Smartphone tests could enhance the detection of Huntington's disease progression

A series of digital tests, carried out via a smartphone app, could enhance the detection of disease progression in Huntington's disease and improve the efficiency of clinical trials, finds research led by scientists at University College London (UCL) and Roche.

The research, published in Brain, highlights how digitising tests designed to measure the progression of motor symptoms in people with Huntington's disease can provide a sensitive and reliable way to track changes in the function of patients.

Once participants have completed five simple tests of movement control, including assessment of balance, finger tapping and involuntary movements, a Huntington's Disease Digital Motor Score (HDDMS) is calculated.

A lower HDDMS value indicates better motor function, while a higher HDDMS value indicates worse motor function.

By regularly performing the tests in their everyday lives, participants' disease progression can be monitored by doctors and researchers using the HDDMS.

The researchers hope that the HDDMS will help in clinical trials by allowing researchers to detect even small changes in symptoms – making it easier to evaluate the potential of new treatments.

It would also help researchers to detect disease changes with fewer participants, shortening study durations and potentially accelerating the development of new Huntington's disease therapies.

Our findings suggest that incorporating the HDDMS in clinical trials will help to give clearer answers about whether a potential treatment is working, with fewer participants or shorter lead times than conventional measures.

What's more, the fact that the HDDMS is evaluated in a five-minute assessment in people's homes makes it convenient and potentially more meaningful than in-clinic measures of motor impairment."

Professor Ed Wild, UCL Huntington's Disease Centre

Huntington's disease is a devastating, inherited neurodegenerative condition causing progressive loss of movement control, thinking and behaviour. There is currently no cure and existing treatments mainly focus on managing symptoms rather than slowing or stopping the disease itself. Promising new therapies are undergoing clinical trials – making the efficiency and accuracy of the HDDMS more important than ever.

Developing HDDMS and the smartphone tests

The HDDMS was developed by researchers at UCL and Roche using data collected from 1,048 people across four observational and interventional studies. From a large battery of novel digital tasks presented via a custom smartphone app, the researchers were able to distil the measurements that best predicted disease progression, resulting in the HDDMS battery.

By using the selected tests, the researchers found that the HDDMS was around twice as sensitive in detecting real changes in motor function as the currently most used clinical measure, the composite Unified Huntington's Disease Rating Scale.

Professor Wild added: "More sensitive tools to measure disease progression are particularly valuable in rare diseases like Huntington's disease. The fewer people there are who can possibly participate in clinical trials, the more important it becomes to minimise trial burden and size.

"Sensitive measurement tools like the HDDMS may therefore facilitate Huntington's disease research across the scientific community."

The new research underscores the growing role of digital biomarkers in neurological research and highlights the potential for technology-driven innovations in disease monitoring and drug development.

The HDDMS is available to academic and industry parties working on Huntington's disease via Roche Diagnostics.

Study limitations

The research has some limitations, including that all data has been collected from people participating in specific clinical trials. Therefore, the HDDMS has not been evaluated in people before symptoms onset, nor in people with advanced HD.

Additionally, while the HDDMS is sensitive to changes, more research is needed to confirm its ability to predict long-term functional decline.