Duration of exposure and educational level as predictors of occupational respiratory symptoms among adults in Ethiopia: A systematic review and meta-analysis

INTRODUCTION: Occupational respiratory symptoms are manifestations of respiratory diseases because of exposure to dust or chemicals such as asbestos, silicon and aluminium in the workplace like cement factory, tannery, textile and/or street sweeping, all of which affect the health condition and productivity. In Ethiopia, several primary studies were conducted regarding the magnitude of occupational respiratory symptoms with the prevalence of 68.89% in street sweepers and associated factors with inconsistent results. This meta-analysis aimed to pool the prevalence of respiratory symptoms and their associated factors among Ethiopian adults working in different workplaces. METHODS: PubMed, African Journals Online, Google Scholar, Cochrane Library and Direct Google were systematically searched to identify primary studies. Two authors performed data abstraction and quality assessment for each included study independently. Cochran’s Q-statistic and I(2) (I-squared) statistic were used to check heterogeneity. DerSimonian and Laird random-effects models were used to estimate the pooled prevalence and associated factors of respiratory symptoms. Publication bias was checked by funnel plot and Egger’s test, and also sensitivity analyses were performed. RESULTS: Ten primary studies with 3441 study participants were included for the narrative synthesis and meta-analysis of the pooled prevalence of occupational respiratory symptoms. The pooled prevalence of overall occupational respiratory symptom was 54.58% (95% CI: 45.37–63.79). Dry cough was the most encountered respiratory symptom [34.93, 95% CI: 29.52–40.35], followed by breathlessness [28.67%, 95% CI: 20.13–37.22]. Work experience of over 5 years [OR = 2.24, 95% CI: 1.21–4.16] and educational level of Grade 8 and lower [OR = 1.28, 95% CI: 1.06–1.55] were significantly associated with occupational respiratory symptoms. CONCLUSION: In this review, the pooled prevalence of occupational respiratory symptoms was high. The findings of this study dictate the need for the implementation of workplace safety measures. Special attention is required to employees with lower educational level and longer duration of work experience. PROSPERO REGISTRATION: CRD42020176826