|Year : 2019 | Volume
| Issue : 4 | Page : 278-284
|Prevalence and factors associated with adult bronchial asthma in Aseer region, Southwestern Saudi Arabia
Badr Rashed Al Ghamdi1, Emad Abdulkadir Koshak2, Hussein Mohammad Ageely3, Fakhreldin Mohamed Omer4, Nabil Joseph Awadalla5, Ahmed A Mahfouz6
1 Department of Internal Medicine, College of Medicine, King Khalid University, Abha, Saudi Arabia
2 Department of Internal Medicine, College of Medicine, King Abdul Aziz University, Jeddah, Saudi Arabia
3 Department of Internal Medicine, College of Medicine, Jazan University, Jazan, Saudi Arabia
4 Department of Clinical Microbiology, College of Medicine, King Khalid University, Abha, Saudi Arabia
5 Department of Family and Community Medicine, College of Medicine, King Khalid University, Abha, Saudi Arabia; Department of Community Medicine, College of Medicine, Mansoura University, Mansoura, Egypt
6 Department of Family and Community Medicine, College of Medicine, King Khalid University, Abha, Saudi Arabia; Department of Epidemiology, High Institute of Public Health, Alexandria University, Alexandria, Egypt
|Date of Submission||21-Feb-2019|
|Date of Acceptance||05-Jun-2019|
|Date of Web Publication||27-Sep-2019|
Dr. Badr Rashed Al Ghamdi
Department of Internal Medicine, College of Medicine, King Khalid University, Abha
| Abstract|| |
BACKGROUND: Bronchial asthma (BA) is one of the most common chronic respiratory diseases in Saudi Arabia (SA). Most of the studies investigating the prevalence of BA in SA have focused on children and its exact prevalence in adults is unknown.
OBJECTIVES: The objective of this study is tto investigate the prevalence and factors associated with adult BA in Aseer region, southwestern SA.
METHODS: A cross-sectional study was conducted on a representative sample of adults who attended primary health care centers. A validated Arabic version of the International Study of Asthma and Allergies in Childhood questionnaire was used. The presence of wheeze in the past 12 months was used as a proxy for BA.
RESULTS: The study included 960 adults. The prevalence rate of BA was 19.2% (95% confidence interval [CI]: 16.72–21.80). In a multivariable analysis, the following factors were significantly associated with BA in adults; living in low-altitude areas (adjusted odds ratio [aOR] = 1.51, 95% CI: 1.04–2.21), being in rural areas (aOR = 1.58, 95% CI: 1.12–2.23), using analgesics (aOR = 1.52, 95% CI: 1.06–2.20), residing near heavy trucks traffics (aOR = 1.67, 95% CI: 1.13–2.46), having cats in the house (aOR = 2.27, 95% CI: 1.30–5.94), and being aged 55–64-year-old (aOR = 1.94, 95% CI: 1.02–3.69).
CONCLUSION: The prevalence of BA was high, affecting one-fifth of adults in Aseer region. The study revealed some modifiable factors significantly associated with BA in adults. There is a need to improve asthma control programs at the primary health-care level, particularly at rural and at low-altitude areas, and more focus should address the elders. In addition, enhancing community-based health promotion programs tackling the identified modifiable factors of BA are required.
Keywords: Adults, Aseer region, bronchial asthma, factors, prevalence
|How to cite this article:|
Al Ghamdi BR, Koshak EA, Ageely HM, Omer FM, Awadalla NJ, Mahfouz AA. Prevalence and factors associated with adult bronchial asthma in Aseer region, Southwestern Saudi Arabia. Ann Thorac Med 2019;14:278-84
|How to cite this URL:|
Al Ghamdi BR, Koshak EA, Ageely HM, Omer FM, Awadalla NJ, Mahfouz AA. Prevalence and factors associated with adult bronchial asthma in Aseer region, Southwestern Saudi Arabia. Ann Thorac Med [serial online] 2019 [cited 2019 Dec 16];14:278-84. Available from: http://www.thoracicmedicine.org/text.asp?2019/14/4/278/267954
Bronchial asthma (BA) is one of the most common chronic respiratory diseases affecting adults and children in Saudi Arabia (SA).,,, There are now reports that BA is a common chronic disease and local reports suggest that its prevalence is increasing. Despite these observations, several epidemiological aspects of asthma and its related clinical features, although partially addressed , are not yet settled. This have impacted the way the disease is diagnosed and managed.
