The hidden costs of rare diseases point to a data problem

More than 7,000 rare diseases are known, most of them have an identified genetic origin and many appear in childhood. Diagnoses are often delayed for years, and effective treatments are still lacking for the vast majority of conditions. This long-term uncertainty affects not only patients and families, but also health systems and economies.

The report “Making Rare Diseases Count: How Better Data Can Unlock a Multitrillion Dollar Opportunity” highlights how the full impact of rare diseases can remain hidden when data is scattered across registries, care providers and national systems. Without better data, decision-makers cannot see the full picture, or act on it.

The roadmap points to practical ways to strengthen rare disease data systems across different national contexts: agreeing on minimum datasets to improve comparability, supporting patient-driven registries, improving early diagnostics such as newborn screening and enabling secure data sharing while keeping governance local. It also points to how digital tools and AI can help generate insights even when datasets are small and dispersed.

The European Health Data Space (EHDS) is highlighted in the report as an example of an effort that helps reduce fragmentation, especially in the future as the regulation becomes applicable. The report includes a short case example on the EHDS and its implementation work under the TEHDAS2 joint action coordinated by Sitra.

“For rare diseases, where data is often scattered and patients face long diagnostic delays, enabling regulatory frameworks, like the EHDS, can be truly transformative. By improving data access and interoperability, we can make needs and outcomes more visible, accelerate innovation and ultimately shorten the path to diagnosis and care,” says Elina Drakvik, project lead of TEHDAS2 and contributor to the report.

Rare diseases are increasingly recognised as an international public health priority, reflected in recent United Nations and World Health Assembly resolutions. The report stresses that recognition alone is not enough: turning political attention into effective national responses requires data that makes needs, outcomes and costs both visible and usable. It further highlights that rare diseases are ultimately a health equity issue, where better use of data can reduce systemic inequalities and health disparities while also unlocking significant societal and economic value.