Impact of reduction in antifibrotic treatment on mortality in idiopathic pulmonary fibrosis.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a severe interstitial lung disease for which two effective antifibrotics, nintedanib and pirfenidone, are available. However, many patients receive a reduced dosage or pause treatment due to side effects although the impact of antifibrotic treatment reduction is uncertain. METHODS: We retrospectively investigated the impact of antifibrotic treatment reduction on death in a large real-life IPF cohort. The primary endpoint of the analyses was time until death by any cause. Five patient groups were defined based on treatment intensity (full, reduced or no treatment) and the antifibrotic drug type (pirfenidone or nintedanib). Between group survival was compared using Cox proportional hazards analysis adjusted for age, sex, smoking status, and lung function at baseline. RESULTS: 375 patients from the Danish PFBIO-cohort were followed from April 2016 until November 2021 with a median follow-up time of 1.84 years. Of patients receiving nintedanib and pirfenidone, 80.19% and 67.42% had reduced treatment, respectively, when considering the entire follow-up period. Treatment with nintedanib and pirfenidone was associated with improved survival compared to no antifibrotic treatment independent of treatment intensity (nintedanib: HR: 0.31, 95%-CI: 0.19-0.53, p < 0.001 & pirfenidone: HR: 0.26, 95%-CI: 0.16-0.42, p < 0.001). Nintedanib and pirfenidone in lower intensities were not associated with worse survival outcomes. CONCLUSION: A substantial proportion of patients with IPF receive reduced antifibrotic treatment to ameliorate the side effects associated with a full dosage regime. Treatment with nintedanib and pirfenidone, independent of treatment intensity, was preferable over no antifibrotic treatment in improving survival and reduced dose appears to be a good alternative if full dose is not tolerated.

Incidence, prevalence and regional distribution of systemic sclerosis and related interstitial lung Disease: A nationwide retrospective cohort study.

OBJECTIVE: To investigate incidence and prevalence of Systemic Sclerosis (SSc) and association with interstitial lung disease (SSc-ILD) in a nationwide population-based study. METHODS: Patients with an incident diagnosis of SSc in 2000-2016 were identified in the Danish National Patient Registry and categorised based on diagnosis of ILD. Incidence- and prevalence proportions were calculated based on the annual population estimates. A cox proportional hazards model was used to evaluate the association between age, sex, region and marital status and presence of ILD. RESULTS: In total, 1869 patients with SSc were identified; 275 patients (14.7%) had SSc-ILD. The majority of patients were females (75.5%). The percentage of males was higher in SSc-ILD than in SSc alone (30.9% and 23.4%, p = 0.008). Median time from SSc to ILD diagnosis was 1.4 years (range 0-14.2). ILD was diagnosed from ≤4 years before to ≥7 years after SSc. Development of ILD was associated with male gender (HR 1.75, 95% CI 1.15-2.66), age 41-50 (HR 1.81, 95% CI 1.07-3.05) and residency in the North Denmark Region (HR 1.95, 9 5% CI 1.12-3.40). Mean annual incidence proportion of SSc was 2.9/100,000 and mean annual prevalence proportion was 16.8/100,000. The incidence remained stable, but prevalence proportion increased from 14.1 - 16.5/100,000 in 2000-2008 to 17.9-19.2/100,000 in 2009-2016. CONCLUSION: The prevalence of SSc increased during the study period, while the incidence remained stable. The prevalence of SSc-ILD was 14.7% and thus less frequent than expected. Male sex and age between 41 and 50 years were associated with ILD.

Longitudinal serological assessment of type VI collagen turnover is related to progression in a real-world cohort of idiopathic pulmonary fibrosis.