In this respect, Aseer region, southwestern SA, may present a special case. This area is characterized by a special geography comprising high-altitude mountainous areas, low-altitude valleys, agricultural landscapes, as well as sea level planes. In addition, people who inhabit these areas share certain customs and traditions which may affect the epidemiology of asthma or its management.,,,
In general, the risk factors for mild or obstructive asthma in the kingdom can range from patient-related factors, for example, age, gender, obesity, smoking, exercise, stress, level of education, and the use of medicinal drugs. Other factors are environmental which include air pollution, sandstorms, weather changes, altitude, urban versus rural dwelling, and the presence of animals in and around the houses.,,,,
Most of the studies investigating the prevalence of asthma in SA have focused on children, and the exact prevalence of this disease in adults is unknown. These studies showed the prevalence of asthma in children to be in the range between 8% and 25%., Some of these studies indicated a recent and an alarming increase in the prevalence rates over the past three decades.,, This may be attributed to the rapid changes in the lifestyle related to the modernization of the Saudi society, increased exposure to environmental factors such as indoor/outdoor allergens, dust, sandstorms, and tobacco smoking and air pollution. Another explanation has attributed the increased prevalence to the hygiene hypothesis, which proposes that there is a lack of sufficient microbial exposure early in life due to pharmacological manipulations and vaccines. The present study investigated the prevalence and factors associated with adult BA in Aseer region, southwestern SA.
| Methods|| |
A cross-sectional study was conducted on a representative sample of adults in Aseer region, Southwestern SA.
Description of the study area
Aseer region extends from a high mountain chain called Sarawat down to the eastern coast of Red Sea. To the west of these mountains is a very narrow Red Sea coastal plain “Tehama.” The climate in these areas is variable depending on the altitude and proximity to the sea. Health-care facilities in the study area include 23 hospitals and 247 primary health care centers (PHCCs) (Saudi MOH portal November 2014).
Adult males and females who attended any of the selected PHCCs for any reason were the targeted groups for the study. They included apparently healthy persons attending the centers accompanying other family members for services such as antenatal care, immunization, well baby clinics, dental care, chronic disease clinics, first aids, and premarital counseling services. Definition of an adult is someone who is 20 years old or over. Using the WHO manual for sample size determination in health studies, with a conservative anticipated proportion of 10%, and absolute 2% precision at 95% of confidence interval (CI), the minimal sample size required for the study was calculated to be 865 adults.
The following were considered as exclusion criteria:
- Patients with a history of recent respiratory tract infection, individuals with a history of current or just recovering from fever, cough, and flu-like symptoms
- Individuals with ≥20 pack-years of cigarettes smoking. For Shisha smoking, the shisha smoking index (SSI) was calculated by the number of times of Shisha smoking per week multiplied by the average number of Korsis (Hagar) smoked each time. Individuals with SSI of ≥16 were also excluded 
- Patients who were already diagnosed with chronic lung disease other than asthma, for example, bronchiectasis, chronic obstructive pulmonary disorder, interstitial lung disease, and old tuberculosis infection.
Five PHCCs were randomly selected. Since the risk factors and prevalence of asthma are more likely to be affected by the environment, the selection of these PHCCs took into account their urban, rural, low- and high-altitude locations. The selected centers were Al Manhal (urban at an altitude of 2300 m above sea level), Al Mowazafin (urban at an altitude of 2300 m), Muhayel (urban at an altitude of 400 m), Tharaban (rural at an altitude of 200 m), and Al Sooda (urban at an altitude of 3200 m).
Data collection sheet
The study used a validated Arabic version of the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire that suitably modified to fit our adult survey. This questionnaire was used for all-age adults because our study aimed at studying all adult asthma in the study areas. The modified Arabic translated ISAAC questionnaire for adults was validated and used in the assessment of Asthma prevalence among adults in Sudan. A study comparing ISAACC questionnaire and the European Community Respiratory Health Survey (ECRHS) found a strong correlation between the ISAAC and ECRHS prevalence data for adults. The “presence of wheeze in the past 12 months when not having cold” as stated in the ISAAC questionnaire for asthma was used as a proxy for BA prevalence. This criterion is widely used and well accepted in epidemiological studies.
The data collection form included: written consent, demographical data, asthma Questionnaire, environment exposures as type of housing, fuel used in cooking and heating, and animals inside the house.
Scheduled visits to the selected centers were arranged by the study field teams. During such visits, adult males and females attending the selected PHCCs for any reason were invited to participate in the study. A signed informed consent is obtained from each patient before inclusion in the study. Inclusion and exclusion criteria were taken into consideration.
