Blood eosinophil cationic protein and eosinophil-derived neurotoxin are associated with different asthma expression and evolution in adults.

BACKGROUND: Eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP) are proteins released by activated eosinophils whose role in adult asthma remains unclear. OBJECTIVE: To study associations between ECP, EDN and various asthma characteristics in adults from the Epidemiological Study on the Genetics and Environment of Asthma (EGEA). METHODS: Plasma ECP and EDN levels were measured by ELISA. Cross-sectional analyses were performed in 941 adults (43±16 years old, 39% with asthma) at EGEA2 (2003-2007). Longitudinal analyses investigated the associations between EDN level at EGEA2 and changes in asthma characteristics between EGEA2 and EGEA3 (2011-2013, n=817). We used generalised estimated equations adjusted for age, sex, smoking status and body mass index to take into account familial dependence. RESULTS: At EGEA2, both high ECP and EDN levels were associated with current asthma (adjusted OR (aOR) (95% CI): 1.69 (1.35-2.12) and 2.12 (1.76-2.57)). Among asthmatics, high EDN level was associated with asthma attacks (aOR: 1.50 (1.13-1.99)), wheezing and breathlessness (aOR: 1.38 (1.05-1.80)), use of asthma treatments (aOR: 1.91 (1.37-2.68)) and bronchial hyper-responsiveness (aOR: 2.03 (1.38-2.97)), even after further adjustment on ECP. High ECP level was associated with high neutrophil count and tended to be associated with chronic bronchitis. High EDN level at EGEA2 was associated with persistent asthma (aOR: 1.62 (1.04-2.52)), nocturnal symptoms (aOR from 2.19 to 3.57), worsening wheezing and breathlessness (aOR: 1.97 (1.36-2.85)) and nocturnal shortness of breath (aOR: 1.44 (1.04-1.98)) between EGEA2 and EGEA3. CONCLUSIONS: EDN and ECP were associated with different asthma expression in adults. EDN could be a potential biomarker to monitor asthma evolution in adults.

Asthma prevalence and associated factors among lebanese adults: the first national survey.

BACKGROUND: No national research has yet explored the prevalence of asthma among adults in Lebanon. This study aims to evaluate the prevalence of physician-diagnosed asthma and current asthma, and their determinants among Lebanese adults 16 years old or above. METHODS: A cross-sectional study was carried out using a multistage cluster sampling. The questionnaire used collected information on asthma, respiratory symptoms, and risk factors. RESULTS: The prevalence of physician-diagnosed asthma was 6.7% (95% CI 5-8.7%), and that of current asthma was 5% (95% CI 3.6-6.9%). Chronic symptoms such as cough, wheezing, and shortness of breath were worst at night. Factors positively associated with physician-diagnosed asthma were a secondary educational level (adjusted OR, aOR = 4.45), a family history of chronic respiratory diseases (aOR = 2.78), lung problems during childhood (15.9), and allergic rhinitis (4.19). Additionally, consuming fruits and vegetables less than once per week (3.36), a family history of chronic respiratory diseases (3.92), lung problems during childhood (9.43), and allergic rhinitis (8.12) were positively associated with current asthma. CONCLUSIONS: The prevalence of asthma was within the range reported from surrounding countries. However, repeated cross-sectional studies are necessary to evaluate trends in asthma prevalence in the Lebanese population.

High level of fluorescent oxidation products and worsening of asthma control over time.

High Fluorescent oxidation products level (FlOPs), a global oxidative stress biomarker, was associated cross-sectionally with poor asthma outcomes but its longitudinal association with asthma evolution has never been examined. We aimed to study the associations between FlOPs level at baseline and changes in current asthma, asthma attacks and asthma control status over 8 years. We used data from the second survey of the French EGEA cohort study as baseline and the third survey as follow-up. At baseline, the mean age of the 489 participants with ever asthma was 39 (± 16) years, 49% were women. Among participants with controlled asthma at baseline, high FlOPs level was significantly associated with worsening of asthma control at follow-up (odds-ratio adjusted for age, sex and smoking status (95% CI): 2.27 (1.32-3.90). No other significant associations were observed. In conclusion, results suggest FlOPs as a predictor of asthma evolution in adults and a good candidate marker in asthma management.

Validation of the St George's respiratory questionnaire and risks factors affecting the quality of life of Lebanese COPD and asthma patients.

