Respiratory Medicine (2011) 105, 1611e1621
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Rhinitis phenotypes correlate with different symptom presentation and risk factor patterns of asthma ¨tvall a, Go ¨ran Wennergren a,c, Jonas Eriksson a,*, Anders Bjerg a,b, Jan Lo ¨nmark a,b,d, Kjell Tore ´n a,e, Bo Lundba ¨ck a,b Eva Ro a
Krefting Research Centre, Department of Internal Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden b The OLIN Studies, Department of Medicine, Sunderby Central Hospital of Norrbotten, Lulea˚, Sweden c Department of Paediatrics, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden d Environmental & Occupational Medicine, Department of Medicine, University of Umea˚, Umea˚, Sweden e Environmental & Occupational Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden Received 26 November 2010; accepted 9 June 2011 Available online 18 July 2011
KEYWORDS Asthma; Rhinitis; Chronic rhinosinusitis epidemiology; Population survey
Summary Background: Asthma and rhinitis frequently coexist, but no population study has previously determined the relationship between nasal comorbidities and symptom expression and risk factors of asthma. Methods: In 2008, a postal questionnaire on respiratory health was sent to 30 000 randomly selected subjects aged 16e75 years in West Sweden; 29218 could be traced and 18 087 (62%) responded. The questionnaire included questions on asthma, rhinitis, chronic rhinosinusitis, respiratory symptoms and possible determinants. Results: Prevalence of allergic rhinitis in asthma was 63.9% and of asthma in allergic rhinitis 19.8%. Prevalence of chronic rhinosinusitis in asthma was 8.4% and of asthma in chronic rhinosinusitis 24.4%. Asthma subjects with chronic rhinitis, or chronic rhinosinusitis, had more symptoms of asthma and bronchitis than those without rhinitis (p < 0.001). There was an obvious trend of higher ORs for various environmental exposures including occupational exposure to dust, gases and fumes (OR 2.32 vs. OR 1.44), visible mould at home (OR 1.72 vs. OR 1.27) and water damage at home (OR 1.82 vs. OR 1.06) for asthma with chronic rhinosinusitis than for asthma with allergic rhinitis. Family history of allergy yielded a higher OR for asthma with allergic rhinitis than with asthma with chronic rhinosinusitis (OR 7.15 vs. OR 4.48).
* Corresponding author. Krefting Research Centre, Sahlgrenska Academy, University of Gothenburg, Box 424, SE - 405 30 Gothenburg, Sweden. Tel.: þ46 703 274729; fax: þ46 31 786 6730. E-mail address:
[email protected] (J. Eriksson). 0954-6111/$ - see front matter ª 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.rmed.2011.06.004
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J. Eriksson et al. Conclusion: Considerable overlap between asthma and nasal comorbidities was documented, confirming a close relationship between nasal disease and asthma. Allergic rhinitis, chronic rhinitis and chronic rhinosinusitis were associated with different risk factor patterns and symptom expression of asthma. Thus, different nasal comorbidities may reflect different phenotypes of asthma. ª 2011 Elsevier Ltd. All rights reserved.
Introduction Asthma and rhinitis are common chronic disorders with an estimated 700 million sufferers worldwide.1 Both asthma and rhinitis are considered syndromes with a number of clinical phenotypes,2,3 as well as biological endotypes.4 The conditions frequently coexist, both in atopic and nonatopic individuals.5 Rhinitis is further considered an important risk factor for developing asthma.6,7 Concomitant rhinitis appears to impair asthma control,8 whereas adequate treatment of allergic rhinitis seems to be beneficial also for asthma.9e11 While a number of population-based studies have investigated the association between asthma and allergic rhinitis,12e15 studies on the correlation between asthma and chronic nasal symptoms are few.15e17 Studies from otolaryngology and asthma clinics have suggested considerable comorbidity between asthma and chronic rhinosinusitis.17 However, mainly due to previous lack of consensus in the definition of chronic rhinosinusitis, population-based studies are few. There are at present no published population-based studies on comorbidity of asthma and chronic rhinosinusitis. The genetic component of asthma and rhinitis is considered to be of great importance.18 Even so, a number of environmental risk factors, including occupational exposure to irritant factors and home dampness, have been associated with the conditions.18e21 Although various studies have presented risk factors for asthma and rhinitis separately,7,12,19e23 to the authors’ knowledge, no previous study has presented risk factors for asthma with different nasal comorbidities. The aim of this study was to investigate the prevalence of asthma and lower respiratory symptoms in subjects with allergic rhinitis, chronic rhinitis and chronic rhinosinusitis and vice versa (i), how the expression of lower respiratory symptoms in asthma subjects varies with different nasal comorbidities (ii) and what the risk factors are for asthma with different nasal comorbidities (iii).
