Occupational and environmental scleroderma. Systematic review and meta-analysis.

Area of Science:

• Rheumatology and Environmental Health

Background:

• The exact causes of systemic sclerosis (SSc) are unknown, but occupational and environmental exposures are suspected contributors.
• Identifying specific environmental risk factors is crucial for understanding SSc etiology and prevention.

Purpose of the Study:

• To conduct a comprehensive meta-analysis of existing studies on the association between occupational and environmental exposures and systemic sclerosis.
• To identify specific substances implicated in the pathogenesis of SSc.

Main Methods:

• A systematic literature review and meta-analysis were performed using MEDLINE and SCOPUS databases (1960-2014).
• Search terms included "systemic," "scleroderma," and "systemic sclerosis/chemically induced" [MesH].
• Study quality was assessed using the Newcastle-Ottawa Scale, and data were analyzed using the inverse variance-weighted method.

Main Results:

• Silica exposure was associated with a significantly increased risk of SSc (OR 2.81 in case-control studies; RR 17.52 in cohort studies).
• Solvent exposure also showed a significant association with SSc (OR 2.00 in case-control studies).
• Epoxy resins showed a significant association (OR 2.97), while breast implants, pesticides, and welding fumes had non-significant associations in this meta-analysis.

Conclusions:

• Silica and solvents are the most probable environmental factors linked to the development of systemic sclerosis.
• The widespread use of solvents poses a broader risk to the general population compared to silica, which is often linked to specific occupations.