Objective: We aimed to validate the Arabic version of the St George's Respiratory Questionnaire (SGRQ) for use in Lebanese Chronic obstructive pulmonary disease (COPD) and asthma patients and to identify risk factors that might affect the quality of life in these patients. Methods: COPD (n = 90) and asthma patients (n = 124) were recruited from the outpatient clinics of the Pulmonology department of a university hospital and a medical center in Beirut. They filled out a standardized questionnaire. The total SGRQ score and the component scores (symptoms, activity and impacts) were calculated. To confirm the SGRQ validity in the Lebanese population, factor analyses were applied for the whole sample, only asthma and only COPD patients, respectively. The associations between the total SGRQ score and FEV1% predicted, CCQ score and MRC scale were assessed. Multiple linear regression models were used to evaluate the association between the total SGRQ scores and the socio-demographics and the diseases risk factors. Results: COPD patients had a higher SGRQ total and subscales scores compared to asthma patients. A high Cronbach's alpha was found for the whole sample (0.802), only COPD patients (0.833) and only asthma patients (0.734). A significant negative correlation was found between FEV1% predicted and the total SGRQ scores. Occupational exposure, BMI and previous waterpipe smoking were among the factors that significantly and positively influenced a higher SGRQ score. Conclusions: The Lebanese version of the SGRQ emerges as a good health-related quality of life evaluative instrument that is reasonable to be used in COPD and asthma patients in Lebanon.

Structure and evaluation of a residency research program in a university hospital.

BACKGROUND: Most academic medical institutions lack a structured program that provides residents with an in-depth research training. The objectives of this paper are to describe a comprehensive residency research program at a university hospital, and to assess the pre- post-self-assessment of research capabilities of resident for the evaluation of the program. METHODS: The residency research program (RRP) was implemented in 2011 as an essential component of the residency program at the American University of Beirut Medical Center. Categorical residents are required to carry out a research project and go through all the steps of the research process from identifying a topic to writing a manuscript. As for evaluating the program, data were collected from residents who graduated between 2014 and 2016 using a questionnaire, which included the overall evaluation of the program, self-assessment on research-related tasks pre- and post- joining the program, as well as general recommendations. The mean scores on the five-point Likert scale were transformed into percentages (0-100%). The average was calculated and the difference in the means was reported. RESULTS: Overall, 103 residents from the different clinical departments were included in this study. Residents' self-assessment showed a 19.3% improvement in research-related tasks before and after completion of the RRP (P < 0.0001). Most of the residents have either published or are in the process of publishing their projects (34 and 55.3%, respectively). Time management was the most reported challenge. Generally, the program was evaluated positively. CONCLUSION: The RRP is a unique, well-structured program, encompassing residents from various clinical departments, which enhances residents' research capabilities.

Surfactant protein D multimerization and gene polymorphism in COPD and asthma.

BACKGROUND AND OBJECTIVE: A structural single nucleotide polymorphism rs721917 in the surfactant protein D (SP-D) gene, known as Met11Thr, was reported to influence the circulating levels and degree of multimerization of SP-D and was associated with both COPD and atopy in asthma. Moreover, disease-related processes are known to degrade multimerized SP-D, however, the degree of the protein degradation in these diseases is not clarified. We aimed to determine the distribution of multimerized (high molecular weight (HMW)) and non-multimerized (low molecular weight (LMW)) species of serum SP-D and their correlation with genetic polymorphisms and presence of disease in Lebanese COPD and asthmatic patients. METHODS: Serum SP-D levels were measured by ELISA in 88 COPD, 121 asthmatic patients and 223 controls. Randomly selected subjects were chosen for genotyping of rs721917 and multimerization studies. HMW and LMW SP-D were separated by gel permeation chromatography. RESULTS: Serum SP-D levels were significantly increased in patients with COPD, but not in asthmatic patients, when compared to controls. Met11Thr variation strongly affected serum SP-D levels and the degree of multimerization, but was not associated with COPD and asthma in the study. Remarkably, HMW/LMW serum SP-D ratio was significantly lower in Met11/Met11 COPD and asthmatic patients compared to controls. CONCLUSION: Collectively, non-multimerized species of serum SP-D were dominant in COPD and asthmatic patients suggesting that degradation of SP-D takes place to a significant degree in pulmonary disease. Assays that can separate SP-D proteolytic breakdown products or modified forms from naturally occurring SP-D trimers may result in optimal disease markers for pulmonary inflammatory diseases.

