title: Welding, longitudinal lung function decline and chronic respiratory symptoms: a systematic review of cohort studies.
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 s (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 nonwelders was -9.0 mL · year(-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 · year(-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 · year(-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.
authors.affiliation: Imperial College (National Heart and Lung Institute), London.
authors.forename: Joanna
authors.initials: J
authors.lastname: Szram
authors.forename: Susie J
authors.initials: SJ
authors.lastname: Schofield
authors.forename: Martin P
authors.initials: MP
authors.lastname: Cosgrove
authors.forename: Paul
authors.initials: P
authors.lastname: Cullinan
mesh_terms: D000395:Air Pollutants, Occupational; D001991:Bronchitis / Q000209:etiology / Q000503:physiopathology; D015331:Cohort Studies; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008670:Metals; D009784:Occupational Diseases / Q000453:epidemiology / Q000503:physiopathology; D016273:Occupational Exposure; D016272:Occupational Health; D012120:Respiration Disorders / Q000453:epidemiology* / Q000209:etiology*; D012129:Respiratory Function Tests; D012907:Smoking / Q000009:adverse effects; D014896:Welding
chemical_list: D000395:Air Pollutants, Occupational; D008670:Metals