Emphysema distribution and annual changes in pulmonary function in male patients with chronic obstructive pulmonary disease

Background

The progression of chronic obstructive pulmonary disease (COPD) considerably varies among patients. Those with emphysema identified by quantitative computed tomography (CT) are associated with the rapid progression assessed by forced expiratory volume in one second (FEV₁). However, whether the rate of the decline in lung function is independently affected by the regional distribution or the severity of emphysema in the whole lung is unclear.

Methods

We followed up 131 male patients with COPD for a median of 3.7 years. We measured wall area percent (WA%) in right apical segmental bronchus, total lung volume, percent low attenuation volume (LAV%), and the standard deviation (SD) of LAV% values from CT images of 10 isovolumetric partitions (SD-LAV) as an index of cranial-caudal emphysema heterogeneity. Annual changes in FEV₁ were then determined using a random coefficient model and relative contribution of baseline clinical parameters, pulmonary function, and CT indexes including LAV%, SD-LAV, and WA% to annual changes in FEV₁ were examined.

Results

The mean (SD) annual change in FEV₁ was −44.4 (10.8) mL. Multivariate random coefficient model showed that higher baseline FEV₁, higher LAV%, current smoking, and lower SD-LAV independently contributed to an excessive decline in FEV₁, whereas ratio of residual volume to total lung capacity, ratio of diffusing capacity to alveolar ventilation, and WA% did not, after adjusting for age, height, weight, and ratio of CT-measured total lung volume to physiologically-measured total lung capacity.

Conclusions

A more homogeneous distribution of emphysema contributed to an accelerated decline in FEV₁ independently of baseline pulmonary function, whole-lung emphysema severity, and smoking status. In addition to whole-lung analysis of emphysema, CT assessment of the cranial-caudal distribution of emphysema might be useful for predicting rapid, progressive disease and for developing a targeted strategy with which to prevent disease progression.     

Is the Improvement of CF Patients,Hospitalized for Pulmonary Exacerbation,Correlated to a Decrease in Bacterial Load?

Background

Cystic Fibrosis (CF) patients are vulnerable to airway colonization with Pseudomonas aeruginosa. In case eradication fails after antibiotic treatment, patients become chronically colonized with P. aeruginosa, with recurrent pulmonary exacerbation, for which patients typically are hospitalized for 2 weeks and receive intravenous antibiotic treatment. Normally, improvement of the patients'' health is established.

Aim

Determination of the correspondence between patient improvement and changes of the P. aeruginosa and total bacterial load in the sputum.

Methods

Eighteen CF patients with exacerbation were included for a total of 27 hospitalization episodes. At day 1, 8 and 15, inflammation and lung function parameters were determined, together with the P. aeruginosa load in the sputum using culture, quantitative PCR (qPCR) and propidium monoazide qPCR.

Results

Patients improved during hospitalization (decrease in levels of C-reactive protein, white blood cell counts and erythrocyte sedimentation rate, increase of FEV₁), reaching normal values already after one week. Also the P. aeruginosa load and the total bacterial load decreased during the first week of antibiotic treatment (p<0.05), except for patients with a low lung function (FEV₁≤39.4%), for whom no significant decrease of P. aeruginosa was established. Comparison of culture-based and propidium monoazide qPCR-based quantification of P. aeruginosa showed that at the end of the treatment on average 62% of the P. aeruginosa cells are not cultivable, indicating that many cells are alive but dormant, or dead but still structurally intact.

Conclusion

Improvement of the clinical status is accompanied with a decrease of the P. aeruginosa load, whereby both occur mainly during the first week of antibiotic treatment. However, for patients with a low lung function, no decrease of the P. aeruginosa load is observed. Comparison of detection techniques shows that a large amount of noncultivable or dead bacteria are present in the samples.     

Sequential analysis of surfactant,lung function and inflammation in cystic fibrosis patients

Background

In a cross-sectional analysis of cystic fibrosis (CF) patients with mild lung disease, reduced surfactant activity was correlated to increased neutrophilic airway inflammation, but not to lung function. So far, longitudinal measurements of surfactant function in CF patients are lacking and it remains unclear how these alterations relate to the progression of airway inflammation as well as decline in pulmonary function over time.