BACKGROUND: Remodeling of the extracellular matrix (ECM) is a central mechanism in the progression of idiopathic pulmonary fibrosis (IPF), and remodeling of type VI collagen has been suggested to be associated with disease progression. Biomarkers that reflect and predict the progression of IPF would provide valuable information for clinicians when treating IPF patients. METHODS: Two serological biomarkers reflecting formation (PRO-C6) and degradation (C6M) of type VI collagen were evaluated in a real-world cohort of 178 newly diagnoses IPF patients. All patients were treatment naïve at the baseline visit. Blood samples and clinical data were collected from baseline, six months, and 12 months visit. The biomarkers were measured by competitive ELISA using monoclonal antibodies. RESULTS: Patients with progressive disease had higher (P = 0.0099) serum levels of PRO-C6 compared to those with stable disease over 12 months with an average difference across all timepoints of 12% (95% CI 3-22), whereas C6M levels tended (P = 0.061) to be higher in patients with progressive disease compared with stable patients over 12 months with an average difference across all timepoints of 12% (95% CI - 0.005-27). Patients who did not receive antifibrotic medicine had a greater increase of C6M (P = 0.043) compared to treated patients from baseline over 12 months with an average difference across all timepoints of 12% (95% CI - 0.07-47). There were no differences in biomarker levels between patients receiving pirfenidone or nintedanib. CONCLUSIONS: Type VI collagen formation was related to progressive disease in patients with IPF in a real-world cohort and antifibrotic therapy seemed to affect the degradation of type VI collagen. Type VI collagen formation and degradation products might be potential biomarkers for disease progression in IPF.

High turnover of types III and VI collagen in progressive idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: Prediction of idiopathic pulmonary fibrosis (IPF) progression is vital for the choice and timing of treatment and patient follow-up. This could potentially be achieved by prognostic blood biomarkers of extracellular matrix (ECM) remodelling. METHODS: Neoepitope biomarkers of types III and VI collagen turnover (C3M, C6M, PRO-C3 and PRO-C6) were measured in 185 patients with newly diagnosed IPF. Disease severity at baseline and progression over 6 months was assessed by lung function tests and 6-min walk tests. All-cause mortality was assessed over a 3-year follow-up period. RESULTS: High baseline levels of C3M, C6M, PRO-C3 and PRO-C6 were associated with more advanced disease at the time of diagnosis. Baseline levels of C6M and PRO-C3 were also associated with mortality over 3 years of follow-up (hazard ratio [HR]: 2.3, 95% CI: 1.3-3.9, p = 0.002 and HR: 1.8, 95% CI: 1.1-3.0, p = 0.03). Patients with several increased biomarkers at baseline, representing a high ECM remodelling phenotype, had more advanced disease at baseline, higher risk of progression or death at 6 months (OR: 1.4, 95% CI: 1.1-1.8, p = 0.002) and higher mortality over 3 years of follow-up (HR: 2.4, 95% CI: 1.3-4.5, p = 0.007). CONCLUSION: Blood biomarkers of types III and VI collagen turnover, assessed at the time of diagnosis, are associated with several indices of disease severity, short-term progression and long-term mortality. These biomarkers can help to identify patients with a high ECM remodelling phenotype at high risk of disease progression and death.

Increased respiratory morbidity in individuals with interstitial lung abnormalities.

BACKGROUND: Interstitial lung abnormalities (ILA) are common in participants of lung cancer screening trials and broad population-based cohorts. They are associated with increased mortality, but less is known about disease specific morbidity and healthcare utilisation in individuals with ILA. METHODS: We included all participants from the screening arm of the Danish Lung Cancer Screening Trial with available baseline CT scan data (n = 1990) in this cohort study. The baseline scan was scored for the presence of ILA and patients were followed for up to 12 years. Data about all hospital admissions, primary healthcare visits and medicine prescriptions were collected from the Danish National Health Registries and used to determine the participants' disease specific morbidity and healthcare utilisation using Cox proportional hazards models. RESULTS: The 332 (16.7%) participants with ILA were more likely to be diagnosed with one of several respiratory diseases, including interstitial lung disease (HR: 4.9, 95% CI: 1.8-13.3, p = 0.008), COPD (HR: 1.7, 95% CI: 1.2-2.3, p = 0.01), pneumonia (HR: 2.0, 95% CI: 1.4-2.7, p <  0.001), lung cancer (HR: 2.7, 95% CI: 1.8-4.0, p <  0.001) and respiratory failure (HR: 1.8, 95% CI: 1.1-3.0, p = 0.03) compared with participants without ILA. These findings were confirmed by increased hospital admission rates with these diagnoses and more frequent prescriptions for inhalation medicine and antibiotics in participants with ILA. CONCLUSIONS: Individuals with ILA are more likely to receive a diagnosis and treatment for several respiratory diseases, including interstitial lung disease, COPD, pneumonia, lung cancer and respiratory failure during long-term follow-up.

Interstitial lung abnormalities are associated with increased mortality in smokers.

