Occupational exposures and sarcoidosis: a rapid review of the evidence

Background Sarcoidosis is a rare, multisystem, inflammatory condition associated with the formation of granulomas. Diagnosis can be challenging because of non-specific symptoms complicating epidemiological investigations of its aetiology. Despite research efforts, a review of the current state of the evidence is needed.Aims To assess the evidence for an association between occupational exposures and the development of sarcoidosis. To determine if workers in any occupation are at a greater risk of developing sarcoidosis.Methods This rapid review follows the methodology suggested by the World Health Organization. Two electronic databases were systematically searched until April 2022. The methodological quality of the studies was critically appraised, and a best-evidence approach was used to synthesize the results.Results Titles and abstracts of 2916 articles were screened, with 67 full-text articles reviewed for eligibility. Among the 13 studies eligible for this review, none were of high quality (i.e. low risk of bias). Six studies exploring the association between sarcoidosis and a range of occupations and exposures, and one previous systematic review were of low quality reporting inconsistent findings. Six studies examined the risk of sarcoidosis associated with occupational silica exposure, two of which were of acceptable quality. Overall, the study methodologies and results were inadequate to support causal relationships.Conclusions There is limited evidence of acceptable methodological quality to assess the risk of sarcoidosis associated with occupational exposures. There is a growing body of research examining occupational exposure to silica and sarcoidosis. Additional high-quality confirmatory research is needed. A rapid review was conducted to determine the level of evidence for an association between occupational exposures and the development of sarcoidosis. Following a critical appraisal of the scientific literature, the overall results showed that positive evidence of a causal association between occupational exposures and sarcoidosis is lacking. Despite recent advances in the scientific evidence examining occupational (e.g. silica), environmental and genetic risk factors, the aetiology of sarcoidosis remains unknown.