Work-exacerbated asthma and occupational asthma: do they really differ?
Lemière-C; Boulet-L-P; Chaboillez-S; Forget-A; Chiry-S; Villeneuve-H; Prince-P; Maghni-K; Kennedy-WA; Blais-L
J Allergy Clin Immunol 2013 Mar; 131(3):704-710.e3
BACKGROUND: Although work-exacerbated asthma (WEA) is a prevalent condition likely to have an important societal burden, there are limited data on this condition. OBJECTIVES: The aims of this study were (1) to compare the clinical, functional, and inflammatory characteristics of workers with WEA and occupational asthma (OA) and (2) compare health care use and related costs between workers with WEA and OA, as well as between workers with work-related asthma (WRA; ie, WEA plus OA) and those with non-work-related asthma (NWRA) in a prospective study. METHODS: We performed a prospective observational study of workers with and without WRA with a 2-year follow-up. The diagnosis of OA and WEA was based on the positivity and negativity of results on specific inhalation challenges, respectively. RESULTS: One hundred fifty-four subjects were enrolled: 53 with WEA, 68 with OA, and 33 control asthmatic subjects (NWRA). WEA was associated with more frequent prescriptions of inhaled corticosteroids (odds ratio [OR], 4.4; 95% CI, 1.4-13.6; P = .009), a noneosinophilic phenotype (OR, 0.3; 95% CI, 0.1-0.9; P = .04), a trend toward a lower FEV1 (OR, 0.9; 95% CI, 0.9-1.0; P = .06), and a higher proportion of smokers (OR, 2.5; 95% CI, 0.96-9.7; P = .06) than the diagnosis of OA. The health care use of WRA and related costs were 10-fold higher than those of NWRA. CONCLUSION: Workers with WEA appeared to have features of greater asthma severity than workers with OA. In contrast with OA, WEA was associated with a noneosinophilic phenotype. Both OA and WEA were associated with greater health care use and 10-fold higher direct costs than NWRA.
Humans; Men; Women; Respiration; Respiratory-system-disorders; Pulmonary-function; Pulmonary-disorders; Pulmonary-system; Pulmonary-system-disorders; Physiopathology; Age-groups; Inhalants; Statistical-analysis;
Author Keywords: Cost; health care use; occupational asthma; sputum eosinophils; work-exacerbated asthma
Catherine Lemière, MD, MSc, Department of Chest Medicine, Sacré-Coeur Hospital, 5400 Gouin West, Montreal, Quebec H4J 1C5, Canada
Journal of Allergy and Clinical Immunology
Hôpital du Sacré-Coeur de Montréal