Accordini et al. BMC Pulmonary Medicine (2015) 15:10 DOI 10.1186/s12890-015-0008-0 RESEARCH ARTICLE Open Access The impact of asthma, chronic bronchitis and allergic rhinitis on all-cause hospitalizations and limitations in daily activities: a population-based observational study Simone Accordini1*, Angelo Guido Corsico2, Lucia Calciano1, Roberto Bono3, Isa Cerveri2, Alessandro Fois4, Pietro Pirina4, Roberta Tassinari3, Giuseppe Verlato1 and Roberto de Marco1 Abstract Background: Chronic respiratory diseases are a significant cause of morbidity and mortality worldwide. We sought to evaluate the impact of asthma, chronic bronchitis and allergic rhinitis on all-cause hospitalizations and limitations in daily activities in adults. Methods: In the Gene Environment Interactions in Respiratory Diseases study (2007/2010), a screening questionnaire was mailed to 9,739 subjects aged 20–44 (response rate: 53.0%) and to 3,480 subjects aged 45–64 (response rate: 62.3%), who were randomly selected from the general population in Italy. The questionnaire was used to: identify the responders who had asthma, chronic bronchitis, allergic rhinitis or asthma-like symptoms/dyspnoea/ other nasal problems; evaluate the total burden [use of hospital services (at least one ED visit and/or one hospital admission) and number of days with reduced activities (lost working days and days with limited, not work related activities) due to any health problems (apart from accidents and injuries) in the past three months]; evaluate the contribution of breathing problems to the total burden (hospitalizations and number of days with reduced activities specifically due to breathing problems). Results: At any age, the all-cause hospitalization risk was about 6% among the subjects without any respiratory conditions, it increased to about 9-12% among the individuals with allergic rhinitis or with asthma-like symptoms/ dyspnoea/other nasal problems, and it peaked at about 15-18% among the asthmatics with chronic bronchitis aged 20–44 and 45–64, respectively. The expected number of days with reduced activities due to any health problems increased from 1.5 among the subjects with no respiratory conditions in both the age classes, to 6.3 and 4.6 among the asthmatics with chronic bronchitis aged 20–44 and 45–64, respectively. The contribution of breathing problems to the total burden was the highest among the asthmatics with chronic bronchitis (23-29% of the hospitalization risk and 39-50% of the days with reduced activities, according to age). Conclusions: The impact of asthma, chronic bronchitis and allergic rhinitis on all-cause hospitalizations and limitations in daily activities is substantial, and it is markedly different among adults from the general population in Italy. The contribution of breathing problems to the total burden also varies according to the respiratory condition. Keywords: Burden of allergic rhinitis, Burden of asthma, Burden of chronic bronchitis, Determinants * Correspondence: [email protected] 1Unit of Epidemiology and Medical Statistics, Department of Public Health and Community Medicine, University of Verona, Verona, Italy Full list of author information is available at the end of the article © 2015 Accordini et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Accordini et al. BMC Pulmonary Medicine (2015) 15:10 Page 2 of 9 Background Table 1 Distribution of the design variables Asthma, chronic bronchitis and allergic rhinitis are com- 20-44 yrs 45-64 yrs p-value mon health problems in industrialized countries [1-3] N° of eligible subjects* 9739 3480 - and they often coexist [4-6]. Furthermore, chronic bron- N° of responders 5162 (53.0) 2167 (62.3) <0.001 chitis is associated with both a more severe form of the (response rate, %) disease and poor control of symptoms in subjects with Season at the time asthma [7,8], and it may indicate the presence of the of response, % Spring 46.2 51.5 <0.001 asthma-chronic obstructive pulmonary disease (COPD) Summer 15.2 8.6 overlap syndrome [9,10]. Autumn 32.0 30.9 Asthma generates a high socio-economic burden Winter 6.6 9.0 among European adults, which significantly increases when chronic bronchitis is also present [11,12]. More- Telephone interview, % 11.6 9.6 0.012 over, asthma and allergic rhinitis together account for Females, % 53.6 52.1 0.267 most of the allergy-related morbidity associated with the *Eligible = initial sample – (dead or moved away from the target area). respiratory system [13]. Therefore, real-world evalua- tions of the impact of these diseases in the general popu- lation are fundamental to meet the widespread need for updated estimates, which should be used as a valid sup- Ethics statement port to public health decisions. Ethics approval was obtained in each centre from the ap- In recent years, the socio-economic impact of asthma, propriate ethics committee (“Comitato di