Univariate Cox regression analysis for HbSS/HbSβ0 thalassemia
| HbSS/HbSβ0 thalassemia . | Hazard ratio (95% CI) . | P value . |
|---|---|---|
| Demographics | ||
| α-Thalassemia* | 1.34 (0.67-2.71) | .411 |
| Sex† | 0.67 (0.34-1.34) | .261 |
| Admissions | ||
| High admission rate, >0.5/y‡ | 3.13 (1.57-6.26) | .001 |
| Hydroxyurea use | 1.48 (0.57-3.86) | .42 |
| Transfusions | 1.00 (0.35-2.87) | .99 |
| Steady-state O2saturations | ||
| Oxygen saturations <95%§ | 2.84 (1.36-5.92) | .005 |
| Hematology | ||
| White blood cell count, ×109/L | 1.18 (1.04-1.35) | .01 |
| Hemoglobin, g/L | 0.98 (0.96-1.00) | .07 |
| Platelets, ×109/L | 1.00 (0.99-1.00) | .16 |
| Reticulocytes, ×109/L | 1.00 (1.00-1.00) | .29 |
| Fetal hemoglobin high/low|| | 0.44 (0.20-0.96) | .04 |
| Biochemistry | ||
| Lactate dehydrogenase, IU/L | 1.00 (1.00-1.00) | .04 |
| Ln C-reactive protein, mg/L | 1.98 (1.16-3.38) | .013 |
| Ferritin >1000 μg/L¶ | 2.52 (1.21-5.23) | .013 |
| Liver enzymes | ||
| Ln total bilirubin, µmol/L | 1.78 (1.02-3.10) | .04 |
| Ln aspartate transaminase, IU/L | 3.84 (2.11-7.00) | <.001 |
| Ln alanine transaminase, IU/L | 2.37 (0.91-6.22) | .08 |
| Ln γ-glutamyl transferase, IU/L | 1.44 (0.97-2.14) | .07 |
| Ln alkaline phosphatase, IU/L | 3.24 (1.93-5.45) | <.0001 |
| Renal function | ||
| Ln creatinine, µmol/L | 2.11 (1.31-3.40) | .002 |
| Ln urinary albumin creatinine ratio, mg/mmol | 1.34 (1.07-1.68) | .01 |
| HbSS/HbSβ0 thalassemia . | Hazard ratio (95% CI) . | P value . |
|---|---|---|
| Demographics | ||
| α-Thalassemia* | 1.34 (0.67-2.71) | .411 |
| Sex† | 0.67 (0.34-1.34) | .261 |
| Admissions | ||
| High admission rate, >0.5/y‡ | 3.13 (1.57-6.26) | .001 |
| Hydroxyurea use | 1.48 (0.57-3.86) | .42 |
| Transfusions | 1.00 (0.35-2.87) | .99 |
| Steady-state O2saturations | ||
| Oxygen saturations <95%§ | 2.84 (1.36-5.92) | .005 |
| Hematology | ||
| White blood cell count, ×109/L | 1.18 (1.04-1.35) | .01 |
| Hemoglobin, g/L | 0.98 (0.96-1.00) | .07 |
| Platelets, ×109/L | 1.00 (0.99-1.00) | .16 |
| Reticulocytes, ×109/L | 1.00 (1.00-1.00) | .29 |
| Fetal hemoglobin high/low|| | 0.44 (0.20-0.96) | .04 |
| Biochemistry | ||
| Lactate dehydrogenase, IU/L | 1.00 (1.00-1.00) | .04 |
| Ln C-reactive protein, mg/L | 1.98 (1.16-3.38) | .013 |
| Ferritin >1000 μg/L¶ | 2.52 (1.21-5.23) | .013 |
| Liver enzymes | ||
| Ln total bilirubin, µmol/L | 1.78 (1.02-3.10) | .04 |
| Ln aspartate transaminase, IU/L | 3.84 (2.11-7.00) | <.001 |
| Ln alanine transaminase, IU/L | 2.37 (0.91-6.22) | .08 |
| Ln γ-glutamyl transferase, IU/L | 1.44 (0.97-2.14) | .07 |
| Ln alkaline phosphatase, IU/L | 3.24 (1.93-5.45) | <.0001 |
| Renal function | ||
| Ln creatinine, µmol/L | 2.11 (1.31-3.40) | .002 |
| Ln urinary albumin creatinine ratio, mg/mmol | 1.34 (1.07-1.68) | .01 |
Significant hazards (risk factors) are italicized. Nonnormal continuous variables were natural logged for statistical comparison (marked “Ln”). Dichotomous variables were handled as follows:
α-Thalassemia, default = no.
Sex, default = male.
Mean hospitalization rate, default ≤0.5 admissions per year.
Oxygen saturations, default = normal (≥95%).
HbF based on median split of validated HbF values, default HbF <5.5%.
Iron overload based on ferritin >1000 μg/L, default = no.