Table 3.
Univariate Cox regression analysis for thromboembolic events with onset before week 12
| Category | Number | No. of events (%) |
Hazard ratio (95% CI)a |
P valueb |
|---|---|---|---|---|
| Age (years) | ||||
| < 65 | 206 | 7 (3.4) | Ref | 0.071 |
| ≥ 65 | 238 | 17 (7.1) | 2.21 (0.92–5.32) | |
| Previous ESA treatment | ||||
| Naive | 88 | 8 (9.1) | 2.11 (0.90–4.93) | 0.078 |
| Conversion | 356 | 16 (4.5) | Ref | |
| Previous ESA treatment, monthly dose (µg)c | ||||
| < 40 | 137 | 10 (7.3) | Ref | 0.276 |
| 40 to < 160 | 254 | 10 (3.9) | 0.52 (0.22–1.24) | |
| ≥ 160 | 53 | 4 (7.5) | 0.98 (0.31–3.13) | |
| Type of dialysis | ||||
| Hemodialysis | 388 | 24 (6.2) | Inf | 0.059 |
| Peritoneal dialysis | 56 | 0 (0.0) | Ref | |
| Dialysis vintage (months) | ||||
| ≤ 4 | 83 | 9 (10.8) | 2.74 (1.20–6.26) | 0.013 |
| > 4 | 361 | 15 (4.2) | Ref | |
| History of thromboembolism | ||||
| No | 329 | 16 (4.9) | Ref | 0.387 |
| Yes | 115 | 8 (7.0) | 1.45 (0.62–3.39) | |
| History of cardiovascular event | ||||
| No | 382 | 21 (5.5) | Ref | 0.822 |
| Yes | 62 | 3 (4.8) | 0.87 (0.26–2.92) | |
| Concomitant use of IV iron therapy | ||||
| No | 334 | 24 (7.2) | Inf | 0.003 |
| Yes | 110 | 0 (0.0) | Ref | |
| Concomitant use of oral iron therapy (including ferric citrate) | ||||
| No | 271 | 21 (7.7) | 4.61 (1.38–15.46) | 0.006 |
| Yes | 173 | 3 (1.7) | Ref | |
| Concomitant use of IV or oral iron therapy (including ferric citrate) | ||||
| No | 179 | 21 (11.7) | 11.25 (3.36–37.71) | < 0.001 |
| Yes | 265 | 3 (1.1) | Ref | |
CI confidence interval, ESA erythropoiesis-stimulating agent, Inf infinite, IV intravenous, Ref reference
aEstimated using Cox proportional hazards model
bP values based on log-rank test to test the null hypothesis of no difference in incidence across subgroup categories
cESA monthly dose was calculated by converting to darbepoetin alfa unit