Economic Considerations of Lung Volume Reduction Surgery and Bronchoscopic Valves.

Chronic obstructive pulmonary disease is a challenging disease to treat, and at advanced stages of the disease, procedural interventions become some of the only effective methods for improving quality of life. However, these procedures are often very costly. This article reviews the medical literature on cost-effectiveness of lung volume reduction surgery and bronchoscopic valve placement for lung volume reduction. It discusses the anticipated costs and economic impact in the future as technique is perfected and outcomes are improved.

Do We Need to Assess Quality-of-Life with Both the St George's Respiratory Questionnaire and the EuroQol 5-Dimension Questionnaire in a Clinical Study with an Economic Component: Insights from the REVOLENS Study in Severe Emphysema.

Introduction: The use of two quality-of-life questionnaires in a single clinical trial with an economic component can be challenging due to the associated workload in terms of data collection and an increased risk of missing data. The aim of our study was to determine whether the questionnaire chosen to measure health status, the St. George's Respiratory Questionnaire (SGRQ), could be administered on its own without adding the EuroQol five dimensions questionnaire (EQ-5D) for economic evaluation in emphysema studies. Materials and Methods: Data were prospectively collected during the REVOLENS trial assessing endobronchial coil treatment in severe emphysema. To quantify the association between the two questionnaires, correlations between the EQ-5D and the SGRQ were first tested and the concordance was then studied in order to know whether the two questionnaires were interchangeable. Finally, the Starkie et al algorithm predicting EQ-5D utility values from the SGRQ was used on REVOLENS's individual patient data. The Student's t-test, correlation and concordance between EQ-5D individual value (from the REVOLENS study) and predicted value (from the Starkie et al algorithm) were studied to test this algorithm. Results: Results showed a strong correlation but no concordance between the EQ-5D and the SGRQ, demonstrating that the two questionnaires are not interchangeable. Moreover, the algorithm predicting EQ-5D utilities from the SGRQ did not provide utility values comparable to those observed in the REVOLENS study. Indeed, our study demonstrated a strong correlation between predicted and individual EQ-5D values but no concordance. Conclusion: The use of both the EQ-5D and the SGRQ in a clinical study with an economic component is justified. Based on our results, the SGRQ should not be used to obtain a utility score to calculate the incremental cost-effectiveness ratio and conclude on the efficiency of an intervention in emphysema patients.

A retrospective evaluation of the pulmonary function tests and quality of life assessment surveys of emphysema patients subject to coil treatment.

INTRODUCTION: Bronchoscopic volume reduction treatments are among the important alternatives for selected emphysema patients with a dyspneic course despite optimal medical treatment. Our aim was to carry out a retrospective scan of the data for COPD patients subject to coil treatment at our center for assessing whether coil procedure has an impact on the respiratory symptom and pulmonary function tests in COPD patients. MATERIALS AND METHODS: The data of 41 patients with severe emphysema and treated with coils between 2017-2020 were evaluated retrospectively. Cardiopulmonary rehabilitation programs were completed for all patients prior to the procedure and they were assessed with pulmonary function test (PFT), diffusing capacity for carbonmonoxide test (DLCO), body plethysmography, 6-minute walk test, ventilation/perfusion scintigraphy, St. George's Respiratory Questionnaire (SGRQ). Data acquired prior to the procedure and 3rd month control data after the procedure were recorded and SGRQ was applied via face-to-face interviews during the controls by doctors working on Pulmonary Diseases as was the case before the procedure. RESULT: SGRQ questionnaires of 32 patients were evaluated. Statistically significant changes were observed after the procedure in symptom, activity, impact score and total score which were calculated prior to the procedure. Pre and post procedure FEV1, FVC, FEV1/FVC, PEF, FEF25/75 parameters were used for the comparison made via SFT. Statistically significant changes were observed in FEV1, FVC, FEF25/75 when the pre and post-procedure SFT parameters of the 32 patients included in the study were compared. CONCLUSIONS: A statistically significant improvement was observed in the PFT parameters and quality of life questionnaires following the coil procedure which is a bronchoscopic volume reduction procedure.

