Potential Hazards for Haematopoietic Stem Cell Donors

The aim of this thesis has been to increase our knowledge about the allogeneic stem cell donation procedure and the associated risks for stem cell donors. In a first study (paper I), we described the donation procedure and short-term side effects of 1957 donors included in the Nordic Register of Haematopoietic Stem Cell Donors. Donors of bone marrow or peripheral blood stem cells experienced side effects such as bone/muscle pain, headache and /or fatigue in more than 90% of cases, with symptoms lasting less than one week for the majority of donors. Bone marrow donors had side effects of longer duration, experienced more fatigue, and were more likely to need sick leave longer than one week. Related donors were older than unrelated donors, had more comorbidities, and more frequently needed a central venous catheter and/or multiple apheresis during peripheral blood stem cell donation. For a second study (paper II), we analysed global survey data from the World Marrow Donor Association (WMDA), regarding the use of biosimilar versions of stem cell mobilising drug filgrastim. A third of donor registers (10/30) had adopted the use of biosimilar filgrastim, with the majority doing so during the last five years. A review of studies of biosimilar filgrastim use for healthy donor stem cell mobilisation, showed biosimilar drugs to exhibit similar pharmacokinetic and pharmacodynamic properties to the reference product Neupogen®. No differences in stem cell mobilising capacity or adverse events were found. The study resulted in the endorsement by WMDA of the use of biosimilar filgrastim for stem cell mobilisation in healthy donors. In two studies (paper III and V) of almost 1100 donors, we linked data from multiple Swedish national registers to investigate if peripheral blood stem cell donation with the use of granulocyte-colony stimulating factor (G-CSF) is associated with an increased risk of cancer or cardiovascular disease. No increased risk of cancer, haematological malignancies or cardiovascular disease was found, after a median follow up of close to 10 years. In a national survey of 210 potential stem cell donors, using validated mental health screening tools (paper IV), we found female gender, lower age, and an increased level of worry for one-self in regards to becoming a donor, to be associated with lower mental health, and higher levels of anxiety.