Methods

As part of the BEAT trial, a longitudinal study to assess the course of airway inflammation in CF, we studied lung function, surfactant function and endobronchial inflammation using bronchoalveolar lavage fluid from 20 CF patients with normal pulmonary function (median FEV₁ 94% of predicted) at three times over a three year period.

Results

There was a progressive loss of surfactant function, assessed as minimal surface tension. The decline in surfactant function was negatively correlated to an increase in neutrophilic inflammation and a decrease in lung function, assessed by FEV₁, MEF_75/25%VC, and MEF_25%VC. The concentrations of the surfactant specific proteins A, C and D did not change, whereas SP-B increased during this time period.

Conclusion

Our findings suggest a link between loss of surfactant function driven by progressive airway inflammation and loss of small airway function in CF patients with limited lung disease.     

Withdrawal of inhaled corticosteroids can be safe in COPD patients at low risk of exacerbation: a real-life study on the appropriateness of treatment in moderate COPD patients (OPTIMO)

Background

It has been suggested that withdrawal of inhaled corticosteroids (ICS) in COPD patients on maintenance treatment results in deterioration of symptoms, lung function and exacerbations. The aim of this real-life, prospective, multicentric study was to investigate whether withdrawal of ICS in COPD patients at low risk of exacerbation is linked to a deterioration in lung function and symptoms and to a higher frequency of exacerbations.

Methods

914 COPD patients, on maintenance therapy with bronchodilators and ICS, FEV₁>50% predicted, and <2 exacerbations/year were recruited. Upon decision of the primary physicians, 59% of patients continued their ICS treatment whereas in 41% of patients ICS were withdrawn and regular therapy was continued with long-acting bronchodilators mostly (91% of patients). FEV₁, CAT (COPD Assessment Test), and occurrence of exacerbations were measured at the beginning (T0) and at the end (T6) of the 6 months observational period.

Results

816 patients (89.3%) concluded the study. FEV₁, CAT and exacerbations history were similar in the two groups (ICS and no ICS) at T0 and at T6. We did not observe any deterioration of lung function symptoms, and exacerbation rate between the two groups at T0 and T6.

Conclusions

We conclude that the withdrawal of ICS, in COPD patients at low risk of exacerbation, can be safe provided that patients are left on maintenance treatment with long-acting bronchodilators.     

Adverse health consequences in COPD patients with rapid decline in FEV1 - evidence from the UPLIFT trial

Background

The rate of decline in forced expiratory volume in 1 second (FEV₁) is representative of the natural history of COPD. Sparse information exists regarding the associations between the magnitude of annualised loss of FEV₁ with other endpoints.

Methods

Retrospective analysis of UPLIFT^® trial (four-year, randomized, double-blind, placebo-controlled trial of tiotropium 18 μg daily in chronic obstructive pulmonary disease [COPD], n = 5993). Decline of FEV₁ was analysed with random co-efficient regression. Patients were categorised according to quartiles based on the rate of decline (RoD) in post-bronchodilator FEV_1. The St George''s Respiratory Questionnaire (SGRQ) total score, exacerbations and mortality were assessed within each quartile.

Results

Mean (standard error [SE]) post-bronchodilator FEV₁ increased in the first quartile (Q1) by 37 (1) mL/year. The other quartiles showed annualised declines in FEV₁ (mL/year) as follows: Q2 = 24 (1), Q3 = 59 (1) and Q4 = 125 (2). Age, gender, respiratory medication use at baseline and SGRQ did not distinguish groups. The patient subgroup with the largest RoD had less severe lung disease at baseline and contained a higher proportion of current smokers. The percentage of patients with ≥ 1 exacerbation showed a minimal difference from the lowest to the largest RoD, but exacerbation rates increased with increasing RoD. The highest proportion of patients with ≥ 1 hospitalised exacerbation was in Q4 (Q1 = 19.5% [tiotropium], 26% [control]; Q4 = 33.8% [tiotropium] and 33.1% [control]). Time to first exacerbation and hospitalised exacerbation was shorter with increasing RoD. Rate of decline in SGRQ increased in direct proportion to each quartile. The group with the largest RoD had the highest mortality.

