TABLE I.
Characteristics of Subjects Identified With Abnormal TCD in STOP 2 Compared With Subjects Identified in STOP or Through Routine Clinical Screen*
| Factor | STOP 2 (N = 88) | STOP and clinical screen (N=106a) | P-value |
|---|---|---|---|
| Age (years) | 7.6 (3.1) | 10.9 (3.8) | <0.0001 |
| Sex (n, % male) | 41 (46.6) | 50 (47.0) | 0.93 |
| Transfusion duration at the beginning of STOP2 (months) | 0.58 (1.5) | 36.5 (19.8) | <0.000l |
| Initial TCD velocity (cm/sec) | 227 (28) | 218 (17) | 0.012 |
| Baseline laboratory (before starting transfusion) | |||
| Hemoglobin (g/dl) | 7.4 (0.74) | 7.7 (1.15) | 0.317 |
| White blood cell count (109/L) | 14.1 (4.1) | 14.8 (5.4) | 0.557 |
| Platelet count (109/L) | 464 (104) | 404 (71) | 0.232 |
| Reticulocyte count (%) | 9.7 (2.6) | 8.2 (7.7) | 0.652 |
| Fetal hemoglobin (%) | 2.9 (1.9) | 3.8 (3.4) | 0.574 |
| LDH (U/L) | 442 (104) | 431 (850) | 0.953 |
| Laboratory on transfusions—pre-transfusion value | |||
| Hemoglobin (g/dl) | 9.1 (1.0) | 9.3 (1.1) | 0.222 |
| HbS (%) | 37 (20) | 33 (18.1) | 0.153 |
| Reticulocyte count (%) | 9.1 (3.0) | 9.1 (4.1) | 0.959 |