The compiled data were validated and analyzed using the SPSS Software program version 22 (IBM SPSS Statistics for Windows, Armonk, NY: IBM Corp). Frequency and 95% CIs were used to present asthma prevalence. Univariate and binary logistic multivariable regression were used to identify potential factors associated with asthma. Crude odds ratios and adjusted odds ratios (aOR) and their concomitant 95% CI were used to present the results. Variables included as potential risk factors in the logistic regression model were gender, age group, altitude, residence, ever smoking, using analgesics, body mass index, the presence of heavy trucks traffic outside, the use of wood for heating and cooking, and the presence of sheep, goats, camels, cats, and dogs.
| Results|| |
Description of the study sample
The present study included 960 adults. [Table 1] shows the personal and housing characteristics of the study sample. The sample included 714 males (74.4%) and 246 females (25.6%). The age ranged from 20 years to 95 years, with an average of 39.43 ± 14.63 years and a median of 36 years. The majority were secondary and higher educated (585, 60.9%). Illiterate were few (142, 14.8%). The most frequent occupations were office workers (333, 34.7%) and manual workers (204, 21.3%). Ever smoked were 30.5% (293), and obese and overweight were 68.1% (654).
|Table 1: Personal and housing characteristics of the study sample (960) in Aseer region, southwestern Saudi Arabia|
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Regarding altitude, the sample included 446 persons from high-altitude areas (47.5%), and 514 from low-altitude areas (53.5%). As far as rural-urban differences, the study included 492 adults from urban areas (51.3%) and 468 from rural areas (48.7%).
The majority of the samples were living in concrete houses (734, 76.5%) and the rest were living in traditional houses (226, 23.5%). The majority had electricity (949, 98.9%) and had no animals at their houses (618, 64.4%).
Prevalence of adult bronchial asthma
The present study showed that 184 adults reported having wheeze in the past 12 months when not having a cold giving a prevalence rate of BA of 19.2% (95% CI: 16.72–21.80). The prevalence of BA among males amounted to 18.3% (95% CI: 15.57–21.39) and among females amounted to 21.5% (95% CI: 16.57–27.21). The presence of an overlap in the 95% CI in males and females, indicated a nonsignificant statistical difference by gender.
Factors associated with adult bronchial asthma
[Table 2] shows the univariate and multivariable analysis of personal and environmental outdoor and indoor factors associated with BA. In multivariable analysis, some factors were found to be significantly associated with BA. Adults living at low-altitude areas had significantly more risk to develop BA compared to those living at high-altitude areas (aOR = 1.51, 95% CI: 1.04–2.21). Those living in rural areas (aOR = 1.58, 95% CI: 1.12–2.23), using analgesics (aOR = 1.52, 95% CI: 1.06–2.20), and living near heavy trucks traffic streets (aOR = 1.67, 95% CI: 1.13–2.46) had high risk to develop BA. Having cats in the house was found also as a significant factor for BA (aOR = 2.27, 95% CI: 1.30–5.94). Similarly, adults aged 55–64-year-old (aOR = 1.94, 95% CI: 1.02–3.69) were also at high risk.
|Table 2: Univariate and multivariable analysis of personal and environmental outdoor and indoor factors associated with adult asthma in Aseer region, southwestern Saudi Arabia|
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| Discussion|| |
Local reports suggest that the prevalence of BA is increasing in southwestern SA. The present study in Aseer region showed that 184 adults reported having wheeze in the past 12 months giving a prevalence rate of BA of 19.2% (95% CI: 16.72–21.80). A study investigating the prevalence of asthma among 16–18 years adolescents attending high schools in the city of Riyadh, utilizing the ISAAC questionnaire tool (similar to our study) found a comparable prevalence of wheeze during the past 12 months of 18.5%. Another study using the ECRHS questionnaire performed in Riyadh among Saudi patients aged 20–44 years found similarly a prevalence of wheezing in the past 12 months of 18.2%.
A meta-analysis on the variation in the prevalence of asthma in different regions in SA showed an elevation in the BA prevalence from 1990 to 2000 with steadiness in the prevalence of asthma since 2000. The pooled weighted prevalence rate of asthma was 14.3% (95% CI: 13.4–15.2).
