Parkinson’s disease is usually considered to be a movement disorder characterized by tremor, rigidity, slow movement or poor balance. Yet when many people with Parkinson’s look back they can point to early changes in areas unrelated to movement, such as, loss of smell, lack of motivation, tiredness, and slower responses when answering questions. A visitor to the Parkinson Society Canada web site, http://www.parkinson.ca, who experienced these kinds of changes before the diagnosis recently asked: “Why isn’t there more information out there for doctors and the general public about the subtle signs of Parkinson’s so they can be monitored and diagnosed earlier?”
e-ParkinsonPost raised this issue of non-motor symptoms with Dr. Mandar Jog, director of the Movement Disorders Program at the London Health Sciences Centre and Dr. Ranjit Ranawaya, director of clinical services for the Movement Disorders Clinic at the University of Calgary. Here is some of what they had to say:
The clinical diagnosis of Parkinson’s disease relies on motor symptoms.
Dr. Jog: “You need to have two out of the three cardinal symptoms plus response to levodopa. Those are the clinical criteria. You cannot say somebody has Parkinson’s disease because they have constipation, depression, loss of smell or restless leg syndrome. So, if you have a diagnosis of Parkinson’s and you have some of those other things, then those are the non-motor symptoms of Parkinson’s.”
There is currently no way to tell which people, with non-motor problems, will go on to develop Parkinson’s disease.
Dr. Jog: “If you have constipation, loss of smell, a family history of Parkinson’s, exposure to well water, if the stars are aligned this way, it may be that you have higher risk of developing Parkinson’s but we don’t go out and screen for those things at this time.”
Dr. Ranawaya: “The problem is, if I see a patient with depression or anxiety, how do I know they might get Parkinson’s? At present, we don’t have any drug that will slow down the disease process, stop it in its tracks or stop someone from getting it. However, if we find a compound which does slow down Parkinson’s or stop it, then we would want to identify those individuals who are at risk, possibly by doing smell testing on them. But for now, let’s assume I do a smell test on someone and I realize they could be at risk of Parkinson’s, there’s not much I can do. There really needs to be good evidence that if you start treating a person with medication it’s going to make a big difference in the long run.”
Many people experience non-motor problems after they have been diagnosed with Parkinson’s.
Dr. Jog: “Having other associated physical symptoms is not unique to Parkinson’s disease.”
Dr. Ranawaya: “In terms of non-motor symptoms, they occur the majority of time after the diagnosis has been made, apart from some people with REM behaviour sleep disorder and a percentage of people with depression or anxiety. The non-motor symptoms accompany the patient with Parkinson’s as the disease progresses.”
Researchers are discovering that REM sleep behaviour disorder, depression /anxiety and changes in smell are among the non-motor problems that most commonly precede motor symptoms in Parkinson’s.
Dr. Ranawaya: “Studies by neuropathologist Heiko Braak show that Lewy bodies, a pathological marker for Parkinson’s disease, don’t start in the substantia nigra where dopamine is produced, but they start in the brain stem further down, probably in the autonomic area and in the olfactory bulb which deals with smell.” (The autonomic nervous system controls involuntary body functions.) “Then they ascend to affect the brain stem where we have the sleep/wake cycle. So many patients develop REM sleep behaviour disorder where they act out their dreams. Then they become Parkinsonian; they develop the motor signs. When the Lewy bodies go further up into the brain, they start affecting the mesolimbic system and the cortex, so that by the time a person develops Parkinson’s, they have probably had it for a long time. For the medical profession, it’s only now we’re recognizing that this is not just dopamine, that there are all these other neurotransmitters that are affected.”
Dr. Jog: “Some people, including myself, feel that some of these non-motor symptoms are actually symptoms of Parkinson’s. It just happens to have affected other systems earlier on, which makes Parkinson’s not simply a substantia nigra and dopamine disease but a multi-system disease where multiple areas of the body physiologically are involved.”
Armed with this new knowledge, many clinicians are paying closer attention to the non-motor symptoms of Parkinson’s and seeking ways to assist patients with their treatment and management.
Dr. Jog: “In the last little while we’ve realized that we need to treat patients more holistically and that symptoms such as swallowing problems, constipation, mild cognitive impairment, even depression, apathy and anxiety are equally important and they do have an impact on the general well-being of patients.”
Dr. Ranawaya: “In surveys of patients, we have found that they are more disabled from their non-motor symptoms than their motor symptoms and that these things contribute more to quality of life and are more important to patients. We don’t have remedies for many of the non-motor symptoms so this is becoming quite a conundrum.”
Parkinson Society Canada has a checklist to help you monitor changes in your Parkinson’s symptoms. Use the checklist to discuss changes with your health care professional.