Incidence of cardiovascular disease in Swedish healthy blood stem cell donors

The last 20 years has seen a steady increase in the use of Granulocyte Colony-Stimulating Factor (G-CSF) in healthy donors, to obtain peripheral blood stem cells for allogeneic stem cell transplantation. There has been a concern that G-CSF could potentially increase the risk of cardiovascular disease in donors after donation. In a Swedish national cohort study, we examined the incidence of new diagnoses of cardiovascular disease after donation, and all-cause death, in 1098 peripheral blood stem cell donors (PBSC) who donated between 1998 and 2014. By linking data from three Swedish national population-based registers; the Patient Register, the Multi-Generation Register, and the Cause of Death Register, we created a database on all cardiovascular disease diagnoses for 1098 PBSC donors, their 1222 siblings, and 854 bone marrow donors, and time of death for those that had deceased. For each PBSC donor, five population-based controls, with the same year of birth, sex, and county of residence as the donor, were drawn at random from the general Swedish population, using the Total Population Register, 5495 in total. Data linkage was performed at the Swedish National Board for Health and Welfare using national identification numbers, which were removed before delivery of the datasets for statistical analyses. The study was approved by the regional ethical review boards of Stockholm, 98–259, and Uppsala, 2016–497. The cardiovascular disease incidence for PBSC donors, 18.1 cases per 1000 person-years, was not different from matched population controls, 19.2 cases per 1000 person-years, hazard ratio 0.89 (95% confidence interval (CI) 0.75 – 1.06 , p-value 0.19), bone marrow donors or non-donating siblings, after a median follow-up time of 9.2 years. Mortality from any cause was registered for 32 of 1098 PBSC donors (2.9%) during follow up, compared to 240 of 5495 population controls (4.4%), hazard ratio 0.65 (95% CI 0.45–0.94, p-value 0.02). The long-term incidence of cardiovascular disease in healthy donors was not increased after peripheral blood stem cell donation with the use of G-CSF, and donor mortality after donation was lower than age-, sex and residency-matched population controls.