LAUSR

Allogeneic hematopoietic stem cell transplantation (aHSCT) represents a therapeutic choice for high‐risk and relapsed leukemia at a young age. In this retrospective population‐based study, we evaluated cardiovascular complications after aHSCT (N = 272) vs conventional therapy (N = 1098) among patients diagnosed with acute lymphoblastic or acute myeloid leukemia below 35 years between 1985 and 2004. Additionally, siblings from a prior comparison group served as population controls (N = 39 217). Childhood leukemia and aHSCT was associated with a 16‐fold HR for developing arterial hypertension (HR 16.8, 95%CI 1.5‐185.5) compared with conventional therapy. A 2‐fold HR for any cardiovascular complication was observed after AYA leukemia and aHSCT vs conventional treatment (HR 2.7, 95% CI 1.4‐5.1). After AYA leukemia and aHSCT, the HR of cardiac arrhythmia was significantly elevated vs conventional therapy (HR 14.4, 95% CI 1.5‐125.2). Moreover, after aHSCT in childhood, elevated hazard ratios (HRs) were found for cardiomyopathy/ cardiac insufficiency (HR 105.0, 95% CI 10.0‐1100.0), cardiac arrhythmia, and arterial hypertension (HR 20.1, 95%CI 2.5‐159.7 and HR 20.0, 95%CI 4.1‐97.4) compared with healthy controls. After adolescent and young adult (AYA) leukemia and aHSCT, markedly increased HRs were observed for cardiac arrhythmia (HR 29.2, 95%CI 6.6‐129.2), brain vascular thrombosis/ atherosclerosis and cardiomyopathy/cardiac insufficiency (HR 23.4, 95%CI 7.1‐77.4 and HR 19.2, 95%CI 1.5‐245.2) compared with healthy controls. As the cumulative incidence for cardiovascular complications rose during the follow‐up of childhood and AYA leukemia patients, long‐term cardiovascular surveillance is warranted to optimize the quality of life after childhood and AYA leukemia following both conventional treatment and aHSCT.