In other countries, high figures were also reported among adults in Kuwait (15%), Sudan (15.5%), and Qatar (19.8%). Similarly, in other western countries, a prevalence of “wheezing symptoms” of 74.4, 254.8, and 123.4/1000 adults in Ukraine, Kazakhstan, and Azerbaijan, was found, respectively. A study in India found a prevalence of BA of 9.9% (95% CI = 7.53%–12.27%).
In the present study, the following factors were significantly associated with BA in adults; living in low-altitude areas, being in rural areas, using analgesics, residing near heavy trucks traffic streets, having cats in the house, and being aged 55–64-year-old.
Our results indicated that living in low-altitude areas was associates with a higher prevalence of BA as compared to high-altitude areas. This observation was previously reported in our region  and noted in other parts of the world. This may be explained by the lower allergenic potential in higher altitudes. It is believed that allergens density may differ by altitude level, which may impact climate features in a region and therefore, impact bronchial sensitization. While adverse effects of high-altitude living were reported for asthmatic children in the tropics, beneficial effects and treatment gains have been cited for adults living in high altitudes. The later may be comparable to our situation in Aseer region, where the high-altitude climate is similar or approaches temperate regions.
The present study found that living in rural areas was significantly associated with BA in adults. Rural-urban differences have been observed worldwide  and not withstanding SA. Factors that influence the disparity of asthma prevalence in rural versus urban are wide ranging and they include urbanization itself with indoors living and its environmental factors being the most important. In this respect, sensitization elements such as smoking, indoor air pollution, humidity, increased the use of analgesics, the use of floor carpeting, the presence of house dust mites, and other factors associated with urbanization. However, in our study, multivariate analysis of our data revealed a different situation with people living in rural areas showing increased sensitization to BA. The aeroallergen potential is greater and an important factor in the rural environment.
In multivariable analysis, the present study found that using analgesics was significantly associated with BA in adults. The adverse effects of the use of analgesics in asthmatics are well reported. The culprits are aspirins, paracetamol, and other nonsteroidal anti-inflammatory drugs. The use of the anti-inflammatory agents in exacerbation of BA in individuals with mild asthma and their role in the etiology of BA in adults is not very well understood. The use of aspirin has been implicated, and a number of hypothesis has been put forward. Similar arguments have been put forward with regard to the use of acetaminophen (paracetamol) in both children and adults.
The present study showed that residing near heavy trucks traffic streets (as a proxy of outdoor pollution) was a significant factor associated with BA in adults. There is now considerable evidence that traffic and outdoor pollution are important factors in new set asthma as well as exacerbating preexisting asthma. Particulate matters such as diesel exhaust particles, road dust, tire wear, and brake wear, and gaseous emissions including nitrogen oxides are all implicated. This may be explained by the possible interaction of outdoor air pollutants with the respiratory tract and the immune system.
The present study showed that having cats was significantly associated with BA in adults. Although it has previously been reported worldwide that the presence of cats and dogs in and around the house is associated with increased prevalence of asthma in children; nonetheless, this association was not clear for adults. This concept has recently been challenged, and indeed such association has been demonstrated. However, such notion should be counterbalanced with studies which propose a protective effect of exposure to cats and dogs as pets in earlier childhood, a concept not far removed from the hygiene hypothesis with regards to infection.
In multivariable analysis, the present study found that adults aged 55–64-year-old were significantly at risk to have BA. This finding is in agreement with previous reports indicating an association of asthma with older age and citing asthma morbidity in people over 55 years of age. Of note is that a specific asthma phenotype termed “Geriatric asthma” is now being ascribed to people of older age.
Limitations of the study are mostly related to two issues; the inclusion of adult persons attending PHCCs and the use of the history of a wheeze during the past 12 months as a proxy of BA. They may have resulted in an overestimation of the true prevalence of asthma.
| Conclusion|| |
One out of each five adults in Aseer region suffers from BA. The following factors are significantly associated with BA in adults; living in low-altitude areas, being in rural areas, using analgesics, residing near heavy trucks traffic streets, having cats in the house, and being aged 55–64-year-old. There is an urgent need to improve asthma control programs at the primary health-care level, particularly at rural and at low-altitude areas, and more focus should address the elders. In addition, enhancing community-based health promotion programs tackling the modifiable factors of BA as misuse of analgesics, outdoor pollution, cats in and around houses are needed. There is still continuous recommendation to continue epidemiological studies and nationwide research in this field.
The authors are grateful to Aseer General Directorate of Health Affairs and King Khalid University for their unlimited support.
