TORONTO -- Researchers have found much deeper links between cardiovascular disease and the risk of cognitive impairment than were previously known, strengthening the message to Canadians that taking steps to prevent heart disease and stroke also protects the brain.
A study by researchers at the Heart and Stroke Foundation mapped the associations between heart disease, stroke and the development of vascular cognitive impairment, a condition resulting from diseased blood vessels that supply the brain.
"The most startling finding is that people with heart conditions have a significantly increased risk of vascular cognitive impairment and possibly dementia because of their underlying vascular disease," said Heart and Stroke CEO Yves Savoie.
In a report released Thursday, the authors outline their findings from an analysis of 2.6 million hospitalizations of Canadians with cardiovascular disease between 2007 and 2017. They found that people being treated for one cardiovascular condition were at increased risk for developing multiple related conditions that could result in hospital readmission or death.
"We found a lot more connections than anybody ever appreciated," said co-author Patrice Lindsay, noting that the research also included a review of previous studies on the issue in the medical literature.
Forty per cent of the patients were readmitted one or more times for a new related illness, the study found. Many progressed into serious illnesses and medical emergencies, with a greater proportion of women affected than men.
"It's not just living with the heart disease or the stroke, it's the increased risk in complications of having multiple conditions," said Lindsay, director of system change and stroke at the foundation. "And the fact that all of these put you at higher risk for dementia."
Jennifer Monaghan, 49, suffered a serious stroke almost seven years ago that temporarily paralyzed her right side and robbed her of speech. While she was able to learn to speak again with rehabilitation, she was left with permanent cognitive deficits.
The former lawyer and mother of two said she knows her cognitive function isn't what it once was.
"I often unknowingly use the wrong word or I can't come up with the word I want," Monaghan said from her home in Kelowna, B.C. "I find my memory isn't as strong as it used to be."
What's particularly baffling and frustrating for Monaghan was her lack of risk factors for stroke -- she had no family history, wasn't overweight, exercised regularly and ate a healthy diet.
Worse, she has now developed heart failure, a chronic condition in which the heart muscle is unable to pump enough oxygen and nutrient-rich blood to adequately meet the needs of the body and brain.
"Anybody I've seen for my health issues, nobody has sat me down and said they're related and I should be aware of how much at risk I am of developing another one," said Monaghan. "And I don't know what I should be doing to avoid more cognitive decline."
That was another concern raised by the Heart and Stroke report: the gaps in the health-care system.
Because the system is designed for the most part to address one disease at a time, patients with cardiovascular illness who are at risk for related conditions typically face lengthy waits to see different specialists for diagnosis and treatment.
Such lags can lead to worsening illness, Lindsay said. "We need more integrated care where patients can kind of do that one-stop shopping and not have those long delays between specialists."
The report also puts the onus on individual Canadians, urging them to practise primary prevention through healthy lifestyle choices.
"We need people to appreciate that if you go out and get your 10 minutes of vigorous exercise a day, it's not just to help your heart, it's to help your heart, prevent stroke and prevent or delay dementia," she said.
"With our aging population, when you look at it in this way, it's like a huge red flag -- we've got a huge problem on our hands. As people age, as the population gets older, we're going to see more and more of these conditions ... and our (health-care) system isn't really built to handle that."
Some other findings:
-- People with heart failure were 2.6 times more likely to experience vascular cognitive impairment, while those with the cardiac rhythm condition atrial fibrillation were 1.4 times more likely to experience VCI.
-- Those with heart valve disease were found to have a 25 per cent increased risk of vascular cognitive impairment.
-- And almost a third of patients who suffered a second stroke were at risk of developing VCI.
"It turns out that in the brain itself, new degeneration and vascular diseases are very closely intertwined," said neurologist Dr. Vladimir Hachinski, an expert in stroke and dementia at Western University.
"We're coming to realize that blood vessels of whatever size, whether they are the aorta or the coronary vessels, they are very closely linked to what happens in the brain," he said from London, Ont. "Because if they don't function, they cannot supply the brain well, and the brain suffers as a consequence."