Oxidative stress biomarkers and asthma characteristics in adults of the EGEA study.

Asthma is an oxidative stress related disease, but associations with asthma outcomes are poorly studied in adults. We aimed to study the associations between several biomarkers related to oxidative stress and various asthma outcomes.Cross-sectional analyses were conducted in 1388 adults (mean age 43 years, 44% with asthma) from the Epidemiological Study of the Genetics and Environment of Asthma (EGEA2). Three blood antioxidant enzyme activities (biomarkers of response to oxidative stress) and exhaled breath condensate 8-isoprostanes and plasma fluorescent oxidation products (FlOPs) levels (two biomarkers of damage) were measured. Associations between biomarkers and 1) ever asthma and 2) asthma attacks, asthma control and lung function in participants with asthma were evaluated using regression models adjusted for age, sex and smoking.Biomarkers of response were unrelated to asthma outcomes. Higher 8-isoprostane levels were significantly associated with ever asthma (odds ratio for one interquartile range increase 1.28 (95% CI 1.06-1.67). Among participants with asthma, 8-isoprostane levels were negatively associated with adult-onset asthma (0.63, 0.41-0.97) and FlOPs levels were positively associated with asthma attacks (1.33, 1.07-1.65), poor asthma control (1.30, 1.02-1.66) and poor lung function (1.34, 1.04-1.74).Our results suggest that 8-isoprostanes are involved in childhood-onset asthma and FlOPs are linked to asthma expression.

The impact of COVID-19 on the mental health of Lebanese pharmacists: A national cross-sectional study.

Introduction: The COVID-19 pandemic has induced a global mental health crisis with variable consequences. This study aimed to assess the psychological impact of COVID-19 regarding anxiety, insomnia, depression, and response to trauma on pharmacists in Lebanon during COVID-19, and to identify factors contributing to psychological distress. Methods: This was a cross-sectional study among pharmacists that involved the use of the 7-item Generalized Anxiety Disorder (GAD-7), 7-item Insomnia Severity Index (ISI), Patient Health Questionnaire 9-item depression module (PHQ-9), and Impact of Event Scale revised (IES-R) subscales. Descriptive statistical analyses were performed to determine the study distribution. The associations between the scores and the participants' characteristics were assessed using the Chi-square test. Four binary logistic regression models were used to evaluate the association between the scores and the potential confounders, followed by four multivariable logistic regressions. An alpha of 0.05 was used to determine statistical significance. Results: Participants comprised 311 pharmacists from all Lebanese districts, of whom 251 (80.7%) were females and 181 (58.2%) aged between 26 and 35 years. The majority of the participants were community pharmacists (n = 178, 57.2%). A considerable proportion of participants had symptoms of anxiety (n = 128, 41.2%), insomnia (n = 64, 20.6%), depression (n = 157, 50.5%), and subjective stress (n = 227, 78.8%). Higher anxiety (aOR: 1.73, 95% CI: 1.08; 2.78, p-value: 0.02), higher depression (aOR: 3.06, 95% CI: 1.73; 5.39, p-value: 0.001), and higher stress (aOR: 1.86, 95 percent CI: 1.11; 3.14, p-value: 0.02) scores were significantly associated with pharmacists who reported that their work involves contact with infected/suspected COVID-19 patients. Interestingly, pharmacists who expressed concern about contracting COVID-19 infection had significantly higher anxiety (aOR: 2.35, 95% CI: 1.40; 3.94, p-value: 0.001) and higher depression scores (aOR: 2.64, 95% CI: 1.49; 4.67, p-value: 0.001) respectively. Conclusion: The preliminary results from pharmacists in Lebanon reflect increase in stress, burden, and frustration felt by pharmacists, creating a negative impact on their mental health and well-being during the global pandemic. As frontline healthcare workers, the role of pharmacists in the community should not be overlooked, and their mental health should be well investigated.

Knowledge, attitude, and practice of patients with diabetes towards diabetic nephropathy, neuropathy and retinopathy.

