Abstract

Epidemiological studies indicate that cleaners are at increased risk of asthma. Many cleaners work in precarious employment conditions potentially leading to stress, a known risk factor for asthma. Therefore, we aimed to analyse whether the high prevalence of asthma in cleaners might partly be explained by psychosocial working conditions.

The study population of this cross-sectional study included 199 cleaners employed at regional public health services in Puno province (Peru). They were compared to 79 unexposed workers from Lima, Peru (response 83%). Both groups answered the short version of the European Working Condition Survey and a modified version of the European Community Respiratory Health screening questionnaire. After multiple imputation, the association between type of job, employment conditions, job strain and control, social support, bullying, violence, distress and asthma (wheeze without cold or use of asthma medication) was assessed.

The 12-months prevalence of asthma was 22% among cleaners compared to 5% among unexposed workers (pChi2 = 0.001). Cleaners were more likely than unexposed workers to be female, be non-smokers, work with temporary contracts and as subcontractors, have a high employment insecurity, high strain working conditions and low social support (all pChi2 < 0.05). Twenty six percent vs. 10% reported a high bullying score; 39% vs. 8% had experienced violence during the 12-months prior to the study (both pChi2 < 0.001). High bullying score (adjusted Odds Ratio 5.6; 95% Confidence Interval 1.5–21.4) and violence at the workplace (2.4; 1.1–5.4) were main predictors of asthma. Taking these factors into account, being a cleaner was no longer statistically significantly associated with the outcome (3.5; 0.9–13.8).

The poor psychosocial working conditions of cleaners may partly explain the high prevalence of asthma in this group. The underlying mechanism might be a stress-induced inflammatory immune response.