Parkinson’s disease: More than shaking going on
Researchers discovering non-motor symptoms may happen first
Parkinson’s is much more than a tremor.That’s a message Parkinson Society Canada hoped to drive home this April during Parkinson’s Awareness Month.
In Parkinson’s, the most common symptoms are movementrelated: tremor, slowness, muscle stiffness and balance problems.
However, by the time Parkinson’s is diagnosed, people have already lost 60 to 70 percent of the dopamine-producing cells. Now researchers are discovering that non-motor symptoms such as sleep problems, depression and smell loss may represent the earliest signs of Parkinson’s, for some people, and may appear years before the diagnosis.
In research at Montreal’s SacréCoeur Hospital, Dr. Ronald Postuma, assistant professor of neurology at McGill University found that people with a rare sleep disorder where they physically acted out their dreams had a 50 per cent risk of developing Parkinson’s disease or dementia within 12 years. The patients had REMsleep behaviour disorder, which Postuma describes as “punching and yelling or kicking out while asleep. It mostly affects people in their 60s and 70s, almost always men.”
Not all will develop a neurodegenerative disease but Postuma says, “Patients with true REM-sleep behaviour disorder have a considerable risk of developing Parkinson’s disease.”
Depression and anxiety can surface early in Parkinson’s.
“Many people, as they’re starting to lose their dopamine, may not yet have developed a tremor, slowness or trouble walking, but may feel anxious and depressed,” says Dr. Susan Fox, assistant professor of neurology at University of Toronto.“Depression is also part of Parkinson’s disease itself and not just a reaction to having a chronic neurological disorder.”
Fox notes untreated depression can reduce quality of life.
Smell loss is a common occurrence.
“The general consensus is that the changes in olfaction (sense of smell) occur about five years before the Parkinson’s diagnosis,” says Dr. Harold Robertson, a professor in the Brain Repair Centre and Department of Pharmacology at Dalhousie University in Halifax. “That could give us enough lead time to try to stop the process.”
Joyce Gordon, Parkinson Society Canada president and CEO says, “The more dollars we can put towards Parkinson’s research, the sooner we may be able to establish if there is a definite link to Parkinson’s when a person has sleep problems, depression or loss of smell.This would lay the groundwork for developing treatments to delay or stop this debilitating disease in its tracks. The answers can’t come soon enough for the 100,000 Canadians who have Parkinson’s disease and those who are unknowingly at risk.”
In the meantime, the first step for anyone experiencing difficulties with sleep or mood is to see a doctor for a proper diagnosis. REM sleep behaviour disorder and depression are treatable. Smell loss is not currently treatable but is worth mentioning to the doctor, during a routine visit, as it may be due to a variety of causes.