Financial support and sponsorship
This study was financially supported by King Abdelaziz City for Science and Technology (AL-35-90).
Conflicts of interest
There are no conflicts of interest.
| References|| |
Moradi-Lakeh M, El Bcheraoui C, Daoud F, Tuffaha M, Kravitz H, Al Saeedi M, et al.
Prevalence of asthma in Saudi adults: Findings from a national household survey, 2013. BMC Pulm Med 2015;15:77.
Al Ghobain MO, Algazlan SS, Oreibi TM. Asthma prevalence among adults in Saudi Arabia. Saudi Med J 2018;39:179-84.
Alsubaiei ME, Cafarella PA, Frith PA, McEvoy RD, Effing TW. Factors influencing management of chronic respiratory diseases in general and chronic obstructive pulmonary disease in particular in Saudi Arabia: An overview. Ann Thorac Med 2018;13:144-9.
] [Full text]
Khawaji A, Basudan A, Moafa A, Faqihi M, Alhazmi M, Mahnashi T, et al
. Epidemiology of bronchial asthma among children in Jazan Region, Saudi Arabia. Indian J Allergy Asthma Immunol 2017; 31:69-75. [Full text]
Al-Moamary MS, Alhaider SA, Idrees MM, Al Ghobain MO, Zeitouni MO, Al-Harbi AS, et al.
The Saudi initiative for asthma – 2016 update: Guidelines for the diagnosis and management of asthma in adults and children. Ann Thorac Med 2016;11:3-42.
] [Full text]
Al-Ghamdi BR, Mahfouz AA, Abdelmoneim I, Khan MY, Daffallah AA. Altitude and bronchial asthma in South-Western Saudi Arabia. East Mediterr Health J 2008;14:17-23.
Hijazi N, Abalkhail B, Seaton A. Asthma and respiratory symptoms in urban and rural Saudi Arabia. Eur Respir J 1998;12:41-4.
Alamoudi O. Prevalence of respiratory diseases in hospitalized patients in Saudi Arabia: A 5 years study 1996-2000. Ann Thorac Med 2006;1:76-80. [Full text]
Al Moamary MS. Health care utilization among chronic obstructive pulmonary disease patients and the effect of pulmonary rehabilitation. Med Princ Pract 2010;19:373-8.
BinSaeed AA. Asthma control among adults in Saudi Arabia. Study of determinants. Saudi Med J 2015;36:599-604.
Alqahtani JM, Asaad AM, Awadalla NJ, Mahfouz AA. Environmental determinants of bronchial asthma among Saudi school children in Southwestern Saudi Arabia. Int J Environ Res Public Health 2016;14. pii: E22.
Hijazi N, Abalkhail B, Seaton A. Diet and childhood asthma in a society in transition: A study in urban and rural Saudi Arabia. Thora×2000;55:775-9.
Al-Mazam A, Mohamed AG. Risk factors of bronchial asthma in Bahrah, Saudi Arabia. J Family Community Med 2001;8:33-9.
El Margoushy N, El Nashar M, Khairy H, El Nashar N, Mohamad HJ. Effect of air pollution, contamination and high altitude on bronchial asthma. Egyptian Journal of Hospital Medicine 2013;31:1-10.
Alshehri MA, Abolfotouh MA, Sadeg A, Al Najjar YM, Asindi AA, Al Harthi AM, et al.
Screening for asthma and associated risk factors among urban school boys in Abha city. Saudi Med J 2000;21:1048-53.
Nahhas M, Bhopal R, Anandan C, Elton R, Sheikh A. Prevalence of allergic disorders among primary school-aged children in Madinah, Saudi Arabia: Two-stage cross-sectional survey. PLoS One 2012;7:e36848.
Al Frayh AR, Shakoor Z, Gad El Rab MO, Hasnain SM. Increased prevalence of asthma in Saudi Arabia. Ann Allergy Asthma Immunol 2001;86:292-6.
Abudahish A, Bella H. Primary care physicians perceptions and practices on asthma care in Aseer region, Saudi Arabia. Saudi Med J 2006;27:333-7.
Lwanga SK, Lemeshow S. Sample Size Determination in Health Studies: A Practical Manual. Geneva: World Health Organization; 1991.
Israel E, El-Setouhy M, Gadalla S, Aoun el SA, Mikhail N, Mohamed MK. Water pipe (Sisha) smoking in cafes in Egypt. J Egypt Soc Parasitol 2003;33:1073-85.
