title: Association of Multimorbidity with Mortality and Healthcare Utilization in Chronic Kidney Disease.
abstract: OBJECTIVE
  Chronic kidney disease (CKD) almost universally occurs in individuals with other medical problems. However, few studies have described CKD-related multimorbidity using a framework that identifies chronic conditions as concordant (having overlap in treatment goals) versus discordant (having opposing treatment recommendations) and unrelated (having no overlap, but contributing to complexity via different resource requirements).
  
  
  METHODS
  Retrospective cohort.
  
  
  METHODS
  Veterans Affairs (VA) Medical Centers.
  
  
  METHODS
  VA patients (n = 821,334) ages 18-100 years with at least one outpatient visit and incident CKD defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2for at least 3 months between January 1, 2005 and December 31, 2008 after excluding prevalent CKD.
  
  
  METHODS
  We determined the associations of number of chronic conditions (1, 2, 3, 4, 5, 6 or more) stratified by the presence of one or more discordant/unrelated conditions with mortality, hospitalizations and emergency department (ED) visits.
  
  
  RESULTS
  There were 381,187 deaths over 6.8 median years of follow-up. Higher risks of death, hospitalization and ED visits were associated with higher number of chronic conditions, among those with and without discordant/unrelated conditions. However, the magnitudes of the associations were consistently larger when at least one discordant/unrelated condition was present. For example, compared to patients with one concordant condition, patients with six or more concordant conditions had an age-, race- and sex-adjusted hazard ratio (HR) for mortality of 1.72 (95% CI 1.64-1.80) whereas those with six or more conditions, at least one of which was discordant/unrelated, had a HR of 2.05 (2.01-2.09) (P-interaction <0.001).
  
  
  CONCLUSIONS
  The presence of one or more discordant/unrelated conditions was associated with increased risk for adverse health outcomes, beyond the effect of multimorbidity.
authors.affiliation: Birmingham/Atlanta Geriatric Research, Education, and Clinical Center, Atlanta VA Medical Center, Decatur, Georgia.|Department of Medicine, Emory University, Atlanta, Georgia.
authors.forename: C Barrett
authors.initials: CB
authors.lastname: Bowling
authors.affiliation: Department of Medicine, Emory University, Atlanta, Georgia.
authors.forename: Laura
authors.initials: L
authors.lastname: Plantinga
authors.affiliation: Department of Medicine, Emory University, Atlanta, Georgia.|Atlanta VA Medical Center, Decatur, Georgia.
authors.forename: Lawrence S
authors.initials: LS
authors.lastname: Phillips
authors.affiliation: Department of Medicine, Emory University, Atlanta, Georgia.|Department of Epidemiology, Emory University, Atlanta, Georgia.
authors.forename: William
authors.initials: W
authors.lastname: McClellan
authors.affiliation: Birmingham/Atlanta Geriatric Research, Education, and Clinical Center, Atlanta VA Medical Center, Decatur, Georgia.|Department of Medicine, Emory University, Atlanta, Georgia.
authors.forename: Katharina
authors.initials: K
authors.lastname: Echt
authors.affiliation: Western Kentucky University, Bowling Green, Kentucky.
authors.forename: Neale
authors.initials: N
authors.lastname: Chumbler
authors.affiliation: Department of Epidemiology, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Gerald
authors.initials: G
authors.lastname: McGwin
authors.affiliation: Birmingham/Atlanta Geriatric Research, Education, and Clinical Center, Atlanta VA Medical Center, Decatur, Georgia.|Department of Medicine, Emory University, Atlanta, Georgia.
authors.forename: Ann
authors.initials: A
authors.lastname: Vandenberg
authors.affiliation: Geriatrics and Extended Care Services, Department of Veterans Affairs, Washington, District of Columbia.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Allman
authors.affiliation: Birmingham/Atlanta Geriatric Research, Education, and Clinical Center, Atlanta VA Medical Center, Decatur, Georgia.|Department of Medicine, Emory University, Atlanta, Georgia.
authors.forename: Theodore M
authors.initials: TM
authors.lastname: Johnson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D005260:Female; D005919:Glomerular Filtration Rate; D006760:Hospitalization / Q000706:statistics & numerical data; D006787:Hospitals, Veterans; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010342:Patient Acceptance of Health Care; D015995:Prevalence; D051436:Renal Insufficiency, Chronic / Q000401:mortality*; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
keywords: chronic kidney disease; comorbidity; multimorbidity