In addition, patients who'd lived in the United States longer tended to have poorer diabetes control.

One potential explanation is that those patients had more exposure to the typical U.S. diet, and its abundance of calories from processed foods, Testai said.

Dr. José Biller, a professor of neurology at Loyola University Chicago, agreed.

"Dietary changes are often attributed to acculturation, and food is often used as a metaphor for citizenship," said Biller, who is also a volunteer expert with the American Heart Association/American Stroke Association. "We are what we eat. Everyone benefits from reduced salt consumption, staying active and maintaining healthy lifestyles."

Biller also said patients may face "critical" obstacles that make it difficult to stick with medications, ranging from cost to co-existing medical conditions to their own beliefs about the drugs.

In some cases, Testai said, language can be a barrier. If doctors need to communicate through a translator, that can make it harder to form a solid provider-patient relationship, he explained.

Communication is key, Biller agreed. He added that health care providers need "cultural competency" and a skill for "active listening, and not talking down to patients."

On a broader scale, Biller said, people living in communities that are "health care deserts" need better access to quality care.

As for what patients can do, Testai emphasized diet changes, exercise and, when needed, weight loss.

"Medications are only part of the story," he said. "It's the sedentary lifestyle. It's the diet."

Testai pointed out that people do not need a gym membership in order to exercise. Getting physical activity throughout the day is what matters.

"Go out and walk around the block," he said. "Take the stairs instead of the elevator. It's about changing the overall lifestyle."

More information

The American Stroke Association has more on stroke prevention.