Clinical Features Of Women With COPD: Sex Differences In A Cross-Sectional Study In Spain ("The ESPIRAL-ES Study").

Aim: This cross-sectional multicenter study was performed aimed at describing the clinical characteristics of women with COPD attended in routine daily practice in Spain. Methods and results: Of a total of 1610 consecutive patients diagnosed with COPD recruited in primary care centers and pneumology services throughout Spain over a 90-day period, 17.9% (n=286) were women, with a median age of 62 years. Differences in COPD phenotypes by sex were statistically significant (P = 0.002). Males as compared with females showed a higher prevalence of non-exacerbator (47.9% vs 42.2%) and exacerbator with chronic bronchitis (22.9% vs 18.8%) phenotypes, whereas the ACOS phenotype was more common among females (21.7% vs 12.9%). The mean (SD) CAT score was similar in men than in women (20.8 [9.0] vs 21.2 [8.7], P = 0.481), as well as the impact of the disease on the quality of life according to CAT scores of <5 (no impact), 5-9 (low), 10-20 (medium), >20 (high), and >30 (very high). Sex-related differences according to smoking status were statistically significant (P < 0.001), with a higher percentage of men as compared with women in the groups of current smokers and ex-smokers; never-smokers were higher in women (9.1%) than in men (0.6%). The mean number of comorbidities was 2.01 (1.43) (95% CI 1.93-2.09) in males and 1.99 (1.42) (95% CI 1.83-2.16) (P = 0.930) in females, but cardiovascular diseases (hypertension, ischemic heart disease, chronic heart failure) were more frequent in men, whereas metabolic disorders (osteoporosis) were more frequent in women. Conclusion: This study highlights the impact of COPD in women and the importance of continuing sex-based research in tobacco-related respiratory diseases.

Quantitative assessment of pulmonary vascular alterations in chronic obstructive lung disease: Associations with pulmonary function test and survival in the KOLD cohort.

PURPOSE: Despite the high prevalence of pulmonary vascular alterations and their substantial impact on chronic obstructive pulmonary disease (COPD), tools for the direct in vivo assessment of pulmonary vascular alterations remain limited. Thus, the purpose of this study was to automatically extract pulmonary vessels from volumetric chest CT and evaluate the associations between the derived quantitative pulmonary vessel features and clinical parameters, including survival, in COPD patients. METHODS: This study included 344 adult COPD patients. Pulmonary vessels were automatically extracted from volumetric chest CT data. Quantitative pulmonary vessel features were obtained from various lung surface areas (LSAs), which are theoretical surface areas drawn at different depths from the pleural borders. The total number of vessels (Ntotal) and number of vessels with vessel area (VA) less than 5 mm2 (N<5mm) were counted as both robust values and as values per 10 cm2 of LSA (Ntotal/LSA; N<5mm/LSA). The average VA (VAmean) and percentage of measured VA in the corresponding LSA (%VA) were measured. Associations between quantitative pulmonary vessel features and clinical parameters, including survival and the pulmonary function test (PFT), were evaluated. RESULTS: The pulmonary vessels were automatically extracted with 100% technical success. Cox regression analysis showed Ntotal/LSA, N<5mm/LSA, VAmean, and %VA to be significant predictors of survival (hazard ratio (HR), 0.80, 0.75, 0.70, 0.49, respectively). Patients classified into high-risk groups by %VA18mm (cut-off = 3.258), chosen because it demonstrated the strongest statistical influence on survival in a univariate Cox analysis, were associated with worse overall survival before (HR, 4.83; p < 0.001) and after adjustment for patient age and BMI (HR, 2.18; p = 0.014). Of the quantitative pulmonary vessel features, Ntotal/LSA, N<5mm/LSA, and %VA were correlated with FEV1, FEV1/FVC, and DLCO in all LSAs. The strongest correlation with PFTs was noted at LSA9mm for both Ntotal (FEV1, r = 0.33; FEV1/FVC, r = 0.51) and N<5mm (FEV1, r = 0.35; FEV1/FVC, r = 0.52). For %VA, the association was most evident at LSA18mm (FEV1, r = 0.27; FEV1/FVC, r = 0.47). Significant moderate to strong correlations were consistently observed between the extent of emphysema and quantitative pulmonary vessel features (r = 0.44-0.66; all p < 0.001). CONCLUSIONS: The automated extraction of pulmonary vessels and their quantitative assessment are technically feasible. Various quantitative pulmonary vessel features demonstrated significant relationships with survival and PFT in COPD patients. Of the various quantitative features, the percentage of total VA measured at 18 mm depth from the pleural surface (%VA18mm) and the number of small vessels counted per 10 cm2 of LSA at 9 mm depth from the pleural surface (N<5mm/LSA9mm) had the strongest predictability for the clinical parameters.

