Relapse incidence rates related to remission ADAMTS13 activity measurements within 1 year
| Patient-years with and without ADAMTS13 measurements . | Patient-years . | Relapses (patients), n . | Incidence of relapse per 100 patient-years (95% CI) . |
|---|---|---|---|
| All patient-years | 445.6 | 27 (18) | 6.06 (2.24-13.14) |
| Patient-years without ADAMTS13 measurement | 160.6 | 17 (13) | 10.59 (5.20-19.15) |
| Patient-years with ADAMTS13 measurement | 285.0 | 10 (9) | 3.51 (0.85-9.52) |
| Patient-years with and without ADAMTS13 measurements . | Patient-years . | Relapses (patients), n . | Incidence of relapse per 100 patient-years (95% CI) . |
|---|---|---|---|
| All patient-years | 445.6 | 27 (18) | 6.06 (2.24-13.14) |
| Patient-years without ADAMTS13 measurement | 160.6 | 17 (13) | 10.59 (5.20-19.15) |
| Patient-years with ADAMTS13 measurement | 285.0 | 10 (9) | 3.51 (0.85-9.52) |
Patient-years were calculated by assigning 12 months for each ADAMTS13 measurement during remission. For example, patient 11 (supplemental Table 1) contributed 6 patient-years. She contributed 1 patient-year to the ADAMTS13 <10% row, 5 patient-years to the ADAMTS13 activity ≥10% row, 3 patient-years to the ADAMTS13 <15% row, and 3 patient-years to the ADAMTS13 activity ≥15% row (see Table 2). She did not have measurements for 4 years; therefore, she also contributed 4 patient-years to the row “Patient-years without ADAMTS13 measurements.” Twenty-seven relapses occurred in the 57 cohort 1 patients (2004-2015). Ten relapses were preceded by an ADAMTS13 measurement within 12 months, and 17 were not.