Risk-seeking behaviour can increase when taking dopaminergic drugs in some. Who is affected and why?
Dr Stephanie Hirschbichler, MSc PhD, is the lead clinician of the movement disorder outpatient clinic at the Neurology Department of St. Pölten University Hospital. In addition to her clinical work, the Consultant Neurologist looks into the mechanisms behind changes in risk-taking behaviour and whether and how the risk-seeking behaviour of patients with different diseases changes when they take dopaminergic medications. Dr Uwe Graichen from the Department of Biostatistics and Data Science implemented an online task to quantify risk tolerance.
Dr Stephanie Hirschbichler, what exactly are you investigating in your research work and how did you come across the topic?
Stephanie Hirschbichler: I have been very involved in the field of Parkinson's disease, both as part of my current work as a clinician and during my PhD at the University College in London (UCL). Dopaminergic drugs are the golden standard in the treatment of Parkinson's disease. However, some patients experience massive adverse effects, especially when taking dopamine agonists. They may develop impulse control disorders (e.g., pathological gambling, shopping addiction, etc.). In this context, I investigated the risk-taking behaviour of healthy volunteers before and after ingestion of an (anti-)dopaminergic drug using a gambling task. This was done during my time as a research associate in London. We were able to show that even a single dose of a dopaminergic substance increases risk-seeking in healthy volunteers.
Dr Uwe Graichen, how are you involved in the research project? What is your contribution?
Uwe Graichen: To quantify the change in risk-taking behaviour, we implemented a simple gambling task with two decision options. In the individual game constellations, the chances of winning and losing as well as the possible gains and losses are varied. This makes it possible to quantify the patients' and volunteers' willingness to take risks. Until now, a similar task was only available in a non-online format (Rogers et al). In collaboration with Dr Hirschbichler, I implemented an online version of the task- i.e., a tool to quantify risk-taking behaviour. The implementation of an online game simplifies the conducting of studies considerably and significantly expands the number of patients and subjects who can participate in studies. Patients or subjects are sent a link and can participate in the study remotely. The task takes between 20 and 30 minutes.
Stephanie Hirschbichler: The fact that the game is now available online comes with many advantages. It allows us to involve rarer cohorts of patients and include them in our study. This way we can deepen the research in this field. Currently, we are conducting a study involving patients with cluster headache.
How exactly are the two topics - cluster headache and impulse control disorders under dopaminergic therapy - related?
Stephanie Hirschbichler: There is evidence that patients with cluster headache have a higher risk of traumatic brain injury and higher addiction potential. The reason for this is not yet sufficiently clear. We are currently assessing the risk propensity of patients with cluster headache and comparing it with that of a healthy population. Deep brain stimulation in the ventral tegmentum is used to treat therapy refractory cluster headaches in a selected cohort. This region of the brain is in turn part of important dopaminergic pathways. We seek to characterise whether and to what extent deep brain stimulation alters dopamine levels therein. So again, it's about dopamine and its likely effects. Ultimately, we aim to find a parameter for preselection: Will my Parkinson's patient benefit from therapy with dopamine agonists or is there a high risk of adverse effects on their quality of life due to impending impulse control disorder?
Uwe Graichen: The advantage of the current online gambling task is that we can adjust it relatively easily. So, we can adapt the measurement instrument to new and different questions.
