TRITRIAL: The Impact of Fixed Triple Therapy with Beclometasone/Formoterol/Glycopyrronium on Health Status and Adherence in Chronic Obstructive Pulmonary Disease in an Italian Context of Real Life

Purpose

The TRITRIAL study assessed the effects of beclometasone dipropionate/formoterol fumarate/glycopyrronium (BDP/FF/G) fixed combination in patients with chronic obstructive pulmonary disease (COPD) in a real-world setting, focusing on patient's experience and perspective through the use of patients reported outcomes.

Patients and Methods

TRITRIAL was a multicenter, prospective, observational study conducted on patients with moderate-severe COPD treated with BDP/FF/G fixed therapy for 12 months. The main objective was to evaluate the impact of BDP/FF/G on health status through the COPD Assessment Test (CAT) score. Additional assessments included adherence and satisfaction, measured by the TAI-10/12 questionnaire and a specifically designed eight-item questionnaire, quality of life through the EQ-5D-5L test, sleep quality through the COPD and Asthma Sleep Impact Scale (CASIS), as well as safety and disease-related outcomes.

Results

Data from 655 patients were analyzed in the study. The mean total CAT score significantly improved (from 22.8 at baseline to 18.1 at 6 months and 16.5 at 12 months; p < 0.0001), as well as all the eight CAT sub-items, which decreased on average by 0.5-0.9 points during the study. Adherence and usability of the inhaler also improved during the study, with a decrease in poor compliance (from 30.1% to 18.3%) and an increase in good compliance (from 51.8% to 58.3%) according to the TAI score. Patients also benefited from significantly improved quality of life (EQ Index from 0.70 to 0.80; EQ-5D VAS score from 55.1 to 63.1) and sleep quality (CASIS score from 41.1 to 31.8). Finally, patients reported a significant reduction in exacerbation during the study.

Conclusion

TRITRIAL showed that the BDP/FF/G fixed combination is effective and safe in patients with moderate-severe COPD and poorly controlled disease, improving patients' HRQoL, sleep quality, adherence and inhaler usability and reducing COPD symptoms and the risk of exacerbation in a real-life setting.

Severe Asthma Network Italy Definition of Clinical Remission in Severe Asthma: A Delphi Consensus

Severe asthma affects about 10% of the population with asthma and is characterized by low lung function and a high count of blood leukocytes, mainly eosinophils. Various definitions are used in clinical practice and in the literature to identify asthma remission: clinical remission, inflammatory remission, and complete remission. This work highlights a consensus for asthma remission using a Delphi method. In the context of the Severe Asthma Network Italy, which accounts for 57 severe asthma centers and more than 2,200 patients, a board of six experts drafted a list of candidate statements in a questionnaire, which has been revised to minimize redundancies and ensure clear and consistent wording for the first round (R1) of the analysis. Thirty-two statements were included in the R1 questionnaire and then submitted to a panel of 80 experts, which used a 5-point Likert scale to measure agreement regarding each statement. Then, an interim analysis of R1 data was performed, and items were discussed and considered to produce a consistent questionnaire for round 2 (R2) of the analysis. Then, the board set the R2 questionnaire, which included only important topics. Panelists were asked to vote on the statements in the R2 questionnaire afterward. During R2, the criteria of complete clinical remission (the absence of the need for oral corticosteroids, symptoms, exacerbations or attacks, and pulmonary function stability) and those of partial clinical remission (the absence of the need for oral corticosteroids, and two of three criteria: the absence of symptoms, exacerbations or attacks, and pulmonary stability) were confirmed. This Severe Asthma Network Italy Delphi analysis defined a valuable and independent tool that is easy to use, to test the efficacy of different treatments in patients with severe asthma enrolled into the SANI registry.

Pulmonary emphysema and coronary artery calcifications at baseline LDCT and long-term mortality in smokers and former smokers of the ITALUNG screening trial

OBJECTIVES

Cardiovascular disease (CVD), lung cancer (LC), and respiratory diseases are main causes of death in smokers and former smokers undergoing low-dose computed tomography (LDCT) for LC screening. We assessed whether quantification of pulmonary emphysematous changes at baseline LDCT has a predictive value concerning long-term mortality.

METHODS

In this longitudinal study, we assessed pulmonary emphysematous changes with densitometry (volume corrected relative area below - 950 Hounsfield units) and coronary artery calcifications (CAC) with a 0-3 visual scale in baseline LDCT of 524 participants in the ITALUNG trial and analyzed their association with mortality after 13.6 years of follow-up using conventional statistics and a machine learning approach.

RESULTS

Pulmonary emphysematous changes were present in 32.3% of subjects and were mild (6% ≤ RA950 ≤ 9%) in 14.9% and moderate-severe (RA950 > 9%) in 17.4%. CAC were present in 67% of subjects (mild in 34.7%, moderate-severe in 32.2%). In the follow-up, 81 (15.4%) subjects died (20 of LC, 28 of other cancers, 15 of CVD, 4 of respiratory disease, and 14 of other conditions). After adjusting for age, sex, smoking history, and CAC, moderate-severe emphysema was significantly associated with overall (OR 2.22; 95CI 1.34-3.70) and CVD (OR 3.66; 95CI 1.21-11.04) mortality. Machine learning showed that RA950 was the best single feature predictive of overall and CVD mortality.

CONCLUSIONS

Moderate-severe pulmonary emphysematous changes are an independent predictor of long-term overall and CVD mortality in subjects participating in LC screening and should be incorporated in the post-test calculation of the individual mortality risk profile.

KEY POINTS

• Densitometry allows quantification of pulmonary emphysematous changes in low-dose CT examinations for lung cancer screening. • Emphysematous lung density changes are an independent predictor of long-term overall and cardio-vascular disease mortality in smokers and former smokers undergoing screening. • Emphysematous changes quantification should be included in the post-test calculation of the individual mortality risk profile.

Lung vascular changes as biomarkers of severity in systemic sclerosis-associated interstitial lung disease

OBJECTIVES

It has recently become possible to assess lung vascular and parenchymal changes quantitatively in thoracic CT images using automated software tools. We investigated the vessel parameters of patients with SSc, quantified by CT imaging, and correlated them with interstitial lung disease (ILD) features.

METHODS

SSc patients undergoing standard of care pulmonary function testing and CT evaluation were retrospectively evaluated. CT images were analysed for ILD patterns and total pulmonary vascular volume (PVV) extents with Imbio lung texture analysis. Vascular analysis (volumes, numbers and densities of vessels, separating arteries and veins) was performed with an in-house developed software. A threshold of 5% ILD extent was chosen to define the presence of ILD, and commonly used cut-offs of lung function were adopted.

RESULTS

A total of 79 patients [52 women, 40 ILD, mean age 56.2 (s.d. 14.2) years, total ILD extent 9.5 (10.7)%, PVV/lung volume % 2.8%] were enrolled. Vascular parameters for total and separated PVV significantly correlated with functional parameters and ILD pattern extents. SSc-associated ILD (SSc-ILD) patients presented with an increased number and volume of arterial vessels, in particular those between 2 and 4 mm of diameter, and with a higher density of arteries and veins of <6 mm in diameter. Considering radiological and functional criteria concomitantly, as well as the descriptive trends from the longitudinal evaluations, the normalized PVVs, vessel numbers and densities increased progressively with the increase/worsening of ILD extent and functional impairment.

CONCLUSION

In SSc patients CT vessel parameters increase in parallel with ILD extent and functional impairment, and may represent a biomarker of SSc-ILD severity.

Influence of allergic status and nasal polyposis on long-term Benralizumab response in eosinophilic severe asthma

Objective

It is unclear whether Benralizumab effectiveness in severe eosinophilic asthma can be influenced by nasal polyposis (NP) or allergic status associations. We evaluated whether Benralizumab long-term efficacy in asthma outcomes could be different in subjects with atopy (SAEA) compared to the effectiveness in those without allergies (SNAEA) and in individuals with NP compared to those without NP.

Methods

This observational retrospective study considered 95 consecutive patients divided into allergic (SAEA; n:65[68.4%]; skin prick tests positive [SPT] and/or IgE values ≥100 UI/mL), and non-allergic (SNAEA; n:30[31.6%], SPT negative and normal IgE levels<100 UI/mL). Overall population was also divided into two groups according to NP presence (NP+:39[41%] and NP-:56[59%]). Benralizumab treatment mean was19.7±7.2 months (range 12-35).

Results

No differences in Benralizumab effectiveness were found in asthma outcomes in patients with/without NP. SNOT-22 improvement was higher in NP+ (-22±24) compared to NP- groups (6.33±15.5;p=0.055). FEV1 (16.33±19.22%), ACT(7.45±3.95) increases and frequency of SABA use (3.37±4.99) reduction were higher in SAEA compared to what obtained in non-allergic subjects (FEV1:8.15±15.6%,p=0.043; ACT:4.89±3.57,p=0.005; SABA use:-1.16±1.84;p=0.015). 93.8% of SAEA patients whereas only 72.2% of SNAEA individuals reduced OC doses at least half after Benralizumab (p=0.035). These results were partially confirmed by linear regression models showing associations between allergic status and FEV1, ACT and SABA use changes (β=8.37;p=0.048, β=2.056;p=0.033 and β=-2.184;p=0.042 respectively).

Conclusion

Benralizumab effectiveness in asthma appears to be independent of NP presence. The allergic eosinophilic disease, compared to just eosinophilic asthma, may be a more severe phenotype. Benralizumab may have greater efficacy in SAEA on some outcomes.

Severe asthma and long-term Benralizumab effectiveness in real-life

OBJECTIVE

Long-term efficacy of Benralizumab in real life is not clearly known. We assessed the long-term effectiveness persistence to anti-IL-5R treatment in a group of severe eosinophilic asthmatics.

