Sara Maio

Epidemiology of chronic obstructive pulmonary disease: Health effects of air pollution

Abstract:  COPD is one of the leading causes of morbidity and mortality in the industrialized and the developing countries. According to the prediction of the World Health Organization, COPD will become the third leading cause of mortality and the fifth cause of disability in 2020 worldwide. In epidemiology, distinct phenotypic entities converge on the term COPD, so that prevalence and mortality data may be inclusive of chronic bronchitis, emphysema and asthma; moreover, the assessment of prevalence rates may change considerably according to the diagnostic tools used. Thus, a considerable problem is to estimate the real prevalence of COPD in the general population. COPD is determined by the action of a number of various risk factors, among which, the most important is cigarette smoking. However, during the last few decades, evidence from epidemiological studies finding consistent associations between air pollution and various outcomes (respiratory symptoms, reduced lung function, chronic bronchitis and mortality), has suggested that outdoor air pollution is a contributing cause of morbidity and mortality. In conclusion, epidemiological studies suggest that air pollution plays a remarkable role in the exacerbation and in the pathogenesis of chronic respiratory diseases. Thus, respiratory physicians, as well as public health professionals, should advocate for a cleaner environment.

Adverse effects of outdoor pollution in the elderly.

With fewer newborns and people living longer, older people are making up an increasing fraction of the total population. Epidemiological evidence shows that older-age-related health problems affect a wide and expanding proportion of the world population. One of the major epidemiological trends of this century is the rise of chronic diseases that affect more elderly than younger people. A total of 3.7 million premature deaths worldwide in 2012 are attributable to outdoor air pollution; the susceptibility to adverse effects of air pollution is expected to differ widely between people and within the same person, and also over time. Frailty history, a measure of multi-system decline, modifies cumulative associations between air pollution and lung function. Moreover, pre-existing diseases may determine susceptibility. In the elderly, due to comorbidity, exposure to air pollutants may even be fatal. Rapid and not-well-planned urbanization is associated with high level of ambient air pollution, mainly caused by vehicular exhausts. In general, there is sufficient evidence of the adverse effects related to short-term exposure, while fewer studies have addressed the longer-term health effects. Increased pollution exposures have been associated with increased mortality, hospital admissions/emergency-room visits, mainly due to exacerbations of chronic diseases or to respiratory tract infections (e.g., pneumonia). These effects may also be modulated by ambient temperature and many studies show that the elderly are mostly vulnerable to heat waves. The association between heat and mortality in the elderly is well-documented, while less is known regarding the associations with hospital admissions. Chronic exposure to elevated levels of air pollution has been related to the incidence of chronic obstructive pulmonary disease (COPD), chronic bronchitis (CB), asthma, and emphysema. There is also growing evidence suggesting adverse effects on lung function related to long-term exposure to ambient air pollution. Few studies have assessed long-term mortality in the elderly. It is still unclear what are the pollutants most damaging to the health of the elderly. It seems that elderly subjects are more vulnerable to particulate matter (PM) than to other pollutants, with particular effect on daily cardio-respiratory mortality and acute hospital admissions. Not many studies have targeted elderly people specifically, as well as specific respiratory morbidity. Most data have shown higher risks in the elderly compared to the rest of the population. Future epidemiological cohort studies need to keep investigating the health effects of air pollutants (mainly cardiopulmonary diseases) on the elderly.

Geographical information system and environmental epidemiology: a cross-sectional spatial analysis of the effects of traffic-related air pollution on population respiratory health

