Non-motor symptoms in Parkinson’s disease (PD) include depression, anxiety, sleep disorders, hallucinations/psychosis, cognitive dysfunction, apathy, dopamine dysregulation syndrome, impulse control disorders, and autonomic and gastrointestinal symptoms.
Neuropsychiatric symptoms in PD can be due to the pathologic brain changes, due to the emotional reactions to the disease process, and due to treatment-related side effects.
Depressive episodes or panic attacks precede the onset of motor symptoms in up to 30% of patients with PD (Santamaria Neurology 1986). As PD progresses, non-motor symptoms, rather than motor symptoms, are the main contributors to disability (Martinez-Martin et al, Movement Disorders, vol. 26, no. 3, 399–406, 2011).
The good news is that neuropsychiatric symptoms in PD can be effectively managed, resulting in a clear improvement in quality of life. Better managing non-motor symptoms (eg. anxiety) can also improve motor function.
Unfortunately, due to stigma, lack of awareness and other factors, many patients miss out on receiving optimal management for their neuropsychiatric symptoms. Treatment outcomes are improved if symptoms are identified promptly and evidence based treatment strategies are instituted early. Hence, it pays to be pro-active and to keep an eye out for these symptoms.
A good approach is for you (and other key supports, such as your partner) to learn more about these non-motor symptoms in case they develop at a later stage. There are a number of good resources, but the DASH handbook is a good place to start: http://www.parkinsonsnsw.org.au/wp-content/uploads/2015/03/DASH_Booklet.pdf.
If you do develop any of these very common neuropsychiatric symptoms, a good person to speak to in the first instance is your local doctor. Your local doctor will then co-ordinate your management. This commonly involves first seeking the input and specific skillset of a range of specialists, such as your neurologist, a psychiatrist, neuropsychiatrist or psychologist. A comprehensive management plan will then be tailored to your specific situation that addresses biological factors (e.g. reviewing your medication), psychological factors (e.g. a talking-based therapy), social and lifestyle factors.
If we take the example of depression or anxiety in PD, your neurologist would assess the possibility that hypodopaminergic states (e.g. too low a dose of your PD medications) might be contributing to symptoms such as depression, anxiety and apathy. Mood and anxiety symptoms can be quite different in the ON and OFF medication state (particularly as PD becomes more advanced), so this is another thing that your doctor will assess.
As well as PD being associated with the loss of dopamine producing neurons in the substantia nigra, it has been demonstrated that there can also be loss of noradrenergic neurons in the locus coeruleus and loss of serotonergic neurons in the raphe nucleus. These neurotransmitters both play an important role in the regulation of mood and anxiety. More marked degeneration in these regions has been demonstrated in PD patients with depression vs PD without depression (Ehgoetz et al. J Neurol Sci 2017). Hence, there may be a role for commencing an antidepressant medication, which, amongst other things, can increase the availability of serotonin. The need for such antidepressant medication would need to be assessed by your doctor, with specialist input for a psychiatrist or neuropsychiatrist often being helpful. Neuropsychiatry is a field of medicine that deals with the overlap between neurology and psychiatry.
Major depressive episodes in PD occur alongside an anxiety disorder in 65% of patients (Ebmeier, Advances in Biological Psychiatry 2012). A number of psychological therapies have been shown to be effective in the management of both depression and anxiety. These evidence-based therapies include Cognitive Behavioural Therapy (CBT) and mindfulness-based cognitive therapies. These therapies can be delivered by either a psychologist or a psychiatrist, and your GP may refer you for such a talking-based therapy. The tools that you would learn to manage depression and anxiety will have enduring benefit.
For managing the non-motor symptoms of PD, there is good evidence now for the role of exercise. Psychologically, this can also be quite empowering. For example, in can help patients feel that they are taking back some control in their life by potentially modifying the course and impact of PD. Hence, if it is physically possible (and after discussion with your doctors), it is helpful to set a goal for regular exercise and to incorporate this into a written plan for the week. There are a number of group-based, PD-specific, exercise programmes that you can talk with your doctor about.
Finally, it is also worth considering learning some mindfulness meditation skills, which can be very useful for managing anxiety and the impact of PD on your life. There are now many apps that you can use to learn these skills. The Headspace app is quite a good one https://www.headspace.com/headspace-meditation-app.