Enroll-HD: 10 Years Observing HD

 Written by the Moving Forward team on March 14th, 2023

Enroll-HD is the world’s largest observational study being conducted in HD. This study is promoted by the CHDI Foundation, Inc. to speed up the development of effective treatments for Huntington’s Disease. Enroll-HD aims to observe and monitor how HD affects people and how it changes over time. It is focused on collecting a huge amount of demographic, clinical and biological information from the worldwide HD community with three specific goals: enhance the understanding of HD, support clinical trials and improve clinical care.

Enroll-HD involves an annual visit to the clinic, where a set of tests and assessments are done to each participant to track their current health status. Information is collected every year, from the same people, using the same standard procedures, for a long time. Everyone from an HD family can be part of Enroll-HD, as participants include people with manifest HD, people with premanifest/prodromal HD, people at risk for HD, people who tested negative for HD, and people not at risk for HD (e.g., spouses, partners, caregivers).

The study has reached impressive numbers: more than 25.550 participants with 94.845 visits completed in 156 research units from 23 countries in Europe, North America, Australasia, and Latin America.

Enroll-HD also works as an extremely important clinical research platform, connecting persons with HD, families, researchers, clinicians and other healthcare professionals, patient advocates, and anyone else with an interest in HD. The incomparable worldwide database created through Enroll-HD serves as a very rich ground to conduct additional HD studies that will help understand the many aspects of the disease. In fact, researchers interested in expanding the knowledge about HD can request the data of this observational study to run their own studies. Hundreds of studies have already used the data provided by the Enroll-HD participants, to cover topics such as the effect blood pressure has on HD symptoms or the effect of HIV-infection in the rate of HD progression. The Enroll-HD database made it possible to create a new classification system for HD staging, to identify biomarkers and genetic modifiers or to pinpoint new therapeutic targets. Importantly, this could only have happened with the selfless and priceless contributions of the participants of this observational study – HD families.

Moreover, the Enroll-HD participation can open the door for taking part in other research opportunities, including clinical trials. The study is also a great chance for gene-negative individuals to make their contribution to the HD cause. The minimal requirements and low demands of this study make it ideal for people who are a little reluctant to participate in HD research or who do not comply with the strict criteria of many investigational studies in Huntington’s disease.

Enroll-HD is a tangible proof that joining forces is always the best way to achieve a common goal. Thanks to the efforts made during its predecessor observational study, REGISTRY, which started in 2004 and involved 140 European centers, the foundations were laid for Enroll-HD to now break all records of worldwide participation.

Additionally, the high standards of this study imply that the Enroll-HD centers meet strict and uniform quality requirements, which is reassuring for families. Participation in such well-organized observational studies is more than just research participation. For many HD families, it also brings the possibility of regular check-ups and contacts with clinicians. As the Moving Forward surveys have shown, families would like to have a closer connection with HD-experienced healthcare professionals and more regular visits to clinical sites. Enroll-HD covers this need, since HD families involved in this study have the chance to connect more often with healthcare professionals, particularly neurologists.

Eva, a young Spanish participant in Enroll-HD, wanted to share what it means for her to be part of this project: “Enroll-HD is one of the most important international projects currently focusing on Huntington’s disease. I believe that all families living with this disease should know about it and participate, as it is a very easy way to collaborate with future research and clinical trials by simply attending an appointment once a year and providing data anonymously. From this large pool of information, many hypotheses and conclusions can be drawn that can lead to improvements in our quality of life and, of course, in the search for treatments for HD”.

More details about Enroll-HD can be found here: