 was expressed in type II alveolar epithelial cells adjacent to the fibrotic lesions. CONCLUSION: Serum MMP-7 levels were higher in anti-ARS antibody-positive PM/DM-ILD patients, while higher serum MMP-7 levels among anti-MDA5 antibody-positive PM/DM-ILD patients were associated with a worse prognosis. Fibrotic processes may be associated with the elevation of serum MMP-7 levels.

The prevalence and disease burden of severe eosinophilic asthma in Japan.

Background: There are limited data on the prevalence and burden of severe eosinophilic asthma (SEA) both in Japan and globally. This study aimed to assess the prevalence and burden of SEA in Japan. Methods: This study was a retrospective, observational cohort analysis using health records or health insurance claims from patients with severe asthma treated at Kyoto University Hospital. The primary outcome was the prevalence of SEA, defined as a baseline blood eosinophil count ≥300 cells/µL. Secondary outcomes included frequency and risk factors of asthma exacerbations, and asthma-related healthcare resource utilization and costs. Results: Overall, 217 patients with severe asthma were included; 160 (74%) had eosinophil assessments. Of these, 97cases (61%), 54cases (34%), and 33cases (21%) had a blood eosinophil count ≥150, ≥300, and ≥500 cells/µL, respectively. Proportion of SEA was 34%. Blood eosinophil count was not associated with a significantly increased frequency of exacerbations. In the eosinophilic group, lower % forced expiratory volume in 1 second and higher fractional exhaled nitric oxide were predictive risk factors, while the existence of exacerbation history was a predictive risk factor for asthma exacerbations in the non-eosinophilic group. Severe asthma management cost was estimated as ¥357,958/patient-year, and asthma exacerbations as ¥26,124/patient-year. Conclusions: Approximately, one-third of patients with severe asthma in Japan have SEA. While risk factors for exacerbations differed between SEA and severe non-eosinophilic asthma, both subgroups were associated with substantial disease and economic burden. From subgroup analysis, blood eosinophil counts could be an important consideration in severe asthma management.

Perspectives on End-of-Life Treatment among Patients with COPD: A Multicenter, Cross-sectional Study in Japan.

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality. Since patients with severe COPD may experience exacerbations and eventually face mortality, advanced care planning (ACP) has been increasingly emphasized in the recent COPD guidelines. We conducted a multicenter, cross-sectional study to survey the current perspectives of Japanese COPD patients toward ACP. "High-risk" COPD patients and their attending physicians were consecutively recruited. The patients' family configurations, understanding of COPD pathophysiology, current end-of-life care communication with physicians and family members, and preferences for invasive life-sustaining treatments including mechanical ventilation (MV) and cardiopulmonary resuscitation (CPR) were evaluated using a custom-made, structured, self-administered questionnaire. Attending physicians were also interviewed, and we evaluated the patient-physician agreement. Among the 224 eligible "high-risk" patients, 162 participated. Half of the physicians (54.4%) thought they had communicated detailed information; however, only 19.4% of the COPD patients thought the physicians did so (κ score = 0.16). Less than 10% of patients wanted to receive invasive treatment (MV, 6.3% and CPR, 9.4%); interestingly, more than half marked their decision as "refer to the physician" (MV 42.5% and CPR 44.4%) or "refer to family" (MV, 13.8% and CPR, 14.4%). Patients with less knowledge of COPD were less likely to indicate that they had already made a decision. Although ACP is necessary to cope with severe COPD, Japanese "high-risk" COPD patients were unable to make a decision on their preferences for invasive treatments. Lack of disease knowledge and communication gaps between patients and physicians should be addressed as part of these patients' care.

The Clinical Significance of Body Weight Loss in Idiopathic Pulmonary Fibrosis Patients.