BackgroundTraffic-related air pollution is a potential risk factor for human respiratory health. A Geographical Information System (GIS) approach was used to examine whether distance from a main road (the Tosco-Romagnola road) affected respiratory health status.MethodsWe used data collected during an epidemiological survey performed in the Pisa-Cascina area (central Italy) in the period 1991-93. A total of 2841 subjects participated in the survey and filled out a standardized questionnaire on health status, socio-demographic information, and personal habits. A variable proportion of subjects performed lung function and allergy tests. Highly exposed subjects were defined as those living within 100 m of the main road, moderately exposed as those living between 100 and 250 m from the road, and unexposed as those living between 250 and 800 m from the road. Statistical analyses were conducted to compare the risks for respiratory symptoms and diseases between exposed and unexposed. All analyses were stratified by gender.ResultsThe study comprised 2062 subjects: mean age was 45.9 years for men and 48.9 years for women. Compared to subjects living between 250 m and 800 m from the main road, subjects living within 100 m of the main road had increased adjusted risks for persistent wheeze (OR = 1.76, 95% CI = 1.08-2.87), COPD diagnosis (OR = 1.80, 95% CI = 1.03-3.08), and reduced FEV1/FVC ratio (OR = 2.07, 95% CI = 1.11-3.87) among males, and for dyspnea (OR = 1.61, 95% CI = 1.13-2.27), positivity to skin prick test (OR = 1.83, 95% CI = 1.11-3.00), asthma diagnosis (OR = 1.68, 95% CI = 0.97-2.88) and attacks of shortness of breath with wheeze (OR = 1.67, 95% CI = 0.98-2.84) among females.ConclusionThis study points out the potential effects of traffic-related air pollution on respiratory health status, including lung function impairment. It also highlights the added value of GIS in environmental health research.

Indoor air pollution and respiratory health in the elderly

Data on respiratory effects of indoor air pollution in elderly are scanty. The purpose of this review is to summarize current knowledge on adverse respiratory effects of indoor air pollution in individuals aged over 65 years, by presenting existing epidemiological evidence. Using MEDLINE database through PubMed, we identified relevant publications published between 1991 and 2011 in English on respiratory health effects of indoor air pollution in elderly (>65 years). A total of 61 studies were found and after application of the inclusion criteria: (i) epidemiologic studies published in English in peer-reviewed journals between January 1991 and December 2011, (ii) study population with age over or equal 65 years, and (iii) outcome of respiratory symptoms and disease with the exclusion of lung cancer, 33 relevant publications were selected. Most of them showed significant relationships between exposure to major indoor air pollutants and various short-term and long-term respiratory health outcomes such as wheezing, breathlessness, cough, phlegm, asthma, COPD, lung cancer and more rarely lung function decline. The most consistent relationship is found between chronic obstructive pulmonary disease (COPD) and environmental tobacco smoke (ETS). Further studies in the elderly population are needed in order to define causal relationships between exposures to indoor air pollution and underlying mechanisms in this sub-population.

The European Respiratory Society spirometry tent: a unique form of screening for airway obstruction.

In order to raise public awareness of the importance of early detection of airway obstruction and to enable many people who had not been tested previously to have their lung function measured, the European Lung Foundation and the European Respiratory Society (ERS) organised a spirometry testing tent during the annual ERS Congresses in 2004–2009. Spirometry was performed during the ERS Congresses in volunteers; all participants answered a simple, brief questionnaire on their descriptive characteristics, smoking and asthma. Portable spirometers were freely provided by the manufacturer. Nurses and doctors from pulmonary departments of local hospitals/universities gave their service for free. Lower limit of normal (LLN) and Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria for diagnosing and grading airway obstruction were used. Of 12,448 participants in six congress cities, 10,395 (83.5%) performed acceptable spirometry (mean age 51.0±18.4 yrs; 25.5% smokers; 5.5% asthmatic). Airway obstruction was present in 12.4% of investigated subjects according to LLN criteria and 20.3% according to GOLD criteria. Through multinomial logistic regression analysis, age, smoking habits and asthma were significant risk factors for airway obstruction. Relative risk ratio and 95% confidence interval for LLN stage I, for example, was 2.9 (2.0–4.1) for the youngest age (≤19 yrs), 1.9 (1.2–3.0) for the oldest age (≥80 yrs), 2.4 (2.0–2.9) for current smokers and 2.8 (2.2–3.6) for reported asthma diagnosis. In addition to being a useful advocacy tool, the spirometry tent represents an unusual occasion for early detection of airway obstruction in large numbers of city residents with an important public health perspective.

