Results of Cox Proportional Hazards Regression, Adjusted for Potential Confounders
| Variable . | Relative Risk* . | 95% CI . | P Value . |
|---|---|---|---|
| All patients (N = 356) | |||
| Splenectomy | 2.61 | 1.38-4.95 | .003 |
| Platelet count (<100 × 109/L) | 2.45 | 1.26-4.75 | .007 |
| Blast cells at diagnosis (>0) | 2.31 | 1.30-4.08 | .004 |
| Hemoglobin (<9 g/dL) | 1.66 | 0.92-2.98 | .09 |
| Hydroxyurea (dose >300 g) | 1.02 | 0.38-2.67 | .96 |
| Patients splenectomized (N = 85) | |||
| For symptomatic splenomegaly v for transfusion-dependent anemia | 1.59 | 0.61-4.11 | .33 |
| Receiving hydroxyurea v not receiving hydroxyurea | 1.23 | 0.52-2.91 | .62 |
| Variable . | Relative Risk* . | 95% CI . | P Value . |
|---|---|---|---|
| All patients (N = 356) | |||
| Splenectomy | 2.61 | 1.38-4.95 | .003 |
| Platelet count (<100 × 109/L) | 2.45 | 1.26-4.75 | .007 |
| Blast cells at diagnosis (>0) | 2.31 | 1.30-4.08 | .004 |
| Hemoglobin (<9 g/dL) | 1.66 | 0.92-2.98 | .09 |
| Hydroxyurea (dose >300 g) | 1.02 | 0.38-2.67 | .96 |
| Patients splenectomized (N = 85) | |||
| For symptomatic splenomegaly v for transfusion-dependent anemia | 1.59 | 0.61-4.11 | .33 |
| Receiving hydroxyurea v not receiving hydroxyurea | 1.23 | 0.52-2.91 | .62 |
*Data from a Cox proportional-hazards regression model giving the risk ratio and 95% CIs for blast transformation are shown. Risk ratios greater than 1.0 imply a higher risk of blast transformation. For all dichotomous variables, the patients with the characteristic were compared with those without it.