Conclusion

Patients can be grouped into different RoD quartiles with the observation of different clinical outcomes indicating that specific (or more aggressive) approaches to management may be needed.

Trial Registration

ClinicalTrials.gov number, {"type":"clinical-trial","attrs":{"text":"NCT00144339","term_id":"NCT00144339"}}NCT00144339     

Factors Associated with Lung Function Decline in Patients with Non-Tuberculous Mycobacterial Pulmonary Disease

Background

There is paucity of risk factors on lung function decline among patients with non-tuberculous mycobacteria (NTM) pulmonary disease in literature.

Methods

Patients with NTM pulmonary disease between January 2000 and April 2011 were retrospectively selected. Sixty-eight patients had at least two pulmonary function tests within a mean follow-up period of 47 months.

Results

Sixty-eight patients were included. They had a median age of 65 years and 65% had impaired lung function (Forced expiratory volume in 1 second [FEV₁] <80% of predicted value). The mean FEV₁ decline was 48 ml/year. By linear regression, younger age (beta: 0.472, p<0.001), initial FEV₁>50% of predicted value (beta: 0.349, p = 0.002), male sex (beta: 0.295, p = 0.018), bronchiectasis pattern (beta: 0.232, p = 0.035), and radiographic score >3 (beta: 0.217, p = 0.049) were associated with greater FEV₁ decline. Initial FEV₁>50% of predicted value (beta: 0.263, p = 0.032) was also associated with greater FVC annual decline, whereas M. kansasii pulmonary disease was marginally associated with greater annual FVC decline (beta: 0.227, p = 0.062).

Conclusions

NTM pulmonary disease is associated with greater decline in lung function in patients who are young, male, with bronchiectasis, and with a high radiographic score. Special attention should be given to patients with these risk factors.     

Matrix metalloproteinase-9 predicts pulmonary status declines in α1-antitrypsin deficiency

Background

Matrix metalloproteinase-9 (MMP-9) may be important in the progression of emphysema, but there have been few longitudinal clinical studies of MMP-9 including pulmonary status and COPD exacerbation outcomes.

Methods

We utilized data from the placebo arm (n = 126) of a clinical trial of patients with alpha₁-antitrypsin deficiency (AATD) and emphysema to examine the links between plasma MMP-9 levels, pulmonary status, and COPD exacerbations over a one year observation period. Pulmonary function, computed tomography lung density, incremental shuttle walk test (ISWT), and COPD exacerbations were assessed at regular intervals over 12 months. Prospective analyses used generalized estimating equations to incorporate repeated longitudinal measurements of MMP-9 and all endpoints, controlling for age, gender, race-ethnicity, leukocyte count, and tobacco history. A secondary analysis also incorporated highly-sensitive C-reactive protein levels in predictive models.

Results

At baseline, higher plasma MMP-9 levels were cross-sectionally associated with lower FEV₁ (p = 0.03), FVC (p < 0.001), carbon monoxide transfer factor (p = 0.03), resting oxygen saturation (p = 0.02), and ISWT distance walked (p = 0.02) but were not associated with radiographic lung density or total lung capacity (TLC). In longitudinal analyses, MMP-9 predicted a further decline in transfer factor (p = 0.04) and oxygen saturation (p < 0.001). MMP-9 also predicted worsening lung density (p = 0.003), increasing TLC (p = 0.02), and more frequent COPD exacerbations over follow-up (p = 0.003). Controlling additionally for hs-CRP levels did not substantively change the longitudinal associations between MMP-9 and these outcomes.

Conclusions

Increased plasma MMP-9 levels generally predicted pulmonary status declines, including worsening transfer factor and lung density as well as greater COPD exacerbations in AATD-associated emphysema.     

Is sirolimus a therapeutic option for patients with progressive pulmonary lymphangioleiomyomatosis?