Magzoub AA, Musa OA, Elsony AE, Alawad AO, Dawod OY. Validation of the modified international study of asthma and allergies in childhood questionnaire: Is wheeze alone enough for determination of asthma symptoms prevalence? Int J Med Sci Publ Health2017;6:775-9.
Pearce N, Sunyer J, Cheng S, Chinn S, Björkstén B, Burr M, et al.
Comparison of asthma prevalence in the ISAAC and the ECRHS. ISAAC Steering Committee and the European Community Respiratory Health Survey. International study of asthma and allergies in childhood. Eur Respir J 2000;16:420-6.
Wandalsen NF, Gonzalez C, Wandalsen GF, Solé D. Evaluation of criteria for the diagnosis of asthma using an epidemiological questionnaire. J Bras Pneumol 2009;35:199-205.
Al Ghobain MO, Al-Hajjaj MS, Al Moamary MS. Asthma prevalence among 16- to 18-year-old adolescents in Saudi Arabia using the ISAAC questionnaire. BMC Public Health 2012;12:239.
Mohamed Hussain S, Ayesha Farhana S, Mohammed Alnasser S. Time trends and regional variation in prevalence of asthma and associated factors in Saudi Arabia: A Systematic review and meta-analysis. Biomed Res Int 2018;2018:8102527.
Masjedi M, Ainy E, Zayeri F, Paydar R. Assessing the prevalence and incidence of asthma and chronic obstructive pulmonary disease in the Eastern Mediterranean region. Turk Thorac J 2018;19:56-60.
Nugmanova D, Sokolova L, Feshchenko Y, Iashyna L, Gyrina O, Malynovska K, et al.
The prevalence, burden and risk factors associated with bronchial asthma in commonwealth of independent states countries (Ukraine, Kazakhstan and Azerbaijan): results of the CORE study 2018; 18:110.
Lalu JS, Rakesh PS, Leelamoni K. Prevalence of bronchial asthma and factors associated with it among higher secondary school children in ernakulam district, Kerala, Southern India. J Family Med Prim Care 2017;6:311-5.
] [Full text]
Menz G. Effect of sustained high altitude on asthma patients. Expert Rev Respir Med 2007;1:219-25.
Duenas-Meza E, Torres-Duque CA, Correa-Vera E, Suárez M, Vásquez C, Jurado J, et al
. High prevalence of house dust mite sensitization in children with severe asthma living at high altitude in a tropical country. Pediatr Pulmonol 2018;53:1356-61.
Rijssenbeek-Nouwens LH, Fieten KB, Bron AO, Hashimoto S, Bel EH, Weersink EJ. High-altitude treatment in atopic and nonatopic patients with severe asthma. Eur Respir J 2012;40:1374-80.
Asher MI. Urbanisation, asthma and allergies. Thorax 2011;66:1025-6.
Jie Y, Isa ZM, Jie X, Ju ZL, Ismail NH. Urban vs. rural factors that affect adult asthma. Rev Environ Contam Toxicol 2013;226:33-63.
Oliveira M, Ribeiro H, Delgado L, Fonseca J, Castel-Branco MG, Abreu I. Outdoor allergenic fungal spores: Comparison between an urban and a rural area in Northern Portugal. J Investig Allergol Clin Immunol 2010;20:117-28.
Jenkins C, Costello J, Hodge L. Systematic review of prevalence of aspirin induced asthma and its implications for clinical practice. BMJ 2004;328:434.
Varghese M, Lockey RF. Aspirin-exacerbated asthma. Allergy Asthma Clin Immunol 2008;4:75-83.
Holgate ST. The acetaminophen enigma in asthma. Am J Respir Crit Care Med 2011;183:147-8.
Guarnieri M, Balmes JR. Outdoor air pollution and asthma. Lancet 2014;383:1581-92.
Simoneti CS, Ferraz E, Menezes MB, Icuma TR, Vianna EO. Cat ownership is associated with increased asthma prevalence and dog ownership with decreased spirometry values. Braz J Med Biol Res 2018;51:e7558.
Salo PM, Zeldin DC. Does exposure to cats and dogs decrease the risk of allergic sensitization and disease? J Allergy Clin Immunol 2009;124:751-2.
Gillman A, Douglass JA. Asthma in the elderly. Asia Pac Allergy 2012;2:101-8.
Battaglia S, Benfante A, Spatafora M, Scichilone N. Asthma in the elderly: A different disease? Breathe (Sheff) 2016;12:18-28
[Table 1], [Table 2]
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