Frailty and Exacerbation of Chronic Obstructive Pulmonary Disease: Is There Any Association?

Purpose: This study investigated if individuals with chronic obstructive pulmonary disease (COPD) and frailty are more likely to have acute exacerbations of COPD or require hospitalization for exacerbation than those without frailty. Patients and Methods: Data on 135 outpatients with stable COPD were analyzed with the Cox proportional hazards model to assess the risk of future events. The Kihon Checklist was administered at baseline to classify the participants as robust, pre-frail, or frail. The follow-up period was a maximum of six and a half years. Results: In all, 76 patients (56.3%) experienced an exacerbation and 46 (34.1%) were hospitalized due to it. Multivariate Cox proportional hazards analysis that accounted for FEV1 and sex showed that the frail group was more likely to face future risks of COPD exacerbations [Hazard ratio 1.762 (95% CI 1.011-3.070), p=0.046] and hospitalizations for exacerbation [2.238 (1.073-4.667), p=0.032] than the robust group. No significant differences were observed when comparing robust patients to those who were pre-frail or pre-frail to frail either in exacerbations or hospitalizations. When comparing the C-indices for frailty and FEV1, the former index (exacerbation 0.591 and hospitalization 0.663) did not exceed the latter (0.663 and 0.769) in either analysis. Conclusion: Frail COPD patients have a more unfavorable future risk of acute exacerbations of COPD and hospitalizations for exacerbation than robust patients. However, no significant differences were observed when comparing robust patients to those who were pre-frail or pre-frail to frail, suggesting that the future risk for COPD patients with frailty is only higher compared to those who are considered robust. Additionally, FEV1 was found to be a more reliable predictor of future events than measures of frailty.

Comparison of Disease Severity Classifications of Chronic Obstructive Pulmonary Disease: GOLD vs. STAR in Clinical Practice.

BACKGROUND: In chronic obstructive pulmonary disease (COPD), there are two known classifications for assessing what is called disease severity. One is the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification, which is based on the post-bronchodilator value of FEV1 (% reference). The other is the STaging of Airflow obstruction by Ratio (STAR), with four grades of severity in subjects with an FEV1/FVC ratio <0.70: STAR 1 ≥0.60 to <0.70, STAR 2 ≥0.50 to <0.60, STAR 3 ≥0.40 to <0.50, and STAR 4 <0.40. PURPOSE: The aim of this study was to compare the staging of COPD using the GOLD and STAR classifications in clinical practice. METHODS: We reanalyzed data from our outpatient cohort study, which included 141 participants with COPD from 2015 to 2023. We compared mortality and COPD-specific health status between the GOLD 1 to 4 groups and the STAR 1 to 4 groups. RESULTS: By simple calculation, GOLD and STAR severity classes coincided in 75 participants (53.2%). The weighted Bangdiwala B value with linear weights was 0.775. The participants were observed for up to 95 months, with a median of 54 months. Death was confirmed in 29 participants (20.5%). In univariate Cox proportional hazards analyses, there was a significant difference in mortality between the GOLD 1 and GOLD 3 + 4 groups, with the GOLD 1 group used as the reference [hazard ratio 4.222 (95% CI 1.298-13.733), p = 0.017]. However, there was no statistically significant predictive relationship between STAR 1 and STAR 2, or between STAR 1 and STAR 3 + 4. St. George's Respiratory Questionnaire (SGRQ) Total and COPD Assessment Test (CAT) scores were significantly different between all GOLD groups, except for the CAT score between GOLD 1 and GOLD 2. The SGRQ Total and CAT scores were significantly different between STAR 1 and STAR 3 + 4, but not between STAR 1 and STAR 2. CONCLUSION: From the perspective of all-cause mortality and COPD-specific health status, the GOLD classification is more discriminative than STAR.

Is Frailty a Mortality Predictor in Subjects with Chronic Obstructive Pulmonary Disease?