PATIENTS AND METHODS

We retrospectively analyzed 95 individuals affected by severe asthma (36 males  ̶ 37.9%; mean age 58.1 ± 12.2) treated with Benralizumab (mean time 19.7 ± 7.2 months, range 12-35). Outcomes were evaluated at the beginning and at the end of patients' treatment periods.

RESULTS

Mean baseline blood eosinophils were 897.5 ± 720.1 cells/μL (11 ± 5.6%) decreasing to 7.4 ± 20.6 cells/μL (0.97 ± 0.26%; p < 0.0001) after Benralizumab. FENO likewise decreased from 63.9 ± 68.4 to 28.4 ± 23.6 ppb, while FEV1% significantly improved (p < 0.0001). Mean FEF25-75 also increased from 45.8 ± 24.6% to 60.7 ± 24.6%, whereas RAW dropped from 202.15 ± 109.6% to 135.2 ± 54.75% (p < 0.0001). Also, lung volumes greatly decreased. ACT/ACQ significantly improved, while exacerbations number fell from 4.1 ± 2.4, before anti-IL-5R, to 0.33 ± 0.77, after treatment (p < 0.0001). Rhinitis severity levels and SNOT-22 also changed favorably. Patients that took long-term OCs were 71.6% before treatment, decreasing to 23.2% after Benralizumab (p < 0.0001), with an OCs dose reduction from 14.8 ± 8.9 to 1.45 ± 2.8 mg/day (p < 0.0001). 51.6% of subjects used SABA as needed before Benralizumab, falling to 4.2% after treatment. Several patients showed a reduction of ICS doses, SABA use and maintenance therapy step-down. Clinical/biological response with anti-IL-5R remained constant or even improved in terms of exacerbations or maintenance therapy reductions over time. On the contrary, FEF25-75% improvement slowed down in the long-term. No relationship was found between baseline blood eosinophil number and therapeutic response.

CONCLUSIONS

Long-term Benralizumab effectiveness persistence in all outcomes in real life was confirmed.

Patients and doctors group meetings: an innovative way to explore severe asthma backstage

Severe asthma patients' life is heavily influenced by the disease, which has impact on personal and professional choices or general lifestyle. Despite the available tools to help physicians investigating the patient-reported outcomes there is a need for a more standardised and structured approach to include the evaluation of quality of life together with the emotions of patients into the routine clinical interaction. We hereby report the use of an active listening and insight approach to understand the emotions of patients with severe asthma through dedicated in-person meetings involving a group of patients with their doctors, caregivers and an external moderator. The initiative "Patients insight meeting" was organized within 17 specialist referral centres for severe asthma in Italy in 2019 and involved 149 patients. Insights related to 4 different items were collected and a task force composed by the external moderators produced a general report including the suggestions from the participating centres. This experience of group-meetings involving both patients and doctors together represents an innovative way to investigate real life experience and the emotions of asthmatic patients, highlighting unmet needs related to patient's experience of his/her disease that need to be included in severe asthmatics' management strategy.

Discriminant Profiles of Volatile Compounds in the Alveolar Air of Patients with Squamous Cell Lung Cancer, Lung Adenocarcinoma or Colon Cancer

The objective of the present work was to analyze volatile compounds in alveolar air in patients with squamous cell lung cancer, lung adenocarcinoma or colon cancer, to prepare algorithms able to discriminate such specific pathological conditions. The concentration of 95 volatile compounds was measured in the alveolar air of 45 control subjects, 36 patients with lung adenocarcinoma, 25 patients with squamous cell lung cancer and 52 patients with colon cancer. Volatile compounds were measured with ion molecule reaction mass spectrometry (IMR-MS). An iterated least absolute shrinkage and selection operator multivariate logistic regression model was used to generate specific algorithms and discriminate control subjects from patients with different kinds of cancer. The final predictive models reached the following performance: by using 11 compounds, patients with lung adenocarcinoma were identified with a sensitivity of 86% and specificity of 84%; nine compounds allowed us to identify patients with lung squamous cell carcinoma with a sensitivity of 88% and specificity of 84%; patients with colon adenocarcinoma could be identified with a sensitivity of 96% and a specificity of 73% using a model comprising 13 volatile compounds. The different alveolar profiles of volatile compounds, obtained from patients with three different kinds of cancer, suggest dissimilar biological–biochemistry conditions; each kind of cancer has probably got a specific alveolar profile.

Mepolizumab Effectiveness and Allergic Status in Real Life

BACKGROUND

It is not clear whether mepolizumab is differently effective in allergic and nonallergic severe eosinophilic asthmatics (SEA) in real life.

OBJECTIVE

We tested mepolizumab effectiveness in allergic/nonallergic SEA in real life. A strict criterion to identify the 2 phenotypes was used.

METHOD

We retrospectively considered 134 consecutive patients divided into allergic, with a positivity to at least 1 allergen to prick tests and/or IgE values ≥100 UI/mL (severe allergic eosinophilic asthma [SAEA]; n: 97-72.4%), and nonallergic, with no prick test results and normal IgE levels <100 UI/mL (severe nonallergic eosinophilic asthma [SNAEA]; n: 37-27.6%). They had taken mepolizumab for at least 6 months.

RESULTS

After 10.9 ± 3.7 months, improvements in FEV1%, FEF25-75%, exacerbation numbers, blood eosinophil (BE) counts, fractional exhaled nitric oxide (FENO) (ppb), percentages of patients that stopped/reduced short-acting β2-agonists (SABAs) or oral corticosteroid (OC), observed after treatment, were similar in both groups. Only Asthma Control Test (ACT) increases were higher in SNAEA (8 [5-9]) than in SAEA (5 [2.5-8.5]; p = 0.016). However, no differences were found after treatment in percentages of subjects with ACT ≥20, as well as with FEV1 >80%, FEF25-75 >65%, exacerbations ≤2, BE <300 cells/µL, and FENO <25 ppb between SAEA and SNAEA. Besides, no significant relationships were found, comparing SNAEA with SAEA, for FEV1% (β = -0.110; p = 0.266), FEF25-75% (β = -0.228; p = 0.06), BE counts (β = -0.012; p = 0.918), FENO (β = 0.234; p = 0.085), ACT (β = 0.046; p = 0.660), and exacerbations (β = -0.070; p = 0.437). No different associations between lung function and SNAEA occurrence when compared to SAEA condition (FEV1 >80%: OR = 1.04 [95% CI: 0.43-2.55], p = 0.923; FEF25-75 >65%: OR = 0.41 [95% CI: 0.08-2.03], p = 0.272) were detected. Neither all other parameters, such as ACT >20 (OR = 0.73 [95% CI: 0.32-1.63], p = 0.440), presence of exacerbations (OR = 1.35 [95% CI: 0.55-3.27], p = 0.512), SABA discontinuation (OR = 1.16 [95% CI: 0.40-3.39], p = 0.790), and OC cessation/reduction (OR = 3.44 [95% CI: 0.40-29.27], p = 0.258), were differently associated with 1 or the other phenotype.

CONCLUSION

Mepolizumab can be considered as a valid therapeutic choice for either allergic or nonallergic SEA in real life.

Oral CorticoSteroid sparing with biologics in severe asthma: A remark of the Severe Asthma Network in Italy (SANI)

According to the data derived from several national and international registries, including SANI (Severe Asthma Network Italy), and considering the strong impact that frequent or regular use of oral corticosteroid has on quality of life (QoL) of severe asthmatics, as well as on the costs for managing corticosteroid-related diseases, oral corticosteroid sparing up to withdrawal should be considered a primary outcome in the management of severe asthma. New biologics have clearly demonstrated that this effect is possible, with concomitant reduction in the rate of exacerbations and in symptom control. Then, there is no reason for using so frequently oral corticosteroid before having explored all alternatives currently available for a large part of severe asthmatics.

Quantitative analysis of pulmonary vasculature in systemic sclerosis at spirometry-gated chest CT

OBJECTIVE

To prospectively investigate whether differences in pulmonary vasculature exist in systemic sclerosis (SSc) and how they are distributed in patients with different pulmonary function.

METHODS

Seventy-four patients with SSc undergoing chest CT scan for interstitial lung disease (ILD) screening or follow-up were prospectively enrolled. A thorough clinical, laboratory and functional evaluation was performed the same day. Chest CT was spirometry gated at total lung capacity and images were analysed by two automated software programs to quantify emphysema, ILD patterns (ground-glass, reticular, honeycombing), and pulmonary vascular volume (PVV). Patients were divided in restricted (FVC% <80, DLco%<80), isolated DLco% reduction (iDLco- FVC%≥80, DLco%<80) and normals (FVC%≥80, DLco%≥80). Spearman ρ, Mann-Whitney tests and logistic regressions were used to assess for correlations, differences among groups and relationships between continuous variables.

RESULTS

Absolute and lung volume normalised PVV (PVV/LV) correlated inversely with functional parameters and positively with all ILD patterns (ρ=0.75 with ground glass, ρ=0.68 with reticular). PVV/LV was the only predictor of DLco at multivariate analysis (p=0.007). Meanwhile, the reticular pattern prevailed in peripheral regions and lower lung thirds, PVV/LV prevailed in central regions and middle lung thirds. iDLco group had a significantly higher PVV/LV (2.2%) than normal (1.6%), but lower than restricted ones (3.8%).

CONCLUSIONS

Chest CT in SSc detects a progressive increase in PVV/LV as DLco decreases. Redistribution of perfusion to less affected lung regions rather than angiogenesis nearby fibrotic lung may explain the results. Further studies to ascertain whether the increase in PVV/LV reflects a real increase in blood volume are needed.