Background

Lymphangioleiomyomatosis (LAM) is a rare lung disease characterised by progressive airflow obstruction. No effective medical treatment is available but therapy with sirolimus has shown some promise. The aim of this observational study was to evaluate sirolimus in progressive LAM.

Methods

Sirolimus (trough level 5 - 10 ng/ml) was administered to ten female patients (42.4 ± 11.9 years) with documented progression. Serial pulmonary function tests and six-minute-walk-distance (6-MWD) assessments were performed.

Results

The mean loss of FEV₁ was -2.30 ± 0.52 ml/day before therapy and a significant mean gain of FEV₁ of 1.19 ± 0.26 ml/day was detected during treatment (p = 0.001). Mean FEV₁ and FVC at baseline were 1.12 ± 0.15 l (36.1 ± 4.5%pred.) and 2.47 ± 0.25 l (69.2 ± 6.5%pred.), respectively. At three and six months during follow-up a significant increase of FEV₁ and FVC was demonstrated (3 months ΔFEV₁: 220 ± 82 ml, p = 0.024; 6 months ΔFEV₁: 345 ± 58 ml, p = 0.001); (3 months ΔFVC: 360 ± 141 ml, p = 0.031; 6 months ΔFVC: 488 ± 138 ml, p = 0.006). Sirolimus was discontinued in 3 patients because of serious recurrent lower respiratory tract infection or sirolimus-induced pneumonitis. No deaths and no pneumothoraces occurred during therapy.

Conclusions

Our data suggest that sirolimus might be considered as a therapeutic option in rapidly declining LAM patients. However, sirolimus administration may be associated with severe respiratory adverse events requiring treatment cessation in some patients. Moreover, discontinuation of sirolimus is mandatory prior to lung transplantation.     

Inflammation and Airway Microbiota during Cystic Fibrosis Pulmonary Exacerbations

Background

Pulmonary exacerbations (PEx), frequently associated with airway infection and inflammation, are the leading cause of morbidity in cystic fibrosis (CF). Molecular microbiologic approaches detect complex microbiota from CF airway samples taken during PEx. The relationship between airway microbiota, inflammation, and lung function during CF PEx is not well understood.

Objective

To determine the relationships between airway microbiota, inflammation, and lung function in CF subjects treated for PEx.

Methods

Expectorated sputum and blood were collected and lung function testing performed in CF subjects during early (0–3d.) and late treatment (>7d.) for PEx. Sputum was analyzed by culture, pyrosequencing of 16S rRNA amplicons, and quantitative PCR for total and specific bacteria. Sputum IL-8 and neutrophil elastase (NE); and circulating C-reactive protein (CRP) were measured.

Results

Thirty-seven sputum samples were collected from 21 CF subjects. At early treatment, lower diversity was associated with high relative abundance (RA) of Pseudomonas (r = −0.67, p<0.001), decreased FEV_1% predicted (r = 0.49, p = 0.03) and increased CRP (r = −0.58, p = 0.01). In contrast to Pseudomonas, obligate and facultative anaerobic genera were associated with less inflammation and higher FEV₁. With treatment, Pseudomonas RA and P. aeruginosa by qPCR decreased while anaerobic genera showed marked variability in response. Change in RA of Prevotella was associated with more variability in FEV₁ response to treatment than Pseudomonas or Staphylococcus.

Conclusions

Anaerobes identified from sputum by sequencing are associated with less inflammation and higher lung function compared to Pseudomonas at early exacerbation. CF PEx treatment results in variable changes of anaerobic genera suggesting the need for larger studies particularly of patients without traditional CF pathogens.     

Rate of progression of CT-quantified emphysema in male current and ex-smokers: a follow-up study

Background

Little is known about the factors associated with CT-quantified emphysema progression in heavy smokers. The objective of this study was to investigate the effect of length of smoking cessation and clinical / demographical factors on the rate of emphysema progression and FEV₁-decline in male heavy smokers.

