Effective Approach Boosts Willingness to Donate Stem Cells
Every year more than 20,000 people in Germany die from blood cancer. Blood cancer is actually the most common type of cancer in children. Donations of stem cells from bone marrow or blood increase the chance of survival for people suffering from leukemia or other forms of blood cancer. However, years can pass between the registration of those wishing to donate and their actual donation. Many volunteers are hesitant when it comes to actually having the stem cells removed. An international team of researchers has now proven that renewed contact between registration and donation significantly increases the availability of donors. This effect is strongest when a blood sample is also requested.
The results have been published in the American Journal of Health Economics and provide important information for donor registries worldwide to improve their placement rates. Researchers from the University of Tübingen, Johns Hopkins University, the University of Technology Sydney, the universities of Cologne and Essen-Duisburg as well as employees of the world’s largest donor database DKMS were involved in the study.
The DKMS has a register of more than 12 million donors in the USA, Germany, Poland, Great Britain, South Africa, Chile and India. The researchers were able to evaluate a data set of 91,670 people willing to donate from 2013 to 2018 whose biological characteristics matched those of a patient with blood cancer. They were then asked again about their willingness to donate stem cells as part of the so-called confirmation typing, one of the central steps on the way to stem cell donation. The DKMS contacted some of these people with different letters with the aim of asking for additional data or blood samples. For example, the recipients were asked to update information about previous illnesses or to note stays abroad and pregnancies that would have prevented a donation in an emergency. A subgroup should also submit an additional blood sample for retyping in order to complete the genetic information. The other registered people were not contacted again by the DKMS for cost reasons and formed the control group for the study.
When a blood sample was requested in addition to the renewed letter, the number of registrants who later shied away from donating fell by 37 percent. “It is amazing that we were able to identify such positive effects despite the additional effort involved in taking a blood sample. By contacting them again, the donors are made aware of their opportunity to help and they probably feel more motivated as a result,” says Professor Patrick Kampkötter from the Department of Economics at the University of Tübingen, explaining the results of the study.
“We at DKMS knew that every additional contact with potential donors during the study period was important – but not that the increase in their availability was that much higher. Now this finding has been scientifically proven and evaluated and every donor register can consider whether the costs of the additional effort for renewed contact are proportional to the effect,” says Dr. Dr. Alexander Schmidt, Chief Medical Officer at DMKS.
Unlike a simple blood donation, with a stem cell donation a “genetic twin” must be found between the donor and the recipient, in which twelve specific genes must match – otherwise the risk of a fatal immune system in the recipient is too great. Once this “genetic twin” is found – if necessary after a worldwide search – and the donor part drops out or is not available at all due to a trip or pregnancy, the database loses valuable time searching for another match. In the meantime, the chance of survival for patients with blood cancer who urgently need suitable stem cells for their therapy is decreasing. Being able to distinguish the availability of donors in advance and increasing their motivation saves a donor register valuable time.
A common ethnic origin between donors and recipients also increases the likelihood of a genetic match. Statistically speaking, the willingness to donate varies considerably between ethnic groups. In Germany, 75 percent of those registered with the DKMS are willing to donate in an emergency, in the USA on average only half, and among some ethnic groups such as African Americans or Hispanics only around 30 percent. “Therefore, improved availability of stem cell donors for donor registries in countries like the USA is of particularly great medical and economic benefit,” says Prof. Mario Macis from Johns Hopkins University in Baltimore, Maryland, USA.