Heterogeneous burden of lung disease in smokers with borderline airflow obstruction.

BACKGROUND: The identification of smoking-related lung disease in current and former smokers with normal FEV1 is complex, leading to debate regarding using a ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC) of less than 0.70 versus the predicted lower limit of normal (LLN) for diagnosis of airflow obstruction. We hypothesized that the discordant group of ever-smokers with FEV1/FVC between the LLN and 0.70 is heterogeneous, and aimed to characterize the burden of smoking-related lung disease in this group. METHODS: We compared spirometry, chest CT characteristics, and symptoms between 161 ever-smokers in the discordant group and 940 ever-smokers and 190 never-smokers with normal FEV1 and FEV1/FVC > 0.70 in the SPIROMICS cohort. We also estimated sensitivity and specificity for diagnosing objective radiographic evidence of chronic obstructive pulmonary disease (COPD) using different FEV1/FVC criteria thresholds. RESULTS: The discordant group had more CT defined emphysema and non-emphysematous gas trapping, lower post-bronchodilator FEV1 and FEF25-75, and higher respiratory medication use compared with the other two groups. Within the discordant group, 44% had radiographic CT evidence of either emphysema or non-emphysematous gas trapping; an FEV1/FVC threshold of 0.70 has greater sensitivity but lower specificity compared with LLN for identifying individuals with CT abnormality. CONCLUSIONS: Ever-smokers with normal FEV1 and FEV1/FVC <  0.70 but > LLN are a heterogeneous group that includes significant numbers of individuals with and without radiographic evidence of smoking-related lung disease. These findings emphasize the limitations of diagnosing COPD based on spirometric criteria alone.

When can computed tomography-fissure analysis replace Chartis collateral ventilation assessment in the prediction of patients with emphysema who might benefit from endobronchial valve therapy?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was when can computed tomography-fissure analysis replace Chartis collateral ventilation assessment in the prediction of patients with emphysema who might benefit from endobronchial valve therapy? Twelve papers were chosen to answer the question. The authors, date, journal, country of publication and study type; patient group studied; relevant outcomes and results of these papers were tabulated. Five studies retrospectively compared the prognostic value of 2 methods. They found that when computed tomography-fissure analysis showed an intact fissure more than 95%, both methods were equivalent in correctly predicting a positive response to valve therapy. Concordant results were found in two-thirds of patients, and the additional evaluation with Chartis did not confer a significant advantage. Yet the increasing cost and time to procedure, the different ranges of Chartis findings patterns not correlated with lung volume reduction and the unfeasibility of the measurements (reported in 6-17% of the most series) due to difficult anatomy are additional limitations for its use. Conversely, in patients with fissure integrity between 75% and 90%, Chartis assessment could improve the patient selection, because the computed tomography-fissure analysis alone is unable to predict a successful treatment. In this situation, Chartis had a 31% ability to predict those patients who can be successfully treated. In BeLieVer-HIfi Study, post hoc analysis revealed that the additional use of Chartis for patient selection significantly improved outcomes. Similarly, STELVIO, LIVE and IMPACT studies, where only patients with complete fissure and negative Chartis measurement were treated, showed significant benefits after valve treatment. Finally, in patients with fissure integrity below 75%, the negative predictive value for lobar atelectasis is 100%. Thus, in these patients, it could be futile even considering a Chartis assessment.

