Results of the case-control study (n = 220: 37 cases and 183 controls)
| . | Values . | Univariate analyses . | Multivariate analysis . | |||
|---|---|---|---|---|---|---|
| Variable . | Cases . | Controls . | OR (95% CI) . | P . | OR (95% CI) . | P . |
| Age at diagnosis, y, mean ± SD (range) | 47.2 ± 19.8 (12-79) | 40.9 ± 19.8 (3-91) | — | — | — | — |
| Age at diagnosis >40 y, n (%) | 25 (67.6) | 85 (46.5) | 2.51 (1.17-5.40) | .0186 | — | — |
| Female sex, n (%) | 25 (67.6) | 127 (69.4) | 0.91 (0.43-1.92) | .8074 | — | — |
| Secondary ITP, n (%) | 13 (35.1) | 16 (8.7) | 6.01 (2.44-14.81) | <.001 | 4.84 (1.31-17.86) | .0179 |
| Autoimmunity (clinical or biological), n (%) | 22 (59.5) | 52 (28.4) | 3.36 (1.67-6.82) | .0008 | — | — |
| ANA positive, n (%)* | 13 (35.1) | 43 (25.2) | 1.5 (0.72-3.28) | .2692 | — | — |
| DAT positive, n (%)† | 12 (35.3) | 43 (25.2) | 2.39 (0.86-6.69) | .0954 | — | — |
| MGUS, n (%)‡ | 7 (18.9) | 5 (2.9) | 10.00 (2.55-39.24) | .0010 | 5.94 (1.085-32.48) | .0400 |
| Malignant hematological disorder, n (%) | 7 (18.9) | 0 (0) | — | — | — | — |
| Bleeding symptoms at ITP diagnosis, n (%) | 28 (75.7) | 96 (52.8) | 2.79 (1.25-6.24) | .0124 | 3.54 (1.12-11.23) | .0320 |
| Platelet count at ITP diagnosis, g/L, median ± IQR | 8.5 ± 13.0 [0-79] | 17.0 ± 25.0 [0-137] | — | — | — | — |
| Platelet count at ITP diagnosis ≤10 g/L, n (%) | 26 (70.3) | 72 (39.1) | 3.78 (1.73-8.23) | .0008 | — | — |
| Response to corticosteroids, n (%)§ | 24 (68.6) | 142 (91.6) | 0.34 (0.20-0.58) | <.0001 | 0.384 (0.205-0.720) | .0029 |
| Response to IVIG, n (%)|| | 24 (68.6) | 54 (83.1) | 0.54 (0.30-0.96) | .0362 | — | — |
| . | Values . | Univariate analyses . | Multivariate analysis . | |||
|---|---|---|---|---|---|---|
| Variable . | Cases . | Controls . | OR (95% CI) . | P . | OR (95% CI) . | P . |
| Age at diagnosis, y, mean ± SD (range) | 47.2 ± 19.8 (12-79) | 40.9 ± 19.8 (3-91) | — | — | — | — |
| Age at diagnosis >40 y, n (%) | 25 (67.6) | 85 (46.5) | 2.51 (1.17-5.40) | .0186 | — | — |
| Female sex, n (%) | 25 (67.6) | 127 (69.4) | 0.91 (0.43-1.92) | .8074 | — | — |
| Secondary ITP, n (%) | 13 (35.1) | 16 (8.7) | 6.01 (2.44-14.81) | <.001 | 4.84 (1.31-17.86) | .0179 |
| Autoimmunity (clinical or biological), n (%) | 22 (59.5) | 52 (28.4) | 3.36 (1.67-6.82) | .0008 | — | — |
| ANA positive, n (%)* | 13 (35.1) | 43 (25.2) | 1.5 (0.72-3.28) | .2692 | — | — |
| DAT positive, n (%)† | 12 (35.3) | 43 (25.2) | 2.39 (0.86-6.69) | .0954 | — | — |
| MGUS, n (%)‡ | 7 (18.9) | 5 (2.9) | 10.00 (2.55-39.24) | .0010 | 5.94 (1.085-32.48) | .0400 |
| Malignant hematological disorder, n (%) | 7 (18.9) | 0 (0) | — | — | — | — |
| Bleeding symptoms at ITP diagnosis, n (%) | 28 (75.7) | 96 (52.8) | 2.79 (1.25-6.24) | .0124 | 3.54 (1.12-11.23) | .0320 |
| Platelet count at ITP diagnosis, g/L, median ± IQR | 8.5 ± 13.0 [0-79] | 17.0 ± 25.0 [0-137] | — | — | — | — |
| Platelet count at ITP diagnosis ≤10 g/L, n (%) | 26 (70.3) | 72 (39.1) | 3.78 (1.73-8.23) | .0008 | — | — |
| Response to corticosteroids, n (%)§ | 24 (68.6) | 142 (91.6) | 0.34 (0.20-0.58) | <.0001 | 0.384 (0.205-0.720) | .0029 |
| Response to IVIG, n (%)|| | 24 (68.6) | 54 (83.1) | 0.54 (0.30-0.96) | .0362 | — | — |
ANA, antinuclear antibodies; DAT, direct antiglobulin test; IQR, interquartile range.
12 missing values among controls.
113 missing values among controls and 3 among cases.
10 missing values among controls.
28 missing values among controls and 2 among cases.
118 missing values among controls and 2 among cases.