Methods

3,670 male smokers with mean (SD) 40.8 (17.9) packyears underwent chest CT scans and pulmonary function tests at baseline and after 1 and 3 years follow-up. Smoking status (quitted ≥5, ≥1-<5, <1 years or current smoker) was noted. Rate of progression of emphysema and FEV₁-decline after follow-up were assessed by analysis of variance adjusting for age, height, baseline pulmonary function and emphysema severity, packyears, years in study and respiratory symptoms. The quitted ≥5 group was used as reference.

Results

Median (Q1-Q3) emphysema severity,<-950 HU, was 8.8 (5.1 – 14.1) and mean (SD) FEV₁ was 3.4 (0.73) L or 98.5 (18.5) % of predicted. The group quitted ‘>5 years’ showed significantly lower rates of progression of emphysema compared to current smokers, 1.07% and 1.12% per year, respectively (p<0.001). Current smokers had a yearly FEV₁-decline of 69 ml, while subjects quit smoking >5 years had a yearly decline of 57.5 ml (p<0.001).

Conclusion

Quit smoking >5 years significantly slows the rate of emphysema progression and lung function decline.

Trial registration

Registered at http://www.trialregister.nl with trial number ISRCTN63545820.     

Efficacy and safety of once-daily NVA237 in patients with moderate-to-severe COPD: the GLOW1 trial

Background

NVA237 is a once-daily dry-powder formulation of the long-acting muscarinic antagonist glycopyrronium bromide in development for the treatment of chronic obstructive pulmonary disease (COPD). The glycopyrronium bromide in COPD airways clinical study 1 (GLOW1) evaluated the efficacy, safety and tolerability of NVA237 in patients with moderate-to-severe COPD.

Methods

Patients with COPD with a smoking history of ≥ 10 pack-years, post-bronchodilator forced expiratory volume in 1 second (FEV₁) < 80% and ≥ 30% predicted normal and FEV₁/forced vital capacity < 0.70 were enrolled. Patients were randomized to double-blind treatment with NVA237 50 μg once daily or placebo for 26 weeks with inhaled/intranasal corticosteroids or H₁ antagonists permitted in patients stabilized on them prior to study entry. The primary outcome measure was trough FEV₁ at Week 12.

Results

A total of 822 patients were randomized to NVA237 (n = 552) or placebo (n = 270). Least squares mean (± standard error) trough FEV₁ at Week 12 was significantly higher in patients receiving NVA237 (1.408 ± 0.0105 L), versus placebo (1.301 ± 0.0137 L; treatment difference 108 ± 14.8 mL, p < 0.001). Significant improvements in trough FEV₁ were apparent at the end of Day 1 and sustained through Week 26. FEV₁ was significantly improved in the NVA237 group versus placebo throughout the 24-hour periods on Day 1 and at Weeks 12 and 26, and at all other visits and timepoints. Transition dyspnoea index focal scores and St. George''s Respiratory Questionnaire scores were significantly improved with NVA237 versus placebo at Week 26, with treatment differences of 1.04 (p < 0.001) and-2.81 (p = 0.004), respectively. NVA237 significantly reduced the risk of first moderate/severe COPD exacerbation by 31% (p = 0.023) and use of rescue medication by 0.46 puffs per day (p = 0.005), versus placebo. NVA237 was well tolerated and had an acceptable safety profile, with a low frequency of cardiac and typical antimuscarinic adverse effects.

Conclusions

Once-daily NVA237 was safe and well tolerated and provided rapid, sustained improvements in lung function, improvements in dyspnoea, and health-related quality of life, and reduced the risk of exacerbations and the use of rescue medication.

Trial registration

ClinicalTrials.gov: NCT01005901     

CT Air Trapping Is Independently Associated with Lung Function Reduction over Time

Purpose

We aimed to study the association between lung function decline and quantitative computed tomography (CT) air trapping.

Materials and Methods

Current and former heavy smokers in a lung cancer screening trial underwent volumetric low-dose CT in inspiration and expiration. Spirometry was obtained at baseline and after 3 years. The expiratory to inspiratory ratio of mean lung density (E/I-ratio_MLD) was used to quantify air trapping. CT emphysema was defined as voxels in inspiratory CT below −950 Hounsfield Unit. Linear mixed modeling was used to determine the association between CT air trapping and lung function.