Characteristics of patients with increasing COPD assessment test scores within 3 years.

BACKGROUND: The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) is a subjective measure of quality of life. The aim of this study was to examine the characteristics of COPD patients with increasing CAT scores within 3 years. METHODS: Keio University and its affiliate hospitals conducted an observational COPD cohort study over 3 years. St. George's Respiratory Questionnaire (SGRQ) and CAT were completed at baseline and annually thereafter. Patients who had at least 3 CAT scores were included (n = 315). The ΔCAT score/year and ΔSGRQ score/year were calculated by the slope between each of the measures and the date of measurement. RESULTS: The median ΔCAT score/year was 0.4, and ΔCAT score/year was significantly correlated with ΔSGRQ total score/year. Using an annual cut-off CAT score of +2 points, patients who deteriorated (n = 79) were older, had lower %FEV1, and more severe emphysema on computed tomography scan at baseline than patients who did not deteriorate. The baseline value was not a determinant of subsequent changes in the CAT score. Longitudinal changes in the CAT score were positively correlated with those in the SGRQ score. CONCLUSIONS: Old age and severe COPD, not the CAT score at one time point, predicted worsening quality of life.

Assessment of regional emphysema, air-trapping and Xenon-ventilation using dual-energy computed tomography in chronic obstructive pulmonary disease patients.

OBJECTIVES: To compare the parenchymal attenuation change between inspiration/expiration CTs with dynamic ventilation change between xenon wash-in (WI) inspiration and wash-out (WO) expiration CTs. METHODS: 52 prospectively enrolled COPD patients underwent xenon ventilation dual-energy CT during WI and WO periods and pulmonary function tests (PFTs). The parenchymal attenuation parameters (emphysema index (EI), gas-trapping index (GTI) and air-trapping index (ATI)) and xenon ventilation parameters (xenon in WI (Xe-WI), xenon in WO (Xe-WO) and xenon dynamic (Xe-Dyna)) of whole lung and three divided areas (emphysema, hyperinflation and normal) were calculated on virtual non-contrast images and ventilation images. Pearson correlation, linear regression analysis and one-way ANOVA were performed. RESULTS: EI, GTI and ATI showed a significant correlation with Xe-WI, Xe-WO and Xe-Dyna (EI R = -.744, -.562, -.737; GTI R = -.621, -.442, -.629; ATI R = -.600, -.421, -.610, respectively, p < 0.01). All CT parameters showed significant correlation with PFTs except forced vital capacity (FVC). There was a significant difference in GTI, ATI and Xe-Dyna in each lung area (p < 0.01). CONCLUSIONS: The parenchymal attenuation change between inspiration/expiration CTs and xenon dynamic change between xenon WI- and WO-CTs correlate significantly. There are alterations in the dynamics of xenon ventilation between areas of emphysema. KEY POINTS: • The xenon ventilation change correlates with the parenchymal attenuation change. • The xenon ventilation change shows the difference between three lung areas. • The combination of attenuation and xenon can predict more accurate PFTs.

Quantitative computed tomography measurements to evaluate airway disease in chronic obstructive pulmonary disease: Relationship to physiological measurements, clinical index and visual assessment of airway disease.

