title: Medical practice patterns and socio-economic factors may explain geographical variation of end-stage renal disease incidence.
abstract: BACKGROUND
  Incidence rates of renal replacement therapy (RRT) for end-stage renal disease (ESRD) vary geographically not only between but within countries. This study uses data from the French REIN registry to quantify the extent to which socio-economic environment, health care supply and medical practice patterns such as early dialysis initiation or greater propensity to accept frail or elderly patients for dialysis, may explain spatial patterns of ESRD incidence in 85 French districts.
  
  
  METHODS
  The association between age- and sex-adjusted incidence rates of RRT in 2008-09 and 17 indicators was explored at the district level with geographically appropriate methods, before and after controlling for the effects of diabetes and the other significant indicators. Rate ratios (RR) and credible intervals (CI) were estimated for a 1-SD increase of each covariate.
  
  
  RESULTS
  Crude RRT incidence by district ranged from 85.8 to 225.5 per million inhabitants. The age- and sex-adjusted RRT incidence increased with the proportion of people unemployed (RR: 1.05, 95% CI 1.01-1.09), the population density (RR: 1.07, 95% CI 1.02-1.12) and the prevalence of diabetes (RR: 1.08, 95% CI 1.03-1.12). It also increased with the proportions of incident ESRD patients >85 years (RR: 1.02, 95% CI 0.99-1.06), of deaths within the first 3 months of RRT (RR: 1.03, 95% CI 1.0-1.06) and of nephrologists in private practice (RR: 1.05, 95% CI 1.01-1.08) and with the median estimated glomerular filtration rate (eGFR) at dialysis initiation (RR: 1.06, 95% CI 1.02-1.09).
  
  
  CONCLUSIONS
  This study confirms that socio-economic factors and diabetes explain substantial between-area variations in RRT incidence and highlights the variability of practice patterns, especially decisions about RRT and their potential impact on incidence.
authors: REIN Registry, Biomedicine Agency, La Plaine-Saint Denis, France. cecile.couchoud@biomedecine.fr
authors: Cécile
authors: C
authors: Couchoud
authors: Chantal
authors: C
authors: Guihenneuc
authors: Florian
authors: F
authors: Bayer
authors: Vincent
authors: V
authors: Lemaitre
authors: Philippe
authors: P
authors: Brunet
authors: Bénédicte
authors: B
authors: Stengel
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D005843:Geography; D006801:Humans; D007676:Kidney Failure, Chronic / Q000401:mortality* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians'; D011379:Prognosis; D012042:Registries; D017582:Renal Replacement Therapy / Q000706:statistics & numerical data* / Q000639:trends; D012959:Socioeconomic Factors; D015996:Survival Rate; D055815:Young Adult