Results

We included 985 subjects with a mean age of 61.3 years. Independent of CT emphysema, CT air trapping was significantly associated with a reduction in forced expiratory volume in one second (FEV₁) and the ratio of FEV₁ over the forced vital capacity (FEV₁/FVC); FEV₁ declines with 33 mL per percent increase in CT air trapping, while FEV₁/FVC declines 0.58% per percent increase (both p<0.001). CT air trapping further elicits accelerated loss of FEV₁/FVC (additional 0.24% reduction per percent increase; p = 0.014).

Conclusion

In a lung cancer screening cohort, quantitatively assessed air trapping on low-dose CT is independently associated with reduced lung function and accelerated decline of FEV₁/FVC.     

Lung function,symptoms and inflammation during exacerbations of non-cystic fibrosis bronchiectasis: a prospective observational cohort study

Background

Exacerbations of non-cystic fibrosis bronchiectasis cause significant morbidity but there are few detailed data on their clinical course and associated physiological changes. The biology of an exacerbation has not been previously described.The purpose of this study was to describe changes in lung function, symptoms, health status and inflammation during the development and recovery from community-treated exacerbations.

Methods

This was a prospective observational cohort study of 32 outpatients with non-cystic fibrosis bronchiectasis conducted between August 2010 and August 2012. Patients completed a symptom diary card and measured their peak expiratory flow rate (PEFR) daily. Exacerbations were defined as oral antibiotic treatment taken for a worsening of respiratory symptoms. Symptoms and peak flow at exacerbation were analysed, and further measurements including the COPD Assessment Test (CAT) and inflammatory markers were also compared to baseline values.

Results

At baseline, health status was significantly related to lung function, prognostic severity and systemic inflammation. 51 exacerbations occurred in 22 patients. Exacerbation symptoms began a median (interquartile range) of 4 (2, 7) days before treatment started and the median exacerbation duration was 16 (10, 29) days. 16% had not recovered by 35 days. At exacerbation, mean PEFR dropped by 10.6% (95% confidence interval 6.9-14.2, p < 0.001) and mean CAT score increased by 6.3 units (3.6-9.1, p = 0.001), median symptom count by 4 (2.25, 6, p < 0.001), and mean CRP by 9.0mg/L (2.3-15.8, p = 0.011). Exacerbations where PEFR fell by ≥10% were longer with more symptoms at onset.

Conclusion

Exacerbations of non-CF bronchiectasis are inflammatory events, with worsened symptoms, lung function and health status, and a prolonged recovery period. Symptom diary cards, PEFR and CAT scores are responsive to changes at exacerbation and may be useful tools for their detection and monitoring.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0167-9) contains supplementary material, which is available to authorized users.     

Characterization of Lung Function Impairment in Adults with Bronchiectasis

Background

Characteristics of lung function impairment in bronchiectasis is not fully understood.

Objectives

To determine the factors associated with lung function impairment and to compare changes in spirometry during bronchiectasis exacerbation and convalescence (1 week following 14-day antibiotic therapy).

Methods

We recruited 142 patients with steady-state bronchiectasis, of whom 44 with acute exacerbations in the follow-up were included in subgroup analyses. Baseline measurements consisted of chest high-resolution computed tomography (HRCT), sputum volume, purulence and bacteriology, spirometry and diffusing capacity. Spirometry, but not diffusing capacity, was examined during acute exacerbations and convalescence.

Results

In the final multivariate models, having bronchiectasis symptoms for 10 years or greater (OR = 4.75, 95%CI: 1.46–15.43, P = 0.01), sputum culture positive for Pseudomonas aeruginosa (OR = 4.93, 95%CI: 1.52–15.94, P<0.01) and HRCT total score being 12 or greater (OR = 7.77, 95%CI: 3.21–18.79, P<0.01) were the major variables associated with FEV₁ being 50%pred or less; and the only variable associated with reduced D_LCO was 4 or more bronchiectatic lobes (OR = 5.91, 95%CI: 2.20–17.23, P<0.01). Overall differences in FVC and FEV₁ during exacerbations and convalescence were significant (P<0.05), whereas changes in other spirometric parameters were less notable. This applied even when stratified by the magnitude of FEV₁ and D_LCO reduction at baseline.