SAT0553 QUANTITATIVE ANALYSIS OF IMAGING FEATURES AT CHEST CT OF PULMONARY ARTERIAL AND VENOUS COMPONENTS IN SYSTEMIC SCLEROSIS-INTERSTITIAL LUNG DISEASE (SSc-ILD)

Background:

Interstitial lung disease (ILD) and pulmonary arterial hypertension carry a negative impact on SSc prognosis. Chest CT is the gold standard in assessing ILD and helps in evaluating associated vascular involvement.

Objectives:

As qualitative analysis of CT scans is limited by low reproducibility and time constraints, we aimed at evaluating parenchymal and vascular features in SSc-ILD by quantitative analysis (QA) of CT scans and testing the relationship with clinical-functional data.

Methods:

We prospectively enrolled 80 patients who underwent PFTs and chest CT scan spirometry gated at TLC on the same day. Clinical, lung functional and diffusion data, as well as disability indexes were collected. CT images were analyzed by a computational platform for texture analysis of ILD patterns (CALIPER), through Imbio LTA. It quantified the extent of normal pattern (NP %), ground glass opacities (GG %), reticulation (RET %), honeycombing (HC %), total ILD extent (ILD EXT %) and hyperlucent (HL %). Low density areas, representing emphysematous area, were also quantified (LDA %). For lung vessel analysis, a software program developed by the Ludwig Boltzmann Institute for Lung Vascular Research was used. This software determined total, arterial, and venous vascular volumes (TV, AV, VV), and relative volumes (TV%, AV%, VV%), as well as density and number for total, arterial and venous vessels.

Results:

43/80 patients/CT scans were eligible for both software analyses, while 36/43 for arterial and venous separation. TV% and total vessel density were correlated positively with mRSS and negatively with %FVC (r=-0.537 and r=-0.382) and %TLC (r=-0.511 and r=-0.648), while vessel tortuosity correlated positively with %DLco. This was confirmed when separately analyzing arterial vessels, while VV% negatively correlated with %FVC, %TLC and %DLco. There was a positive correlation between %ILD patterns and %vascular volumes, being significant for TV%-AV%, total vessels and arterial density. Conversely, %ILD patterns were negatively correlated with VV and number of veins detected, despite positive correlation between VV% and ILD_EXT%. When clustering patients according to %FVC and %DLco with 80% normal cutoff, %FVC allowed clustering according to significantly different ILD patterns extents and vascular features, while %DLCO for vascular features only. Moreover, the consecutive addition of functional impairment and worsening of ILD (from both normal %FVC and %Dlco, to %DLco impairment only to both %FVC and %Dlco impairment), there was a significant increase in %TV, % AV and %VV, with the exception of decrease in %VV and venous density in patients with double impairment versus DLco single impairment.

Conclusion:

This is the first study showing in SSc a direct correlation between ILD and the increase in lung vascular volume, which is characterized by increase in arterial volume and density and reduction in venous volume and number. These results might be explained by the reduction of pulmonary volume due to fibrosis. However, also a para-physiological mechanism of redistribution of blood flow in lung areas, less involved by ILD, might be considered. Further studies on lung vessel quantification and distribution are ongoing.

Disclosure of Interests:

Cosimo Bruni Speakers bureau: Actelion, Eli Lilly, Mariaelena Occhipinti Consultant of: Imbio, Gianna Camiciottoli: None declared, Maurizio Bartolucci: None declared, Michael Pienn: None declared, Gemma Lepri: None declared, Alessio Fabbrizzi: None declared, Alessandra Tottoli: None declared, Giuglia Ciardi: None declared, Dilia Giuggioli: None declared, Giovanna CUOMO: None declared, Francesco Masini: None declared, Horst Olschewski: None declared, Federico Lavorini: None declared, Linda Calistri: None declared, Marco Matucci-Cerinic Grant/research support from: Actelion, MSD, Bristol-Myers Squibb, Speakers bureau: Acetelion, Lilly, Boehringer Ingelheim

OP0181 FUNCTIONAL CUT-OFFS TO DISTINGUISH PULMONARY VASCULAR AND PARENCHYMAL INVOLVEMENT IN SYSTEMIC SCLEROSIS (SSC): A QUANTITATIVE ANALYSIS OF IMAGING FEATURES AT CHEST COMPUTED TOMOGRAPHY (CT)

Background:

Interstitial lung disease (ILD) and pulmonary arterial hypertension represent the most frequent causes of morbidity and mortality in SSc, with chest CT representing the gold standard in ILD assessment, while FVC and DLco allow functional assessment.

Objectives:

As qualitative analysis of given chest CT scans is hampered by low reproducibility, we aimed to perform a quantitative analysis (QA) of CT scans able to investigate the parenchymal and vascular features in SSc-ILD and thus testing the relationship with clinical-functional data.

Methods:

We prospectively enrolled 80 patients who underwent PFTs and spirometry-gated chest CT scan at TLC on the same day. Clinical, lung functional and diffusion data, as well as disability indexes were collected. CT images were analyzed by a computational platform for texture analysis of ILD patterns (CALIPER) through Imbio LTA. It quantified the extent of normal lung (%N), ground-glass opacities (%GG), reticulation (%RET), honeycombing (%HC), hyperlucent (%HL), absolute (PVV, cm3) and normalized (PVV/LV, %) pulmonary vascular volumes. Cut-offs of normality for %FVC and %DLco of 80% and 70% were tested to differentiate parenchymal and vascular features.

Results:

73 patients/CT scans were eligible for both software analyses. CALIPER showed GG% as the most frequent radiological pattern (mean 5.5±10.4%). %FVC and % TLC negatively correlated with all ILD patterns, while %DLco with RET% only; PVV and PVV/LV negatively correlated with %FVC and %TLC, while %DLco with PVV/LV only. Positive correlations were found between all ILD patterns and vascular volumes (Table 1).

LV (cm3)%N%GG%RET%HC%HLPVV (cm3)% PVV/LVFVC%r.60-.19-.40-.34-.30.35-.26-.44p<.001-<.001.004.01.003.04<.001FEV1%r.58-.02-.38-.25-.24.23-.35-.49p<.001-.002.04.05-.004<.001FEV1/FVCr-.16.33.22.16.21-.35-.15-.08p-.02------TLC%r.71-.14-.42-.37-.48.40-.43-.64p<.001-.001.01<.001.002<.001<.02DLco%r.38-.05-.21-.31-.22.30-.21-.33p.01--.01---.006FVC/DLcor.03-.08-.06-.003-.09.08-.06-.08p--------

Cut-offs equal to 80 for %FVC and 70 for %DLco distinguished both parenchymal and vascular features, while 80 for %DLco characterized vascular features only. These results were confirmed also when patients were stratified according to absent/single/combined %FVC and %DLCO impairments with 80% cut-offs (Table 2).

FVC<80%FVC ≥80%pDLco<80%DLco ≥80%pDLco <70%DLco ≥70%p%N82.7 (9.6)86.2 (14.7)-86.6 (12.7)80.8 (15.8)-84.1 (13.9)86.4 (13.5)-%GG10.3 (8.9)2.4 (3.9)<.0015.0 (6.7)3.9 (6.9)-6.2 (7.5)2.4 (4.8).002%RET2.9 (2.9)0.8 (1.3)<.0011.6 (2.1)0.7 (0.9)-1.9 (2.4)0.6 (0.8).007%HC0.4 (0.6)0.1 (0.1)<.0010.2 (0.3)0.1 (0.1)-0.2 (0.4)0.05 (0.2).010%HL3.6 (6.8)8.9 (12.1)-5.4 (8.8)14.1 (15.4).0506.3 (10.1)9.2 (12.7)-PVV125.6 (39.1)90.9 (26.9)<.001101.9 (34.8)84.7 (19.4).016106.9 (38.3)87.5 (20.5).012PVV/LV3.8 (1.6)2.0 (0.7)<.0012.51 (1.3)1.7 (0.6).0022.76 (1.4)1.83 (0.6).001

Conclusion:

In SSc a cut-off at 80 for %DLco may help identifying vascular changes as automatically assessed on chest CT scan, without any underlying ILD. The 80% cut-off for %DLco may be proposed to identify isolated vascular involvement, while %FVC at 80% or %DLco at 70% to identify significant parenchymal involvement. These results need to be confirmed in larger multi-centric cohorts.

Disclosure of Interests:

Cosimo Bruni Speakers bureau: Actelion, Eli Lilly, Mariaelena Occhipinti Consultant of: Imbio, Gianna Camiciottoli: None declared, Maurizio Bartolucci: None declared, Gemma Lepri: None declared, Alessio Fabbrizzi: None declared, Alessandra Tottoli: None declared, Anna Bassetto: None declared, Giuglia Ciardi: None declared, Dilia Giuggioli: None declared, Giovanna CUOMO: None declared, Francesco Masini: None declared, Federico Lavorini: None declared, Linda Calistri: None declared, Marco Matucci-Cerinic Grant/research support from: Actelion, MSD, Bristol-Myers Squibb, Speakers bureau: Acetelion, Lilly, Boehringer Ingelheim

Mepolizumab effectiveness on small airway obstruction, corticosteroid sparing and maintenance therapy step-down in real life

BACKGROUND

Mepolizumab (MEP) has been recently introduced to treat severe eosinophilic asthma. Trials have demonstrated a significant effectiveness in this asthma phenotype. We evaluated MEP efficacy on lung function, symptoms, asthma exacerbations, biologic markers, steroid dependence and controller treatment level in real-life.

METHODS

We retrospectively analyzed 134 severe asthmatics (61 males; mean age 58.3 ± 11; mean FEV₁%:72 ± 21), treated with MEP for at least 6 months (mean duration:10.9 ± 3.7 months).

