This doctor spent years studying a disease he didn't know he had

A Halifax doctor who researched Parkinson's disease for years before realizing he had the condition says his own experienceshows how difficult it can be to catch early signs of the disease.

Dr. Harry Robertson spent decades studyingthe role dopamine plays in insects and people with schizophrenia, and more recently studyingpre-clinical markers for Parkinson's disease.

But it wasn't until he participated in a colleague's research study in about 2009 that he realized his fading sense of smell was a common non-motor symptom of the disease.

"Upwards of 95 per cent of all patients with Parkinson's disease present with loss of sense of smell," he said in an interview.

The professor emeritus at Dalhousie University's departments of pharmacology and psychiatry continued hisresearch on the disease, with a focus on dopamine's role.

Movement is normally controlled by dopamine, a chemical that carries signals between the nerves in the brain. When cells that normally produce dopamine die, the symptoms of Parkinson's appear.

"I was interested in developing drugs or treatment for Parkinson's disease," he said.

Meanwhile, he noticed he was clumsier than usual. After a walk in P.E.I.,he struggled with the steps off the beach.

"I was prone to clumsiness anyway, but this was beyond clumsy," he said. "Some delicacy about my balance and my loss of smellmade me think I should probably speak to a neurologist."

In 2015, his neurologist diagnosed him with Parkinson's disease in an early stage. Robertson said loss of smell usually precedes other symptoms, like movement disorder,by between two and five years.

He took his diagnosis in stride. "I didn't find anything special about it," he said. "We're not here forever and something has got to turn up."

He and his wife, Elizabeth Townsend, had just moved from Halifax to retire on a P.E.I. farm.

They had to move back to Halifax to be near treatment. His thoughts at times get lost in a sudden mental fog, he said, and he loses his place in a sentence when speaking.

"It's meant big changes in the family. My wonderful wife has accepted all sorts of difficult tasks in looking after me. Not that I think I'm very difficult to manage," he said with a smile as his wife laughed.

He plans to keepresearchingParkinson's disease until the condition physically prevents him from working. Dalhousie recently established theHarold A. Robertson Award in Parkinson's Disease Research to support new work in his name.

April is Parkinson's awareness month and Robertson has a message for anyone diagnosed with the condition. "It is what it is," he said. "You're not going to change things very much, so you might as well find ways of dealing with it."

He said nobody knows why, but good evidence shows physical activity reduces the impact. "So don't despair. Sign up for a gym membership or taking up cycling," he said.

He intends to walk the course of Hadrian's Wall in northern England when travel is permitted again.

100,000 Canadians have Parkinson's

Karen Lee is the president and CEO of ParkinsonCanada. She said about 100,000 Canadians live with the disease. She said most people are diagnosed around 60.

Lee said the disease causes tremors, impaired balance, and people feel slow and stiff. They can also experience fatigue, soft speech, depression and sleep disturbances.

"We still don't know what causes Parkinson's disease," she said. "Exercise can benefit people living with Parkinson's, as well as diet and mental health."

There is no test for the disease. Instead, it's a conclusion medical professionals reach after studying a patient's medical history and ruling out similar conditions.

There is no cure,but medication and activity can treat the symptoms for years.

"We've seen great results in terms of people doing boxing, dancing, as well as biking," she said.

She said there are resources to help people deal with depression and anxiety resulting from the condition.

"They're a resilient community," she said. "They might have the shaking, they might have the tremor, but they are still strong."