Conclusion

Significant lung function impairment should raise alert of chest HRCT abnormality and sputum culture positive for Pseudomonas aeruginosa, in patients with predominantly mild to moderate steady-state bronchiectasis. Acute exacerbations elicited reductions in FVC and FEV₁. Changes of other spirometric parameters were less significant during exacerbations.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01761214","term_id":"NCT01761214"}}NCT01761214     

Serum adiponectin is positively associated with lung function in young adults,independent of obesity: The CARDIA study

Rationale

Adipose tissue produces adiponectin, an anti-inflammatory protein. Adiponectin deficiency in mice is associated with abnormal post-natal alveolar development.

Objective

We hypothesized that lower serum adiponectin concentrations are associated with lower lung function in humans, independent of obesity. We explored mediation of this association by insulin resistance and systemic inflammation.

Methods and Measurements

Spirometry testing was conducted at years 10 and 20 follow-up evaluation visits in 2,056 eligible young adult participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Body mass index, serum adiponectin, serum C-reactive protein (a marker of systemic inflammation), and insulin resistance were assessed at year 15.

Main Results

After controlling for body mass index, years 10 and 20 forced vital capacity (FVC) were 81 ml and 82 ml lower respectively (p = 0.004 and 0.01 respectively) in the lowest vs. highest adiponectin quartiles. Similarly, years 10 and 20 forced expiratory volume in one second (FEV₁) were 50 ml and 38 ml lower (p = 0.01 and 0.09, respectively) in the lowest vs. highest adiponectin quartiles. These associations were no longer significant after adjustment for insulin resistance and C-reactive protein. Serum adiponectin was not associated with FEV₁/FVC or peak FEV₁.

Conclusions

Independent of obesity, lower serum adiponectin concentrations are associated with lower lung function. The attenuation of this association after adjustment for insulin resistance and systemic inflammation suggests that these covariates are on a causal pathway linking adiponectin and lung function.     

A multivariate analysis of serum nutrient levels and lung function

Background

There is mounting evidence that estimates of intakes of a range of dietary nutrients are related to both lung function level and rate of decline, but far less evidence on the relation between lung function and objective measures of serum levels of individual nutrients. The aim of this study was to conduct a comprehensive examination of the independent associations of a wide range of serum markers of nutritional status with lung function, measured as the one-second forced expiratory volume (FEV₁).

Methods

Using data from the Third National Health and Nutrition Examination Survey, a US population-based cross-sectional study, we investigated the relation between 21 serum markers of potentially relevant nutrients and FEV₁, with adjustment for potential confounding factors. Systematic approaches were used to guide the analysis.

Results

In a mutually adjusted model, higher serum levels of antioxidant vitamins (vitamin A, beta-cryptoxanthin, vitamin C, vitamin E), selenium, normalized calcium, chloride, and iron were independently associated with higher levels of FEV₁. Higher concentrations of potassium and sodium were associated with lower FEV₁.

Conclusion

Maintaining higher serum concentrations of dietary antioxidant vitamins and selenium is potentially beneficial to lung health. In addition other novel associations found in this study merit further investigation.     

Correlating changes in lung function with patient outcomes in chronic obstructive pulmonary disease: a pooled analysis

Background

Relationships between improvements in lung function and other clinical outcomes in chronic obstructive pulmonary disease (COPD) are not documented extensively. We examined whether changes in trough forced expiratory volume in 1 second (FEV₁) are correlated with changes in patient-reported outcomes.