OBJECTIVE: The aim of this study was to investigate whether smokers with incidental findings of interstitial lung abnormalities have an increased mortality during long-term follow-up, and review the contributing causes of death. METHODS: Baseline CT scans of 1990 participants from the Danish Lung Cancer Screening Trial were qualitatively assessed for predefined interstitial lung abnormalities of any severity. Inclusion criteria for this lung cancer screening trial included current or former smoking, > 20 pack-years, and age 50-70 years. Patients were followed up for up to 12 years. RESULTS: We found interstitial lung abnormalities in 332 participants (16.7%). Interstitial lung abnormalities were associated with increased all-cause mortality in the full cohort (HR: 2.0, 95% CI: 1.4-2.7, P < 0.001) and in lung cancer-free participants (HR: 1.6, 95% CI: 1.1-2.4, P = 0.007). The findings were associated with death from lung cancer (HR: 3.2, 95% CI: 1.7-6.2, P < 0.001) and non-pulmonary malignancies (HR: 2.1, 95% CI: 1.1-4.0, P = 0.02). Participants with fibrotic and non-fibrotic interstitial lung abnormalities had similar survival. CONCLUSION: Interstitial lung abnormalities were common in this lung cancer screening population of relatively healthy smokers and were associated with mortality regardless of the interstitial morphological phenotype. The increased mortality was partly due to an association with lung cancer and non-pulmonary malignancies.

Visual assessment of early emphysema and interstitial abnormalities on CT is useful in lung cancer risk analysis.

OBJECTIVES: Screening for lung cancer should be limited to a high-risk-population, and abnormalities in low-dose computed tomography (CT) screening images may be relevant for predicting the risk of lung cancer. Our aims were to compare the occurrence of visually detected emphysema and interstitial abnormalities in subjects with and without lung cancer in a screening population of smokers. METHODS: Low-dose chest CT examinations (baseline and latest possible) of 1990 participants from The Danish Lung Cancer Screening Trial were independently evaluated by two observers who scored emphysema and interstitial abnormalities. Emphysema (lung density) was also measured quantitatively. RESULTS: Emphysema was seen more frequently and its extent was greater among participants with lung cancer on baseline (odds ratio (OR), 1.8, p = 0.017 and p = 0.002) and late examinations (OR 2.6, p < 0.001 and p < 0.001). No significant difference was found using quantitative measurements. Interstitial abnormalities were more common findings among participants with lung cancer (OR 5.1, p < 0.001 and OR 4.5, p < 0.001).There was no association between presence of emphysema and presence of interstitial abnormalities (OR 0.75, p = 0.499). CONCLUSIONS: Even early signs of emphysema and interstitial abnormalities are associated with lung cancer. Quantitative measurements of emphysema-regardless of type-do not show the same association. KEY POINTS: • Visually detected emphysema on CT is more frequent in individuals who develop lung cancer. • Emphysema grading is higher in those who develop lung cancer. • Interstitial abnormalities, including discrete changes, are associated with lung cancer. • Quantitative lung density measurements are not useful in lung cancer risk prediction. • Early CT signs of emphysema and interstitial abnormalities can predict future risk.

Rituximab-induced interstitial lung disease: five case reports.

Rituximab (RTX), a mouse/human chimeric anti-CD20 IgG1 monoclonal antibody has been effectively used as a single agent or in combination with chemotherapy regimen to treat lymphoma since 1997. In addition, it has been used to treat idiopathic thrombocytopenic purpura, systemic lupus erythematous, rheumatoid arthritis, and autoimmune hemolytic anemia. Recently, RTX has also been suggested for the treatment of certain connective tissue disease-related interstitial lung diseases (ILD) and hypersensitivity pneumonitis. Rare but serious pulmonary adverse reactions are reported. To raise awareness about this serious side effect of RTX treatment, as the indication for its use increases with time, we report five cases of probable RTX-ILD and discuss the current literature on this potentially lethal association.

Correlation Between Emphysema and Lung Function in Healthy Smokers and Smokers With COPD.