COPD management according to old and new GOLD guidelines: an observational study with Italian general practitioners

Abstract Background: Guideline recommendations for COPD management are only partially applied within primary care clinical practice. Objective: To compare the COPD management by Italian general practitioners (GPs) according to either the old GOLD (oGOLD) or the new GOLD (nGOLD) guidelines. Research design and methods: Observational study in different Italian areas. A total of 176 GPs enrolled their patients with a COPD diagnosis. Questionnaires were used to collect data on: COPD symptoms, disease severity, exacerbations, prescribed pharmacological and non-pharmacological treatments. COPD severity was estimated according to oGOLD and nGOLD guidelines. Results: A total of 526 subjects had complete information to assess COPD severity level according to guidelines (symptoms level, spirometry, history of exacerbations). The investigated subjects were more frequently males (71.2%) with a mean age of 72.5 years, and ex-smokers (44.4%). GPs reported sufficient control of the disease in 47.2% of the subjects with over two exacerbations in the last 12 months. Most patients have moderate COPD (51.5%), according to oGOLD, and belong to D groups (high risk, more symptoms) (45.6%), according to nGOLD. Overall, a low use of post-bronchodilator spirometry (65.1%) and of pulmonary rehabilitation (13.4%) was shown. The results highlighted a low prescriptive appropriateness but with higher value according to nGOLD than oGOLD: 61.4% vs 35.6%. Study limitations: Prescription data only provide limited information to judge prescribing quality, thus the results have to be evaluated with caution; moreover, this study was not designed to assess the difference between oGOLD and nGOLD. Conclusions: Guideline recommendations are applied only partially within clinical practice. A higher prescriptive appropriateness is shown by GPs using nGOLD classification. This might be due to the fact that nGOLD, with respect to oGOLD, takes into account anamnestic usual features considered by GPs in their clinical practice.

Impact of Asthma and Comorbid Allergic Rhinitis on Quality of Life and Control in Patients of Italian General Practitioners

Objective. Asthma is a disease with elevated prevalence within the general population. Although general practitioners (GPs) are among the first health-care professionals to whom patients refer for their symptoms, there are few evaluations of this disease based on data provided by the GPs. The aim of this observational study is to assess the impact of asthma and comorbid allergic rhinitis on individual/social burden, quality of life, and disease control in asthmatic patients of Italian GPs. Methods. Throughout Italy, 107 GPs enrolled 995 patients diagnosed with asthma and using anti-asthmatic drug prescriptions, or with asthma-like symptoms during the previous 12 months. Data were collected through questionnaires filled out by GPs and patients. Results. Of the 995 asthmatic patients, 60.6% had concomitant allergic rhinitis (R+A), 39.4% had asthma alone. The latter, compared to those with R+A, showed significantly lower prevalence of intermittent asthma (37.5% vs. 55.6%) and higher prevalence of mild, moderate, and severe persistent asthma (28.4% vs. 23.2%, 28.7% vs. 18.8%, and 5.4% vs 2.4%, respectively). Individual/social burden due to asthma was frequent and increased with disease severity: 87.5% of severe persistent asthma patients reported at least one medical consultation in the last 12 months, 37.5% emergency department visits, 26.7% hospitalization, and 62.5% limitations in daily activities. Control and quality of life were inversely associated with disease severity and were worse in patients with R+A than in those with asthma alone. Conclusions. This study showed the negative impact of high severity levels and comorbid allergic rhinitis on quality of life of asthmatic patients and on individual/social burden due to asthma in an Italian GPs setting.

Respiratory symptoms/diseases prevalence is still increasing: a 25-yr population study

