PPMI Dispatch: New Tool to Measure Risk of Impulse Control Disorders in Parkinson’s
Friday, 28th October 2022

The Michael J. Fox Foundation’s (MJFF) landmark study, the Parkinson’s Progression Markers Initiative (PPMI), continues around the world.

Recent research focuses on specific groups of interests, in areas ranging from impulse control disorders (ICDs) to REM sleep behaviour disorder (RBD) to predict and measure Parkinson’s. Data from PPMI continues to lead to innovative research and impactful results that help scientists and doctors better understand and treat Parkinson’s disease.

As scientists continue to analyze PPMI data and share new findings, we share recent activities and findings using PPMI data.

A Tool to Predict Impulse Control Disorders in Parkinson’s

Some Parkinson’s medications can lead people to develop impulse control disorders. Related behaviours can include compulsive shopping, gambling, eating and sexual activity. Newly published research, funded in part by MJFF, suggests that genetics can help predict which people are most likely to have an ICD. A team at the University of Pennsylvania, with personal genetics company 23andMe, created a tool to predict ICD risk by looking at data from PPMI and other studies. That scoring tool may help people select the most appropriate Parkinson’s medication based on their ICD risk, as some treatments are more likely to lead to ICDs than others. This provides an opportunity for health care providers to stay one step ahead when caring for people with Parkinson’s disease (PD).

Brain Changes with RBD and Cognitive Impairment

Some people with PD have thinking and memory problems beyond what is expected with normal aging. This is called cognitive impairment. These changes can be more common in people with Parkinson’s who act out their dreams, a condition called REM sleep behavior disorder. Researchers in Spain found significantly more changes in brain scans from people in PPMI with both PD and RBD (compared to people with PD without RBD or control volunteers). These changes correlate with cognitive impairment, including problems with processing speed and word finding. These results suggest the need for cognitive screening earlier for people with RBD. They also could help scientists develop and test new treatments.

Progress in Biomarkers

Scientists continue to examine various biomarkers, or objective indicators of disease. Neurofilament light (NfL) is a protein released when brain cells are damaged. A paper published by Frontiers in Neuroscience suggests that elevated levels of NfL could predict worsening motor symptoms. Researchers of this study collected samples from PPMI participants with PD and control volunteers over three years. Results showed that NfL could be used as an easily accessible biomarker to monitor disease and progression of motor symptoms. The results also could help doctors with prognosis and possibly inform clinical trial design.

Better Understanding of Disease Risk

PPMI data are also helping scientists look at what symptoms may appear before the cardinal motor symptoms of tremor, slowness and stiffness. Investigators used PPMI data to explore the connection between autonomic symptoms and Parkinson’s risk. Autonomic symptoms include issues with nonvoluntary bodily processes, such as gastrointestinal issues, low blood pressure, sexual problems, urinary issues or sweating problems. The data suggest that gastrointestinal issues and female sexual dysfunction are associated with increased risk of a Parkinson’s diagnosis, especially if an individual is living with multiple risk factors. These data are useful in understanding early signs of disease and could help researchers pick the right participants for prevention studies.

PPMI helps us better understand and fulfill the unmet needs of people living with Parkinson’s disease. Whether you have PD or not, join the study that could change everything.

Shake It Up together with our partners at The Michael J. Fox Foundation funded the initial phase in Australia. It’s exciting to see the impact this study continue around the world. The study has been instrumental in understanding the disease, risk factors, biomarkers, and, most importantly, new therapeutics in patient hands.