Ever and cumulative occupational exposure and lung function decline in longitudinal population-based studies: A systematic review and meta-analysis

Abstract

Objectives Adverse occupational exposures can accelerate age-related lung function decline. Some longitudinal population-based studies have investigated this association. This study aims to examine this association using findings reported by longitudinal population-based studies. Methods Ovid Medline, PubMed, Embase, and Web of Science were searched using keywords and text words related to occupational exposures and lung function and 12 longitudinal population-based studies were identified using predefined inclusion criteria. The quality of the studies was assessed using the Newcastle-Ottawa Scale. Lung function decline was defined as annual loss of forced expiratory volume in 1 s (FEV 1), forced vital capacity (FVC) or the ratio (FEV 1 /FVC). Fixed and random-effects meta-analyses were conducted to calculate pooled estimates for ever and cumulative exposures. Heterogeneity was assessed using the I 2 test, and publication bias was evaluated using funnel plots. Results Ever exposures to gases/fumes, vapours, gases, dusts, fumes (VGDF) and aromatic solvents were significantly associated with FEV 1 decline in meta-analyses. Cumulative exposures for these three occupational agents observed a similar trend of FEV 1 decline. Ever exposures to fungicides and cumulative exposures to biological dust, fungicides and insecticides were associated with FEV 1 decline in fixed-effect models only. No statistically significant association was observed between mineral dust, herbicides and metals and FEV 1 decline in meta-analyses. Conclusion Pooled estimates from the longitudinal population-based studies have provided evidence that occupational exposures are associated with FEV 1 decline. Specific exposure control and respiratory health surveillance are required to protect the lung health of the workers.