title: Childhood socioeconomic factors and perinatal characteristics influence development of rheumatoid arthritis in adulthood.
abstract: BACKGROUND
  Rheumatoid arthritis (RA) has been associated with lower socioeconomic status (SES), but the reasons for this are not known.
  
  
  OBJECTIVE
  To examine childhood SES measures, SES trajectory and other perinatal factors in relation to RA.
  
  
  METHODS
  The sample included 50 884 women, aged 35-74 (84% non-Hispanic white) enrolled 2004-9 in a US national cohort study. In baseline questionnaires, cases (N=424, 0.8%) reported RA diagnosis after age 16, ever use of disease-modifying antirheumatic drugs or steroids for RA and ≥6 weeks bilateral joint swelling. Childhood SES measures are presented as OR and 95% CI adjusted for age and race/ethnicity. Analyses of perinatal factors also adjusted for childhood SES, and joint effects of childhood and adult SES and smoking exposures were evaluated.
  
  
  RESULTS
  Patients with RA reported lower childhood household education (<12 years vs college degree; OR=1.7; 95% CI 1.1 to 2.5), food insecurity (OR=1.5, 95% CI 1.1 to 2.0) and young maternal age (<20 vs 20-34 years; OR=1.7, 95% CI 1.2 to 2.5), with a trend (p<0.0001) for increasing number of adverse factors (OR=3.0; 95% CI 1.3 to 7.0; 4 vs 0 factors) compared with non-cases. Low birth weight (<2500 g) [corrected] and preconception paternal smoking were independently associated with RA. Together, lower childhood SES and adult education (<college degree) were associated with RA (interaction p=0.03), with a joint effect magnitude similar to a history of paternal and adult smoking.
  
  
  CONCLUSIONS
  RA was associated with low childhood SES sustained into adulthood, with cumulative effects across multiple measures, suggesting the importance of other unmeasured factors linking SES and RA.
authors.affiliation: Epidemiology Branch, Division of Intramural Research, National Institute of Environmental Health Sciences, Durham, NC 27599, USA. Parks1@mail.nih.gov
authors.forename: Christine G
authors.initials: CG
authors.lastname: Parks
authors.forename: Aimee A
authors.initials: AA
authors.lastname: D'Aloisio
authors.forename: Lisa A
authors.initials: LA
authors.lastname: DeRoo
authors.forename: Kirstin
authors.initials: K
authors.lastname: Huiber
authors.forename: Lisa G
authors.initials: LG
authors.lastname: Rider
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Miller
authors.forename: Dale P
authors.initials: DP
authors.lastname: Sandler
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000209:etiology*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012307:Risk Factors; D012959:Socioeconomic Factors; D055815:Young Adult