Evaluation of Work-Related Symptoms by Job Exposure Matrix in Chronic Pulmonary Diseases - A Cross-sectional Study

Despite the high prevalence of occupational airway disorders, they are usually underestimated by physicians. This study designed to study the prevalence of work-related symptoms (WRS) and their association with occupational exposure in outpatient pulmonary clinics.

Adults with more than one year of lower respiratory symptoms were included. Retired patients, housewives and those unable to perform spirometry were excluded. Demographic, anthropometric and medical data were documented. The Persian version of National institute for health and safety respiratory questionnaire was used to classify job titles. WRS were defined as 2 (or more) positive questions with improvement of symptoms on days off work. Job exposure matrix (JEM) was used for classifying the type of occupational exposure into one of three categories: high molecular weight (HKW), low molecular weight (LMW) and mixed.

A total of 250 patients (69% male) with mean (±SD) age of 40 (±11.6) years, 178 cases of asthma and 59 chronic obstructive pulmonary disease (COPD) cases entered. Occupational exposure was seen in 51.2% of patients (26, 51 and 51 cases with HMW, LMW and mixed, respectively). WRS were lower in those who exercised regularly (24.6% vs. 39.4%) and higher in those with eczema (62.5% vs. 33.6%). Eczema had an odds ratio (OR) of 4.13 (95% CI 1.3 to 12.9, P = 0.01). Exposure to LMW almost tripled the risk of WRS (OR: 2.9, 95% CI: 1.4 to 5.9, P = 0.003) in our patients.

Pulmonologists are firmly advised to take their patients' occupational and vocational exposures into consideration for treatment plans, especially in those with positive history of eczema and exposure to LMW.