Tomosynthesis in pulmonary cystic fibrosis with comparison to radiography and computed tomography: a pictorial review

The purpose of this pictorial review is to illustrate chest imaging findings of cystic fibrosis (CF) using tomosynthesis (digital tomography), in comparison to radiography and computed tomography (CT). CF is a chronic systemic disease where imaging has long been used for monitoring chest status. CT exposes the patient to a substantially higher radiation dose than radiography, rendering it unsuitable for the often needed repeated examinations of these patients. Tomosynthesis has recently appeared as an interesting low dose alternative to CT, with an effective dose of approximately 0.08 mSv for children and 0.12 mSv for adults. Tomosynthesis is performed on the same X-ray system as radiography, adding only about 1 min to the normal examination time. Typical pulmonary changes in CF such as mucus plugging, bronchial wall thickening, and bronchiectases are shown in significantly better detail with tomosynthesis than with traditional radiography. In addition, the cost for a tomosynthesis examination is low compared to CT. To reduce the radiation burden of patients with CF it is important to consider low dose alternatives to CT, especially in the paediatric population. Tomosynthesis has a lower radiation dose than CT and gives a superior visualisation of pulmonary CF changes compared to radiography. It is important to further determine the role of tomosynthesis for monitoring disease progression in CF

Systematic review with meta-analysis of the epidemiological evidence relating smoking to COPD, chronic bronchitis and emphysema

<p>Abstract</p> <p>Background</p> <p>Smoking is a known cause of the outcomes COPD, chronic bronchitis (CB) and emphysema, but no previous systematic review exists. We summarize evidence for various smoking indices.</p> <p>Methods</p> <p>Based on MEDLINE searches and other sources we obtained papers published to 2006 describing epidemiological studies relating incidence or prevalence of these outcomes to smoking. Studies in children or adolescents, or in populations at high respiratory disease risk or with co-existing diseases were excluded. Study-specific data were extracted on design, exposures and outcomes considered, and confounder adjustment. For each outcome RRs/ORs and 95% CIs were extracted for ever, current and ex smoking and various dose response indices, and meta-analyses and meta-regressions conducted to determine how relationships were modified by various study and RR characteristics.</p> <p>Results</p> <p>Of 218 studies identified, 133 provide data for COPD, 101 for CB and 28 for emphysema. RR estimates are markedly heterogeneous. Based on random-effects meta-analyses of most-adjusted RR/ORs, estimates are elevated for ever smoking (COPD 2.89, CI 2.63-3.17, n = 129 RRs; CB 2.69, 2.50-2.90, n = 114; emphysema 4.51, 3.38-6.02, n = 28), current smoking (COPD 3.51, 3.08-3.99; CB 3.41, 3.13-3.72; emphysema 4.87, 2.83-8.41) and ex smoking (COPD 2.35, 2.11-2.63; CB 1.63, 1.50-1.78; emphysema 3.52, 2.51-4.94). For COPD, RRs are higher for males, for studies conducted in North America, for cigarette smoking rather than any product smoking, and where the unexposed base is never smoking any product, and are markedly lower when asthma is included in the COPD definition. Variations by sex, continent, smoking product and unexposed group are in the same direction for CB, but less clearly demonstrated. For all outcomes RRs are higher when based on mortality, and for COPD are markedly lower when based on lung function. For all outcomes, risk increases with amount smoked and pack-years. Limited data show risk decreases with increasing starting age for COPD and CB and with increasing quitting duration for COPD. No clear relationship is seen with duration of smoking.</p> <p>Conclusions</p> <p>The results confirm and quantify the causal relationships with smoking.</p