Background: Epidemiological and knowledge, attitude and practice (KAP) studies about diabetic microvascular complications are lacking. The goals of this study are: determining 1) the prevalence of diabetes mellitus subtypes and microvascular complications, 2) the KAP towards the complications and 3) health-seeking behavior, barriers to follow-up, stigma and sources of information. Methods: A cross-sectional study was conducted from January to October 2020 enrolling 380 Lebanese patients with diabetes asked about socio-demographic and lifestyle characteristics, medical, therapeutic, supplement, and dietary history, KAP scores, health-seeking behavior, stigma, barriers to compliance, and sources of information. Results: The prevalence of diabetes type II, type I, gestational, and the microvascular complications was 82.23%, 15.65%, 2.12%, and 33.07% respectively. Factors with significant association were: 1) good quality of life (ß=-0.03; p=0.005) and presence of microvascular complications (ß=3.58; p=0.001) with knowledge score, 2) good quality of life (ß=-0.01; p=0.02) and absence of the complications (ß=-0.33; p=0.001) with attitude score, 3) advanced age (ß=0.01; p=0.01), no metformin (ß=-0.39; p=0.005), and low-protein diet (ß=0.6; p=0.02) with practice score. Patients visited community pharmacies (41.84%) and clinics (46.32%). Barriers were costs (33.42%) and time (30.53%). Few talked about the complications to the family (19.74%). Sources of information were healthcare workers. Conclusion: Awareness campaigns should be tailored accordingly to retard the microvascular complications.

Pharmacy Students' Mental Health and Resilience in COVID-19: An Assessment after One Year of Online Education.

COVID-19 has impacted mental health and affected education due to the shift to remote learning. The purpose of the current study was to assess the mental health of pharmacy students one year following the onset of the pandemic. A descriptive cross-sectional questionnaire was distributed to pharmacy students. The severity of depression, anxiety, and stress was assessed by the Depression Anxiety Stress Scale (DASS-21), and resilience was assessed by the Brief Resilience Scale (BRS). COVID-19-related economic, educational, and health stressors, and students' vaccine attitudes were surveyed. Descriptive, bivariate, and multivariable analysis were used, and a p-value of <0.05 was considered significant. A total of 561 students participated; 37% had mild-to-moderate depression, 37% had severe-to-extremely-severe anxiety, and 52% demonstrated normal stress levels. Severe depression, anxiety, and stress were associated with smoking and feeling isolated due to COVID-19. Around 40% of students had low resilience, associated with smoking, being in the third or fourth year of pharmacy study, and the consumption of caffeinated beverages. The mean score of satisfaction with online learning was 60.3 ± 21.3%. Only 5% of participants were vaccinated, of which 87% trusted the benefits of vaccines and their role in controlling the pandemic. One year after the onset of COVID-19, depression, anxiety, stress, and low resilience were observed among pharmacy students; the investigation of the long-term mental effects of the pandemic on university students is warranted.

Fever among preschool-aged children: a cross-sectional study assessing Lebanese parents' knowledge, attitudes and practices regarding paediatric fever assessment and management.

OBJECTIVES: This study investigated parental knowledge, attitudes and practices towards fever in preschool children to help address gaps in public health and provide information with the aim of supporting clinical reports for parental education. DESIGN: A cross-sectional study design was used to explore parental experiences with fever. SETTING: Participants were recruited randomly from schools all over Lebanon targeting the preschool divisions. PARTICIPANTS: Parents of children aged 5 years or less. INTERVENTIONS: An electronic self-administered questionnaire was sent to the parents through the schools' emails and e-learning mobile applications. PRIMARY AND SECONDARY OUTCOMES: The primary outcome measure was to assess parental knowledge about the precise definition of fever, correct use of medications and to evaluate the impact of sociodemographic factors on this knowledge. The secondary outcome measures were to assess parental attitudes and practices of fever management, sources of information and reasons to seek primary medical attention. RESULTS: A total of 733 parents were included in the study. Only 44% identified fever correctly according to the recognised definition by international guidelines. A significant association between parents' knowledge of antibiotics and years of parenting experience was found (adjusted OR, ORa=4.23, 95% CI 1.41 to 12.68, p=0.01). Other sociodemographic factors that were significantly associated with parents' knowledge of antibiotics were age (ORa=3.42, 95% CI 1.09 to 10.73, p=0.036) and education level (ORa=7.99, 95% CI 3.71 to 17.23, p<0.001). Greater than 75% usually give their children antipyretics without consulting a doctor. Approximately one-quarter of parents (26.3%) consulted different doctors at the same time, of which more than half (58.4%) had received different medical information. CONCLUSIONS: This research determines deficiencies in parents' knowledge of fever with some malpractices in its management particularly regarding antipyretic use. It provides insight for healthcare providers to empower parental experiences by offering the necessary information to enhance general outcomes of febrile sickness.