Background: Emphysema is an important component of COPD; however, in previous studies of the correlation between airflow limitation (AFL) and computed tomography (CT) lung density as a surrogate for emphysema has varied. We hypothesised a good correlation between lung function (forced expiratory volume in first second [FEV1]) and emphysema (15th percentile density [PD15]) and that this correlation also exists between loss of lung tissue and decline in lung function even within the time frame of longitudinal studies of relatively short duration. Methods: We combined 2 large longitudinal studies (the Danish Lung Cancer Screening Trial [DLCST] and the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints [ECLIPSE]) of smokers or former smokers, with a wide range of AFL and CT lung density, and analysed data from 2148 participants who did not change smoking habits and who had at least 2 CT scans and 2 FEV1 measurements at least 3 years apart. Results: Baseline correlation between FEV1 and PD15 was high (r=0.716, 95% confidence interval [CI]: 0.694-0.736, p<0.001) indicating that at least half of the variation in FEV1 can be explained by variation in CT lung density. Correlation between the decline in FEV1 and progression of PD15 was considerably weaker (r= 0.081, 95% CI: 0.038-0.122, p<0.001). Conclusions: Correlation is very high between lung density and lung function in a broad spectrum of smokers and ex-smokers. In contrast, the temporal associations (slopes) are weakly correlated, probably due to uncertainty in the estimation of slopes within a time frame of 3-4 years.

Emphysema progression is visually detectable in low-dose CT in continuous but not in former smokers.

OBJECTIVES: To evaluate interobserver agreement and time-trend in chest CT assessment of emphysema, airways, and interstitial abnormalities in a lung cancer screening cohort. METHODS: Visual assessment of baseline and fifth-year examination of 1990 participants was performed independently by two observers. Results were standardised by means of an electronic score sheet; kappa and time-trend analyses were performed. RESULTS: Interobserver agreement was substantial in early emphysema diagnosis; highly significant (p < 0.001) time-trends in both emphysema presence and grading were found (higher prevalence and grade of emphysema in late CT examinations). Significant progression in emphysema was seen in continuous smokers, but not in former smokers. Agreement on centrilobular emphysema subtype was substantial; agreement on paraseptal subtype, moderate. Agreement on panlobular and mixed subtypes was only fair. Agreement was fair regarding airway analysis. Interstitial abnormalities were infrequent in the cohort, and agreement on these was fair to moderate. A highly significant time-trend was found regarding interstitial abnormalities, which were more frequent in late examinations. CONCLUSIONS: Visual scoring of chest CT is able to characterise the presence, pattern, and progression of early emphysema. Continuous smokers progress; former smokers do not. KEY POINTS: • Substantial interobserver consistency in determining early-stage emphysema in low-dose CT. • Longitudinal analyses show clear time-trends for emphysema presence and grading. • For continuous smokers, progression of emphysema was seen in all lung zones. • For former smokers, progression of emphysema was undetectable by visual assessment. • Onset and progression of interstitial abnormalities are visually detectable.

Profuse coarse pulmonary nodules in a patient with lymphangioleiomyomatosis: thirty-three years of follow-up.

Lymphangioleiomyomatosis (LAM) is a rare disease characterized by progressive cystic destruction of the lungs. We present an unusual radiological presentation of lymphangioleiomyomatosis in a patient followed for 33 years with profuse coarse lung nodules in addition to the classical cystic lesions. We believe that this report might support the case for considering LAM a low-malignant neoplasm.

Analysis of FEV1 decline in relatively healthy heavy smokers: implications of expressing changes in FEV1 in relative terms.

Progressive decline in lung function has been widely accepted as the hallmark of chronic obstructive pulmonary disease (COPD); however, recent evidence indicates that the rate of decline measured as decline in forced expiratory volume in one second (FEV1) is higher in mild to moderate COPD than in severe COPD. Usually changes in FEV1 are measured in ml that is "absolute"; however, changes can also be measured "relative" as a percentage of the actual FEV1. We hypothesize that relative measurements could be more appropriate than absolute measurements for describing changes in lung function. We analyzed data from 3,218 relatively healthy heavy smokers who participated in the Danish Lung Cancer Screening Trial. The influences of age, sex, height, body mass index, smoking, and severity of airflow limitation on FEV1 were analyzed in mixed effects models. In absolute terms those with the best lung function consistently showed the steepest decline, whereas in relative terms most fast decliners are found among those with low lung function. Measuring changes in relative terms implied statistically significant acceleration of decline with advancing age, smoking (pack-years) and severity of airflow limitation. Relative measurements may lead to a better understanding of changes in lung function. Smoking and severity of airflow limitation speed up the loss of lung function, and this emphasizes the importance of abstaining from smoking the sooner the better. Measuring changes in relative terms could have important implications for the interpretation of results from clinical trials where FEV1 is the primary outcome. DLCST; www.ClinicalTrials.org , registration number: NCT00496977.

