Sputum Biomarkers in Wood and Tobacco Smoke Etiotypes of Chronic Obstructive Pulmonary Disease.

Introduction: There is a need to better understand the etiotypes of chronic obstructive pulmonary disease (COPD) beyond the tobacco-smoke (TS-COPD). Wood smoke COPD (WS-COPD) is characterized by greater airway compromise, milder emphysema, and slower rate of lung function decline than TS-COPD. However, it is unclear if these two etiotypes of COPD have differences in sputum biomarker concentrations. Objective was to compare sputum levels of selected sputum biomarkers between WS-COPD and TS-COPD, and healthy controls. Methods: Eighty-eight women (69±12 years) were recruited and classified into: WS-COPD (n=31), TS-COPD (n=29) and controls (n=28). Using ELISA, we determined induced sputum levels of metalloproteinase 9 (MMP-9), chemokine ligand 5 (CCL5), interleukin-8 (IL-8), chemokine ligand 16 (CCL16/HCC-4) and vascular endothelial growth factor (VEGF-1). Differences were analyzed by Kruskal-Wallis and Mann-Whitney-U tests and correlation between airflow limitation and biomarkers by Spearman's test. Results: At similar degree of airflow obstruction, anthropometrics and medications use, the level of sputum CCL5 was higher in TS-COPD than WS-COPD (p=0.03) without differences in MMP-9, IL-8, CCL16/HCC-4, and VEGF-1. Women with WS-COPD and TS-COPD showed significantly higher sputum levels of MMP-9, IL-8 and CCL5 compared with controls (p<0.001). FEV1% predicted correlated negatively with levels of MMP-9 (rho:-0.26; P=0.016), CCL5 (rho:-0.37; P=0.001), IL-8 (rho:-0.42; P<0.001) and VEGF (rho:-0.22; P=0.04). Conclusion: While sputum concentrations of MMP-9, IL-8, and CCL5 were higher in COPD women compared with controls, women with TS-COPD had higher levels of CCL5 compared with those with WS-COPD. Whether this finding relates to differences in pathobiological pathways remains to be determined.

Study of the Direct Costs of Asthma at a Healthcare Service Provider in Bogotá, Colombia.

OBJECTIVES: This study aimed to describe clinical characteristics and direct medical costs associated with disease treatment in Colombia patients with asthma from 1 healthcare provider. METHODS: This was a descriptive study with a retrospective data collection from a healthcare provider's electronic medical records in Colombia. A clinical, demographic, and healthcare resource utilization profile was developed over a 12-month observation period after the identification of eligible patients. To determine the mean cost per patient per year, the total frequencies of resource utilization were added, and the result was multiplied by the unit cost of each of them. RESULTS: A total of 7919 patients were included in the analysis. The mean ± SD cost per patient per year ranged from $189.5 ± $1.900.6 to $240.2 ± $1.903.6 depending on the price guidebook. The total cost had been driven by the medication use (79% of total cost) and by the outpatient visits (20% of total cost). CONCLUSIONS: In the population analyzed, the mean total direct cost per patient per year of asthma was $189.5 and $240.2, depending on the cost source. Direct medical costs were higher in cases classified as severe and in the adult and elderly population. When comparing the sources of resource utilization, it was found that the mean cost per patient obtained from real-life data is lower than the theoretical cost obtained from the bottom-up method with quantification of resources from experts. It is important to consider limitations related to study design and the evolving landscape of asthma treatments.

Smoke, Biomass Exposure, and COPD Risk in the Primary Care Setting: The PUMA Study.

BACKGROUND: The evidence indicates that risk factors other than smoking are important in the development of COPD. It has been postulated that less traditional risk factors (eg, exposure to coal and/or biomass smoke) may interact with smoking to further increase COPD risk. This analysis evaluated the effect of exposure to biomass and smoking on COPD risk in a primary care setting in Latin America. METHODS: Subjects attending routine primary care visits, ≥40 y old, who were current or former smokers or were exposed to biomass smoke, completed a questionnaire and performed spirometry. COPD was defined as post-bronchodilator FEV1/FVC < 0.70 and the lower limit of normal. Smoking was defined by pack-years (≤ 20, 20-30, or > 30), and biomass exposure was defined as an exposure to coal or wood (for heating, cooking, or both) for ≥ 10 y. RESULTS: One thousand seven hundred forty-three individuals completed the questionnaire, and 1,540 performed spirometry. Irrespective of COPD definition, approximately 40% of COPD subjects reported exposure to biomass versus 30% of those without COPD. A higher proportion of COPD subjects (post-bronchodilator FEV1/FVC < 0.70) than those without COPD smoked > 30 pack-years (66% vs 39%); similar results were found with the lower limit of normal definition. Analysis of exposure to biomass > 10 y plus smoking > 20 pack-years (reference was no exposure) found that tobacco smoking (crude odds ratio [OR] 4.50, 95% CI 2.73-7.41; adjusted OR 3.30, 95% CI 1.93-5.63) and biomass exposure (crude OR 3.66, 95% CI 2.00-6.73; adjusted OR 2.28, 95% CI 1.18-4.41) were risk factors for COPD, with smoking a possible confounder for the association between biomass and COPD (post-bronchodilator FEV1/FVC < 0.70); similar results were found with the lower limit of normal definition. CONCLUSIONS: Subjects with COPD from primary care had a higher exposure to biomass and smoking compared with non-COPD subjects. Smoking and biomass are both risk factors for COPD, but they do not appear to have an additive effect.