The role of pharmacists in providing immunization to the general population: Are Lebanese pharmacists ready for this role?

Background: Vaccination rates remain suboptimal in multiple areas around the world in spite of evidence that immunization is one of the most effective interventions for precluding morbidity and mortality. Non-traditional vaccine providers are proposed to augment immunization coverage. Pharmacists can have multiple vital roles to educate, facilitate and immunize against vaccine-preventable diseases. Limited data are available around the expertise and practices of Lebanese pharmacists in providing immunization services. Objective: This study aimed to determine predictors that are associated with vaccine administration by pharmacists in Lebanon, and to assess experiences and practices in providing immunization. Methods: This is a cross-sectional study that included pharmacists from all over Lebanon. A web-based self-administered validated questionnaire was adapted with permission. A snowball sampling technique was used to collect data through an electronic self-administered questionnaire between March and June 2021. The web-link to the survey was also shared by the Order of Pharmacists of Lebanon with all registered pharmacists to gather a sample from different districts all over Lebanon. Results: A total of 315 pharmacists were included. A significant positive association was found between completion of an immunization training program (ORa = 2.085, [95%CI 1.006:4.322], P = 0.048), full-time pharmacists (ORa = 2.504, [95%CI 1.156:5.426], P = 0.02), 1 to 4 years of practice experience (ORa = 3.855, [95%CI 1.849:8.039], P < 0.0001), geographic area of practice (ORa = 3.201, [95%CI 1.242:8.249], P = 0.016; ORa = 5.373, [95%CI 1.859:15.530], P = 0.002 for Beirut and Mount Lebanon respectively), educating the public about immunization (ORa = 3.012, [95%CI 1.281:7.083], P = 0.011); and vaccine administration. Conclusion: The study highlights the need for additional immunization training programs to pharmacists to expand their ability and role as immunizers. It also provides intuition for policy makers to upgrade legislation relating to pharmacy continuing education and immunization training in order to enable pharmacists to have a greater role in direct vaccination.

Knowledge and attitudes toward cigarette and narghile smoking among previous smokers in Lebanon.

To evaluate the proportions of current cigarette smokers (CCS) and current narghile smokers (CNS) as well as previous cigarette smokers (PCS) and previous narghile smokers (PNS) and to assess smoking knowledge and attitudes toward supporting smoking ban or cessation among previous compared with current smokers. This cross-sectional study took place between May and December 2018, and enrolled a sample of 1598 exclusive cigarette smokers (ECS) and 2091 exclusive narghile smokers (ENS), representative of all Lebanese governorates. A questionnaire designed specifically for this study was used to collect data. Among ECS, 45.2% were CCS and 54.8% were PCS. Among ENS, 83.5% were CNS and 16.5% were PNS. Higher age (adjusted odds ratio (aOR) (95% confidence interval (CI)) = 1.02 (1.01; 1.03)), higher knowledge (1.05 (1.02; 1.08)), and attitude scores (1.11(1.09; 1.13)) were significantly associated with higher odds of being PCS. Higher age (1.02 (1.01; 1.03)), being employed (1.32 (1.004; 1.72)), higher knowledge (1.04 (1.02; 1.07)), and attitude scores (1.09 (1.07; 1.12)) were significantly associated with higher odds of being PNS. Previous smokers have higher knowledge and better attitude toward supporting smoking cessation compared with current smokers. A better knowledge along with effective interventions, might lead to a positive attitude toward supporting smoking ban or smoking cessation among the general population.

Comparing cigarette smoking knowledge and attitudes among smokers and non-smokers.