PURPOSE: To correlate currently available quantitative CT measurements for airway disease with physiological indices and the body-mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) index in patients with chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: This study was approved by our institutional review board (IRB number 2778). Written informed consent was obtained from all subjects. The subjects included 188 current and former cigarette smokers from the COPDGene cohort who underwent inspiratory and expiratory CT and also had physiological measurements for the evaluation of airflow limitation, including FEF25-75%, airway resistance (Raw), and specific airway conductance (sGaw). The BODE index was used as the index of clinical symptoms. Quantitative CT measures included % low attenuation areas [% voxels≤950 Hounsfield unit (HU) on inspiratory CT, %LAA-950ins], percent gas trapping (% voxels≤-856HU on expiratory CT, %LAA -856exp), relative inspiratory to expiratory volume change of voxels with attenuation values from -856 to -950HU [Relative Volume Change (RVC)-856 to -950], expiratory to inspiratory ratio of mean lung density (E/I-ratio MLD), Pi10, and airway wall thickness (WT), luminal diameter (LD) and airway wall area percent (WA%) in the segmental, subsegmental and subsubsegmental bronchi on inspiratory CT. Correlation coefficients were calculated between the QCT measurements and physiological measurements in all subjects and in the subjects with mild emphysema (%LAA-950ins <10%). Univariate and multiple variable analysis for the BODE index were also performed. Adjustments were made for age, gender, smoking pack years, FEF25-75%, Raw, and sGaw. RESULTS: Quantitative CT measurements had significant correlations with physiological indices. Among them, E/I-ratio MLD had the strongest correlations with FEF25-75% (r=-0.648, <0.001) and sGaw (r=-0.624, <0.001) while in the subjects with mild emphysema subsegmental WA% and segmental WA% had the strongest correlation with FEF25-75% (r=-0.669, <0.001) and sGaw (r=-0.638, <0.001), respectively. The multiple variable analyses showed that RVC-856 to -950 was an independent predictor of the BODE index showing the highest R2 (0.468) as an independent variable among the QCT measurements. CONCLUSION: Quantitative CT measurements of gas trapping such as E/I-ratio MLD, correlate better with physiological indices for airway disease than those of airway such as WA% or LD. In mild emphysema, however, quantitative CT measurements of airway correlate better with the physiological indices. RVC-856 to -950 is a predictor of the BODE index.

Sex differences of COPD phenotypes in nonsmoking patients.

BACKGROUND: There is growing evidence about sex-related phenotypes of COPD. However, the sex differences in COPD mainly result from smokers. This study evaluated the sex differences in nonsmoking patients with COPD, focusing on structural changes in the lungs in airway diseases and emphysema. METHODS: Ninety-seven nonsmoking patients, defined as having <1 pack-year of lifetime cigarette smoking, diagnosed with COPD were selected from a Korean COPD cohort. Emphysema extent and mean wall area percentage (WA%) on computed tomography were compared between the male and female groups. RESULTS: The 97 patients with COPD included 62 females and 35 males. Emphysema index was significantly lower (3.5±4.2 vs 6.2±5.7, P<0.01) and mean WA% on computed tomography was significantly higher (71.8%±5% vs 69.4%±5%, P<0.01) in females than in males, after adjusting for age, body mass index, history of biomass exposure, and postbronchodilator forced expiratory volume in 1 second (% of predicted). CONCLUSION: WA% was higher and emphysema extent was lower in nonsmoking females with COPD than in nonsmoking males with COPD. These findings suggest that males may be predisposed to an emphysema phenotype and females may be predisposed to an airway phenotype of COPD.

Low cost biological lung volume reduction therapy for advanced emphysema.

