Description of patient characteristics at the time of initial presentation: comparison between primary ITP and secondary ITP, primary ITP and infection-associated secondary ITP, and primary ITP and noninfectious secondary ITP plus non-IT
| Characteristic . | Primary ITP (1) . | All secondary ITP and non-IT (2) . | Subgroup: infection-associated secondary ITP (3) . | Subgroup: noninfectious causes* (4) . | P (1) vs (2) . | P (1) vs (3) . | P (1) vs (4) . |
|---|---|---|---|---|---|---|---|
| Total patients (%) | 4093 (100) | 113 (100) | 53 (100) | 60 (100) | |||
| Female (% of total) | 1930 (47) | 63 (56) | 26 (49) | 38 (63) | .058 | NS | .018 |
| Age, median (IQR), y | 4 (1.9; 7.75) | 6.4 (2.8; 12.4) | 3.2 (1.2; 6.7) | 11.3 (5.1; 13.7) | <.001 | NS | <.001 |
| Family history of thrombocytopenia (%) | 87 (2.2) | 4 (3.5) | 0 (0) | 4 (6.7) | NS | NS | .05 |
| Comorbidities (%) | 441 (11) | 26 (23) | 8 (15) | 19 (32) | <.001 | NS | <.001 |
| Platelet count, median (IQR), ×109/L | 12 (5; 25) | 14 (7;29) | 12 (6; 28) | 14 (8; 30) | NS | NS | NS |
| No. of patients with platelet count <20 × 109/L (%) | 2732 (67) | 69 (61) | 35 (66) | 34 (57) | NS | NS | NS |
| No bleeding (%) | 209 (5.1) | 20 (18) | 6 (11) | 14 (23) | <.001 | NS | <.001 |
| Platelet-enhancing treatment (%) | 2640 (69) | 73 (65) | 37 (70) | 35 (58) | NS | NS | NS |
| Characteristic . | Primary ITP (1) . | All secondary ITP and non-IT (2) . | Subgroup: infection-associated secondary ITP (3) . | Subgroup: noninfectious causes* (4) . | P (1) vs (2) . | P (1) vs (3) . | P (1) vs (4) . |
|---|---|---|---|---|---|---|---|
| Total patients (%) | 4093 (100) | 113 (100) | 53 (100) | 60 (100) | |||
| Female (% of total) | 1930 (47) | 63 (56) | 26 (49) | 38 (63) | .058 | NS | .018 |
| Age, median (IQR), y | 4 (1.9; 7.75) | 6.4 (2.8; 12.4) | 3.2 (1.2; 6.7) | 11.3 (5.1; 13.7) | <.001 | NS | <.001 |
| Family history of thrombocytopenia (%) | 87 (2.2) | 4 (3.5) | 0 (0) | 4 (6.7) | NS | NS | .05 |
| Comorbidities (%) | 441 (11) | 26 (23) | 8 (15) | 19 (32) | <.001 | NS | <.001 |
| Platelet count, median (IQR), ×109/L | 12 (5; 25) | 14 (7;29) | 12 (6; 28) | 14 (8; 30) | NS | NS | NS |
| No. of patients with platelet count <20 × 109/L (%) | 2732 (67) | 69 (61) | 35 (66) | 34 (57) | NS | NS | NS |
| No bleeding (%) | 209 (5.1) | 20 (18) | 6 (11) | 14 (23) | <.001 | NS | <.001 |
| Platelet-enhancing treatment (%) | 2640 (69) | 73 (65) | 37 (70) | 35 (58) | NS | NS | NS |
% refers to the total number of patients in the subgroups.
NS, not significant.
Regroups patients with secondary autoimmune-associated ITP, secondary immunodeficiency-associated ITP, drug-induced secondary ITP, aplastic anemia, and malignancy.