Background: Chronic obstructive pulmonary disease (COPD) has been frequently associated with frailty. The association between frailty and mortality in patients with COPD has not yet been fully elucidated and it remains controversial whether frailty or airflow limitation is more important in predicting mortality. Methods: A total of 141 subjects with stable COPD completed pulmonary function tests and the Kihon Checklist at baseline between 2015 and 2022 and were followed for a maximum of 95 months. Using the Kihon Checklist Total score, we classified patients' frailty status as robust (0-3), pre-frail (4-7), and frail (8-25). Results: At baseline, there were 67 (47.5%) in the robust group, 36 (25.5%) pre-frail, and 38 (27.0%) frail. Death was confirmed in 29 (20.5%). Univariate Cox proportional hazards analyses revealed that all predictive relationships of frailty and airflow limitation with mortality were statistically significant, and the C-index was similar, ranging from 0.63 to 0.66. According to the Log rank test and the Cox regression model, there was a significant difference between the frail and robust groups, (p=0.004 and p=0.005, respectively). No significant differences were found in either comparison with the pre-frail group. When stratification of frailty and FEV1 as well as sex were included as explanatory variables, multivariate Cox regression analysis showed a significant difference between the robust and frail groups with respect to mortality when the robust group was used as the reference (p=0.024). The robust and pre-frail groups did not differ significantly (p=0.163). Conclusion: The mortality of frail COPD patients is higher than those classed as robust. Despite frailty being a substantial mortality predictor, it is uncertain whether or not it is a better predictor than FEV1.

The Conceptual Independence of Health Status, Respiratory Symptoms and Dyspnea in Chronic Obstructive Pulmonary Disease in Real Clinical Practice.

The hypothesis that health status is the highest ranking concept, followed by respiratory symptoms and dyspnea as the lowest ranking concepts in subjects with chronic obstructive pulmonary disease (COPD) was tested in a real clinical setting with 157 subjects with stable COPD. Spearman's rank correlation coefficients for scores of health status using the COPD Assessment Test (CAT), respiratory symptoms using the COPD Evaluating Respiratory Symptoms (E-RS) and dyspnea using Dyspnea-12 (D-12) between any two were 0.6 to 0.7. Upon categorizing the patients as "abnormal" or "normal" according to the threshold, it was found that 30 patients (19.1%) had dyspnea, respiratory symptoms and impaired health status. Dyspnea was considered an important part of respiratory symptoms, though seven patients had dyspnea but no respiratory symptoms. There were 10 patients who had respiratory symptoms without dyspnea but without health status problems. Furthermore, there were six patients who had both dyspnea and respiratory symptoms but whose health status was classified as fine. Thus, the hypothesis was correct in approximately 85% of cases.

Comparison of Predictive Properties between Tools of Patient-Reported Outcomes: Risk Prediction for Three Future Events in Subjects with COPD.

BACKGROUND: Patient-reported outcome (PRO) measures must be evaluated for their discriminatory, evaluative, and predictive properties. However, the predictive capability remains unclear. We aimed to examine the predictive properties of several PRO measures of all-cause mortality, acute exacerbation of chronic obstructive pulmonary disease (COPD), and associated hospitalization. METHODS: A total of 122 outpatients with stable COPD were prospectively recruited and completed six self-administered paper questionnaires: the COPD Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ), Baseline Dyspnea Index (BDI), Dyspnoea-12, Evaluating Respiratory Symptoms in COPD and Hyland Scale at baseline. Cox proportional hazards analyses were conducted to examine the relationships with future outcomes. RESULTS: A total of 66 patients experienced exacerbation, 41 were hospitalized, and 18 died. BDI, SGRQ Total and Activity, and CAT and Hyland Scale scores were significantly related to mortality (hazard ratio = 0.777, 1.027, 1.027, 1.077, and 0.951, respectively). The Hyland Scale score had the best predictive ability for PRO measures, but the C index did not reach the level of the most commonly used FEV1. Almost all clinical, physiological, and PRO measurements obtained at baseline were significant predictors of the first exacerbation and the first hospitalization due to it, with a few exceptions. CONCLUSIONS: Measurement of health status and the global scale of quality of life as well as some tools to assess breathlessness, were significant predictors of all-cause mortality, but their predictive capacity did not reach that of FEV1. In contrast, almost all baseline measurements were unexpectedly related to exacerbation and associated hospitalization.

Are Fatigue and Pain Overlooked in Subjects with Stable Chronic Obstructive Pulmonary Disease?

Although there have been many published reports on fatigue and pain in patients with chronic obstructive pulmonary disease (COPD), it is considered that these symptoms are seldom, if ever, asked about during consultations in Japanese clinical practice. To bridge this gap between the literature and daily clinical experience, the authors attempted to gain a better understanding of fatigue and pain in Japanese subjects with COPD. The Brief Fatigue Inventory (BFI) to analyse and quantify the degree of fatigue, the revised Short-Form McGill Pain Questionnaire 2 (SF-MPQ-2) for measuring pain and the Kihon Checklist to judge whether a participant is frail and elderly were administered to 89 subjects with stable COPD. The median BFI and SF-MPQ-2 Total scores were 1.00 [IQR: 0.11-2.78] and 0.00 [IQR: 0.00-0.27], respectively. They were all skewed toward the milder end of the respective scales. A floor effect was noted in around a quarter on the BFI and over half on the SF-MPQ-2. The BFI scores were significantly different between groups regarding frailty determined by the Kihon Checklist but not between groups classified by the severity of airflow limitation. Compared to the literature, neither fatigue nor pain are considered to be frequent, important problems in a real-world Japanese clinical setting, especially among subjects with mild to moderate COPD. In addition, our results might suggest that fatigue is more closely related to frailty than COPD.