BACKGROUND Few epidemiological surveys on general population samples estimated changes in prevalence of respiratory symptoms/diseases over a long time interval; our study aims to quantify the temporal changes in the prevalence rates of asthma, allergic rhinitis and Chronic Obstructive Pulmonary Disease (COPD) after 25 years from baseline. METHODS A general population sample participated in 3 cross-sectional surveys carried out in Central Italy (Pisa) in 1985-88 (n = 3865), 1991-93 (n = 2841), 2009-11 (n = 1620). 2276 (47%) subjects participated in at least 1 survey, 1723 (35.5%) in at least 2 surveys and 849 (17.5%) in all the 3 surveys. All subjects filled in a standardized questionnaire about health status and risk factors; a sub-sample performed spirometry. Chi-square test was used to compare adjusted prevalence rates of respiratory symptoms/diseases and descriptive characteristics among the surveys. Generalised estimating equations (GEE) were used to analyze the association between respiratory symptoms/diseases and risk factors. RESULTS There was an increasing trend in prevalence rates of all respiratory symptoms/diseases throughout the surveys: current asthma attacks (1st-3rd survey prevalence: 3.4-7.2%), allergic rhinitis (16.2-37.4%), usual phlegm (8.7-19.5%) and COPD (2.1-6.8%) more than doubled. The GEE model confirmed these increasing trends, indicating higher risk of having respiratory symptoms/diseases in the second and third surveys. CONCLUSIONS While asthma and allergic rhinitis increasing trends were confirmed, with respect to other international studies, also a COPD increasing prevalence rates was shown.

The ARGA study with Italian general practitioners: prescriptions for allergic rhinitis and adherence to ARIA guidelines

Abstract Background: General practitioners (GPs) are the healthcare professionals to whom patients with rhinitis firstly refer for their symptoms. Objective: In the present study, we assessed drug prescriptions for allergic rhinitis (AR) and evaluated prescriptive adherence to ARIA treatment guidelines. Methods: Data on 1379 AR patients were collected by 107 Italian GPs. Adherence to ARIA guidelines was evaluated according to AR severity classification. Results: AR was diagnosed by GPs as mild intermittent for 46.2% of patients, mild persistent for 26.6%, moderate–severe intermittent for 20.2%, and moderate–severe persistent for 7%; 43.7% of AR patients had concomitant asthma. The most frequently prescribed therapeutic groups were antihistamines (anti-H, 76%) and nasal corticosteroids (NCS, 46%). Anti-H were significantly used more often to treat AR alone than AR + asthma (85 vs. 68%, p < 0.001), whereas NCS were used more often to treat AR + asthma than AR alone (50 vs. 42%, p = 0.01). Among patients with only mild intermittent AR, 39% were prescribed combined therapy. Among patients with moderate–severe persistent AR, 30% of those with AR alone and 18% of those with AR + asthma were prescribed monotherapy based on anti-H. GPs were more compliant with ARIA guidelines while treating AR alone (57%) than AR + asthma (46%) patients. The adherence increased according to the severity grade and was satisfactory for moderate–severe persistent AR (89% for AR alone and 95% for AR + asthma). Conclusions: Adherence to ARIA guidelines is satisfactory only for treatment of more severe patients, thus GPs often tend to treat patients independently from ARIA guidelines. Since prescription data only provide limited information to judge prescribing quality, some deviation from the gold standard are to be expected.

Percentiles of inspiratory capacity in healthy nonsmokers: a pilot study.

Background: Over the past decade inspiratory capacity (IC) has received increasing attention, especially in studies on chronic obstructive pulmonary disease. Though a few recent studies provide reference values for IC, still little is known on the distribution of its values in healthy subjects. Objective: To estimate percentiles of IC in a sample of healthy nonsmokers by applying quantile regression. Methods: We applied quantile regression to estimate seven percentiles of IC from 5 to 95% for a given age, height and body mass index, separately in males and females, in a sample of 411 healthy nonsmokers, aged 8–73 years, drawn from the general population in Northern Italy. Results: The magnitude and statistical significance of the effect of age, height and body mass on IC varied across percentiles and between genders. When the 50th percentile of IC was compared with the predicted values of several studies, including those published by the European Community for Coal and Steel, the differences were as large as 0.86 liters in males and 0.90 liters in females. The possible advantage of the 5th percentile predicted from quantile regression over the ‘traditional 5th percentile’ as lower limit of normal was also illustrated. Conclusions: Inference on percentiles, rather than just the mean, of IC and other lung function measures may help in the future to better understand the effect of various risk factors, model growth curves and derive more accurate reference values.