Parks CG, et al. – The association between early life pesticide exposures and risk of adult onset rheumatoid arthritis (RA) was investigated. The possibility of a link between adult–onset RA and childhood exposures to residential and agricultural pesticides was highlighted in the findings.

Methods

• Researchers assessed childhood pesticide exposures in adult-onset RA in a national cohort of women ages 35–74 (enrolled 2004–2009) in the Sister Study.
• They compared cases (n = 424), reported at enrollment and confirmed by disease modifying anti-rheumatic drugs or steroid use for RA and ≥6 weeks bilateral joint swelling, to 48,919 non-cases.
• Data included pesticide use at the longest childhood residence through age 14, farm residence of ≥12 months with agricultural pesticide exposures through age 18, and maternal farm experience.
• In addition, odds ratios (OR) and 95% confidence intervals (CI) were adjusted for age, race/ethnicity, education, smoking, and childhood socioeconomic factors.

Results

• Findings demonstrated that RA cases reported more frequent (monthly+) and direct (personal) residential pesticide use in childhood (ORs ranging from 1.1 for infrequent/indirect to 1.8 for frequent/direct; P-trend = 0.013).
• Researchers observed that, compared to women with no residential farm history, odds of RA increased for those reporting a childhood-only farm residence with personal exposure to pesticides used on crops (OR = 1.8:95% CI: 1.1, 2.9) or livestock (OR = 2.0:95% CI: 1.2, 3.3).