BACKGROUND: The significance of the nutritional status in idiopathic pulmonary fibrosis (IPF) is largely unknown. Temporal body weight (BW) change, a dynamic index of nutrition status, can detect the malnutrition more accurately than the conventional single-point body mass index evaluation. OBJECTIVE: To investigate how the temporal BW change influences the clinical courses of IPF. METHODS: This multicenter study enrolled IPF patients from four referral hospitals of interstitial lung diseases in Japan (the Japanese cohort, the derivation cohort) and the Royal Brompton Hospital (the UK cohort, the validation cohort). The annual rate of BW change from the initial presentation was evaluated. A > 5% decrease of BW was defined as a significant BW loss. RESULTS: Twenty-seven out of 124 patients in the Japanese cohort and 13 out of 86 patients in the UK cohort showed significant BW loss. Patients with BW loss showed significantly worse survival in both cohorts. Multivariate analyses revealed that BW loss was an independent factor for decreased survival (Japanese cohort: p = 0.047, UK cohort: p = 0.013). A 6.1% loss of BW was chosen as the optimal cutoff value to predict the 2-year mortality from the initial presentation. The stratified analysis revealed that a 6.1% or greater BW loss could predict worse survival specifically in cases without a greater than 10% decline in forced vital capacity (FVC). CONCLUSIONS: BW loss is independently associated with the survival of IPF patients, particularly when a decline in the FVC was not observed. Further studies are needed to understand the mechanisms underlying BW loss in IPF.

Effects of acupuncture on nutritional state of patients with stable chronic obstructive pulmonary disease (COPD): re-analysis of COPD acupuncture trial, a randomized controlled trial.

BACKGROUND: There are an increasing number of evidences that chronic obstructive pulmonary disease (COPD) is a systemic illness and that bodyweight loss is its prominent manifestation. We focused on the nutritional outcomes to find out the effectiveness of acupuncture on nutritional state of COPD patients and on their prognosis in our previous interventional study. METHODS: The present study is re-analysis of our previous interventional study, COPD Acupuncture Trial (CAT) published in 2012. Data from CAT was re-analyzed in terms of nutritional status, inflammatory biomarkers, and prognostic index. Nutritional states were evaluated by the measurements of body weight, body composition, and muscle strength, and the nutritional hematological examination results (retinol-binding protein (RBP), prealbumin (PA), transferrin (Tf), and hemoglobin (Hb) in serum), and inflammation biomarkers such as carboxyhemoglobin (COHb), High sensitivity C-reactive protein (Hs-CRP), Tumor Necrosis Factor-alpha (TNF-α), Interleukin 6 (IL-6), and Serum Amyloid A (SAA) were measured. The BODE index was measured in terms of prognosis. These measurements were compared between the real acupuncture group (RAG) and the placebo acupuncture group (PAG). All data are presented as mean (SD) or mean (95% CI). The difference between baseline and final volumes was compared using analysis of covariance (ANCOVA). Moreover, correlations between nutritional hematological examination scores and inflammation biomarker parameters were assessed using Spearman's rank correlation coefficient. RESULTS: After 12 weeks, the change in body weight was significantly greater in the RAG compared with the PAG (mean [SD] difference from baseline: 2.5 [0.4] in RAG vs - 0.5 [1.4] in PAG; mean difference between the groups: 3.00, 95% CI, 2.00 to 4.00 with ANCOVA). Patients in RAG also had improvements in the results of nutritional hematological examination (RBP, PA, Tf, Hb), Inflammation biomarkers (TNF-α, IL-6, SAA, Hs-CRP, COHb) and the BODE index. CONCLUSION: This study demonstrated some clear evidences that acupuncture can be a useful adjunctive therapy to improve nutritional state of COPD patients. TRIAL REGISTRATION: UMIN Clinical Trials Registry ( UMIN000001277 ). Retrospectively registered.

Serum soluble interleukin-2 receptor as a biomarker in immunoglobulin G4-related disease.

