Incidence and Risk Factors for Early-Onset Hypertension after Allogeneic Hematopoietic Stem Cell Transplantation in Children

BACKGROUND AND OBJECTIVES Survivors of pediatric hematopoietic stem cell transplantation (HSCT) are at risk for developing hypertension. The objectives of this study are to evaluate the prevalence and risk factors of early onset hypertension during the engraftment period after HSCT. SUBJECTS AND METHODS This is a retrospective study of 157 consecutive patients (mean age at HSCT: 9.1±5.1 years) who underwent HSCT for acute myeloid leukemia (n=47), acute lymphoblastic leukemia (n=43), severe aplastic anemia (n=41), and other reasons (n=26). Blood pressure data were collected at five time points: 0, 7, 14, 21, and 28 days after HSCT. Hypertension was defined as having systolic and/or diastolic blood pressure ≥95th percentile according to age, gender, and height. To analyze the risk factors related to hypertension, data, including patients' demographic and transplant characteristics, were reviewed. RESULTS Hypertension developed in 59 patients (38%), among whom 12 (7.6%) required long term therapy. Thirty-two (54%) patients had systolic and diastolic, 8 (14%) had only systolic, and 19 (32%) had only diastolic hypertension. Younger age, acute graft-versus-host disease, sinusoidal obstruction syndrome, treatment with antifungal agent, and greater increase in serum creatinine (Cr) levels were associated with hypertension. Multivariate analysis showed that younger age at HSCT and greater increase in serum Cr level were independent risk factors for hypertension. CONCLUSION Prevalence of hypertension during immediate post-HSCT period is high, especially in younger children. A greater increase in Cr after HSCT was significantly associated with hypertension. Further study is needed to elucidate long-term cardiovascular complications in pediatric HSCT survivors.