Systematic review of the evidence relating FEV1 decline to giving up smoking

<p>Abstract</p> <p>Background</p> <p>The rate of forced expiratory volume in 1 second (FEV₁) decline ("beta") is a marker of chronic obstructive pulmonary disease risk. The reduction in beta after quitting smoking is an upper limit for the reduction achievable from switching to novel nicotine delivery products. We review available evidence to estimate this reduction and quantify the relationship of smoking to beta.</p> <p>Methods</p> <p>Studies were identified, in healthy individuals or patients with respiratory disease, that provided data on beta over at least 2 years of follow-up, separately for those who gave up smoking and other smoking groups. Publications to June 2010 were considered. Independent beta estimates were derived for four main smoking groups: never smokers, ex-smokers (before baseline), quitters (during follow-up) and continuing smokers. Unweighted and inverse variance-weighted regression analyses compared betas in the smoking groups, and in continuing smokers by amount smoked, and estimated whether beta or beta differences between smoking groups varied by age, sex and other factors.</p> <p>Results</p> <p>Forty-seven studies had relevant data, 28 for both sexes and 19 for males. Sixteen studies started before 1970. Mean follow-up was 11 years. On the basis of weighted analysis of 303 betas for the four smoking groups, never smokers had a beta 10.8 mL/yr (95% confidence interval (CI), 8.9 to 12.8) less than continuing smokers. Betas for ex-smokers were 12.4 mL/yr (95% CI, 10.1 to 14.7) less than for continuing smokers, and for quitters, 8.5 mL/yr (95% CI, 5.6 to 11.4) less. These betas were similar to that for never smokers. In continuing smokers, beta increased 0.33 mL/yr per cigarette/day. Beta differences between continuing smokers and those who gave up were greater in patients with respiratory disease or with reduced baseline lung function, but were not clearly related to age or sex.</p> <p>Conclusion</p> <p>The available data have numerous limitations, but clearly show that continuing smokers have a beta that is dose-related and over 10 mL/yr greater than in never smokers, ex-smokers or quitters. The greater decline in those with respiratory disease or reduced lung function is consistent with some smokers having a more rapid rate of FEV₁decline. These results help in designing studies comparing continuing smokers of conventional cigarettes and switchers to novel products.</p

Occupational exposure to vapor, gas, dust, or fumes and chronic airflow limitation, COPD, and emphysema: the Swedish CArdioPulmonary BioImage Study (SCAPIS pilot)

Kjell Tor&eacute;n,1 Jenny Vikgren,2 Anna-Carin Olin,1 Annika Rosengren,3 G&ouml;ran Bergstr&ouml;m,3 John Brandberg2 1Section of Occupational and Environmental Medicine, Institute of Medicine, Sahlgrenska Academy, 2Department of Radiology, Institute of Clinical Sciences, 3Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden Background: The aim of this study was to estimate the occupational burden of airflow limitation, chronic airflow limitation, COPD, and emphysema.Materials and methods: Subjects aged 50&ndash;64 years (n=1,050) were investigated with forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC). Airflow limitation was defined as FEV1/FVC &lt;0.7 before bronchodilation. Chronic airflow limitation was defined after bronchodilation either according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) as FEV1/FVC &lt;0.7 or according to the lower limit of normal (LLN) approach as FEV1/FVC &lt; LLN. COPD was defined as chronic airflow limitation (GOLD) in combination with dyspnea, wheezing, or chronic bronchitis. Emphysema was classified according to findings from computed tomography of the lungs. Occupational exposure was defined as self-reported occupational exposure to vapor, gas, dust, or fumes (VGDF). Odds ratios (OR) were calculated in models adjusted for age, gender, and smoking; population-attributable fractions and 95% CI were also calculated.Results: There were significant associations between occupational exposure to VGDF and COPD (OR 2.7, 95% CI 1.4&ndash;51), airflow limitation (OR 1.8, 95% CI 1.3&ndash;2.5), and emphysema (OR 1.8, 95% CI 1.1&ndash;3.1). The associations between occupational exposure to VGDF and chronic airflow limitation were weaker, and for the OR, the CIs included unity. The population-attributable fraction for occupational exposure to VGDF was 0.37 (95% CI 0.23&ndash;0.47) for COPD and 0.23 (95% CI 0.05&ndash;0.35) for emphysema.Conclusion: The occupational burden of COPD and computed tomography&ndash;verified emphysema is substantial. Keywords: work, occupation, obstructive airways disease, epidemiology, computed tomograph