OBJECTIVES: Serum soluble interleukin-2 (IL-2) receptor (sIL-2R) might reflect disease activity in immunoglobulin G4-related disease (IgG4-RD). We aimed to elucidate the clinical significance of blood markers, including sIL-2R, in patients with IgG4-RD. METHODS: We enrolled 59 patients with IgG4-RD and investigated the association between blood markers (white blood cells, C-reactive protein, sIL-2R, IgG, IgG4, IgE, total hemolytic complement), and clinical indices. RESULTS: At baseline, serum sIL-2R (Rs = 0.532, p < .001) and IgG4 (Rs = 0.545, p < .001) levels showed significant correlation to the number of organs involved. During follow-up period (median, 70 months; range, 7-195 months), 40 patients were treated with corticosteroids. Receiver operating characteristic (ROC) analysis showed that baseline sIL-2R levels most accurately predicted patients requiring glucocorticoid treatment (area under the ROC curve, 0.807). Among the 46 patients who improved, sIL-2R and IgG4 levels decreased in 42 and 41 patients, respectively. Among them, serum sIL-2R levels decreased to a normal range in 42 patients (91%), whereas IgG4 levels normalized in 19 (41%). CONCLUSION: The serum sIL-2R level is a potential biomarker for IgG4-RD that may reflect the number of involved organs and may predict patients requiring glucocorticoid treatment.

Staphylococcus aureus enterotoxin sensitization involvement and its association with the CysLTR1 variant in different asthma phenotypes.

BACKGROUND: Sensitization to Staphylococcus aureus enterotoxin (SE) is a known risk factor for asthma susceptibility and severity. However, how SE sensitization is involved in asthma, particularly nonatopic asthma and/or late-onset asthma, remains uncertain. OBJECTIVE: To clarify the involvement of SE sensitization in nonatopic and/or late-onset asthma and its association with a polymorphism of the cysteinyl leukotriene receptor 1 gene (CysLTR1), which was examined because CysLT signaling is closely associated with late-onset eosinophilic asthma. METHODS: We assessed associations between sensitization to SE (A and/or B) and clinical indexes in 224 patients with asthma (mean age, 62.3 years; 171 women) from a cohort of the Kinki Hokuriku Airway Disease Conference, particularly those with nonatopic asthma (not sensitized to common aeroallergens) and/or late-onset asthma. Associations between SE sensitization and CysLTR1 polymorphism (rs2806489), a potential regulatory variant for atopic predisposition in women, were also assessed in a sex-stratified manner. RESULTS: A total of 105 patients (47%) with asthma were sensitized to SE. Among patients with nonatopic asthma (n = 67) or with late-onset asthma (n = 124), those sensitized to SE had significantly higher serum total IgE and periostin levels than those not sensitized. In nonatopic patients, a rapid decrease in forced expiratory volume in 1 second was associated with SE sensitization. In women with asthma, rs2806489 was associated with sensitization to SEB and age at asthma onset. CONCLUSION: SE sensitization contributes to TH2 inflammation in nonatopic and/or late-onset asthma. In women with asthma, the CysLTR1 variant might be associated with sensitization to SEB and age at asthma onset.

Role of mitochondrial hydrogen peroxide induced by intermittent hypoxia in airway epithelial wound repair in vitro.

The airway epithelium acts as a frontline barrier against various environmental insults and its repair process after airway injury is critical for the lung homeostasis restoration. Recently, the role of intracellular reactive oxygen species (ROS) as transcription-independent damage signaling has been highlighted in the wound repair process. Both conditions of continuous hypoxia and intermittent hypoxia (IH) induce ROS. Although IH is important in clinical settings, the roles of IH-induced ROS in the airway repair process have not been investigated. In this study, we firstly showed that IH induced mitochondrial hydrogen peroxide (H2O2) production and significantly decreased bronchial epithelial cell migration, prevented by catalase treatment in a wound scratch assay. RhoA activity was higher during repair process in the IH condition compared to in the normoxic condition, resulting in the cellular morphological changes shown by immunofluorescence staining: round cells, reduced central stress fiber numbers, pronounced cortical actin filament distributions, and punctate focal adhesions. These phenotypes were replicated by exogenous H2O2 treatment under the normoxic condition. Our findings confirmed the transcription-independent role of IH-induced intracellular ROS in the bronchial epithelial cell repair process and might have significant implications for impaired bronchial epithelial cell regeneration.

Risk factors for stomatitis in patients with lymphangioleiomyomatosis during treatment with sirolimus: A multicenter investigator-initiated prospective study.