BACKGROUND: Bronchoscopic lung volume reduction (BLVR), using biological agents, is one of the new alternatives to lung volume reduction surgery. OBJECTIVES: To evaluate efficacy and safety of biological BLVR using low cost agents including autologous blood and fibrin glue. METHODS: Enrolled patients were divided into two groups: group A (seven patients) in which autologous blood was used and group B (eight patients) in which fibrin glue was used. The agents were injected through a triple lumen balloon catheter via fiberoptic bronchoscope. Changes in high resolution computerized tomography (HRCT) volumetry, pulmonary function tests, symptoms, and exercise capacity were evaluated at 12 weeks postprocedure as well as for complications. RESULTS: In group A, at 12 weeks postprocedure, there was significant improvement in the mean value of HRCT volumetry and residual volume/total lung capacity (% predicted) (P-value: <0.001 and 0.038, respectively). In group B, there was significant improvement in the mean value of HRCT volumetry and (residual volume/total lung capacity % predicted) (P-value: 0.005 and 0.004, respectively). All patients tolerated the procedure with no mortality. CONCLUSION: BLVR using autologous blood and locally prepared fibrin glue is a promising method for therapy of advanced emphysema in term of efficacy, safety as well as cost effectiveness.

European Non-Communicable Respiratory Disease Research, 2002-13: Bibliometric Study of Outputs and Funding.

This study was conducted in order to map European research in chronic respiratory diseases (CRDs). It was intended to assist the European Commission and other research funders to identify gaps and overlaps in their portfolios, and to suggest ways in which they could improve the effectiveness of their support and increase the impact of the research on patient care and on the reduction of the incidence of the CRDs. Articles and reviews were identified in the Web of Science on research in six non-communicable respiratory diseases that were published in 2002-13 from 31 European countries. They represented only 0.8% of biomedical research output but these diseases accounted for 4.7% of the European disease burden, as measured by Disability-Adjusted Life Years (DALYs), so the sub-field is seriously under-researched. Europe is prominent in the sub-field and published 56% of the world total, with the UK the most productive and publishing more than France and Italy, the next two countries, combined. Asthma and Chronic Obstructive Pulmonary Disease (COPD) were the diseases with the most publications and the highest citation rates. They also received the most funding, with around two acknowledgments per paper (in 2009-13), whereas cystic fibrosis and emphysema averaged only one. Just over 37% of papers had no specific funding and depended on institutional support from universities and hospitals.

COMPARATIVE ASSESSMENT OF THORACOSCOPY AND DESTRUCTION OF PULMONARY BULLAS COMBINED WITH PLEURODESIS AND PLEURECTOMY.

The article presents the results of thoracoscopic surgeries in case of bullous emphysema of the lung in 88 patients. The patients have been divided into 2 groups according to the method of treatment: 1) destruction of pulmonary bullas and pleurodesis using diathermic electrocoagulation (42 people); 2) destruction of pulmonary bullas and subtotal pleurectomy (47 people). The operative periods weren't statistically differentiated in patient's groups. The volume of hemorrhage and exudation period from the pleural cavity were significantly higher in patient's group, where patients underwent pleurectomy. However, lung spreading terms and ending of air leakage, periods of drains removal from the pleural cavity, hospital stay and rate of pneumothorax recurrence were considerably smaller in the group without application of pleurodesis.

Influence of pulmonary emphysema on COPD assessment test-oriented categorization in GOLD document.

