Updated comorbidity assessments and outcomes in prevalent hemodialysis patients.
When evaluating clinical characteristics and outcomes in patients on hemodialysis, the prevalence and severity of comorbidity may change over time. Knowing whether updated assessments of comorbidity enhance predictive power will assist the design of future studies. We conducted a secondary data analysis of 1846 prevalent hemodialysis patients from 15 US clinical centers enrolled in the HEMO study. Our primary explanatory variable was the Index of Coexistent Diseases score, which aggregates comorbidities, as a time-constant and time-varying covariate. Our outcomes of interest were all-cause mortality, time to first hospitalization, and total hospitalizations. We used Cox proportional hazards regression. Accounting for an updated comorbidity assessment over time yielded a more robust association with mortality than accounting for baseline comorbidity alone. The variation explained by time-varying comorbidity assessments on time to death was greater than age, baseline serum albumin, diabetes, or any other covariates. There was a less pronounced advantage of updated comorbidity assessments on determining time to hospitalization. Updated assessments of comorbidity significantly strengthen the ability to predict death in patients on hemodialysis. Future studies in dialysis should invest the necessary resources to include repeated assessments of comorbidity.
Chang
Tara I
TI
Division of Nephrology, Stanford University School of Medicine, Palo Alto, California, USA. tichang@stanford.edu
Paik
Jane
J
Greene
Tom
T
Miskulin
Dana C
DC
Chertow
Glenn M
GM
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D015897:Comorbidity; D003928:Diabetic Nephropathies / Q000453:epidemiology / Q000401:mortality / Q000628:therapy; D005260:Female; D006760:Hospitalization; D006801:Humans; D007676:Kidney Failure, Chronic / Q000453:epidemiology / Q000401:mortality / Q000628:therapy; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D006435:Renal Dialysis / Q000009:adverse effects / Q000401:mortality; D012709:Serum Albumin / Q000378:metabolism; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
D012709:Serum Albumin