Methods

Pooled data from three indacaterol studies (n = 3313) were analysed. Means and responder rates for outcomes including change from baseline in Transition Dyspnoea Index (TDI), St. George''s Respiratory Questionnaire (SGRQ) scores (at 12, 26 and 52 weeks), and COPD exacerbation frequency (rate/year) were tabulated across categories of ΔFEV₁. Also, generalised linear modelling was performed adjusting for covariates such as baseline severity and inhaled corticosteroid use.

Results

With increasing positive ΔFEV₁, TDI and ΔSGRQ improved at all timepoints, exacerbation rate over the study duration declined (P < 0.001). Individual-level correlations were 0.03-0.18, but cohort-level correlations were 0.79-0.95. At 26 weeks, a 100 ml increase in FEV₁ was associated with improved TDI (0.46 units), ΔSGRQ (1.3-1.9 points) and exacerbation rate (12% decrease). Overall, adjustments for baseline covariates had little impact on the relationship between ΔFEV₁ and outcomes.

Conclusions

These results suggest that larger improvements in FEV₁ are likely to be associated with larger patient-reported benefits across a range of clinical outcomes.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00393458","term_id":"NCT00393458"}}NCT00393458, {"type":"clinical-trial","attrs":{"text":"NCT00463567","term_id":"NCT00463567"}}NCT00463567, and {"type":"clinical-trial","attrs":{"text":"NCT00624286","term_id":"NCT00624286"}}NCT00624286     

Apical CFTR Expression in Human Nasal Epithelium Correlates with Lung Disease in Cystic Fibrosis

Introduction

Although most individuals with cystic fibrosis (CF) develop progressive obstructive lung disease, disease severity is highly variable, even for individuals with similar CFTR mutations. Measurements of chloride transport as expression of CFTR function in nasal epithelial cells correlate with pulmonary function and suggest that F508del-CFTR is expressed at the apical membrane. However, an association between quantitative apical CFTR expression in nasal epithelium and CF disease severity is still missing.

Methods and Materials

Nasal epithelial cells from healthy individuals and individuals with CF between 12–18 years were obtained by nasal brushing. Apical CFTR expression was measured by confocal microscopy using CFTR mAb 596. Expression was compared between both groups and expression in CF nasal epithelial cells was associated with standardized pulmonary function (FEV₁%).

Results

The proportion of cells expressing apical CFTR in columnar epithelium is lower in CF compared to non-CF. The apical CFTR expression level was significantly correlated with FEV₁% in F508del homozygous subjects (r = 0.63, p = 0.012).

Conclusion

CFTR expression in nasal epithelial cells is lower in subjects with CF compared to healthy subjects. The proportion of cells expressing F508del-CFTR at the apical membrane is variable between subjects and is positively correlated with FEV₁% in F508del-CFTR homozygous subjects.     

Imbalance of dendritic cell co-stimulation in COPD

Background

Dendritic cells (DCs) control immunity and play a role in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, the expression of function-associated surface molecules on circulating DCs in COPD is unknown.

Methods

Four-colour flow cytometry was used to compare blood DC surface molecules of 54 patients with COPD (median age: 59 years; median FEV₁: 38% predicted, median CAT score: 24) with two age-matched control groups with normal lung function: 21 current smokers and 21 never-smokers.

Results

Concentrations of plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) and the mDC/pDC ratio did not differ between the groups. The increased expression of BDCA-1, BDCA-3, CD86 and CCR5 on mDCs in patients with COPD did not significantly differ from smokers with normal lung function. In contrast, COPD was specifically characterised by a decreased expression of the anti-inflammatory co-stimulatory molecule PD-L1 on pDCs and an increased expression of the pro-inflammatory co-stimulatory molecule OX40 ligand (OX40L) on mDCs. These changes were not confined to patients with elevated systemic inflammation markers (leukocytes, c-reactive protein, interleukin-6, fibrinogen). The ratio of OX40L to PD-L1 expression (OX40L/PD-L1 ratio), a quantitative measure of imbalanced DC co-stimulation, correlated with the severity of pulmonary emphysema in patients with COPD.

Conclusion

An imbalance of DC co-stimulation might contribute to the pathogenesis of COPD.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0174-x) contains supplementary material, which is available to authorized users.