Factors influencing the decline in lung density in a Danish lung cancer screening cohort.

Lung cancer screening trials provide an opportunity to study the natural history of emphysema by using computed tomography (CT) lung density as a surrogate parameter. In the Danish Lung Cancer Screening Trial, 2,052 participants were included. At screening rounds, smoking habits were recorded and spirometry was performed. CT lung density was measured as the volume-adjusted 15th percentile density (PD15). A mixed effects model was used with former smoking males with <30 pack-yrs and without airflow obstruction (AFO) at entry as a reference group. At study entry, 893 (44%) participants had AFO. For the reference group, PD15 was 72.6 g·L(-1) with an annual decline of -0.33 g·L(-1). Female sex and current smoking increased PD15 at baseline, 17.3 g·L(-1) (p<0.001) and 10 g·L(-1) (p<0.001), respectively; and both increased the annual decline in PD15 (female: -0.3 g·L(-1); current smoking: -0.4 g·L(-1)). The presence and severity of AFO was a strong predictor of low PD15 at baseline (Global Initiative for Chronic Obstructive Lung Disease (GOLD) I: -1.4 g·L(-1); GOLD II: -6.3 g·L(-1); GOLD III: -17 g·L(-1)) and of increased annual decline in PD15 (GOLD I: -0.2 g·L(-1); GOLD II: -0.5 g·L(-1); GOLD III: -0.5 g·L(-1)). Female sex, active smoking and the presence of AFO are associated with accelerated decline in lung density.

Rapid fall in lung density following smoking cessation in COPD.

INTRODUCTION: Whether smoking-induced lung inflammation subsides after smoking cessation is currently a matter of debate. We used computed tomography (CT) to evaluate the effect of smoking cessation on lung density in patients with COPD. MATERIAL AND METHODS: Thirty-six patients quit smoking out of 254 current smokers with COPD who were followed with annual CT and lung function tests (LFT) for 2?4 years as part of a randomised placebo-controlled trial of the effect of inhaled budesonide on CT-lung density. Lung density was expressed as the 15th percentile density (PD15) and relative area of emphysema below -910 HU (RA-910). From the time-trends in the budesonide and placebo groups the expected CT-lung densities at the first visit after smoking cessation were calculated by linear regression and compared to the observed densities. RESULTS: Following smoking cessation RA-910 increased by 2.6% (p = 0.003) and PD15 decreased by -4.9 HU (p = 0.0002). Furthermore, changes were larger in the budesonide group than the placebo group (PD15: -7.1 vs -2.8 HU. RA-910 3.7% vs 1.7%). These differences were, however, not statistically significant. The LFT parameters (FEV(1) and diffusion capacity) were not significantly influenced by smoking cessation. CONCLUSION: Inflammation partly masks the presence of emphysema on CT and smoking cessation results in a paradoxical fall in lung density, which resembles rapid progression of emphysema. This fall in density is probably due to an anti-inflammatory effect of smoking cessation.

A texton-based approach for the classification of lung parenchyma in CT images.

In this paper, a texton-based classification system based on raw pixel representation along with a support vector machine with radial basis function kernel is proposed for the classification of emphysema in computed tomography images of the lung. The proposed approach is tested on 168 annotated regions of interest consisting of normal tissue, centrilobular emphysema, and paraseptal emphysema. The results show the superiority of the proposed approach to common techniques in the literature including moments of the histogram of filter responses based on Gaussian derivatives. The performance of the proposed system, with an accuracy of 96.43%, also slightly improves over a recently proposed approach based on local binary patterns.

Quantitative analysis of pulmonary emphysema using local binary patterns.

