title: Associations of employment status and educational levels with mortality and hospitalization in the dialysis outcomes and practice patterns study in Japan.
abstract: BACKGROUND
  Socioeconomic status (SES) factors such as employment, educational attainment, income, and marital status can affect the health and well-being of the general population and have been associated with the prevalence of chronic kidney disease (CKD). However, no studies to date in Japan have reported on the prognosis of patients with CKD with respect to SES. This study aimed to investigate the influences of employment and education level on mortality and hospitalization among maintenance hemodialysis (HD) patients in Japan.
  
  
  METHODS
  Data on 7974 HD patients enrolled in Dialysis Outcomes and Practice Patterns Study phases 1-4 (1999-2011) in Japan were analysed. Employment status, education level, demographic data, and comorbidities were abstracted at entry into DOPPS from patient records. Mortality and hospitalization events were collected during follow-up. Patients on dialysis < 120 days at study entry were excluded from the analyses. Cox regression modelled the association between employment and both mortality and hospitalization among patients < 60 years old. The association between education and outcomes was also assessed. The association between patient characteristics and employment among patients < 60 years old was assessed using logistic regression.
  
  
  RESULTS
  During a median follow-up of 24.9 months (interquartile range, 18.4-32.0), 10% of patients died and 43% of patients had an inpatient hospitalization. Unemployment was associated with mortality (hazard ratio [HR] = 1.57; 95% confidence interval [CI]: 1.05-2.36) and hospitalization (HR = 1.25; 95% CI: 1.08-1.44). Compared to patients who graduated from university, patients with less than a high school (HS) education and patients who graduated HS with some college tended to have elevated mortality (HR = 1.41; 95% CI, 1.04-1.92 and HR = 1.36; 95% CI: 1.02-1.82, respectively) but were not at risk for increased hospitalizations. Factors associated with unemployment included lower level of education, older age, female gender, longer vintage, and several comorbidities.
  
  
  CONCLUSIONS
  Employment and education status were inversely associated with mortality in patients on maintenance HD in Japan. Employment but not education was also inversely associated with hospitalizations. After adjustment for comorbidities, the associations with clinical outcomes tended to be stronger for employment than education status.
authors.affiliation: Department of Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yasuo
authors.identifier: http://orcid.org/0000-0002-9077-2631
authors.initials: Y
authors.lastname: Imanishi
authors.affiliation: Department of Healthcare Epidemiology, School of Public Health in the Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Fukuma
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI, United States of America.
authors.forename: Angelo
authors.initials: A
authors.lastname: Karaboyas
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI, United States of America.|University of Michigan, Ann Arbor, MI, United States of America.
authors.forename: Bruce M
authors.initials: BM
authors.lastname: Robinson
authors.affiliation: Arbor Research Collaborative for Health, Ann Arbor, MI, United States of America.
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Pisoni
authors.affiliation: Medical Affairs, Kyowa Hakko Kirin, Co. Ltd., Tokyo, Japan.
authors.forename: Takanobu
authors.initials: T
authors.lastname: Nomura
authors.affiliation: Department of Blood Purification and Internal Medicine, Kidney Center, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Akiba
authors.affiliation: Division of Nephrology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan.
authors.forename: Tadao
authors.initials: T
authors.lastname: Akizawa
authors.affiliation: National Graduate Institute for Policy Studies, Tokyo, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kurokawa
authors.affiliation: Division of Nephrology and Dialysis Center, Shonantobu General Hospital, Kanagawa, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Saito
authors.affiliation: Department of Healthcare Epidemiology, School of Public Health in the Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Center for Innovative Research for Communities and Clinical Excellence, Fukushima Medical University, Fukushima, Japan.
authors.forename: Shunichi
authors.initials: S
authors.lastname: Fukuhara
authors.affiliation: Department of Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Inaba
mesh_terms: D000368:Aged; D015331:Cohort Studies; D015897:Comorbidity; D004651:Employment; D005260:Female; D006760:Hospitalization; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007676:Kidney Failure, Chronic / Q000453:epidemiology / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians'; D016016:Proportional Hazards Models; D006435:Renal Dialysis / Q000401:mortality*; D012959:Socioeconomic Factors