(Reuters Health) - Even stroke survivors who don’t experience any immediate complications are still more likely to die or have a heart attack than people who never had a stroke, a recent Canadian study suggests.

For the study, researchers examined data on 26,366 adults in the province of Ontario who had a stroke or a mini-stroke and didn’t experience any complications for three months. Over the next five years, they compared how many of these patients died, had a heart attack or another stroke, or were admitted to a long-term care facility to a control group of 263,660 people who never had a stroke but were otherwise similar in characteristics like age, gender and income.

After one year, 9.5 percent of the survivors died or had serious complications, compared with 5.4 percent of people in the control group, researchers report in the Canadian Medical Association Journal. After five years, 36 percent of stroke survivors died or had these complications, compared to 21 percent in the control group.

“The current study focused specifically on determining long-term risk for survivors who were ‘stable’ with no complications during the early highest-risk period right after a stroke,” said senior study author Dr. Richard Swartz, a neurologist at Sunnybrook Health Sciences Centre in Toronto.

“What was surprising was that, even those with no early complications after stroke were at twice the risk of adverse complications, with a 7-fold increased risk of recurrent stroke at one year, a risk that remained high for up to five years,” Swartz said by email.

The findings suggest that just like survivors of more serious strokes, these “low-risk” patients need ongoing screening and treatment to minimize the odds of problems down the line, Swartz said.

This might include taking blood thinners or medication to lower blood pressure or keep cholesterol levels in a healthy range, as well as lifestyle changes focused on a healthier diet, more exercise, less alcohol consumption and quitting smoking.

All of the stroke patients in the study were treated in between 2003 and 2013, and the control group was drawn from people living in the general population during that decade.

The study wasn’t a controlled experiment designed to prove whether or to what extent low-risk stroke survivors will experience repeat strokes or other complications over the long term.

Another limitation of the study is that researchers lacked data on the causes of stroke for patients in the study, which might influence their odds of death or a heart attack or repeat stroke in the future, the authors note.

“Stroke is caused by a multiplicity of underlying conditions,” said Dr. Michael Hill, author of an editorial accompanying the study and a neurology researcher at the University of Calgary. “These conditions can and do predispose people to other illnesses.”

“For example, a person might be a smoker and have concurrent lung disease and therefore have a greater tendency to pneumonia,” Hill said by email.

Even slight complications after a stroke can, over time, contribute to disability or a repeat stroke, heart attack or other serious complications, Hill added.

“It begins insidiously with each minor deficit or disability,” Hill said.

SOURCE: bit.ly/2uUrKxF and bit.ly/2tAuFHZ Canadian Medical Association Journal, online July 24, 2017.