Brain Sunnybrook Magazine - Spring 2018

Risk of a second stroke doubles for up to five years

Risk of a second stroke doubles for up to five years

After a person experiences a stroke or mini-stroke, the likelihood of having another is significant. This risk is highest early after the first stroke – in the first year, 15 times greater than for the general population.

Due to this high early risk, the major focus of stroke-prevention efforts for stroke survivors has been to closely follow them to avoid complications within a 90-day period. Those without early complications are then typically discharged from specialist stroke-prevention services within six months with recommended long-term prevention strategies.

But according to a recent study by stroke researchers at Sunnybrook, published in the Canadian Medical Association Journal, even initially stable individuals remain at substantial long-term risk for future strokes.

“For someone who survives a stroke or mini-stroke and is initially free of complications, the risk of experiencing another stroke, a heart attack, dying or requiring admission to a care facility is doubled for up to five years,” says Dr. Jodi Edwards, who was a postdoctoral fellow in the Canadian Partnership for Stroke Recovery at Sunnybrook and the Institute for Clinical Evaluative Sciences.

The research suggests that aggressive risk-factor reduction is necessary even after years of stability. “Stroke-prevention efforts are required for a longer period than initially thought,” notes senior author Dr. Richard Swartz, a neurologist at Sunnybrook. “There is a real need to maintain risk-reduction strategies, medical support and healthy lifestyle choices over the long term, even years after a mild initial event.”

Strokes 101

A mini-stroke – also known as a transient ischemic attack (TIA) – occurs when blood flow to a part of the brain is reduced or blocked, but symptoms resolve quickly. TIA is a potential warning sign of an impending permanently disabling stroke.

Long-term risk-reduction strategies for a recurrent stroke should include:

  • managing blood pressure, cholesterol and blood sugar levels;
  • detection and treatment of irregular heart rhythms;
  • smoking cessation;
  • maintaining a healthy body weight, regular exercise and a healthy diet; and
  • treatment of other, sometimes rarer, underlying stroke causes or risk factors, such as cardiac-related stroke and blood vessel problems.