RESULTS

FEV₁% improved significantly after MEP. Mean FEF_25-75 also increased from 37.4 ± 25.4% to 47.2 ± 27.2% (p < 0.0001). Mean baseline blood eosinophil level was 712 ± 731/μL (8.4 ± 5.2%) decreasing to 151 ± 384/μL (1.6 ± 1.6%) (p < 0.0001), FENO levels decreased likewise. MEP treatment also led to a significant ACT improvement (mean pre:14.2 ± 4.4; mean post:20.5 ± 28) and exacerbations significantly fell from 3.8 ± 1.9 to 0.8 ± 1.1 (p < 0.0001). 74% of patients were steroid-dependent before MEP. 45.4% and 46.4% of them showed a suspension and dose reduction respectively (p < 0.0001). A significant number reduced also ICS doses. Only 67% of subjects used SABA as needed before MEP, falling to 20% after MEP. About 40% of patients highlighted a maintenance therapy step-down. Subjects showing an omalizumab treatment failure before MEP had a similar positive response when compared with omalizumab untreated patients.

CONCLUSION

In real-life, MEP improved significantly all outcomes even small airway obstruction, suggesting its possible role also in distal lung region treatment. Furthermore, it demonstrated its high effectiveness in OC/ICS-sparing, in reducing SABA as needed and in stepping-down maintenance therapy. MEP is a valid alternative for patients with previous omalizumab treatment failure.

Emphysematous and Nonemphysematous Gas Trapping in Chronic Obstructive Pulmonary Disease: Quantitative CT Findings and Pulmonary Function

Purpose To identify a prevalent computed tomography (CT) subtype in patients with chronic obstructive pulmonary disease (COPD) by separating emphysematous from nonemphysematous contributions to total gas trapping and to attempt to predict and grade the emphysematous gas trapping by using clinical and functional data. Materials and Methods Two-hundred and two consecutive eligible patients (159 men and 43 women; mean age, 70 years [age range, 41-85 years]) were prospectively studied. Pulmonary function and CT data were acquired by pulmonologists and radiologists. Noncontrast agent-enhanced thoracic CT scans were acquired at full inspiration and expiration, and were quantitatively analyzed by using two software programs. CT parameters were set as follows: 120 kVp; 200 mAs; rotation time, 0.5 second; pitch, 1.1; section thickness, 0.75 mm; and reconstruction kernels, b31f and b70f. Gas trapping obtained by difference of inspiratory and expiratory CT density thresholds (percentage area with CT attenuation values less than -950 HU at inspiration and percentage area with CT attenuation values less than -856 HU at expiration) was compared with that obtained by coregistration analysis. A logistic regression model on the basis of anthropometric and functional data was cross-validated and trained to classify patients with COPD according to the relative contribution of emphysema to total gas trapping, as assessed at CT. Results Gas trapping obtained by difference of inspiratory and expiratory CT density thresholds was highly correlated (r = 0.99) with that obtained by coregistration analysis. Four groups of patients were distinguished according to the prevalent CT subtype: prevalent emphysematous gas trapping, prevalent functional gas trapping, mixed severe, and mixed mild. The predictive model included predicted forced expiratory volume in 1 second/vital capacity, percentage of predicted forced expiratory volume in 1 second, percentage of diffusing capacity for carbon monoxide, and body mass index as emphysema regressors at CT, with 81% overall accuracy in classifying patients according to its extent. Conclusion The relative contribution of emphysematous and nonemphysematous gas trapping obtained by coregistration of inspiratory and expiratory CT scanning can be determined accurately by difference of CT inspiratory and expiratory density thresholds. CT extent of emphysema can be predicted with accuracy suitable for clinical purposes by pulmonary function data and body mass index. ^© RSNA, 2018 Online supplemental material is available for this article.

Lung densitometry: why, how and when

Lung densitometry assesses with computed tomography (CT) the X-ray attenuation of the pulmonary tissue which reflects both the degree of inflation and the structural lung abnormalities implying decreased attenuation, as in emphysema and cystic diseases, or increased attenuation, as in fibrosis. Five reasons justify replacement with lung densitometry of semi-quantitative visual scales used to measure extent and severity of diffuse lung diseases: (I) improved reproducibility; (II) complete vs. discrete assessment of the lung tissue; (III) shorter computation times; (IV) better correlation with pathology quantification of pulmonary emphysema; (V) better or equal correlation with pulmonary function tests (PFT). Commercially and open platform software are available for lung densitometry. It requires attention to technical and methodological issues including CT scanner calibration, radiation dose, and selection of thickness and filter to be applied to sections reconstructed from whole-lung CT acquisition. Critical is also the lung volume reached by the subject at scanning that can be measured in post-processing and represent valuable information per se. The measurements of lung density include mean and standard deviation, relative area (RA) at -970, -960 or -950 Hounsfield units (HU) and 1st and 15th percentile for emphysema in inspiratory scans, and RA at -856 HU for air trapping in expiratory scans. Kurtosis and skewness are used for evaluating pulmonary fibrosis in inspiratory scans. The main indication for lung densitometry is assessment of emphysema component in the single patient with chronic obstructive pulmonary diseases (COPD). Additional emerging applications include the evaluation of air trapping in COPD patients and in subjects at risk of emphysema and the staging in patients with lymphangioleiomyomatosis (LAM) and with pulmonary fibrosis. It has also been applied to assess prevalence of smoking-related emphysema and to monitor progression of smoking-related emphysema, alpha1 antitrypsin deficiency emphysema, and pulmonary fibrosis. Finally, it is recommended as end-point in pharmacological trials of emphysema and lung fibrosis.

Glottis Closure Influences Tracheal Size Changes in Inspiratory and Expiratory CT in Patients with COPD

RATIONALE AND OBJECTIVES

The opened or closed status of the glottis might influence tracheal size changes in inspiratory and expiratory computed tomography (CT) scans. We investigated if the glottis status makes the tracheal collapse differently correlate with lung volume difference between inspiratory and expiratory CT scans.

MATERIALS AND METHODS

Forty patients with chronic obstructive pulmonary disease whose glottis was included in the acquired scanned volume for lung CT were divided into two groups: 16 patients with the glottis closed in both inspiratory and expiratory CT, and 24 patients with the glottis open in at least one CT acquisition. Lung inspiratory (Vinsp) and expiratory (Vexp) volumes were automatically computed and lung ΔV was calculated using the following formula: (Vinsp - Vexp)/Vinsp × 100. Two radiologists manually measured the anteroposterior diameter and cross-sectional area of the trachea 1 cm above the aortic arch and 1 cm above the carina. Tracheal collapse was then calculated and correlated with lung ΔV.

RESULTS

In the 40 patients, the correlations between tracheal Δanteroposterior diameter and Δcross-sectional area at each level and lung ΔV ranged between 0.68 and 0.74 (ρ) at Spearman rank correlation test. However, in the closed glottis group, the correlations were higher for all measures at the two levels (ρ range: 0.84-0.90), whereas in the open glottis group, correlations were low and not statistically significant (ρ range: 0.29-0.34) at the upper level, and moderate at the lower level (ρ range: 0.51-0.55).

CONCLUSIONS

A closed or open glottis influences the tracheal size change in inspiratory and expiratory CT scans. With closed glottis, the tracheal collapse shows a stronger correlation with the lung volume difference between inspiratory and expiratory CT scans.

Do COPD subtypes really exist? COPD heterogeneity and clustering in 10 independent cohorts

BACKGROUND

COPD is a heterogeneous disease, but there is little consensus on specific definitions for COPD subtypes. Unsupervised clustering offers the promise of 'unbiased' data-driven assessment of COPD heterogeneity. Multiple groups have identified COPD subtypes using cluster analysis, but there has been no systematic assessment of the reproducibility of these subtypes.

OBJECTIVE

We performed clustering analyses across 10 cohorts in North America and Europe in order to assess the reproducibility of (1) correlation patterns of key COPD-related clinical characteristics and (2) clustering results.

METHODS

We studied 17 146 individuals with COPD using identical methods and common COPD-related characteristics across cohorts (FEV₁, FEV₁/FVC, FVC, body mass index, Modified Medical Research Council score, asthma and cardiovascular comorbid disease). Correlation patterns between these clinical characteristics were assessed by principal components analysis (PCA). Cluster analysis was performed using k-medoids and hierarchical clustering, and concordance of clustering solutions was quantified with normalised mutual information (NMI), a metric that ranges from 0 to 1 with higher values indicating greater concordance.

RESULTS

The reproducibility of COPD clustering subtypes across studies was modest (median NMI range 0.17-0.43). For methods that excluded individuals that did not clearly belong to any cluster, agreement was better but still suboptimal (median NMI range 0.32-0.60). Continuous representations of COPD clinical characteristics derived from PCA were much more consistent across studies.

CONCLUSIONS

Identical clustering analyses across multiple COPD cohorts showed modest reproducibility. COPD heterogeneity is better characterised by continuous disease traits coexisting in varying degrees within the same individual, rather than by mutually exclusive COPD subtypes.

Prevalence of comorbidities according to predominant phenotype and severity of chronic obstructive pulmonary disease

Background

In addition to lung involvement, several other diseases and syndromes coexist in patients with chronic obstructive pulmonary disease (COPD). Our purpose was to investigate the prevalence of idiopathic arterial hypertension (IAH), ischemic heart disease, heart failure, peripheral vascular disease (PVD), diabetes, osteoporosis, and anxious depressive syndrome in a clinical setting of COPD outpatients whose phenotypes (predominant airway disease and predominant emphysema) and severity (mild and severe diseases) were determined by clinical and functional parameters.

Methods

A total of 412 outpatients with COPD were assigned either a predominant airway disease or a predominant emphysema phenotype of mild or severe degree according to predictive models based on pulmonary functions (forced expiratory volume in 1 second/vital capacity; total lung capacity %; functional residual capacity %; and diffusing capacity of lung for carbon monoxide %) and sputum characteristics. Comorbidities were assessed by objective medical records.

