Table 1.

Characteristics of dialysis patients in the discovery cohort and replication cohort

Patient CharacteristicsDiscovery Cohort n=141Replication Cohort n=180
Demographic and Clinical Characteristics
 Age, yr56.6±14.650.6±13.8
 Male, %64.561.7
 White versus nonwhite, %42.626.1
 Months receiving dialysisa25 (12, 60)42 (20, 80)
Education, %
 < High school12.816.7
 High school graduate27.024.4
 Post–high school60.258.9
English- versus Spanish-speaking, %95.080.6
Diabetes, %46.141.7
Stroke, %12.18.9
Peritoneal dialysis, %7.10
Systolic BP, mmHg141.3±26.1147.1±18.2
Diastolic BP, mmHg77.0±14.980.1±12.0
Hemoglobin, g/dl11.9±1.012.1±1.2
Urea reduction ratio, %67.8±8.673.0±5.7
BUN, mg/dl67.2±19.058.0±17.6
Cognitive Function
 Trail Making Test Part B130.8±69.8162.4±97.2
 Digit Symbol Substitution test49.9±17.549.1±19.0b
 Impaired executive function, %57.564.4
  • Higher scores on the Trail Making Test Part B indicate poorer cognitive function. Lower scores on the Digit Symbol Substitution test indicate poorer cognitive function.

  • a Median (25th, 75th percentile).

  • b (n=59).