title: Spatial distribution of end-stage renal disease (ESRD) and social inequalities in mixed urban and rural areas: a study in the Bretagne administrative region of France.
abstract: BACKGROUND
  Several studies have investigated the implication of biological and environmental factors on geographic variations of end-stage renal disease (ESRD) incidence at large area scales, but none of them assessed the implication of neighbourhood characteristics (healthcare supply, socio-economic level and urbanization degree) on spatial repartition of ESRD. We evaluated the spatial implications of adjustment for neighbourhood characteristics on the spatial distribution of ESRD incidence at the smallest geographic unit in France.
  
  
  METHODS
  All adult patients living in Bretagne and beginning renal replacement therapy during the 2004-09 period were included. Their residential address was geocoded at the census block level. Each census block was characterized by socio-economic deprivation index, healthcare supply and rural/urban typology. Using a spatial scan statistic, we examined whether there were significant clusters of high risk of ESRD incidence.
  
  
  RESULTS
  The ESRD incidence was non-randomly spatially distributed, with a cluster of high risk in the western Bretagne region (relative risk, RR = 1.28, P-value = 0.0003). Adjustment for sex, age and neighbourhood characteristics induced cluster shifts. After these adjustments, a significant cluster (P = 0.013) persisted.
  
  
  CONCLUSIONS
  Our spatial analysis of ESRD incidence at a fine scale, across a mixed rural/urban area, indicated that, beyond age and sex, neighbourhood characteristics explained a great part of spatial distribution of ESRD incidence. However, to better understand spatial variation of ESRD incidence, it would be necessary to research and adjust for other determinants of ESRD.
authors.affiliation: EHESP Rennes, Sorbonne Paris Cité , Rennes , France.
authors.forename: Wahida
authors.initials: W
authors.lastname: Kihal-Talantikite
authors.affiliation: EHESP Rennes, Sorbonne Paris Cité , Rennes , France ; Inserm UMR 1085-IRSET , Rennes , France.
authors.forename: Séverine
authors.initials: S
authors.lastname: Deguen
authors.affiliation: Inserm UMR 1085-IRSET , Rennes , France.
authors.forename: Cindy
authors.initials: C
authors.lastname: Padilla
authors.affiliation: Service de néphrologie , CHU Rennes , Rennes , France.
authors.forename: Muriel
authors.initials: M
authors.lastname: Siebert
authors.affiliation: Agence de la biomédecine , Saint Denis La Plaine , France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Couchoud
authors.affiliation: Service de néphrologie , CHU Rennes , Rennes , France ; UMR 6290, équipe Kyca, Université de Rennes 1 , Rennes , France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Vigneau
authors.affiliation: EHESP Rennes, Sorbonne Paris Cité, EA MOS , Rennes , France.
authors.forename: Sahar
authors.initials: S
authors.lastname: Bayat
keywords: ESRD incidence; fine geographic scale; neighbourhood deprivation; spatial analysis