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Several Farming Tasks Associated with RA

Occup Environ Med; ePub 2019 Feb 13; Parks, et al

Recent findings suggest several agricultural tasks and exposures may contribute to development of rheumatoid arthritis (RA). Researchers investigated non-pesticide agricultural exposures in relation to RA in licensed pesticide applicators (n=27,175, mostly male farmers) and their spouses (n=22,231) in the Agricultural Health Study (AHS) cohort (1993–1997) who completed at least 1 follow-up survey through 2015. Incident RA cases (n=229 applicators and 249 spouses) were identified based on self-report confirmed by use of disease-modifying antirheumatic drugs or medical records.

  • Overall, RA was associated with regularly applying chemical fertilizers (HR=1.50), using non-gasoline solvents (HR=1.40), and painting (HR=1.26).
  • In older applicators (>62 years), RA was associated with driving combines (HR=2.46) and milking cows (HR=2.56).
  • In younger participants (≤62 years), RA was inversely associated with raising animals as well as crops (HR=0.68 vs crops only).
  • Associations with specific crops varied by age: some (eg, hay) were inversely associated with RA in younger participants, while others (eg, alfalfa) were associated with RA in older participants.
Citation:

Parks CG, Meyer A, Beane Freeman LE, Hofmann J, Sandler DP. Farming tasks and the development of rheumatoid arthritis in the agricultural health study. [Published online ahead of print February 13, 2019]. Occup Environ Med. doi:10.1136/oemed-2018-105361.

Commentary:

This study reported that several agricultural tasks might contribute to the development of rheumatoid arthritis (RA). Non-pesticide agricultural exposures were studied including (n=27,175, mostly male farmers) and their spouses (n=22,231). Age differences and type of crops grown had an impact on the study’s findings. Researchers discovered that RA was associated with the regular application of chemical fertilizers (HR=1.50), use of non-gasoline solvents (HR=1.40), and exposure to paint (HR=1.26). RA was also linked with driving combines (HR=2.46) and milking cows (HR=2.56). In younger subjects, RA was inversely linked to raising animals as well as crops (HR=0.68 vs crops only). Also, in younger participants, hay was associated with RA while in older participants, alfalfa was linked to RA.—Harold E. Paulus, M.D.; Emeritus Professor; University of California, Los Angeles; Division of Rheumatology.