PURPOSE: Lymphangioleiomyomatosis is a rare lung disease caused by proliferation of abnormal smooth muscle-like cells and typically occurs in premenopausal women. Sirolimus is now the first-line drug for the treatment of lymphangioleiomyomatosis. Sirolimus-induced stomatitis is the most frequent adverse event experienced during treatment. To identify risk factors, we investigated the association of stomatitis incidence with patient background data and treatment parameters, using data from the multicenter long-term sirolimus trial. METHODS: Subjects received sirolimus for 2 years at doses adjusted to maintain a trough blood level of 5 to 15 ng/mL. The incidence of stomatitis was correlated with baseline demographics, clinical characteristics, and changes in the longitudinal data. Risk factors at baseline were assessed by using univariate and multivariate analyses. RESULTS: The most frequent adverse event was stomatitis, with the cumulative rate reaching 88.9% by 9 months, higher than that reported in postrenal transplant patients. The repetition, the duration, and the severity of stomatitis events were variable among patients. We found that patients with low hemoglobin (Hb) (<14.5 g/dL) showed significantly higher incidence than those with high Hb (≥14.5 g/dL, P < .01). The cumulative rate for stomatitis incidence was significantly associated with a decrease in the mean corpuscular volume, while the Hb level was constant; thus, red blood cell count in patients increased during the study. CONCLUSIONS: Baseline Hb levels and a decrease in mean corpuscular volume during treatment were correlated with the incidence of stomatitis.

Disease severity staging system for idiopathic pulmonary fibrosis in Japan.

BACKGROUND AND OBJECTIVE: In Japan, the classification of disease severity of idiopathic pulmonary fibrosis (IPF) (J-system) has been used in making decisions on medical care subsidies. The present J-system consists of arterial partial pressure of oxygen (PaO2 ) and exercise desaturation in stages of I-IV. It provides a good prognostic classification in stages III and IV, but not in stages I and II. Therefore, we propose a revised system to improve discriminative ability in stages I and II. METHODS: We compared the revised J-system with the present J-system using Cox proportional hazards model to predict mortality rate. We also evaluated the recently proposed GAP (Gender, Age and Physiology) system in comparison to both J-systems. RESULTS: Two-hundred and fifteen IPF patients were studied retrospectively. A univariate model showed that the present and revised J-systems and a modified GAP system were all significant prognostic factors. The C-statistic for discriminating prognosis was higher in the revised J-system than the modified GAP system and the present J-system (0.677, 0.652 and 0.659, respectively). The C-statistics of these models produced from the 10 000 bootstrap samples were similar to those of the original models, suggesting good internal validation (0.665 (95% CI: 0.621-0.705), 0.645 (0.600-0.686) and 0.659 (0.616-0.700), respectively). Multivariate analysis revealed that the revised J-system (P = 0.0038) and the modified GAP system (P = 0.0029) were independent prognostic factors. CONCLUSION: The revised J-system can provide a better mortality prediction than the present one. Both the revised J-system and the modified GAP system are independent and valuable tools for prognostication and clinical management for IPF.

A 12-week, randomized, parallel-group, proof-of-concept study of tulobuterol patch and salmeterol inhaler as add-on therapy in adult-onset mild-to-moderate asthma.

Patch formulation of tulobuterol has been used in asthma treatment as a long-acting ß2 -agonist (LABA) through sustained skin absorption. Its treatment efficacy, especially in small airways, remains poorly understood. The study aim was to investigate LABA add-on effects of tulobuterol patch (TP) and salmeterol inhaler (SA) on pulmonary function, asthma control and health status. Patients who had adult-onset under-control asthma, despite taking inhaled corticosteroids, were enrolled in a randomized, open-label, parallel-group, proof-of-concept study of 12-week add-on treatment with TP (n=16) or SA (n=17). Spirometry, impulse oscillometry (IOS), exhaled nitric oxide levels, and clinical questionnaires of asthma control, health status (St. George's Respiratory Questionnaire: SGRQ), and symptoms were evaluated every 4 weeks. Add-on treatment of SA significantly improved the spirometric indices of small airway obstruction (forced expiratory flow between 25% and 75% of FVC: FEF25-75 , and maximum expiratory flow at 25% of FVC: MEF25 ) and IOS indices of whole respiratory resistance (resistance at 5 Hz) as compared to TP. In intra-group comparisons, add-on treatment of TP improved the scores of the asthma control test and the total SGRQ, as well as the symptom and impact components of the SGRQ. SA add-on treatment improved FEV1 and IOS parameters of resistance at 20 Hz and reactance at 5 Hz. Neither of the treatments improved exhaled nitric oxide levels. In conclusion, add-on treatment of TP improved asthma control and health status, whereas SA improved pulmonary function measures associated with large and small airway involvement among patients with adult-onset mild-to-moderate asthma.

