Interview with Natasha Appelman-Dijkstra

M.D. Ph.D., Leiden University Medical Center (LUMC), Netherlands

Who are you and what is your relationship to OI?Dr. Natasha Appelman

I am Natasha Appelman-Dijkstra internist-endocrinologist in Leiden University Medical Center and specialized in Bone and Mineral Disorders and thus treating patients with OI. I have worked in the Leiden University Medical Center (LUMC) for almost 10 years now and since the founding of the European Reference Networks (ERNs) our center has been involved in the European Reference Network on Rare Bone Diseases (ERN BOND). Since 2020 I am the coordinator of EuRR-Bone, where OI is an important part.

How did it start?

The EuRR-Bone project started in April 2020 officially. During the summer of 2019 we wrote the grant proposal for the EU to get funding for the registry. Faisal Ahmed is the lead for EuRRECa registry, which is the registry for the European Reference Network on Rare Endocrine Conditions (ENDO-ERN). Together with Faisal’s help and the connection to EuRRECa, we were able to develop a plan and got everything up and running rather quickly. At this moment we are funded for three years. In the meantime we are developing a sustainability plan.

Graphic Open access


Who owns and maintains the registry?

I am the custodian of the data, but in the end the patients always own the data. People can retract their information anytime. At this moment the servers are in Glasgow, Scotland, but we expect to host them in Leiden (The Netherlands) anytime soon. Maintenance is performed by our database creator and a team at Leiden University.

What is the purpose of the registry?

To collect data on rare bone and mineral conditions to learn more about the natural history of the different bone conditions, to evaluate the level of care throughout Europe and to gather patient related outcomes (PROMS). In the future the registry might be used for active surveillance of newly introduced drugs. It can be used to quickly identify potential subjects for studies and patients can use it to report on their disease and engage with the caregivers involved in the registry. Everybody who fills in a data request form can get access to the data if the request is deemed ok by the data access committee.

Can you explain about the different parts of the registry?

  • Core dataset
    Collects a core dataset with minimal information on patients: age, sex, way of diagnosis, mobility and height, EQ5D (quality of life).
  • The E-Rec
    Through the E-Rec we are counting new cases seen in a center for rare bone conditions.
  • The OI-module
    This is a disease specific module on OI. So next to the Core dataset, we will collect more details specifically on OI with the purpose to have a centralized registry throughout Europe and beyond with clinical and patient info on OI
  • Covid-19 module
    This module is counting new cases of covid19 in patients with a rare bone disease.

Graphic EuRR-Bone reporting centers

Who can contribute with data to the various parts?

Anyone who considers themselves as an expert center can contribute with data.

Are you thinking of developing some kind of “patient facing platform”?

Yes, patients can already have access to their data and fill out PROMS. The next step would be that we could also use that platform perhaps to pass information to patients etc.

Do you have some kind of interaction with other OI-registries?

We have interaction with the RUDY registry (UK) and iFOPA (registry for FOP), but not with specific OI registries yet.

What has been the biggest challenge when developing a registry like EuRR-Bone?

Getting everybody moving into the same direction and sometimes the lack of consent on definitions and local differences of approaches.

It’s been a year with EuRR-Bone now – what are you most happy with so far?

That the e-rec is working, core is being set up and we were able to decide on what to include in the modules. Despite the COVID 19 pandemic, everybody has been doing a great job.

Which impact did Key4OI have on the development of EuRR-Bone?

Key4OI has not impacted EuRR-Bone in general, but it did have an impact on the development of the OI module. Since Key4OI already went through all the phases with focus groups, we were able to have a quicker view of the potential items to collect. We were also informed on discussions that were already done on certain topics. It also made it clear for us, that we should decide on fewer items to collect, to ensure commitment from all centers in Europe. In addition, it made it clear that our niche should be to collect data that were not yet being collected.

What are the drop in sessions for?

Every other Friday at 14.00 CET, we have free drop in sessions online. They are there to give people answers or help with the registry or you can just drop by for a chat about the registry. Find out more on

If you had a magic wand to make your job with EuRR-Bone easier – what would you change?

I would like to have a fulltime datamanager/programmer, perhaps also an EU liaison or so to help people setting their ethics up in their own center and help them to start registering.

Any messages for the readers of the OIFE Magazine ?

I have to say that I am very impressed by the work OIFE is and has been doing. Not only the commitment from patient representatives in ERN BOND and EuRR-Bone, but also now with the help from OIFE with the LOVD OI variant database. I am really looking forward to intensify our collaboration with the EuRR-Bone module on OI and also to possible future projects.