Baseline characteristics of the study population (n=164)
| Variables . | n (% miss.) . | Overall . |
|---|---|---|
| Demographic characteristics | ||
| Age at entry, years (IQR) | 164 (0%) | 41 (31-58) |
| Female Gender, n (%) | 164 (0%) | 137 (84%) |
| Clinical history, n (%) | ||
| Prior thrombosis | 164 (0%) | 98 (60%) |
| Arterial | 164 (0%) | 26 (16%) |
| Venous | 164 (0%) | 78 (48%) |
| Both | 164 (0%) | 6 (4%) |
| Prior pregnancy complications* | 102 (0%) | 50 (49%) |
| Established APS | 164 (0%) | 118 (72%) |
| Comorbidities at baseline, n (%) | ||
| Autoimmune rheumatic diseases† | 164 (0%) | 45 (27%) |
| SLE | 164 (0%) | 26 (16%) |
| LLD | 164 (0%) | 18 (11%) |
| Active smoker at baseline | 163 (1%) | 55 (34%) |
| Hypertension | 163 (1%) | 48 (29%) |
| Diabetes | 164 (0%) | 13 (8%) |
| Anticoagulation at baseline, n (%) | ||
| VKA | 164 (0%) | 49 (30%) |
| LMWH | 163 (1%) | 23 (14%) |
| LDA | 163 (1%) | 50 (31%) |
| None | 163 (1%) | 67 (41%) |
| Disease-related autoantibodies, n (%) | ||
| LA+ only | 164 (0%) | 39 (24%) |
| IgM aCL–positive‡ | 164 (0%) | 24 (15%) |
| IgG aCL–positive‡ | 164 (0%) | 53 (32%) |
| aCL+ (IgM and/or IgG)‡ | 164 (0%) | 67 (41%) |
| IgM aβ2GPI–positive‡ | 145 (12%) | 63 (43%) |
| IgG aβ2GPI–positive‡ | 162 (1%) | 87 (54%) |
| aβ2GPI+ (IgM and/or IgG)‡ | 153 (7%) | 113 (74%) |
| “Triple positive”§ | 152 (7%) | 64 (42%) |
| Antiprothrombin IgM–positiveǁ | 119 (27%) | 26 (22%) |
| Antiprothrombin IgG–positive-positiveǁ | 119 (27%) | 30 (25%) |
| Antiprothrombin+ (IgM and/or IgG)ǁ | 119 (27%) | 49 (41%) |
| Variables . | n (% miss.) . | Overall . |
|---|---|---|
| Demographic characteristics | ||
| Age at entry, years (IQR) | 164 (0%) | 41 (31-58) |
| Female Gender, n (%) | 164 (0%) | 137 (84%) |
| Clinical history, n (%) | ||
| Prior thrombosis | 164 (0%) | 98 (60%) |
| Arterial | 164 (0%) | 26 (16%) |
| Venous | 164 (0%) | 78 (48%) |
| Both | 164 (0%) | 6 (4%) |
| Prior pregnancy complications* | 102 (0%) | 50 (49%) |
| Established APS | 164 (0%) | 118 (72%) |
| Comorbidities at baseline, n (%) | ||
| Autoimmune rheumatic diseases† | 164 (0%) | 45 (27%) |
| SLE | 164 (0%) | 26 (16%) |
| LLD | 164 (0%) | 18 (11%) |
| Active smoker at baseline | 163 (1%) | 55 (34%) |
| Hypertension | 163 (1%) | 48 (29%) |
| Diabetes | 164 (0%) | 13 (8%) |
| Anticoagulation at baseline, n (%) | ||
| VKA | 164 (0%) | 49 (30%) |
| LMWH | 163 (1%) | 23 (14%) |
| LDA | 163 (1%) | 50 (31%) |
| None | 163 (1%) | 67 (41%) |
| Disease-related autoantibodies, n (%) | ||
| LA+ only | 164 (0%) | 39 (24%) |
| IgM aCL–positive‡ | 164 (0%) | 24 (15%) |
| IgG aCL–positive‡ | 164 (0%) | 53 (32%) |
| aCL+ (IgM and/or IgG)‡ | 164 (0%) | 67 (41%) |
| IgM aβ2GPI–positive‡ | 145 (12%) | 63 (43%) |
| IgG aβ2GPI–positive‡ | 162 (1%) | 87 (54%) |
| aβ2GPI+ (IgM and/or IgG)‡ | 153 (7%) | 113 (74%) |
| “Triple positive”§ | 152 (7%) | 64 (42%) |
| Antiprothrombin IgM–positiveǁ | 119 (27%) | 26 (22%) |
| Antiprothrombin IgG–positive-positiveǁ | 119 (27%) | 30 (25%) |
| Antiprothrombin+ (IgM and/or IgG)ǁ | 119 (27%) | 49 (41%) |
n (% miss.)” reports the number of patients with fully observed data (% missing). IQR, interquartile range (median [25th-75th] percentile); LDA, low-dose aspirin.
Pregnancy complications were defined according to Sapporo criteria in the subgroup of 117 females who had at least 1 documented pregnancy.
Autoimmune rheumatic diseases were defined as a composite of systemic lupus erythematosus and lupus-like disease according to a local panel of rheumatology experts.
Cutoffs were defined as follows according to ISTH/Sapporo criteria cutoffs: aCL >40GPL/MPL U/mL, >8 GPL/MPL U/mL.
Triple-positivity was defined as being positive for LA and at least one class of immunoglobulins (IgM or IgG) for aCL and aβ2GPI.
Cutoffs were defined by the 90th percentile in 33 healthy volunteers without history of thrombosis, antiprothrombin IgM ≥11.54 U/mL, antiprothrombin IgG ≥8.68 U/mL.