The Association Between Occupational Exposure To Vapor, Gas, Dust And Fume And Different Definitions Of COPD, Emphysema And Chronic Bronchitis: The Swedish Cardiopulmonary Bioimage Study (scapis)

Objectives: To elucidate whether different spirometric definitions of chronic obstructive pulmonary disease (COPD) affect the risk estimates of tobacco smoking or occupational exposures, to investigate the relation between occupational exposure and CT-confirmed emphysema and the risk of chronic bronchitis Methods: 1,050 subjects aged 50 to 64 years were investigated with forced expiratory volume in one second (FEV ), (forced vital capacity) FVC and 1 slow vital capacity (SVC) before and 15 minutes after inhalation 400 µg of salbutamol. COPD was defined as the ratio FEV /VC&lt;0.7 PREDIL 1 using the maximum value of FVC or SVC before bronchodilation, and COPD as the ratio FEV /VC&lt;0.7 using the maximum value of GOLD 1 FVC or SVC after bronchodilation. COPD was defined as the ratio FEV /VC below LLN using the maximum value of FVC or SVC. LLN 1 Emphysema was classified according to CT findings, and all subjects with at least mild emphysema in any zone of the lung were categorized as having emphysema. Occupational exposure was defined as an affirmative answer to items about occupational exposure to vapor, gas, dust and fume, with addition of items about occupational exposure to welding fumes or diesel exhausts. Odds ratios were calculated in models adjusted for age, gender and smoking habits. Results: The risks of occupational exposures were quite similar regardless of whether COPD or COPD definition was applied. COPD GOLD LLN PREDIL showed higher and statistically significant increased risks of the different classifications of occupational exposures. Occupational exposures were associated with an increased risk for chronic bronchitis, among men and women and among “never smokers” as well as among “ever-smokers”. When stratified for gender, occupational exposure among men was significantly associated with emphysema (OR 2.0, 95% CI 1.04-3.9). There was no association among women. Current smoking was strongly associated with emphysema, OR 15.3 (95% CI 6.1-38.9), but also[MR5] with former smoking OR 3.1 (95% CI 1.2-7.8). For COPD and COPD the risk related to current smoking GOLD LLN were similar regardless the definition. Conclusions The risks of COPD in relation to smoking or occupational exposures were quite similar regardless the definitions used. Occupational exposures were associated with a doubled risk for CT-verified emphysema, especially among men. Occupational exposures were associated with a doubled risk for chronic bronchitis, especially among “never-smokers”

The Association Between Occupational Exposure To Vapor, Gas, Dust And Fume And Different Definitions Of COPD, Emphysema And Chronic Bronchitis: The Swedish Cardiopulmonary Bioimage Study (scapis)

Objectives: To elucidate whether different spirometric definitions of chronic obstructive pulmonary disease (COPD) affect the risk estimates of tobacco smoking or occupational exposures, to investigate the relation between occupational exposure and CT-confirmed emphysema and the risk of chronic bronchitis Methods: 1,050 subjects aged 50 to 64 years were investigated with forced expiratory volume in one second (FEV ), (forced vital capacity) FVC and 1 slow vital capacity (SVC) before and 15 minutes after inhalation 400 μg of salbutamol. COPD was defined as the ratio FEV /VC&lt;0.7 PREDIL 1 using the maximum value of FVC or SVC before bronchodilation, and COPD as the ratio FEV /VC&lt;0.7 using the maximum value of GOLD 1 FVC or SVC after bronchodilation. COPD was defined as the ratio FEV /VC below LLN using the maximum value of FVC or SVC. LLN 1 Emphysema was classified according to CT findings, and all subjects with at least mild emphysema in any zone of the lung were categorized as having emphysema. Occupational exposure was defined as an affirmative answer to items about occupational exposure to vapor, gas, dust and fume, with addition of items about occupational exposure to welding fumes or diesel exhausts. Odds ratios were calculated in models adjusted for age, gender and smoking habits. Results: The risks of occupational exposures were quite similar regardless of whether COPD or COPD definition was applied. COPD GOLD LLN PREDIL showed higher and statistically significant increased risks of the different classifications of occupational exposures. Occupational exposures were associated with an increased risk for chronic bronchitis, among men and women and among “never smokers” as well as among “ever-smokers”. When stratified for gender, occupational exposure among men was significantly associated with emphysema (OR 2.0, 95% CI 1.04-3.9). There was no association among women. Current smoking was strongly associated with emphysema, OR 15.3 (95% CI 6.1-38.9), but also[MR5] with former smoking OR 3.1 (95% CI 1.2-7.8). For COPD and COPD the risk related to current smoking GOLD LLN were similar regardless the definition. Conclusions The risks of COPD in relation to smoking or occupational exposures were quite similar regardless the definitions used. Occupational exposures were associated with a doubled risk for CT-verified emphysema, especially among men. Occupational exposures were associated with a doubled risk for chronic bronchitis, especially among “never-smokers”

