Several other risk factors were also associated with an increased risk of stroke, but impacted the odds of death or severe disability to a lesser degree. These included diabetes, high cholesterol, drinking alcohol, lack of exercise, unhealthy eating habits, stress, and excess body fat around the waist.
“Our findings emphasize the importance of controlling high blood pressure — which is the most important modifiable risk factor for stroke globally — along with managing atrial fibrillation and avoiding smoking,” says lead study author Catriona Reddin, MBBS, PhD, of the University of Galway in Ireland.
Factors That Increase the Risk of Severe Stroke
The study included almost 27,000 adults who were 62 years old on average, half of whom had experienced a stroke. Among those who did have a stroke, about 4,850 had a severe stroke, which the study defined as becoming unable to walk or attend to daily tasks like eating or getting dressed without aid, up to death.
People with high blood pressure were more than 3 times more likely to have a severe stroke than individuals without hypertension, according to study findings published in Neurology.
Atrial fibrillation, a heart rhythm disorder that can cause a rapid, irregular heartbeat, was associated with a more than quadrupled risk of severe stroke, while smoking was linked to an almost doubled risk.
Part of the reason high blood pressure may have an outsize impact on the risk of death and disability is because of the types of stroke it can cause, says Joshua Z. Willey, MD, a neurology professor at Columbia University Irving Medical Center in New York City, who wasn’t involved in the new study.
“In the case of hypertension, this is a leading contributor to hemorrhagic strokes, which tend to be more severe and have higher mortality,” Dr. Willey says. Hemorrhagic strokes are caused by a ruptured blood vessel in the brain and are much less common than ischemic strokes, which happen when a clot or fat deposit blocks a blood flow to the brain.
The Best Way to Prevent Stroke Is a Healthy Lifestyle
One limitation of the study is that researchers focused only on common so-called modifiable risk factors — things that people might have the potential to change to reduce their risk of severe stroke. They didn’t look at some common causes of severe stroke, such as chronic obstructive pulmonary disease or certain cancers, according to the study.
Even so, the findings offer fresh evidence of the importance of focusing on modifiable risk factors as a way not just to prevent stroke, but to minimize the damage these events can cause, says Trudy Gaillard, PhD, RN, an associate professor and health disparities researcher at Florida International University in Miami, who wasn’t involved in the new study.
“The most important thing a person can do to lower their risk of stroke is to manage and control their chronic health conditions,” Dr. Gaillard says. “Working closely with their primary care providers in controlling these modifiable risk factors is important.”
Taking medications to lower blood pressure and blood thinners to treat atrial fibrillation can both significantly lower the risk of stroke, Willey says. So can quitting smoking, getting 30 minutes a day of moderate-intensity activity like a brisk walk, and adopting a heart-healthy diet, such as the Mediterranean diet or Dietary Approaches to Stop Hypertension (DASH) diet, which both emphasize lean protein, whole grains, and fresh produce.
