Epileptic seizures in patients following allogeneic hematopoietic stem cell transplantation: a retrospective analysis of incidence, risk factors, and survival rates.

The incidence of epileptic seizures among allogeneic hematopoietic stem cell transplant (allo-HSCT) patients has been poorly described. No report has systematically studied epilepsy's possible causes, risk factors, and effect on prognosis among allo-HSCT patients. We retrospectively examined data from 1461 patients who underwent allo-HSCT within the past 6.5 yr at the Institute of Hematology and People's Hospital, Peking University. The cumulative incidence of all epileptic seizure complications was 7.1%. Of the 79 transplant patients who had epileptic seizures, 3 (3.8%) experienced a seizure during the conditioning stage, 52 (65.8%) between day 0 and day 100, 20 (25.3%) from day 100 to the first year, and 4 (5.1%) after the first year. Multivariate regression analysis identified the age of the recipient as (≤ 18 yr) (p < 0.001), donor type (p = 0.004), graft versus host disease (aGVHD) (p = 0.018), and hyponatremia (p = 0.003) as independent risk factors for epileptic seizures among allo-HSCT patients. The median survival time of patients with epileptic seizures was 246 d after transplantation (ranging between 18 and 2170 d). Survival after one yr and 6.5 yr was significantly reduced in patients who developed epileptic seizure complications compared with those who did not (57.2% vs. 75.7% at one yr, p = 0.015, and 31.1% vs. 71.4% at five yr, p < 0.001). Of the 79 patients who experienced epileptic seizure complications, 53.2% died (n = 42). The survival rate of these patients was relatively low, and cerebrovascular disorders or central nervous system infection-related epileptic seizures usually resulted in a high mortality and poor prognosis. A patient transplantation age which is younger than 18 yr, related mismatched transplants, aGVHD, and hyponatremia are risk factors for epileptic seizures in allo-HSCT recipients. Epileptic seizures among allo-HSCT patients are associated with a poor prognosis.