Table 1.
Baseline characteristics of the study population at the time of ESRD (HD initiation)
| Characteristic | Entire Study Population (n=115,425) | Access Type: Fistula (n=21,436) | Access Type: Graft (n=3472) | Access Type: Catheter (n=90,517) | P Value |
|---|---|---|---|---|---|
| Age at ESRD onset, yr | |||||
| Mean (SD) | 76.9 (6.4) | 76.2 (6.0) | 76.2 (6.0) | 77.2 (6.5) | <0.001 |
| Median (interquartile range) | 77 (10) | 76 (10) | 76 (10) | 77 (10) | |
| Age categories (yr), % | <0.001 | ||||
| 67–79 (n=74,997) | 65 | 69.7 | 69.5 | 63.7 | |
| 80–89 (n=37,149) | 32.2 | 28.9 | 29.1 | 33.1 | |
| >90 (n=3279) | 2.8 | 1.4 | 1.4 | 3.2 | |
| Race, % | <0.001 | ||||
| White | 75.5 | 77.8 | 62.2 | 75.5 | |
| Black | 20.3 | 18.1 | 33.2 | 20.3 | |
| Native American | 0.7 | 0.8 | 0.6 | 0.6 | |
| Asian | 3.5 | 3.3 | 3.9 | 3.5 | |
| Other | 0.1 | 0.04 | 0.1 | 0.1 | |
| Sex, % | <0.001 | ||||
| Woman | 47.1 | 41.6 | 57.3 | 48 | |
| Man | 52.9 | 58.4 | 42.7 | 52 | |
| BMI (kg/m2) | 27.3 (6.8) | 27.9 (6.5) | 28.0 (6.9) | 27.1 (6.8) | <0.001 |
| BMI categories (kg/m2) | |||||
| Underweight (<18.5) | 6.0 | 4.1 | 4.8 | 6.5 | <0.001 |
| Normal (18.5–24.9) | 36.0 | 32.4 | 33.2 | 37.0 | |
| Overweight (25–29.9) | 30.7 | 33.4 | 30.2 | 30.0 | |
| Obese (≥30) | 27.3 | 30.1 | 31.8 | 26.5 | |
| Comorbidity index | 8.3 (1.6) | 8.1 (1.5) | 8.2 (1.5) | 8.3 (1.6) | <0.001 |
| Diabetes, % | <0.001 | ||||
| Yes | 55.1 | 56.2 | 59.9 | 54.6 | |
| No | 44.9 | 43.8 | 40.1 | 45.4 | |
| Malignancy, % | <0.001 | ||||
| Yes | 11.4 | 10.4 | 10 | 11.7 | |
| No | 88.6 | 89.6 | 90 | 88.3 | |
| PVD, % | <0.001 | ||||
| Yes | 18.3 | 18.2 | 17.6 | 18.3 | |
| No | 81.7 | 81.8 | 82.4 | 81.7 | |
| Duration of pre-ESRD nephrology care, % | <0.001 | ||||
| No care | 31.1 | 5.6 | 6.7 | 38.1 | |
| 0–6 months | 10.7 | 13.7 | 13 | 9.9 | |
| 6–12 months | 22.1 | 29.1 | 31.1 | 20.1 | |
| >12 months | 22.7 | 45.7 | 42.8 | 16.5 | |
| Missing | 13.3 | 5.8 | 6.4 | 15.4 | |
| Primary cause of ESRD, % | <0.001 | ||||
| Diabetes | 40.7 | 44.8 | 48.4 | 39.4 | |
| GN | 4.1 | 5.7 | 4.5 | 3.8 | |
| Hypertension | 36.4 | 37.3 | 37 | 36.1 | |
| Cystic disease | 0.9 | 2.1 | 1.4 | 0.6 | |
| Other | 18 | 10.1 | 8.6 | 20.2 |
Continuous variables are presented as mean (SD), and categorical variables are presented as the percent of total. P values are based on ANOVA test. Nonsignificant P value supports the null hypothesis stating that all group means are equal to each other.