BACKGROUND: The COPD assessment test (CAT) score is a key component of the multifactorial assessment of COPD in the Global initiative for chronic Obstructive Lung Disease (GOLD) guidelines of 2014. Nevertheless, little is known regarding the differences among COPD categories in terms of clinical parameters such as pulmonary function or radiological findings. Thus, our aims in this study were to evaluate the associations between CAT scores and pulmonary clinical parameters, and to investigate factors that could discriminate between a "less symptomatic group" (categories A and C) and a "more symptomatic group" (categories B and D) among stable COPD patients. METHODS: We enrolled 200 outpatients at Chiba University Hospital. Study subjects were assessed by CAT, pulmonary function testing, and multidetector computed tomography (MDCT). We assessed possible correlations between these indices. RESULTS: CAT scores were negatively correlated with percentage of the forced expiratory volume in 1 second predicted value (FEV1 %predicted) and percentage of the diffusing capacity for carbon monoxide per liter of lung volume predicted value (DLCO/VA [%predicted]) results and positively correlated with low attenuation volume percentage (LAV%) and residual volume to total lung capacity ratios (RV/TLC). In the "more symptomatic group" (category B or D), the mean DLCO/VA (%predicted) was significantly lower and the mean LAV% and RV/TLC was significantly higher than those in the "less symptomatic group" (category A or C), respectively. Interestingly, those in category B had higher mean LAV% compared to those in category C. CONCLUSION: CAT scores were significantly correlated with pulmonary function parameters and emphysematous changes on MDCT. The new GOLD classification system would be a step toward a phenotypic approach, especially taking into account the degree of emphysema and hyperinflation.

Lobe-based computed tomography assessment of airway diameter, airway or vessel number, and emphysema extent in relation to the clinical outcomes of COPD.

OBJECTIVE: The aim of this study was to evaluate the relationship between computed tomography assessed lobe-based lung parameters and the clinical outcomes of patients with chronic obstructive pulmonary disease (COPD), including the frequency of exacerbation and annual change in forced expiratory volume in 1 second (FEV1). PATIENTS AND METHODS: We studied 65 patients with COPD. We reconstructed computed tomography images to trace the bronchial tree from right B1 to B10 and created 3 cm circle images around the airways exactly perpendicular to the airway axis in the central, middle, and peripheral zones of the bronchi. The number of airways and vessels, airway inner diameter and area of emphysema in the circles were calculated for each segment. Then, we analyzed the relationships between the lobe-based image parameters and the frequency of exacerbation and annual decline in the FEV1. In addition, we assessed the effects of proximal airway lumen-obliterated emphysema (ALOE) on these clinical features. RESULTS: The airway diameter was not associated with the frequency of exacerbation or annual decline in FEV1. Among the structural parameters, lower lobe emphysema was most associated with the frequency of exacerbation. The reductions in the number of airways and vessels in total lobe were associated with the annual decline in FEV1. The subgroup of patients with ALOE demonstrated lower FEV1 and more frequent exacerbation than those without ALOE. CONCLUSION: Lower lobe emphysema predicts frequent COPD exacerbation, whereas the annual decline in FEV1 is associated with the number of airways and vessels in total lobe.

Assessment of volume reduction effect after lung lobectomy for cancer.

BACKGROUND: Lung lobectomy results in an unexpected improvement of the remaining lung function in some patients with moderate-to-severe emphysema. Because the lung function is the main limiting factor for therapeutic decision making in patients with lung cancer, it may be advantageous to identify patients who may benefit from the volume reduction effect, particularly those with a poor functional reserve. METHODS: We measured the regional distribution of the emphysematous lung and normal lung using quantitative computed tomography in 84 patients undergoing lung lobectomy for cancer between January 2010 and December 2012. The volume reduction effect was diagnosed using a combination of radiologic and spirometric parameters. RESULTS: Eight patients (10%) were favorably affected by the volume reduction effect. The forced expiratory volume in one second increased postoperatively in these eight patients, whereas the forced vital capacity was unchanged, thus resulting in an improvement of the airflow obstruction postoperatively. This improvement was not due to a compensatory expansion of the remaining lung but was associated with a relative decrease in the forced end-expiratory lung volume. According to a multivariate analysis, airflow obstruction and the forced end-expiratory lung volume were independent predictors of the volume reduction effect. CONCLUSIONS: A combined assessment using spirometry and quantitative computed tomography helped to characterize the respiratory dynamics underlying the volume reduction effect, thus leading to the identification of novel predictors of a volume reduction effect after lobectomy for cancer. Verification of our results by a large-scale prospective study may help to extend the indications for lobectomy in patients with oncologically resectable lung cancer who have a marginal pulmonary function.