Chronic Kidney Disease Predicts Survival in Patients with Idiopathic Pulmonary Fibrosis.

BACKGROUND: The prevalence of chronic kidney disease (CKD) increases with age as with idiopathic pulmonary fibrosis (IPF). OBJECTIVES: We assessed the prevalence of CKD (stages 3-5) and investigated the relationship of CKD to clinical features and outcomes in patients with IPF. METHODS: This study comprised 123 patients with IPF; 61 subjects with chronic obstructive pulmonary disease (COPD), which was reportedly associated with CKD, were also enrolled as a disease control. CKD (stages 3-5) was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. RESULTS: Thirty-seven patients (30%) with IPF and 14 controls (23%) with COPD were diagnosed with CKD, and these frequencies were not significantly different. The patients with IPF and CKD were older (p < 0.01) and had a higher frequency of hypertension (p = 0.048) and ischemic heart disease (p = 0.02) than those with IPF but without CKD. Furthermore, the diffusing capacity of the lung for carbon monoxide (DLCO) and the 6-min walking distance in the patients with CKD were significantly lower (40.0 ± 13.2 vs. 45.9 ± 14.4%, p = 0.04, and 416 ± 129 vs. 474 ± 84 m, p = 0.01, respectively) than in the patients without CKD. The outcome of the patients with CKD showed significantly worse survival compared with the patients without CKD (p = 0.04). Moreover, eGFR remained an independent predictor of survival after adjusting for age and pulmonary function data. CONCLUSION: A substantial percentage of IPF patients have CKD. CKD with a low eGFR was associated with decreased survival in IPF.

Changes in Energy Metabolism after Continuous Positive Airway Pressure for Obstructive Sleep Apnea.

RATIONALE: Disrupted energy homeostasis in obstructive sleep apnea (OSA) may lead to weight gain. Paradoxically, treating OSA with continuous positive airway pressure (CPAP) may also promote weight gain, although the underlying mechanism remains unclear. OBJECTIVES: To explore the underlying mechanism by which patients with OSA gain weight after CPAP. METHODS: A comprehensive assessment of energy metabolism was performed in 63 newly diagnosed OSA study participants (51 men; 60.8 ± 10.1 yr; apnea-hypopnea index >20 h(-1)) at baseline, CPAP initiation, and at a 3-month follow-up. Measurements included polysomnography, body weight, body composition, basal metabolic rate (BMR), hormones (norepinephrine, cortisol, leptin, ghrelin, insulin-like growth factor-1), dietary intake, eating behavior, and physical activity. MEASUREMENTS AND MAIN RESULTS: BMR significantly decreased after CPAP (1,584 kcal/d at baseline, 1,561 kcal/d at CPAP initiation, and 1,508 kcal/d at follow-up; P < 0.001), whereas physical activity and total caloric intake did not significantly change. In multivariate regression, baseline apnea-hypopnea index, Δurine norepinephrine, and CPAP adherence were significant predictors of ΔBMR. The weight gainers had higher leptin levels, lower ghrelin levels, and higher eating behavior scores than the non-weight gainers, indicating a positive energy balance and disordered eating behavior among the weight gainers. Among the parameters related to energy metabolism, increased caloric intake was a particularly significant predictor of weight gain. CONCLUSIONS: Although a reduction in BMR after CPAP predisposes to a positive energy balance, dietary intake and eating behavior had greater impacts on weight change. These findings highlight the importance of lifestyle modifications combined with CPAP. Clinical trial registered with http://www.umin.ac.jp/english/ (UMIN000012639).

Imbalance of endogenous prostanoids in moderate-to-severe asthma.

