Abstract
Patients who survive an acute episode of TTP are expected to have complete recovery. The only currently appreciated risk is the possibility of a recurrent acute episode. However, survivors often describe problems that interfere with daily activities such as decreased energy and poor concentration and memory in spite of normal physical examination and laboratory data. The Oklahoma TTP-HUS Registry has complete follow up data on 333 of 335 consecutive patients with clinically diagnosed TTP or HUS in central-western Oklahoma from January 1, 1989 through December 2005. Since February 1998 we have collected QOL data annually, beginning one year after the initial episode, using the Medical Outcomes Study Short Form-36 (SF-36) to assess eight domains of physical and mental health. We compared our patients to US population norms that have been determined from the total, non-institutionalized US population. Results are reported as the percent of our patients who were within the top 75 percent of the US population values. The parameter of the top 75 percent of the US population was selected to approximate a range of normal function.
Percent of TTP patients in the top 75% of the US Population for all SF-36 domains
| Data for all TTP patients who had their first QOL less than two years from the time of their initial episode and who did not relapse in that interval | ||
| SF-36 Domain | TTP Patients (n=76) | P |
| Vitality | 43% | <0.01 |
| Role physical | 46% | <0.01 |
| Physical functioning | 44% | <0.01 |
| Bodily pain | 63% | 0.17 |
| General health | 33% | <0.01 |
| Social functioning | 55% | <0.01 |
| Role Emotional | 62% | 0.01 |
| Mental health | 61% | 0.05 |
| Data for all TTP patients who had their first QOL less than two years from the time of their initial episode and who did not relapse in that interval | ||
| SF-36 Domain | TTP Patients (n=76) | P |
| Vitality | 43% | <0.01 |
| Role physical | 46% | <0.01 |
| Physical functioning | 44% | <0.01 |
| Bodily pain | 63% | 0.17 |
| General health | 33% | <0.01 |
| Social functioning | 55% | <0.01 |
| Role Emotional | 62% | 0.01 |
| Mental health | 61% | 0.05 |
Percent of TTP patients, by clinical category, in the top 75% of the US population for the SF-36 general health domain1
| 1Data for the general health domain, to compare patients designated in different clinical categories of TTP (n=122) 2Patients with ADAMTS13 deficiency are reported separately, not with their clinical category: 16 were idiopathic, 2 were pregnant, 1 had bloody diarrhea | |||
| Clinical Category | N | TTP Patients (n=122) | P |
| Idiopathic | 57 | 40% | <0.01 |
| Quinine-induced | 15 | 33% | <0.01 |
| Preganancy-associated | 18 | 44% | <0.01 |
| Bloody diarrhea prodrome | 13 | 38% | <0.01 |
| ADAMTS13 <10%2 | 19 | 32% | <0.01 |
| 1Data for the general health domain, to compare patients designated in different clinical categories of TTP (n=122) 2Patients with ADAMTS13 deficiency are reported separately, not with their clinical category: 16 were idiopathic, 2 were pregnant, 1 had bloody diarrhea | |||
| Clinical Category | N | TTP Patients (n=122) | P |
| Idiopathic | 57 | 40% | <0.01 |
| Quinine-induced | 15 | 33% | <0.01 |
| Preganancy-associated | 18 | 44% | <0.01 |
| Bloody diarrhea prodrome | 13 | 38% | <0.01 |
| ADAMTS13 <10%2 | 19 | 32% | <0.01 |
Patients who have recovered from TTP performed significantly worse than the US population for all domains of the SF-36 except for bodily pain. For the general health domain, patients in all categories were significantly worse than the US population. Thirty-two patients had ≥ 4 QOLs: there was a significant trend for improvement across time in the role physical domain (p<.01); the other 7 domains had no significant trend across time.
CONCLUSIONS: Following an acute episode of TTP, the QOL of patients is worse than the US population, suggesting that the ischemia of TTP may cause persistent physical and cognitive abnormalities.
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