Comparison between tools for measuring breathlessness: Cross-sectional validation of the Japanese version of the Dyspnoea-12.

INTRODUCTION: The Dyspnoea-12 (D-12) is a brief, easy to complete questionnaire for measuring breathlessness. OBJECTIVES: To facilitate further efforts to measure dyspnoea in real clinical settings, the authors aimed to develop and validate a Japanese version of the D-12 and also compare the D-12 with the Baseline Dyspnea Index (BDI) and the Activity component of the St. George's Respiratory Questionnaire (SGRQ). METHODS: The standardized procedure in accordance with international guidelines was used to create the translation. A validation study with a cross-sectional observational design was conducted on 122 subjects with stable chronic obstructive pulmonary disease (COPD). RESULTS: The internal consistency of the D-12 was high (Cronbach's coefficient α = 0.883) and similar to that of the BDI (α = 0.824) and SGRQ Activity (α = 0.872). The relationships between tools were statistically significant (|Rs | = 0.53 to 0.66). Although the scores obtained from all three tools were skewed toward the milder end of the respective scales, this deviation was most prominent in the D-12 with a floor effect of 48.4%. CONCLUSION: The Japanese version of the D-12 was successfully validated, but we should be careful of any floor effect and marked skew to the mild end of the scale, especially in subjects with mild COPD.

Is Blood Eosinophil Count a Biomarker for Chronic Obstructive Pulmonary Disease in a Real-World Clinical Setting? Predictive Property and Longitudinal Stability in Japanese Patients.

The authors examined predictive properties and the longitudinal stability of blood eosinophil count (BEC) or three strata (<100 cells/mm3, 100-299 cells/mm3 and ≥300 cells/mm3) in patients with chronic obstructive pulmonary disease (COPD) for up to six and a half years as part of a hospital-based cohort study. Of the 135 patients enrolled, 21 (15.6%) were confirmed to have died during the follow-up period. Episodes of acute exacerbation of COPD (AECOPD) were identified in 74 out of 130 available patients (56.9%), and admission due to AECOPD in 35 out of 132 (26.5%). Univariate Cox proportional hazards analyses revealed that almost all the age, forced expiratory volume in 1 s (FEV1) and health status measures using St. George's Respiratory Questionnaire (SGRQ) Total and COPD Assessment Test (CAT) Score were significantly related to these types of events, but the relationship between age and AECOPD did not reach statistical significance (p = 0.05). Neither BEC nor the three different groups stratified by BEC were significant predictors of any subsequent events. There were no significant differences in the BEC between Visits 1-3 (p = 0.127, Friedman test). The ICC value was 0.755 using log-transformed data, indicating excellent repeatability. In the case of assigning to strata, Fleiss' kappa was calculated to be 0.464, indicating moderate agreement. The predictive properties of BEC may be limited in a real-world Japanese clinical setting. Attention must be paid to the fact that the longitudinal stability of the three strata is regarded as moderate.

Development of spray-freeze-dried siRNA/PEI powder for inhalation with high aerosol performance and strong pulmonary gene silencing activity.

In the present study, a novel dry small interfering RNA (siRNA) powder for inhalation, containing polyethyleneimine (PEI) as a delivery vector, was produced by spray freeze drying (SFD). The powder had spherical and highly porous structure of approximately 10 µm in diameter with high aerosol performance for emission and lung delivery. The reconstituted siRNA/PEI complex after dissolution of the powder had almost the same physicochemical properties and in vitro gene silencing activity as the original one constituted in the sample solution before SFD, showing that the integrity of the siRNA was maintained. In in vivo studies of intratracheal administration into lung metastasis mice and healthy mice, powder with a low dose of 3 µg siRNA exhibited strong and specific gene silencing activity against tumors metastasized to the lungs, whereas it caused no significant histological changes, lactate dehydrogenase leakage, or inflammatory cytokine induction in the lungs. These results strongly indicated that inhalable dry siRNA/PEI powders can provide effective pulmonary gene silencing without severe lung injury and that SFD can be applied to the production of such powders.