title: Impact of social factors on patients on peritoneal dialysis.
abstract: BACKGROUND
  Clinical outcomes among patients on peritoneal dialysis (PD) might not be linked to medical factors alone. We studied the clinical impact of various social factors among patients on PD.
  
  
  METHODS
  In a cohort of 102 consecutive patients who started PD in a single centre between 2003 and 2004, we evaluated the effects of social factors on the development of peritonitis and risk of hospitalization after initiation of PD.
  
  
  RESULTS
  Of 102 incident PD patients, 35 subjects (34.3%) were referred to nephrologists more than 3 months before dialysis initiation. During 85.7 patient-years of observation (median follow-up, 10.7 months), four subjects died and six underwent kidney transplantation. Patients receiving social security assistance and those younger than 40 years fared worse than others in terms of their risk of peritonitis. Mean peritonitis-free time for subjects who were on social security assistance was 2.7 months, and for those who were not, 16.4 months (P = 0.045). In the Cox proportional hazards analysis, need for social security assistance and illiteracy were the only statistically significant factors associated with the time to a first peritonitis, after adjustment for social characteristics and relevant coexisting medical factors. Dependence on social security assistance prior to PD was associated with a >2-fold increased likelihood of peritonitis, with an adjusted risk ratio of 2.69 (95% confidence interval, 1.10 to 6.54; P = 0.029). The total number of hospitalization days was similar between those who received social security assistance and those who did not: 17.4+/-14.6 days (range, 4-50 days) vs 17.9+/-14.0 days (range, 0-60 days) (P = 0.89).
  
  
  CONCLUSIONS
  Our results confirm that socioeconomic status is closely associated with the rate of peritonitis among PD patients. The long-term reliability of these social predictors remains to be validated.
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China. Chow_Kai_Ming@alumni.cuhk.net
authors.forename: Kai Ming
authors.initials: KM
authors.lastname: Chow
authors.forename: Cheuk Chun
authors.initials: CC
authors.lastname: Szeto
authors.forename: Chi Bon
authors.initials: CB
authors.lastname: Leung
authors.forename: Man Ching
authors.initials: MC
authors.lastname: Law
authors.forename: Philip Kam-Tao
authors.initials: PK
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002681:China; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007676:Kidney Failure, Chronic / Q000523:psychology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000009:adverse effects / Q000523:psychology* / Q000706:statistics & numerical data; D010538:Peritonitis / Q000209:etiology; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D012943:Social Security / Q000191:economics; D012959:Socioeconomic Factors