title: The impact of rural residency on the expression and outcome of systemic lupus erythematosus: data from a multiethnic Latin American cohort.
abstract: OBJECTIVE
  The objective of this paper is to examine the role of place of residency in the expression and outcomes of systemic lupus erythematosus (SLE) in a multi-ethnic Latin American cohort.
  
  
  METHODS
  SLE patients (< two years of diagnosis) from 34 centers constitute this cohort. Residency was dichotomized into rural and urban, cut-off: 10,000 inhabitants. Socio-demographic, clinical/laboratory and mortality rates were compared between them using descriptive tests. The influence of place of residency on disease activity at diagnosis and renal disease was examined by multivariable regression analyses.
  
  
  RESULTS
  Of 1426 patients, 122 (8.6%) were rural residents. Their median ages (onset, diagnosis) were 23.5 and 25.5 years; 85 (69.7%) patients were Mestizos, 28 (22.9%) Caucasians and 9 (7.4%) were African-Latin Americans. Rural residents were more frequently younger at diagnosis, Mestizo and uninsured; they also had fewer years of education and lower socioeconomic status, exhibited hypertension and renal disease more frequently, and had higher levels of disease activity at diagnosis; they used methotrexate, cyclophosphamide pulses and hemodialysis more frequently than urban patients. Disease activity over time, renal damage, overall damage and the proportion of deceased patients were comparable in rural and urban patients. In multivariable analyses, rural residency was associated with high levels of disease activity at diagnosis (OR 1.65, 95% CI 1.06-2.57) and renal disease occurrence (OR 1.77, 95% CI 1.00-3.11).
  
  
  CONCLUSIONS
  Rural residency associates with Mestizo ethnicity, lower socioeconomic status and renal disease occurrence. It also plays a role in disease activity at diagnosis and kidney involvement but not on the other end-points examined.
authors.affiliation: Department of Autoimmune Diseases, Institut Clínic de Medicina i Dermatologia, Hospital Clínic, Spain. gponsestel@hotmail.com
authors.forename: G J
authors.initials: GJ
authors.lastname: Pons-Estel
authors.forename: V
authors.initials: V
authors.lastname: Saurit
authors.forename: G S
authors.initials: GS
authors.lastname: Alarcón
authors.forename: L
authors.initials: L
authors.lastname: Hachuel
authors.forename: G
authors.initials: G
authors.lastname: Boggio
authors.forename: D
authors.initials: D
authors.lastname: Wojdyla
authors.forename: J L
authors.initials: JL
authors.lastname: Alfaro-Lozano
authors.forename: I García
authors.initials: IG
authors.lastname: de la Torre
authors.forename: L
authors.initials: L
authors.lastname: Massardo
authors.forename: M H
authors.initials: MH
authors.lastname: Esteva-Spinetti
authors.forename: M
authors.initials: M
authors.lastname: Guibert-Toledano
authors.forename: L A Ramirez
authors.initials: LA
authors.lastname: Gómez
authors.forename: L T Lavras
authors.initials: LT
authors.lastname: Costallat
authors.forename: M J Sauza
authors.initials: MJ
authors.lastname: Del Pozo
authors.forename: L H
authors.initials: LH
authors.lastname: Silveira
authors.forename: F
authors.initials: F
authors.lastname: Cavalcanti
authors.forename: B A
authors.initials: BA
authors.lastname: Pons-Estel
mesh_terms: D000328:Adult; D000367:Age Factors; D044467:American Indian or Alaska Native / Q000706:statistics & numerical data; D044383:Black People / Q000706:statistics & numerical data; D016009:Chi-Square Distribution; D015897:Comorbidity; D003520:Cyclophosphamide / Q000627:therapeutic use; D018450:Disease Progression; D004522:Educational Status; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data; D054625:Healthcare Disparities / Q000208:ethnology; D006801:Humans; D006973:Hypertension / Q000208:ethnology; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007843:Latin America / Q000453:epidemiology; D016015:Logistic Models; D008137:Longitudinal Studies; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis / Q000208:ethnology* / Q000628:therapy; D008181:Lupus Nephritis / Q000208:ethnology; D008297:Male; D017057:Medically Uninsured / Q000208:ethnology; D008727:Methotrexate / Q000627:therapeutic use; D015999:Multivariate Analysis; D016017:Odds Ratio; D011379:Prognosis; D044469:Racial Groups / Q000706:statistics & numerical data*; D006435:Renal Dialysis; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D012307:Risk Factors; D012423:Rural Health / Q000706:statistics & numerical data*; D012959:Socioeconomic Factors; D013997:Time Factors; D014504:Urban Health / Q000706:statistics & numerical data*; D044465:White People; D055815:Young Adult
chemical_list: D007166:Immunosuppressive Agents; D003520:Cyclophosphamide; D008727:Methotrexate