Asthma-COPD overlap syndrome (ACOS) in primary care of four Latin America countries: the PUMA study.

BACKGROUND: Asthma-COPD overlap syndrome (ACOS) prevalence varies depending on the studied population and definition criteria. The prevalence and clinical characteristics of ACOS in an at-risk COPD primary care population from Latin America was assessed. METHODS: Patients ≥40 years, current/ex-smokers and/or exposed to biomass, attending routine primary care visits completed a questionnaire and performed spirometry. COPD was defined as post-bronchodilator forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) < 0.70; asthma was defined as either prior asthma diagnosis or wheezing in the last 12 months plus reversibility (increase in post-bronchodilator FEV1 or FVC ≥200 mL and ≥12%); ACOS was defined using a combination of COPD with the two asthma definitions. Exacerbations in the past year among the subgroups were evaluated. RESULTS: One thousand seven hundred forty three individuals completed the questionnaire, 1540 performed acceptable spirometry, 309 had COPD, 231 had prior asthma diagnosis, and 78 asthma by wheezing + reversibility. ACOS prevalence in the total population (by post-bronchodilator FEV1/FVC < 0.70 plus asthma diagnosis) was 5.3 and 2.3% by post-bronchodilator FEV1/FVC < 0.70 plus wheezing + reversibility. In the obstructive population (asthma or COPD), prevalence rises to 17.9 and 9.9% by each definition, and to 26.5 and 11.3% in the COPD population. ACOS patients defined by post-bronchodilator FEV1/FVC < 0.7 plus wheezing + reversibility had the lowest lung function measurements. Exacerbations for ACOS showed a prevalence ratio of 2.68 and 2.20 (crude and adjusted, p < 0.05, respectively) (reference COPD). CONCLUSIONS: ACOS prevalence in primary care varied according to definition used. ACOS by post-bronchodilator FEV1/FVC < 0.7 plus wheezing + reversibility represents a clinical phenotype with more frequent exacerbations, which is probably associated with a different management approach.

Exacerbations and health care resource utilization in patients with airflow limitation diseases attending a primary care setting: the PUMA study.

BACKGROUND: COPD, asthma, and asthma-COPD overlap increase health care resource consumption, predominantly because of hospitalization for exacerbations and also increased visits to general practitioners (GPs) or specialists. Little information is available regarding this in the primary care setting. OBJECTIVES: To describe the prevalence and number of GP and specialist visits for any cause or due to exacerbations in patients with COPD, asthma, and asthma-COPD overlap. METHODS: COPD was defined as post-bronchodilator forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) ratio <0.70; asthma was defined as prior medical diagnosis, wheezing in the last 12 months, or wheezing plus reversibility (post-bronchodilator FEV1 or FVC increase ≥200 mL and ≥12%); asthma-COPD overlap was defined as post-bronchodilator FEV1/FVC <0.70 plus prior asthma diagnosis. Health care utilization was evaluated as GP and/or specialist visits in the previous year. RESULTS: Among the 1,743 individuals who completed the questionnaire, 1,540 performed acceptable spirometry. COPD patients had a higher prevalence of any medical visits to any physician versus those without COPD (37.2% vs 21.8%, respectively) and exacerbations doubled the number of visits. The prevalence of any medical visits to any physician was also higher in asthma patients versus those without asthma (wheezing: 47.2% vs 22.7%; medical diagnosis: 54.6% vs 21.6%; wheezing plus reversibility: 46.2% vs 23.8%, respectively). Asthma patients with exacerbations had twice the number of visits versus those without an exacerbation. The number of visits was higher (2.8 times) in asthma-COPD overlap, asthma (1.9 times), or COPD (1.4 times) patients versus those without these respiratory diseases; the number of visits due to exacerbation was also higher (4.9 times) in asthma-COPD overlap, asthma (3.5 times), and COPD (3.8 times) patients. CONCLUSION: COPD, asthma, and asthma-COPD overlap increase the prevalence of medical visits and, therefore, health care resource utilization. Attempts to reduce health care resource use in these patients require interventions aimed at preventing exacerbations.