Abstract
While the acute respiratory risks of welding are well characterised, more chronic effects – including those on lung function – are less clear. We carried out a systematic review of published longitudinal studies of lung function decline in welders.
Original cohort studies documenting two or more sequential measurements of lung function were reviewed. Meta-analysis was carried out on studies with suitable data on forced expiratory volume in 1 second (FEV1).
Seven studies were included; their quality (measured on the Newcastle-Ottawa scale) was good, although exposure assessment was limited and the studies showed significant heterogeneity. Five had data suitable for meta-analysis; the pooled estimate of the difference in FEV1 decline between welders and non-welders was −9.0 mL·yr−1 (95% CI −22.5, 4.5, p=0.193). The pooled estimates of difference in annual FEV1 decline between welders and referents who smoked was −13.7 mL·yr−1 (95% CI −33.6, 6.3, p=0.179). For welders and referents who did not smoke the estimated difference was −3.8 mL·yr−1 (95% CI −20.2, 12.6, p=0.650). Symptom prevalence data were mainly narrative; smoking appeared to have the greatest effect on symptom evolution.
Collectively, available longitudinal data on decline of lung function in welders and respiratory symptoms suggest a greater effect in those who smoke, supporting a focus on smoking cessation as well as control of fume exposure in this trade. Further prospective studies are required to confirm these findings.
- ERS