Methods Study population In 2008, a self-administered questionnaire was mailed with three reminders to 30 000 inhabitants in West Sweden, aged 16e75 years. By computerised randomisation 15 000 subjects were selected from the urbanised area of Gothenburg. Similarly, a random sample of 15 000 subjects of the same age was selected from the rest of the region. Names and addresses were provided by the Swedish
Population Register. The invited individuals were given the possibility to respond either by mail or over the internet. Of the 29 218 subjects that were traceable, 18 087 (62%) participated.22,23 A study of none- and late-response has confirmed the representativeness of the study sample for the population in the studied areas.24
Questionnaire The study questionnaire consisted of the Swedish OLIN study questionnaire,25 with additional questions about smoking and occupational and environmental exposures, and the Swedish version of the GA2LEN questionnaire.2 The OLIN questionnaire has been used in several large scale studies in northern Europe and other parts of the world and contains questions about obstructive respiratory diseases, rhinitis, respiratory and nasal symptoms and possible determinants of disease, such as smoking habits and family history of asthma and allergy.12,22e30
Definitions Asthma As the diagnosis of asthma is arbitrary, three different definitions of asthma were used: report of having ever had asthma (ever asthma), physician-diagnosed asthma and current asthma. Current asthma was defined as ever asthma or physician-diagnosed asthma and at least one out of: current use of asthma medication, attacks of shortness of breath, any wheeze, and recurrent wheeze. Rhinitis Allergic rhinitis was defined as having ever had allergic eye or nose problems including hay fever, while chronic rhinitis was defined as having either runny nose or nasal congestion more or less constantly. Chronic rhinosinusitis was defined as at least three of the following symptoms: nasal blockage, mucus discharge, facial pain or pressure and reduction of smell, for more than 12 weeks during the past 12 months. Lower respiratory symptoms Waking with tight chest was defined as having woken up with a sensation of chest tightness. Dyspnoea grade 3 was defined as necessity to walk slower than contemporaries on level ground because of breathlessness, following the definition from the Medical Research Council Dyspnoea Index. All other lower respiratory symptoms have been defined elsewhere.22 Family history Family history of asthma was defined as a positive answer to the question: ‘Has any of your parents or siblings ever had
Asthma and nasal comorbidities asthma’, and family history of allergic rhinitis was defined as a positive answer to the question: ‘Has any of your parents or siblings ever had eye or nose problems (hay fever)’. Exposures Current smokers reported smoking during the year preceding the survey, and were classed as light-moderate smokers if they smoke less than 15 cigarettes per day and heavy smokers if they smoke 15 cigarettes per day or more; Ex-smokers reported having stopped smoking at least 12 months preceding the survey; Non-smokers reported neither smoking nor ex-smoking. Occupational exposure was defined as having been substantially exposed to dust, gases or fumes at work. Visible mould at home and water damage at home were defined as suffering from any such incidence during the past 10 years. Farm childhood was defined as having lived on a farm during your first five years of life. Classes of level of education were: completion of primary school, secondary school or higher education (under-graduate, graduate and post-graduate). Degrees of urbanisation were categorised based on the number of inhabitants in the localities of residence. Metropolitan Gothenburg, with approximately 700 000 inhabitants, was used as a separate entity, while other localities with more than 10 000 inhabitants were considered mid-size towns (all with less than 100 000 inhabitants). Localities with 500 to 10 000 inhabitants were considered small towns and those with less than 500 inhabitants rural areas. The classification was performed by matching the subjects’ address information with official population data from Statistics Sweden.31
1613 rhinosinusitis, respectively, as is presented in Venndiagrams (Fig. 1a and b). Of subjects with physiciandiagnosed asthma, 63.9% had allergic rhinitis, 39.8% had chronic rhinitis and 8.4% had chronic rhinosinusitis. Of subjects with chronic rhinosinusitis, 82.7% had chronic rhinitis and 54.0% had allergic rhinitis. Prevalence of ever asthma, physician-diagnosed asthma, current asthma and current use of asthma medication was considerably (p < 0.001) higher in subjects with allergic rhinitis, chronic rhinitis and chronic rhinosinusitis, respectively, than in subjects without rhinitis or rhinosinusitis (Table 1). Prevalence of current asthma was studied in relation to combinations of allergic rhinitis, nasal congestion and runny nose (Fig. 2). The prevalence of current asthma increased with the number of nasal conditions, 2.8% in no nasal condition vs. 28.5% in three nasal conditions.
Rhinitis in asthma The prevalence of allergic rhinitis, chronic rhinitis and chronic rhinosinusitis, respectively, increased with increasing occurrence of symptoms common in asthma
Analyses Statistical analyses were performed using SPSS version 17.0 (Chicago, IL, USA). Comparisons of proportions were tested with two-sided Fisher’s exact test. Linear-by-linear association chi square test was used for testing for trends. A pvalue of