We aim at improving quantitative measures of emphysema in computed tomography (CT) images of the lungs. Current standard measures, such as the relative area of emphysema (RA), rely on a single intensity threshold on individual pixels, thus ignoring any interrelations between pixels. Texture analysis allows for a much richer representation that also takes the local structure around pixels into account. This paper presents a texture classification-based system for emphysema quantification in CT images. Measures of emphysema severity are obtained by fusing pixel posterior probabilities output by a classifier. Local binary patterns (LBP) are used as texture features, and joint LBP and intensity histograms are used for characterizing regions of interest (ROIs). Classification is then performed using a k nearest neighbor classifier with a histogram dissimilarity measure as distance. A 95.2% classification accuracy was achieved on a set of 168 manually annotated ROIs, comprising the three classes: normal tissue, centrilobular emphysema, and paraseptal emphysema. The measured emphysema severity was in good agreement with a pulmonary function test (PFT) achieving correlation coefficients of up to |r| = 0.79 in 39 subjects. The results were compared to RA and to a Gaussian filter bank, and the texture-based measures correlated significantly better with PFT than did RA.

The effect of inhaled corticosteroids on the development of emphysema in smokers assessed by annual computed tomography.

The objective was to evaluate the effect of inhaled corticosteroids on disease progression in smokers with moderate to severe chronic obstructive pulmonary disease (COPD), as assessed by annual computed tomography (CT) using lung density (LD) measurements. Two hundred and fifty-four current smokers with COPD were randomised to treatment with either an inhaled corticosteroids (ICS), budesonide 400 microg bid, or placebo. COPD was defined as FEV(1) < or = 70% pred, FEV(1)/FVC < or = 60% and no reversibility to beta(2)-agonists and oral corticosteroids. The patients were followed for 2-4 years with biannual spirometry and annual CT and comprehensive lung function tests (LFT). CT images were analysed using Pulmo-CMS software. LD was derived from a pixel-density histogram of the whole lung as the 15th percentile density (PD15) and the relative area of emphysema at a threshold of -910 Hounsfield units (RA-910), and both were volume-adjusted to predicted total lung capacity. At baseline, mean age was 64 years and 64 years; mean number of pack-years was 56 and 56; mean FEV(1) was 1.53 L (51% pred) and 1.53 L (53% pred); mean PD15 was 103 g/L and 104 g/L; and mean RA-910 was 14% and 13%, respectively, for the budesonide and placebo groups. The annual fall in PD15 was -1.12 g/L in the budesonide group and -1.81 g/L in the placebo group (p = 0.09); the annual increase in RA-910 was 0.4% in the budesonide group and 1.1% in the placebo group (p = 0.02). There was no difference in annual decline in FEV(1) between ICS (-54 mL) and placebo (-56 mL) (p = 0.89). Long-term budesonide inhalation shows a non-significant trend towards reducing the progression of emphysema as determined by the CT-derived 15th percentile lung density from annual CT scans in current smokers with moderate to severe COPD.

Volume correction in computed tomography densitometry for follow-up studies on pulmonary emphysema.

Lung densitometry in drug evaluation trials can be confounded by changes in inspiration levels between computed tomography (CT) scans, limiting its sensitivity to detect changes over time. Therefore our aim was to explore whether the sensitivity of lung densitometry could be improved by correcting the measurements for changes in lung volume, based on the estimated relation between density (as measured with the 15th percentile point) and lung volume. We compared four correction methods, using CT data of 143 patients from five European countries. Patients were scanned, generally twice per visit, at baseline and after 2.5 years. The methods included one physiological model and three linear mixed-effects models using a volume-density relation: (1) estimated over the entire population with one scan per visit (model A) and two scans per visit (model B); and (2) estimated for each patient individually (model C). Both log-transformed and original volume and density values were evaluated and the differences in goodness-of-fit between methods were tested. Model C fitted best (P < 0.0001, P < 0.0001, and P = 0.064), when two scans were available. The most consistent progression estimation was obtained between sites, when both volume and density were log-transformed. Sensitivity was improved using repeated CT scans by applying volume correction to individual patient data. Volume correction reduces the variability in progression estimation by a factor of two, and is therefore recommended.

Texture classification in lung CT using local binary patterns.

In this paper we propose to use local binary patterns (LBP) as features in a classification framework for classifying different texture patterns in lung computed tomography. Image intensity is included by means of the joint LBP and intensity histogram, and classification is performed using the k nearest neighbor classifier with histogram similarity as distance measure. The proposed method is evaluated on a set of 168 regions of interest comprising normal tissue and different emphysema patterns, and compared to a filter bank based on Gaussian derivatives. The joint LBP and intensity histogram, achieving a classification accuracy of 95.2%, shows superior performance to using the common approach of taking moments of the filter response histograms as features, and slightly better performance than using the full filter response histograms instead. Classification results are better than some of those previously reported in the literature.