Measures of bronchodilator response of FEV1, FVC and SVC in a Swedish general population sample aged 50&ndash;64 years, the SCAPIS Pilot Study

K Tor&eacute;n,1 B Bake,1 A-C Olin,1 G Engstr&ouml;m,2 A Blomberg,3 J Vikgren,4 J Hedner,5 J Brandberg,4 HL Persson,6,7 CM Sk&ouml;ld,8 A Rosengren,9 G Bergstr&ouml;m,9 C Janson10 1Section of Occupational and Environmental Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, 2Department of Clinical Science, Lund University, Malm&ouml;, 3Division of Medicine/Respiratory Medicine, Department of Public Health and Clinical Medicine, Ume&aring; University, Ume&aring;, 4Department of Radiology, Institute of Clinical Sciences, 5Department of Internal Medicine/Lung Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, 6Department of Respiratory Medicine, 7Department of Medicine and Health Sciences, Link&ouml;ping University, Link&ouml;ping, 8Respiratory Medicine Unit, Department of Medicine Solna, Centre for Molecular Medicine, Karolinska Institutet, Stockholm, 9Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, 10Department of Medical Sciences, Clinical Physiology and Lung, Allergy and Sleep Research, Uppsala University, Uppsala, Sweden Background: Data are lacking from general population studies on how to define changes in lung function after bronchodilation. This study aimed to analyze different measures of bronchodilator response of forced expiratory volume in 1&nbsp;second (FEV1), forced vital capacity (FVC) and slow vital capacity (SVC). Materials and methods: Data were derived from the Swedish Cardiopulmonary Bioimage Study (SCAPIS) Pilot study. This analysis comprised 1,050 participants aged 50&ndash;64&nbsp;years from the general population. Participants were investigated using a questionnaire, and FEV1, FVC and SVC were recorded before and 15&nbsp;minutes after inhalation of 400&nbsp;&micro;g of salbutamol. A bronchodilator response was defined as the relative change from baseline value expressed as the difference in units of percent predicted normal. Predictors of bronchodilator responses were assessed using multiple linear regression models. Airway obstruction was defined as FEV1/FVC ratio below lower limit of normal (LLN) before bronchodilation, and COPD was defined as an FEV1/FVC ratio below LLN after bronchodilation. Physician-diagnosed asthma was defined as an affirmative answer to &ldquo;Have you ever had asthma diagnosed by a physician?&rdquo;. Asymptomatic never-smokers were defined as those not reporting physician-diagnosed asthma, physician-diagnosed COPD or emphysema, current wheeze or chronic bronchitis and being a lifelong never-smoker.Results: Among all subjects, the greatest bronchodilator responses (FEV1, FVC and SVC) were found in subjects with asthma or COPD. The upper 95th percentile of bronchodilator responses in asymptomatic never-smokers was 8.7% for FEV1, 4.2% for FVC and 5.0% for SVC. The bronchodilator responses were similar between men and women. In a multiple linear regression model comprising all asymptomatic never-smokers, the bronchodilator response of FEV1 was significantly associated with airway obstruction and height. Conclusion: When the bronchodilator response in asymptomatic never-smokers is reported as the difference in units of predicted normal, significant reversibility of FEV1, FVC and SVC to bronchodilators is ~9%, 4% and 5%, respectively. Keywords: spirometry, reversibility, COPD, epidemiolog