Results

Eighty-four percent of patients suffered from at least one comorbidity and 75% from at least one cardiovascular comorbidity, with IAH and PVD being the most prevalent ones (62% and 28%, respectively). IAH prevailed significantly in predominant airway disease, osteoporosis prevailed significantly in predominant emphysema, and ischemic heart disease and PVD prevailed in mild COPD. All cardiovascular comorbidities prevailed significantly in predominant airway phenotype of COPD and mild COPD severity.

Conclusion

Specific comorbidities prevail in different phenotypes of COPD; this fact may be relevant to identify patients at risk for specific, phenotype-related comorbidities. The highest prevalence of comorbidities in patients with mild disease indicates that these patients should be investigated for coexisting diseases or syndromes even in the less severe, pauci-symptomatic stages of COPD. The simple method employed to phenotype and score COPD allows these results to be translated easily into daily clinical practice.

Interstitial lung disease in systemic sclerosis: where do we stand?

Interstitial lung disease (ILD) is common in systemic sclerosis (SSc) patients and despite recent advances in the treatment is, at present, the major cause of death. Today, an early diagnosis of ILD is possible, and is mandatory to improve the prognosis of the disease. Pulmonary function tests and high-resolution computed tomography remain the mainstay for the diagnosis of SSc-ILD, but there is a growing interest in lung ultrasound. Recently, the correlation between severity of fibrosis and some peripheral blood biomarkers has been described. Nonselective immunosuppressors are still the main treatment for ILD, with cyclophosphamide (CYC) most widely used to obtain remission. Novel therapies towards specific molecular and cellular targets have been suggested; in particular, rituximab (RTX) has shown promising results, but further research is needed. It is of paramount importance to define the severity of the disease and the risk of progression in order to define the need for treatment and the treatment intensity. We propose the division of the treatment strategies at our disposal to induce remission into three categories: high intensity (haematopoietic stem cell transplantation), medium intensity (CYC and RTX) and low intensity (azathioprine (AZA) and mycophenolate mofetil (MMF)). After obtaining remission, maintenance treatment with AZA or MMF should be started. In this review we explore new advances in the pathogenesis, diagnosis and treatment of SSc-ILD.

Is intrathoracic tracheal collapsibility correlated to clinical phenotypes and sex in patients with COPD?

A substantial proportion of patients with chronic obstructive pulmonary disease (COPD) develops various degree of intrathoracic tracheal collapsibility. We studied whether the magnitude of intrathoracic tracheal collapsibility could be different across clinical phenotypes and sex in COPD. Intrathoracic tracheal collapsibility measured at paired inspiratory-expiratory low dose computed tomography (CT) and its correlation with clinical, functional, and CT-densitometric data were investigated in 69 patients with COPD according to their predominant conductive airway or emphysema phenotypes and according to sex. Intrathoracic tracheal collapsibility was higher in patients with predominant conductive airway disease (n=28) and in females (n=27). Women with a predominant conductive airway phenotype (n=10) showed a significantly greater degree of collapsibility than women with predominant emphysema (28.9%±4% versus 11.6%±2%; P<0.001). Intrathoracic tracheal collapsibility was directly correlated with inspiratory-expiratory volume variation at CT and with forced expiratory volume (1 second), and inversely correlated with reduced CT lung density and functional residual capacity. Intrathoracic tracheal collapsibility was not correlated with cough and wheezing; however, intrathoracic tracheal collapsibility and clinical phenotypes of COPD are closely correlated. In patients with a predominant emphysematous phenotype, a reduced collapsibility may reflect the mechanical properties of the stiff hyperinflated emphysematous lung. The high collapsibility in patients with predominant airway disease, mild airway obstruction, and in women with this phenotype may reflect chronic airway inflammation. The lack of relationship with such symptoms as wheezing, cough, and dyspnea could indicate that intrathoracic tracheal collapsibility itself should be considered neither an abnormal feature of COPD nor a relevant clinical finding.

Chronic Obstructive Pulmonary Disease: Pulmonary Function and CT Lung Attenuation Do Not Show Linear Correlation

PURPOSE

To determine whether the relationship between pulmonary function and computed tomographic (CT) lung attenuation in chronic obstructive pulmonary disease (COPD), which is traditionally described with single univariate and multivariate statistical models, could be more accurately described with a multiple model estimation approach.

MATERIALS AND METHODS

The study was approved by the local ethics committee. All participants provided written informed consent. The prediction of the percentage area with CT attenuation values less than -950 HU at inspiration (%LAA-950insp) and less than -910 HU at expiration (%LAA-910exp) obtained with single univariate and multivariate models was compared with that obtained with a multiple model estimation approach in 132 patients with COPD.

RESULTS

At univariate analysis, %LAA-950insp and %LAA-910exp values higher than the mean value of this cohort (19.1% and 22.0%) showed better correlation with percentage of predicted diffusing capacity of lung for carbon monoxide (Dlco%) than with airflow obstruction (forced expiratory volume in 1 second [FEV1]/vital capacity [VC]). Conversely, %LAA-950insp and %LAA-910exp values lower than the mean value were correlated with FEV1/VC but not with Dlco%. Multiple model estimation performed with two multivariate regressions, each selecting the most appropriate functional variables (FEV1/VC for mild parenchymal destruction, Dlco% and functional residual capacity for severe parenchymal destruction), predicted better than single multivariate regression both %LAA-950insp (R(2) = 0.75 vs 0.46) and %LAA-910exp (R(2) = 0.83 vs 0.63).

CONCLUSION

The relationship between pulmonary function data and CT densitometric changes in COPD varies with the level of lung attenuation impairment. The nonlinear profile of this relationship is accurately predicted with a multiple model estimation approach.

COPD: maximization of bronchodilation

The most recent guidelines define COPD in a multidimensional way, nevertheless the diagnosis is still linked to the limitation of airflow, usually measured by the reduction in the FEV1/FVC ratio below 70%. However, the severity of obstruction is not directly correlated to symptoms or to invalidity determined by COPD. Thus, besides respiratory function, COPD should be evaluated based on symptoms, frequency and severity of exacerbations, patient's functional status and health related quality of life (HRQoL). Therapy is mainly aimed at increasing exercise tolerance and reducing dyspnea, with improvement of daily activities and HRQoL. This can be accomplished by a drug-induced reduction of pulmonary hyperinflation and exacerbations frequency and severity. All guidelines recommend bronchodilators as baseline therapy for all stages of COPD, and long-acting inhaled bronchodilators, both beta-2 agonist (LABA) and antimuscarinic (LAMA) drugs, are the most effective in regular treatment in the clinically stable phase. The effectiveness of bronchodilators should be evaluated in terms of functional (relief of bronchial obstruction and pulmonary hyperinflation), symptomatic (exercise tolerance and HRQoL), and clinical improvement (reduction in number or severity of exacerbations), while the absence of a spirometric response is not a reason for interrupting treatment, if there is subjective improvement in symptoms. Because LABA and LAMA act via different mechanisms of action, when administered in combination they can exert additional effects, thus optimizing (i.e. maximizing) sustained bronchodilation in COPD patients with severe airflow limitation, who cannot benefit (or can get only partial benefit) by therapy with a single bronchodilator. Recently, a fixed combination of ultra LABA/LAMA (indacaterol/glycopyrronium) has shown that it is possible to get a stable and persistent bronchodilation, which can help in avoiding undesirable fluctuations of bronchial calibre.

COPD: maximization of bronchodilation

The most recent guidelines define COPD in a multidimensional way, nevertheless the diagnosis is still linked to the limitation of airflow, usually measured by the reduction in the FEV1/FVC ratio below 70%. However, the severity of obstruction is not directly correlated to symptoms or to invalidity determined by COPD. Thus, besides respiratory function, COPD should be evaluated based on symptoms, frequency and severity of exacerbations, patient’s functional status and health related quality of life (HRQoL). Therapy is mainly aimed at increasing exercise tolerance and reducing dyspnea, with improvement of daily activities and HRQoL. This can be accomplished by a drug-induced reduction of pulmonary hyperinflation and exacerbations frequency and severity. All guidelines recommend bronchodilators as baseline therapy for all stages of COPD, and long-acting inhaled bronchodilators, both beta-2 agonist (LABA) and antimuscarinic (LAMA) drugs, are the most effective in regular treatment in the clinically stable phase. The effectiveness of bronchodilators should be evaluated in terms of functional (relief of bronchial obstruction and pulmonary hyperinflation), symptomatic (exercise tolerance and HRQoL), and clinical improvement (reduction in number or severity of exacerbations), while the absence of a spirometric response is not a reason for interrupting treatment, if there is subjective improvement in symptoms. Because LABA and LAMA act via different mechanisms of action, when administered in combination they can exert additional effects, thus optimizing (i.e. maximizing) sustained bronchodilation in COPD patients with severe airflow limitation, who cannot benefit (or can get only partial benefit) by therapy with a single bronchodilator. Recently, a fixed combination of ultra LABA/LAMA (indacaterol/glycopyrronium) has shown that it is possible to get a stable and persistent bronchodilation, which can help in avoiding undesirable fluctuations of bronchial calibre.