BACKGROUND: Inhalation studies suggested "protective" roles of exogenous prostaglandin E2, but the clinical relevance of endogenous prostanoids in asthma is poorly known. The objective of this study is to measure sputum levels of prostanoids in asthmatic patients to correlate with clinical indices. METHODS: Mild (n = 41) or moderate-to-severe (19) asthmatics and 27 normal controls were examined for pulmonary function (FEV1 and mid-forced expiratory flow), sputum cell differentials, and sputum levels of prostaglandins D2, E2, F2α, and thromboxane B2 measured by sandwich enzyme immunoassay. RESULTS: Each prostanoid level did not differ among the three groups. Sputum number of bronchial epithelial cells was greater in moderate-to-severe asthmatics than in the other two groups, suggesting epithelial desquamation. Levels of prostaglandin F2α, D2, and thromboxane B2 positively correlated with the severity of airflow obstruction in the 60 asthmatic patients, whereas prostaglandin E2 levels were unrelated to pulmonary function. The ratio of combined "contractile" prostanoids (prostaglandin D2/prostaglandin F2α/thromboxane B2) to prostaglandin E2 was 2.5-fold greater in moderate-to-severe asthmatics than in controls (p = 0.001) or in mild asthmatics (p = 0.0002) but did not differ between the latter two groups. In the two asthmatic groups combined, this ratio positively correlated with the sputum number of epithelial cells. The combined "contractile" prostanoids levels positively correlated with prostaglandin E2 levels in controls and in mild asthmatics but not in moderate-to-severe asthmatics. CONCLUSIONS: An imbalance in production, breakdown, or both between prostaglandin E2 and other prostanoids possibly due to epithelial damage may be involved in the pathogenesis of moderate-to-severe asthma.

Interstitial fluid flow of alveolar primary septa after pneumonectomy.

Neoalveolation is known to occur in the remaining lung after pneumonectomy. While compensatory lung growth is a complex process, stretching of the lung tissue appears to be crucial for tissue remodeling. Even a minute shear stress exerted on fibroblasts in the interstitial space is known to trigger cell differentiation into myofibroblast that are essential to building new tissues. We hypothesize that the non-uniform motion of the primary septa due to their heterogeneous mechanical properties under tidal breathing induces a spatially unique interstitial flow and shear stress distribution in the interstitial space. This may in turn trigger pulmonary fibroblast differentiation and neoalveolation. In this study, we developed a theoretical basis for how cyclic motion of the primary septal walls with heterogeneous mechanical properties affects the interstitial flow and shear stress distribution. The velocity field of the interstitial flow was expressed by a Fourier (complex) series and its leading term was considered to induce the basic structure of stress distribution as long as the dominant length scale of heterogeneity is the size of collapsed alveoli. We conclude that the alteration of mechanical properties of the primary septa caused by pneumonectomy can develop a new interstitial flow field, which alters the shear stress distribution. This may trigger the differentiation of resident fibroblasts, which may in turn induce spatially unique neoalveolation in the remaining lung. Our example illustrates that the initial forming of new alveoli about half the size of the original ones.

Serial perfusion in native lungs in patients with idiopathic pulmonary fibrosis and other interstitial lung diseases after single lung transplantation.

BACKGROUND: Lung perfusions after single lung transplantation (SLT) have not been fully clarified in patients with interstitial lung disease (ILD). The present study aimed to investigate temporal changes in native lung perfusion and their associated clinical factors in patients with ILD who have undergone SLT. METHODS: Eleven patients were enrolled. Perfusion scintigraphy was serially performed up to 12 months after SLT. Correlations between the post-operative perfusion ratio in the native lung and clinical parameters, including pre-operative perfusion ratio and computed tomography (CT) volumetric parameters, were evaluated. RESULTS: On average, the perfusion ratio of the native lung was maintained at approximately 30% until 12 months after SLT. However, the ratio declined more significantly in idiopathic pulmonary fibrosis (IPF) than in other ILDs (p = 0.014). The perfusion ratio before SLT was significantly correlated with that at three months after SLT (ρ = 0.64, p = 0.048). The temporal change of the perfusion ratio in the native lung did not correlate with those of the CT parameters. CONCLUSION: The pre-operative perfusion ratio may predict the post-operative perfusion ratio of the native lung shortly after SLT in ILD. Perfusion of the native lung may decline faster in IPF compared with other ILDs.