Table 5.
Fine and Gray regression analysis to determine risk factors for developing myelofibrosis in patients with essential thrombocythemia (N=144).
| Univariate analysis | Multivariate analysis | ||||||
|---|---|---|---|---|---|---|---|
| HR | 95% CI | P | HR | 95% CI | P | ||
| Factors at diagnosis | |||||||
| Age >60 yr | 1.89 | 0.59–6.05 | 0.286 | - | - | - | |
| Male | 1.82 | 0.49–6.74 | 0.367 | - | - | - | |
| IPSET high | 0.83 | 0.24–2.83 | 0.768 | - | - | - | |
| WBC >11.0×109/L | 0.82 | 0.27–2.49 | 0.721 | - | - | - | |
| Monocyte >1.0×109/L | 2.79 | 1.23–9.12 | 0.045 | 3.57 | 1.17–10.91 | 0.026 | |
| Platelet >1,000×109/L | 0.92 | 0.30–2.85 | 0.890 | - | - | - | |
| LDH >1.5×UNL | 0.58 | 0.15–2.27 | 0.432 | - | - | - | |
| Positive JAK2V617F | 0.72 | 0.21–2.50 | 0.602 | - | - | - | |
| Positive CALR mutation | 3.26 | 1.01–10.47 | 0.048 | 4.42 | 1.20–16.37 | 0.026 | |
| Thrombosis before or at diagnosis | 1.86 | 0.52–6.66 | 0.342 | - | - | - | |
| Hydroxyurea treatment | 1.27 | 0.27–5.94 | 0.766 | - | - | - | |
Abbreviations: CI, confidence interval; HR, hazard ratio; IPSET, International prognostic scoring for essential thrombocythemia; LDH, lactate dehydrogenase; UNL, upper normal limit.