Asthma control in severe asthmatics under treatment with omalizumab: a cross-sectional observational study in Italy

Few data are available on the proportion of asthmatics achieving a good asthma control (according GINA guidelines) and on the level of airway inflammation during omalizumab treatment. The aim of this cross-sectional national observational study was to assess the level of control (according to GINA guidelines) achieved in a group of asthmatics on omalizumab treatment, and to characterize the factors that influence the lack of control. We studied 306 asthmatics under omalizumab treatment for a median of 32 months (range 4-120). The level of control according to GINA was good in 25.2%, partial in 47.1% and poor in 24.5% of patients (data were missing for the remaining 3.2%). Comparison between poorly controlled and partially or well controlled asthmatics showed a statistically significant higher prevalence of some comorbidities in the first group, namely obesity, gastro-oesophageal reflux disease (GORD), aspirin intolerance and mental disorders (all p < 0.001). Similarly, asthmatics with at least one exacerbation in the last year showed a significantly higher prevalence of obesity, chronic rhinosinusitis, nasal polyps, GORD, and aspirin intolerance (all p < 0.05) than patients without exacerbations. When we selected patients without relevant comorbidities (upper airways disease, GORD, obesity, aspirin intolerance) and not currently smoking (N = 73), the percentage of well or partially controlled asthmatics was significantly higher than in patients with comorbidities (84.9% vs 71.1%, p = 0.02); the rate of asthmatics without exacerbations in the last year was also higher (73.6% vs 51.1%, p = 0.001). During omalizumab treatment, a high percentage of asthmatics obtain a good or partial control of asthma. Comorbidities are associated with the lack of asthma control and persistence of exacerbations.

Different respiratory behaviors disclosed by induced bronchoconstriction in mild asthma patients

Respiratory responses to bronchoconstriction in asthma have been partially assessed and their significance is unclear. In 44 mild asthma patients we investigated respiratory responses during increasing levels of methacholine-induced bronchoconstriction. Inspiratory muscle activity, tidal volume, inspiratory and expiratory times were continuously monitored; breathing discomfort was rated. Mean inspiratory flow, respiratory frequency and ventilation were calculated. Lung function was assessed prior to and at maximum bronchoconstriction. Bronchoconstriction "dose-dependently" increased inspiratory muscle activity and breathing discomfort (P<0.01). In 37 patients (84.1%), the increase in inspiratory muscle activity was associated with increases in mean inspiratory flow and ventilation (P<0.01) because of selective rises in breathing depth (volume responders), or rate (frequency responders) or both (dual responders). In seven patients (15.9%) ventilation was unchanged. Individual respiratory responses were reproducible. With bronchoconstriction, frequency responders displayed greater hyperinflation and stronger breathing discomfort than volume responders (P<0.01). Analysis of the responses to induced bronchoconstriction disclosed distinctive and reproducible respiratory adjustments that may identify functionally different asthma subpopulations.

Whole-lung volume and density in spirometrically-gated inspiratory and expiratory CT in systemic sclerosis: correlation with static volumes at pulmonary function tests

BACKGROUND

Spiral low-dose computed tomography (LDCT) permits to measure whole-lung volume and density in a single breath-hold.

OBJECTIVE

To evaluate the agreement between static lung volumes measured with LDCT and pulmonary function test (PFT) and the correlation between the LDCT volumes and lung density in restrictive lung disease.

DESIGN

Patients with Systemic Sclerosis (SSc) with (n = 24) and without (n = 16) pulmonary involvement on sequential thin-section CT and patients with chronic obstructive pulmonary disease (COPD)(n = 29) underwent spirometrically-gated LDCT at 90% and 10% of vital capacity to measure inspiratory and expiratory lung volumes and mean lung attenuation (MLA). Total lung capacity and residual volume were measured the same day of CT.

RESULTS

Inspiratory [95% limits of agreement (95% LoA)--43.8% and 39.2%] and expiratory (95% LoA -45.8% and 37.1%) lung volumes measured on LDCT and PFT showed poor agreement in SSc patients with pulmonary involvement, whereas they were in substantial agreement (inspiratory 95% LoA -14.1% and 16.1%; expiratory 95% LoA -13.5% and 23%) in SSc patients without pulmonary involvement and in inspiratory scans only (95% LoA -23.1% and 20.9%) of COPD patients. Inspiratory and expiratory LDCT volumes, MLA and their deltas differentiated both SSc patients with or without pulmonary involvement from COPD patients. LDCT lung volumes and density were not correlated in SSc patients with pulmonary involvement, whereas they did correlate in SSc without pulmonary involvement and in COPD patients.

CONCLUSIONS

In restrictive lung disease due to SSc there is poor agreement between static lung volumes measured using LDCT and PFT and the relationship between volume and density values on CT is altered.

Pulmonary function and sputum characteristics predict computed tomography phenotype and severity of COPD

Airway obstruction and parenchymal destruction underlie phenotype and severity in chronic obstructive pulmonary disease (COPD). We aimed to predict, by clinical and pulmonary function data, the predominant type and severity of pathological changes quantitatively assessed by computed tomography (CT). Airway wall thickness (AWT-Pi10) and percentage of lung area with X-ray attenuation values <-950 HU (%LAA-950) were measured in 100 (learning set) out of 473 COPD outpatients undergoing clinical and functional evaluation. Original CT measurements were translated by principal component analysis onto a plane with the novel coordinates CT1 and CT2, depending on the difference (prevalent mechanism of airflow limitation) and on the sum (severity) of AWT-Pi10 and %LAA-950, respectively. CT1 and CT2, estimated in the learning set by cross-validated models of clinical and functional variables, were used to classify 373 patients in the testing set. A model based on diffusing capacity of the lung for carbon monoxide, total lung capacity and purulent sputum predicted CT1 (r = 0.64; p<0.01). A model based on forced expiratory volume in 1 s/vital capacity, functional residual capacity and purulent sputum predicted CT2 (r = 0.77; p<0.01). Classification of patients in the testing set obtained by model-predicted CT1 and CT2 reflected, according to correlations with clinical and functional variables, both COPD phenotype and severity. Multivariate models based on pulmonary function variables and sputum purulence classify patients according to overall severity and predominant phenotype of COPD as assessed quantitatively by CT.

BODE-index, modified BODE-index and ADO-score in chronic obstructive pulmonary disease: relationship with COPD phenotypes and CT lung density changes

COPD is a heterogeneous disorder whose assessment is going to be increasingly multidimensional. Grading systems such as BODE (Body-Mass Index, Obstruction, Dyspnea, Exercise), mBODE (BODE modified in grading of walked distance), ADO (Age, Dyspnea, Obstruction) are proposed to assess COPD severity and outcome. Computed tomography (CT) is deemed to reflect COPD lung pathologic changes. We studied the relationship of multidimensional grading systems (MGS) with clinically determined COPD phenotypes and CT lung density. Seventy-two patients underwent clinical and chest x-ray evaluation, pulmonary function tests (PFT), 6-minute walking test (6MWT) to derive: predominant COPD clinical phenotype, BODE, mBODE, ADO. Inspiratory and expiratory CT was performed to calculate mean lung attenuation (MLA), relative area with density below-950 HU at inspiration (RAI(-950)), and below -910 HU at expiration (RAE(-910)). MGS, PFT, and CT data were compared between bronchial versus emphysematous COPD phenotype. MGS were correlated with CT data. The prediction of CT density by means of MGS was investigated by direct and stepwise multivariate regression. MGS did not differ in clinically determined COPD phenotypes. BODE was more closely related and better predicted CT findings than mBODE and ADO; the better predictive model was obtained for CT expiratory data; stepwise regression models of CT data did not include 6MWT distance; the dyspnea score MRC was included only to predict RA-950 and RA-910 which quantify emphysema extent. BODE reflect COPD severity better than other MGS, but not its clinical heterogeneity. 6MWT does not significantly increase BODE predictivity of CT lung density changes.

Low agreement of visual rating for detailed quantification of pulmonary emphysema in whole-lung CT

BACKGROUND

Multidetector spiral computed tomography (CT) has opened the possibility of quantitative evaluation of emphysema extent in the whole lung. Visual assessment can be used for such a purpose, but its reproducibility has not been established.

PURPOSE

To assess agreement of detailed assessment of pulmonary emphysema on whole-lung CT using a visual scale.

MATERIAL AND METHODS

Thirty patients with chronic obstructive pulmonary disease underwent whole-lung inspiratory CT. Four chest radiologists rated the same 22 ± 2 thin sections using a visual scale which defines a range of emphysema extent between 0 and 100. Two of them repeated the rating two months later. Inter- and intra-operator agreement was evaluated with the Bland and Altman method. In addition, the percentage of emphysema at -950 Hounsfield units in the whole lung was determined using fully automated commercially available software for 3D densitometry.

RESULTS

In three of six operator pairs and in one of two intra-operator pairs the Kendall τ test showed a significant correlation between the difference and the average magnitude of visual scores. Among different operators the half-width of 95% limits of agreement (95% LoA) was wide ranging between a score of 14.2-27.7 for an average visual score of 20 and between 18.5-36.8 for an average visual score of 80. Within the same operator the half-width of 95% LoA ranged between a score of 10.9-21.0 for an average visual score of 20 and between 25.1-30.1 for an average visual score of 80. The visual scores of the four radiologists were correlated with the results of densitometry (P < 0.001; r = 0.65-0.81).

CONCLUSION

The inter- and intra-operator agreement of detailed assessment of emphysema in the whole lung using a visual scale is low and decreases with increasing emphysema extent.

Italian real-life experience of omalizumab

Omalizumab is a humanized murine monoclonal antibody directed toward a portion of the IgE indicated in Europe for the treatment of severe persistent allergic asthma, inadequately controlled despite high-dose of ICS (mean BDP equivalent dose of inhaled corticosteroid 2224.68microg/die) in association with long-acting beta(2) agonists. Our aim was to describe the experience, efficacy and safety in a cohort of Italian patients treated with omalizumab in a real-life clinical setting. One hundred and forty two patients from 13 Italian Centers were observed and analysed. The dosage of omalizumab was established according to the labelling indication, with a median dose of IgE of 297.38IU/ml or kU/l. During the previous year, all patients experienced frequent exacerbations (mean=4.87), emergency visits (mean=4.45) and hospitalisation (mean=1.53). Following treatment with omalizumab, the annual rate of exacerbations, emergency visits and hospitalisation decreased by 79%, 88% and 95%, respectively. The proportion of patients without exacerbation, not needing emergency visits and hospitalization increased by 610%, 154% and 28%, respectively. The response to omalizumab measured with the GETE (global evaluation of treatment effectiveness) scale rated as good to excellent in 77% of patients. Overall, 9.6% (n=9) of the patients experienced one single adverse effect. Only one patient reported a serious adverse event (local reaction at the site of injection) leading to interruption of treatment. The observed reduction of asthma-related events in particularly poorly controlled patients in this Italian real-life setting is consistent with the results of other observational studies.