Bioetica della chronic bronchitis and allergic rhinitis has been largely Fondazione IRCCS Policlinico San Matteo di Pavia”; investigated [11,12,14-16]. However, in many studies, the “Comitato di Bioetica dell’Azienda Sanitaria Locale di total burden (i.e. the burden due to any health problems) Sassari”; “Comitato Etico dell’Azienda Sanitaria Locale in patients with these respiratory illnesses has not been TO/2 di Torino”; “Comitato Etico per la Sperimentazione estimated because only disease-related costs have been dell'Azienda Ospedaliera Istituti Ospitalieri di Verona”). considered. Moreover, the total burden should be com- All participants were fully informed about all aspects of pared between patients with a certain disease and un- the research project and consented to complete and re- affected subjects from the general population. Indeed, a turn the questionnaire. better understanding of the burden of these respiratory diseases requires the assessment of their total impact on Screening questionnaire and definitions the health and social systems. The screening questionnaire (available at www.geird.org) is The aim of the present paper is to compare all-cause hos- a modified version of the questionnaire used in the Italian pitalizations and limitations in daily activities among adult Study on Asthma in Young Adults [18]. It contains vali- subjects with asthma, chronic bronchitis or allergic rhinitis, dated questions (mainly taken from the European Commu- and unaffected individuals from the general population, nity Respiratory Health Survey questionnaires [19]) on and to assess the contribution of breathing problems to the asthma (self-report of the disease during lifetime with or total burden. To fulfil these purposes, the data from the without a physician’s diagnosis, frequency of asthma screening stage of the Gene Environment Interactions in attacks, and use of anti-asthmatic drugs in the past Respiratory Diseases (GEIRD) study [17] were used. 12 months), asthma-like symptoms (wheezing, nocturnal tightness in the chest, and attacks of shortness of breath at Methods night time in the past 12 months), chronic cough and Design of the study phlegm, and nasal problems, as well as questions on occu- The screening stage of GEIRD was a cross-sectional sur- pational status, smoking habits and outdoor air pollution vey on respiratory health, which was carried out between (frequency of heavy traffic near home and living near in- 2007 and 2010 in Italy [17]. A total sample of 9,739 sub- dustrial plants). jects aged 20–44 and of 3,480 subjects aged 45–64 On the basis of their answers to the questions de- (men/women ratio = 1) was randomly selected from the scribed above, the responders to the screening question- general population in four centres (Pavia, Sassari, Turin naire were classified as subjects with: and Verona) by using the local health authority registers. A screening questionnaire was mailed to each individual asthma (i.e. self-report of the disease during lifetime up to three times and then administered by telephone in with or without a physician’s diagnosis or at least case of nonresponse. Overall, the responders were 5,162 one asthma attack in the past 12 months or use of (53.0%) in the 20–44 age group and 2,167 (62.3%) in the anti-asthmatic drugs in the past 12 months) and 45–64 age group (Table 1). chronic bronchitis (i.e. cough and phlegm on most Accordini et al. BMC Pulmonary Medicine (2015) 15:10 Page 3 of 9 days for a minimum of three months a year and for The prevalence of each respiratory condition was esti- at least two successive years); mated by using a logistic model, which included age class, chronic bronchitis without asthma; centre and the potential confounders reported above, as asthma without chronic bronchitis; covariates. The all-cause hospitalization risk [i.e. the pro- allergic rhinitis (i.e. any nasal allergies, including hay portion of subjects with at least one ED visit and/or one fever) without asthma and chronic bronchitis; hospital admission due to any health problems (apart from asthma-like symptoms or dyspnoea or other nasal accidents and injuries) in the past three months] and the problems without asthma, chronic bronchitis and expected number of days with reduced activities due to allergic rhinitis; any health problems in the same period were estimated by no respiratory conditions (i.e. none of the conditions using logistic and negative binomial models [21], respect- described above). ively, which included the respiratory condition crossed by the age class, centre and the potential confounders re- In addition, the responders were considered exposed to ported above, as covariates. Since the subjects were nested a high level of outdoor air pollution if they had reported into centres, clustered sandwich estimators of the variance a continuous passage of trucks near home and/or living were used.