Smoking prevalence in Lebanon was reported by the World Health Organization to be 43%, which is among the highest rates in the Arab nation. The objectives of this study were to assess cigarette smoking knowledge and attitude among smokers and non-smokers using validated scales in the Lebanese general population and evaluate their association with current cigarette smoking; a secondary objective is to assess the dose effect relationship of knowledge and attitude with cumulative smoking. This cross-sectional took place between May and December 2018, and enrolled a sample of 2623 participants, representative from all Lebanese governorates. A questionnaire about knowledge of the harmful effects of tobacco and attitude toward smoking bans retrieved from other studies was used to collect data. Male gender (ORa = 0.75), having a low monthly income (ORa = 1.56) and a higher passive smoking score (ORa = 1.25), were significantly associated with higher odds of being current smokers. Higher knowledge score (ORa = 0.97) and positive attitude toward smoking ban score (ORa = 0.94) were significantly associated with lower odds of being current smokers. In addition, increased age (ß = 15.21) and higher passive smoking score (ß = 26.58) were significantly associated with higher cumulative cigarette smoking. More positive attitude toward smoking ban score (ß = - 6.51) and having a university degree (ß = - 68.35) were significantly associated with lower cumulative cigarette smoking. Higher knowledge about the smoking-related health problems and better attitudes toward smoking ban were observed among non-smokers compared to smokers. It is important to increase awareness campaigns and to propose effective interventions to put in place an adequate culture of smoking cessation among the general population.

Serum cytokine profiles as predictors of asthma control in adults from the EGEA study.

BACKGROUND: To which extent serum cytokines may predict asthma control in adults remains understudied. OBJECTIVES: We investigated cross-sectional and longitudinal associations between cytokine profiles and asthma outcomes. METHODS: Serum interleukin (IL)-1Ra, IL-5, IL-7, IL-8, IL-10, IL-13 and TNF-α levels were determined in 283 adults with current asthma from the 2nd survey of the Epidemiological Study on the Genetics and Environment of Asthma (EGEA2). Participants were followed-up seven years later. Asthma symptom control was assessed according to GINA 2015 guidelines. Cytokine profiles were identified by principal component (PC) analyses, and expressed as above/below the median. RESULTS: The first two PCs captured 82.5% of the variability. While all seven cytokines scored high on PC1, only IL-1Ra and IL-10 scored high on PC2. At EGEA2, neither PC1 nor PC2 were related to exacerbations, asthma attacks, asthma symptom control, lung function, or allergic diseases. High level of PC1 (above the median) was associated with higher blood neutrophil counts (P = 0.02), while high level of PC2 was associated with lower IgE levels (P = 0.04). High level of PC2 at EGEA2 was associated with lower bronchial hyperresponsiveness (adjusted(a) OR[95%CI] = 0.46[0.23; 0.91]) and with subsequent lower risk of worsening asthma control and attacks (aOR[95%CI] = 0.24[0.09; 0.60]; 0.31[0.11; 0.85] respectively). CONCLUSIONS: Serum cytokine profiles with high levels of IL-1Ra and IL-10 were associated with lower subsequent risks of worsening asthma control and attacks in adults. This study adds new findings for the role of serum cytokine profiles to help identifying adults with subsequent risk of asthma burden that could be targeted for specific therapies.

Surfactant protein D, a clinical biomarker for chronic obstructive pulmonary disease with excellent discriminant values.

Biological markers can help to better identify a disease or refine its diagnosis. In the present study, the association between surfactant protein D (SP-D) and chronic obstructive pulmonary disease (COPD) was studied among subjects consulting for respiratory diseases or symptoms and was compared with C-reactive protein (CRP) and fibrinogen. A further aim of this study was to identify the optimal cut-off point of SP-D able to discriminate COPD patients. A case-control study including 90 COPD patients, 124 asthma patients and 180 controls was conducted. Standardized questionnaires were administered and lung function tests were performed. Biological markers were measured in blood samples according to standardized procedures. The association between SP-D and COPD was investigated using logistic regression models. Receiver-operating characteristic curves were used for threshold identification. SP-D levels above the median value were positively associated with COPD [adjusted odds ratio (OR)=3.86, 95% confidence interval (CI): 1.51-9.85, P=0.005). No associations with COPD or asthma were found for CRP or fibrinogen levels. Scores for COPD diagnosis in all COPD patients or ever-smoker COPD patients were identified (sensitivity, 76.4 and 77.8%; specificity, 89.3 and 88.5%, respectively). The results indicate that SP-D can differentiate COPD from other respiratory symptoms or diseases. Used with socio-demographic characteristics and respiratory symptoms, SP-D is able to discriminate COPD patients from controls, particularly among smokers.