Non-contact detection of breathing using a microwave sensor

In this paper the use of a continuous-wave microwave sensor as a non-contact tool for quantitative measurement of respiratory tidal volume has been evaluated by experimentation in seventeen healthy volunteers. The sensor working principle is reported and several causes that can affect its response are analyzed. A suitable data processing has been devised able to reject the majority of breath measurements taken under non suitable conditions. Furthermore, a relationship between microwave sensor measurements and volume inspired and expired at quiet breathing (tidal volume) has been found.

Whole-lung densitometry versus visual assessment of emphysema

We compared whole-lung densitometry with visual evaluation of pulmonary emphysema. Thirty patients with chronic obstructive pulmonary disease underwent multi-detector CT (150 mAs and 0.75 collimation) with double reconstruction: thick (5-mm) slices with smooth filter for whole-lung densitometry and thin (1 mm) slices with sharp filter for visual assessment (one of every ten slices). Densitometry and visual assessment were performed by three operators each, and the time required for assessment, the inter-observer agreement and the correlation with the results of the diffusion capacity of carbon monoxide (DL(CO)) in the same patients were computed. The average time for densitometry (8.49 +/- 0.13 min) was significantly longer (p < 0.0001) than that for visual evaluation (5.14 +/- 0.11 min). However, the inter-operator agreement ranged between "moderate" to "almost perfect" for densitometry (kappa range 0.58-0.87) and "slight" for visual (kappa = 0.20) assessment. The correlation coefficients of DL(CO) with relative area at -960 and -970 Hounsfield units (HU) (both r = -0.66) and of the first percentile point of lung density (r = 0.66) were slightly stronger than that of the visual score (r = -0.62). Densitometry should be preferred to visual assessment because it enables a more reproducible evaluation of the extent of pulmonary emphysema, which can be carried out on the entire lung in a reasonable amount of time.

Identification of a predominant COPD phenotype in clinical practice

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation caused by small airways increased resistance and/or terminal airspaces emphysematous destruction. Spirometric detection of not fully reversible airflow limitation unifies under the acronym COPD, a spectrum of heterogeneous conditions, whose clinical presentations may be substantially different. In a cross-sectional study we aimed to ascertain whether COPD phenotypes reflecting different mechanisms of airflow limitation could be clinically identified.

METHODS

Multidimensional scaling was used to visualize as a single point in a two-dimension space the multidimensional variables derived from each of 322 COPD patients (derivation set) by clinical, functional, and chest radiographic evaluation. Cluster analysis assigned then a cluster membership to each patient data point. Finally, using cluster membership as dependent variable and all data acquired as independent variables, we developed multivariate models to prospectively classify another group of 93 COPD patients (validation set) in whom high-resolution computerized tomography (HRCT) density parameters were measured.

RESULTS

A multivariate model based on nine variables acquired from the derivation set by history (sputum characteristics), physical examination (adventitious sounds, hyperresonance), FEV1/VC, and chest radiography (increased vascular markings, bronchial wall thickening, increased lung volume, reduced lung density) partitioned the validation set into two groups whose clinical, functional, chest radiographic, and HRCT characteristics corresponded to either an airways obstructive or a parenchymal destructive COPD phenotype.

CONCLUSION

Patients with COPD can be assigned a clinical phenotype reflecting the prevalent mechanism of airflow limitation. The standardized identification of the predominant phenotype may permit to clinically characterize COPD beyond its unifying spirometric definition.

Chronic effort dyspnea explained by lung function tests and by HRCT and CRX radiographic patterns in COPD: a post-hoc analysis in 51 patients

This paper is a post-hoc analysis of a previous study performed to investigate the relationship between computerized tomography (CT) and lung function in 51 outpatients with mild-to-moderate COPD. We studied whether changes in lung function and radiographic patterns may help to explain dyspnea, the most disturbing symptom in patients with COPD. The Medical Research Council (MRC) dyspnea scale shows, by univariate analysis, a similar strength of association to CT expiratory lung density and to DL(CO), a functional index of lung parenchymal loss. The MRC dyspnea scale shows a somewhat less strength of association with a small vertical heart on plain chest films. In multivariate analysis, the model with the strongest association to the MRC dyspnea scale (r = 0.76, p < 0.0001) contains 4 explanatory variables (DL(CO), FRC, PaCO(2), and radiographic pattern of pulmonary hypertension). We suggest that diffusing capacity reflects the emphysematous component of hyperinflation, associated by definition with destruction of terminal airspace walls, as distinct from the air trapping component, which is ascribed to airway obstruction and associated with FRC. PaCO(2) mainly reflects the ventilatory components, i.e., ventilatory drive and ventilatory constraints, of pulmonary gas exchange in COPD, while radiographic pattern of pulmonary hypertension likely reflects hypoxic vascular changes, which depend mainly on ventilation/perfusion mismatch and give rise to pulmonary arterial hypertension that may contribute per se to dyspnea. In conclusion, our analysis points out that chronic effort dyspnea variance may account for up to 58% (r(2) = 0.58) by lung function tests and radiographic patterns. Thus, about 42% of the MRC dyspnea variance remains unexplained by this model. On the other hand, dyspnea ascertainment is dependent on subjective behavior and evaluation and in tests is influenced by individual performance and perception. For example in the 6-minute walk test, a similar or higher proportion (60%) of the overall variance is unexplained.

Agreement between two methods for assessing bioequivalence of inhaled salbutamol

For inhaled medications, bioequivalence testing is becoming increasingly important owing to the availability of many inhalation devices. We evaluated agreement between the Finney bioassay and the Emax model in the assessment of bioequivalence of salbutamol administered via a metered-dose inhaler with a spacer (pMDI+ Volumatic) or via a dry-powder inhaler (Diskus) in asthmatic patients with methacholine-induced bronchoconstriction. Eighteen patients inhaled methacholine until FEV 1 decreased by approximately 35% of control. Following inhalation of placebo, 200 and 400 mcg salbutamol through the pMDI+ Volumatic or the Diskus, changes in FEV 1 were repeatedly measured over a 60-min observation period. Bioequivalence of salbutamol administered via the two inhalation devices was assessed by calculating the relative potency of each device by using the Finney 2-by-2 parallel regression analysis and the non-linear, Emax model. Agreement between these methods in calculating relative potency was evaluated by using the Bland-Altman method. After salbutamol FEV 1 values were similar irrespective of the device employed, and greater (P<0.01) than those after placebo. However, assessment of relative potencies obtained with both the Finney (1.97, 90% CI 1.62-2.32) and the Emax (2.25, 90% CI 1.90-2.60) methods revealed that twice the salbutamol dose was needed to reverse methacholine-induced bronchoconstriction when the drug was inhaled via the Diskus than via the pMDI+ Volumatic. The mean difference in relative potency (-0.28, 90% CI -0.001 to -0.56) calculated with both methods did not significantly differ from zero, and none of the individual differences exceeded the limits of agreement. The Finney and the Emax methods provide comparable results in the evaluation of bioequivalence of different salbutamol formulations. The pMDI+ Volumatic is twice as efficient as the Diskus in lung delivery of salbutamol in asthma patients.

Lung CT densitometry in systemic sclerosis: correlation with lung function, exercise testing, and quality of life

BACKGROUND

To ascertain if analysis of lung density histograms in thin-section CT was more reproducible than visual assessment of lung changes in systemic sclerosis (SSc), and if such density histogram parameters as mean lung attenuation (MLA), skewness, and kurtosis could more closely reflect pulmonary function as well as exercise and quality of life impairment.

METHODS

The intraoperator and interoperator reproducibility of visual and densitometric lung CT analysis in 48 SSc patients examined with CT were evaluated by means of weighted kappa statistics. Univariate and multivariate regression analyses were applied to evaluate the relationship of visual and densitometric CT measurements with functional parameters including functional residual capacity (FRC), FVC, FEV(1), diffusion capacity of the lung for carbon monoxide (Dlco), 6-min walking testing (6MWT), and health-related quality of life questionnaire (QLQ) parameters.

RESULTS

The intraoperator and interoperator reproducibility of MLA (intraobserver weighted kappa = 0.97; interobserver weighted kappa = 0.96), skewness (intraobserver weighted kappa = 0.89; interobserver weighted kappa = 0.88), and kurtosis (intraobserver weighted kappa = 0.89; interobserver weighted kappa = 0.88) were higher than those of visual assessment (intraobserver weighted kappa = 0.71; interobserver weighted kappa = 0.69). In univariate analysis, only densitometric measurements were correlated with some exercise and QLQ parameters. In multivariate analysis, MLA (square regression coefficient corrected [R(2)c] = 0.70), skewness (R(2)c = 0.78), and kurtosis (R(2)c = 0.77) were predicted by FRC, FVC, Dlco, 6MWT, and QLQ parameters, while visual assessment was associated only with FRC and FVC (R(2)c = 0.40).

CONCLUSIONS

In SSc, densitometric analysis is more reproducible than visual assessment of lung changes in thin-section CT and more closely correlated to pulmonary function testing, 6MWT, and QLQ. Density histogram parameters may be useful for cross-sectional and longitudinal studies of lung involvement in SSc.

Obstructive sleep apnea syndrome as a complication after tracheal surgery

We describe a case of obstructive sleep apnea syndrome that occurred after tracheal surgery. The patient refused a tracheal stent placement and any surgical procedure aimed at stabilizing the tracheal walls. She was treated with a continuous positive airway pressure.

