Smoking, Urban Housing, Work-Aggravated Asthma Linked to Asthma Severity

Researchers have identified a strong association between asthma severity and modifiable environmental exposures, including smoking, urban housing, and work-aggravated asthma.

This cross-sectional observational study is published in the Journal of Asthma and Allergy.

A man outside an office building has a severe asthma attack | Liubomir - stock.adobe.com

“Better understanding of the mechanisms of asthma holds the key to refining its management,” the researchers of the study wrote. “In particular, the factors contributing to asthma severity are not well known beyond the role of persistent airway inflammation.”

The researchers utilized the Asthma Severity Scoring System (ASSESS), which globally quantifies asthma severity by integrating symptom control from the Asthma Control Test (ACT) score, the occurrence of exacerbations in the past 6 months, lung function evaluated by forced expiratory volume per 1 second (FEV₁), and therapeutic load assessed similar to 2016 Global Initiative for Asthma (GINA) levels.

In the current study, the researchers analyzed ASSESS scores with atopy and allergy, as well as modifiable markers of environmental exposure, to identify factors associated with asthma severity.

The researchers collected data from the France Asthma Severe (FASE-CPHG) study between May 2016 and June 2017, including 1377 patients who visited a pulmonologist among 104 French hospital pulmonology departments. The data also included information on social and demographic characteristics, triggers of asthma symptoms, medical history, and comorbidities.

Additionally, the researchers collected information on lung function testing data, blood cell counts, skin prick tests for aeroallergens, allergen-specific immunoglobulin (IgE), treatments, and a self-administered questionnaire. The questionnaire included the ACT score, the number of unscheduled visits, and the number of asthma exacerbations requiring oral corticosteroids or hospitalization in the previous 12 months.

Of the total initial patients in the FASE-CPHG study, 948 were included in the analysis. Among these patients, 592 were women, of which 47% had severe asthma. Additionally, 491 (52%) patients had at least 1 positive aeroallergen skin prick test, and 525 (55%) had at least 1 allergic disease among atopic dermatitis, chronic rhinitis, and food allergy.

The mean (SD) ASSESS score was 11.2 (3.4), with higher ASSESS scores for female sex, secondary or lower education, unemployed occupational status, smoking, work-aggravated asthma, and urban housing. Higher ACT scores were identified for female sex (0.47; 95% CI, .22-0.72; P < .001), unemployed occupational status (0.44; 95% CI, 0.12-0.75: P = .006), smoking (0.01; 95% CI, 0.00-0.02; P = .004), work-aggravated asthma (0.53; 05% CI, 0.17-0.88; P = .004), and urban housing (0.39; 95% CI, 0.16-0.63; P = .001), well as high therapeutic load for secondary or lower education (1.47; 95% CI, 1.04-2.09; P = .029).

No associations were found between the ASSESS score and allergic diseases, aeroallergen-specific skin prick tests and IgEs, or blood eosinophil counts.

However, the researchers acknowledged some limitations to the study. First, patients included in the study were adults. Therefore, the study is not generalizable to pediatric or young adult populations. Second, the underlying mechanisms of the association between secondary or lower education and asthma severity is unclear and may be attributed to other factors that increased asthma severity in this demographic, such as higher stress. Furthermore, there was no information on household income or accommodation conditions, as well as comprehensive comorbidity data.

Despite these limitations, the researchers believe the ASSESS can be used to identify markers of asthma severity, identifying smoking, urban housing, and patient-reported work-aggravated asthma as modifiable factors associated with asthma severity.

“The main strength of this study lies in the use of the ASSESS score, which allows the compilation of several domains of asthma severity into a single metric,” wrote the researchers. “The finding that all components of the ASSESS score were associated with patient characteristics suggests the potential inadequacy of relying solely on control scores or the number of exacerbations to assess asthma severity.”

Reference

Chevereau-Choquet M, Thoreau B, Taillé C, Marchand-Adam S, et al. Smoking, urban housing and work-aggravated asthma are associated with asthma severity in a cross-sectional observational study. J Asthma Allergy. 2024;17:69-79
https://doi.org/10.2147/JAA.S424546