Thin-Section and Low-Dose Volumetric Computed Tomographic Densitometry of the Lung in Systemic Sclerosis

OBJECTIVE

To correlate lung density measurements with the results of visual assessment of thin-section computed tomography (CT) and of pulmonary function tests (PFT) in Systemic Sclerosis (SSc).

METHODS

Thirty-nine SSc patients underwent sequential thin-section CT and spiral low-dose whole-lung acquisitions. The thin-section CT scans were evaluated with a dedicated visual scale. Mean lung density, skewness, and kurtosis were calculated from the lung density histogram. In addition from the spiral low-dose acquisition, the lung volume was computed. The visual score, the densitometric parameters, and the lung volume were correlated with the PFT.

RESULTS

Mean lung density, skewness, and kurtosis computed from thin-section (R = 0,66; R = -0,74; R = -0,75) and low-dose volumetric (R = 0,72; R = -0,71; R = -0,71) CT and the lung volume (R = -0.54) correlated with the visual score. Densitometric values and lung volume consistently better correlated with PFT than the visual score.

CONCLUSIONS

In SSc the histogram results are more closely correlated to PFT than the visual score. The low-dose spiral CT seems ideal for longitudinal studies.

Spirometrically gated high-resolution CT findings in COPD: lung attenuation vs lung function and dyspnea severity

STUDY OBJECTIVES

The aim of this study was to investigate the relationship between high-resolution CT (HRCT) lung attenuation measurements, acquired under spirometric control of inspiratory and expiratory lung volume, and pulmonary dysfunction as well as dyspnea severity in patients with COPD.

PATIENTS AND DESIGN

In 51 patients with COPD, we compared by linear regression, univariate and multivariate logistic regression airflow limitation (FEV(1)/vital capacity [VC]), hyperinflation (percentage of predicted residual volume [RV%]), parenchymal loss (percentage of predicted diffusing capacity of the lung for carbon monoxide [Dlco%]), and Medical Research Council (MRC) dyspnea scale with relative area with attenuation values < - 950 HU at 90% of VC [RAI(950)] and < - 910 HU at 10% of VC, respectively, and with mean lung attenuation measured at the same levels of VC (mean CT lung density at 10% of VC, and mean CT lung density at 90% of VC [MeanCTEXP]).

RESULTS

All HRCT attenuation measurements were significantly related with functional abnormalities and dyspnea severity. In multivariate logistic models, with 1 indicating worse changes in dichotomous outcome variables, MeanCTEXP independently predicted FEV(1)/VC (odds ratio [OR], 0.24; 95% confidence interval [CI], 0.11 to 0.56), RV% (OR, 0.57; 95% CI, 0.42 to 0.77), and MRC dyspnea scale (OR, 0.63; 95% CI, 0.48 to 0.82), while RAI(950) independently predicted Dlco% (OR, 1.90; 95% CI, 1.37 to 2.65).

CONCLUSIONS

Spirometrically gated measurements of HRCT lung attenuation reflect differently functional changes and dyspnea perception in COPD. Inspiratory measurements assess the extent of emphysematous tissue loss, and expiratory measurements may reflect airflow limitation and lung hyperinflation with attendant dyspnea perception. Pulmonary dysfunction in COPD cannot be assessed by a single modality of lung attenuation measurement.

Chronic obstructive pulmonary disease: thin-section CT measurement of airway wall thickness and lung attenuation

PURPOSE

To prospectively evaluate airway wall thickness and lung attenuation at spirometrically gated thin-section computed tomography (CT) in patients with chronic obstructive pulmonary disease (COPD) and to correlate gated CT findings with pulmonary function test (PFT) results.

MATERIALS AND METHODS

The ethical committee approved the study, and all patients gave informed consent. Forty-two consecutive patients with COPD (20 with and 22 without chronic bronchitis [CB]) underwent gated thin-section CT and PFTs on the same day. The percentage wall area (PWA) and the thickness-to-diameter ratio (TDR) for all depicted bronchi that were round and larger than 2 mm in diameter, the mean lung attenuation (MLA), and the pixel index (PI) at -950 HU were determined. The reproducibility of the airway measurements was preliminarily tested by performing a five-trial examination in a patient with COPD and in a control patient. Differences in airway and lung attenuation measurements between the patients with and those without CB were evaluated at Mann-Whitney U testing. Simple and multiple regression analyses were used to assess the correlation between thin-section CT and PFT measurements.

RESULTS

The mean intraoperator coefficient of variation for airway measurements was 7.8% (range, 3.8%-13.4%). An average of nine bronchi per patient were assessed. Patients with CB had significantly higher PWAs, TDRs, and MLAs and significantly lower PIs than patients without CB (P < .05 for all values). The combination of PWA, TDR, and PWA normalized to body weight correlated significantly (P < .05) with the forced expiratory volume in 1 second-to-slow vital capacity ratio and the diffusing capacity of the lung for carbon monoxide in patients with but not in patients without CB. PFT results correlated better with MLA and PI in patients without CB.

CONCLUSION

Bronchial wall measurements differ between patients who have COPD with CB and those who have COPD without CB. The correlation between airway dimensions and indexes of airway obstruction in patients with COPD and CB indicates that the bronchial tree is the site of anatomic-functional alterations in this patient group.

Spirometric-Gated Computed Tomography Quantitative Evaluation of Lung Emphysema in Chronic Obstructive Pulmonary Disease

OBJECTIVE

To compare the quantitative assessment of pulmonary emphysema with spirometric-gated computed tomography (gated CT) using 3 different acquisition techniques and to determine if low-current spiral CT could be used effectively to quantitate emphysema.

METHODS

Eleven patients with chronic obstructive pulmonary disease (COPD) underwent gated CT and pulmonary function tests (PFTs). Spiral whole-lung 10-mm collimation acquisitions at standard (146 mAs) and low (43 mAs) current and sequential 3-slice 1-mm collimation high-resolution computed tomography (HRCT) acquisitions at standard current were obtained at 90% of the patient's vital capacity. The mean lung density (MLD) and the pixel index (PI) derived from the 3 data sets were compared using one-way analysis of variance and correlated with PFTs using linear regression. Moreover, the radiation dose associated with each technique was measured.

RESULTS

The MLDs were not significantly different. The PIs calculated from the standard- and low-current spiral acquisitions were similar, and both were significantly different from that of HRCT. The MLDs correlated with the PFTs in standard-current spiral and HRCT but not in low-current spiral acquisitions, whereas the PIs correlated with the PFTs in all 3 techniques. High-resolution computed tomography implied the lowest dose (0.08 mSv) compared with low-current (1.2 mSv) and standard-current (4 mSv) spiral techniques.

CONCLUSIONS

Low- and standard-dose spiral CT provides similar lung density data in COPD. The combination of low-dose whole-lung spiral CT and 3-slice HRCT represents the best compromise between the amount of information provided and radiation exposure to the patient and could be substituted for standard-dose spiral CT for quantitative evaluation of COPD.

Comparison of spirometric-gated and -ungated HRCT in COPD

PURPOSE

The purpose of this work was to evaluate feasibility of spirometric-gated high-resolution computed tomography (HRCT) in patients with chronic obstructive pulmonary disease (COPD) and to compare the lung density CT measurements obtained with and without spirometric control of lung volume.

METHOD

Twenty-nine patients with COPD underwent pulmonary function tests and spirometric-gated (3 slices at 10% and 90% of vital capacity) and -ungated (12 slices at maximum expiration and inspiration) HRCT in the same day. Four lung density measurements (inspiratory pixel index, expiratory pixel index, inspiratory and expiratory mean lung density) derived from gated and ungated acquisitions were compared using the nonparametric Wilcoxon test, the line of equality, and the Bland and Altman test.

RESULTS

The vital capacity measured at pulmonary function tests and on the CT table showed a substantial agreement. All but one patient completed the gated and ungated examination, but only 8 (28%) of 28 patients reached the expiratory and inspiratory gating level for CT acquisitions at the first attempt. Only the inspiratory mean lung density derived from the 3 gated and 12 ungated slices showed borderline agreement. Other CT measurements, and notably all those from the 3 gated and ungated scans, acquired at the same anatomic level, did not agree.

CONCLUSIONS

Although the procedure can be difficult for individual patients, spirometric gating significantly influences the lung density CT measurements and might improve standardization of CT evaluation of COPD.

Fog-induced respiratory responses are attenuated by nedocromil sodium in humans

Fog inhalation induces cough and bronchoconstriction in patients with asthma, but only cough in normal subjects; whether it also influences the pattern of breathing is unclear. Nedocromil sodium (NCS) inhibits the cough response to inhalation of several pharmacological agents but its effects on fog-induced cough and changes in the pattern of breathing are unknown. We evaluated the effects of no drug, placebo, and 4- and 8-mg NCS administration on the cough threshold and changes in the pattern of breathing during fog inhalation in 14 healthy subjects. Measurements of tidal volume (VT), duration of inspiratory and expiratory times (TI and TE, respectively), total duration of the respiratory cycle (TT), mean inspiratory flow (VT/TI), duty cycle (TI/TT), respiratory frequency (f, 60/TT), and inspiratory minute ventilation (V I) were obtained by inductive plethysmography. Median cough threshold values were unaffected by placebo, but were increased (p < 0.01) by both NCS doses. In no-drug and placebo trials, inhalation of the threshold fog concentration caused increases in both VT/TI and V I (p always < 0.05) due to selective increases (p < 0.01) in VT. These changes were markedly attenuated by both NCS doses administration. Thus, fog induces coughing and increases in VT, VT/ TI, and V I in healthy subjects; NCS possesses antitussive effects and attenuates fog-induced changes in the pattern of breathing, possibly through inhibition of rapidly adapting "irritant" receptors.