Health Conditions That Increase Stroke Risk Rise Across All Ages, Races

For years, doctors have been warning us that high cholesterol, cigarette smoking, illegal drug use and diabetes increase our chances of having a potentially fatal stroke.

And yet, most of the stroke patients showing up at hospitals from 2004 to 2014 had one or more of these risk factors. And the numbers of people at risk in this way tended to grow among all age groups and ethnicities in that time period.

That's according to an analysis of the charts of more than 900,000 people admitted to U.S. hospitals for stroke within that decade. The study was published Wednesday in the journal Neurology.

"An estimated 80 percent of all first strokes are due to risk factors that can be changed — such as high blood pressure — and many efforts have been made to prevent, screen for and treat these risk factors," says neurologist and study author Dr. Fadar Oliver Otite of the University of Miami Miller School of Medicine. "Yet we saw a widespread increase in the number of stroke patients with one or more risk factors."

Most surprising, researchers say, was the high rate of Hispanic stroke patients who also had diabetes — about 50 percent — and African-American stroke patients, 44 percent of whom also had diabetes.

"Those rates are really very alarming" for a variety of complex reasons, says Dr. Seemant Chaturvedi, who also worked on the study and is a professor of clinical neurology at the Miller School of Medicine. Poor diet, less access to health care, lack of exercise and other factors all can contribute to risk, he says.

"Those are populations that need to be looked at," Chaturvedi adds.

But not all of the risk factors increased equally, or can be attributed to the same causes, he notes. Diabetes increases many of the other risk factors, and this country is still in the midst of a diabetes epidemic, although recent studies suggest it may have reached a plateau.

Other risk factors may simply appear to be increasing because doctors have become more tuned in to checking for them.

For example, stroke patients with dislipidemia (a fancy way of saying an imbalance of fat and other substances in the blood) nearly doubled during that decade, although that is probably because doctors are testing for the condition and treating it more often. High cholesterol has become an increasingly important factor in stroke risk, Chaturvedi notes.

Given the demographics of the opioid epidemic the U.S. is struggling with, it's probably not too surprising that stroke risks are rising among younger people. The prevalence of drug abuse among stroke patients doubled from 1.4 percent in 2004 to 2.8 percent by 2014, the study shows.

It's really important that younger and middle-aged people understand that "these behaviors do put them at risk" for stroke, and that stroke is no longer just a disease for older people, Chaturvedi says.

The findings add to a growing list of recent studies showing stroke is an increasing problem among young to middle-aged adults.

The study also found that the prevalence of diabetes across stroke patients of all ages and ethnicities increased by 22 percent — from 31 percent of patients in 2004 to 38 percent in 2014. And the prevalence of high blood pressure increased by 15 percent — from 73 percent of patients at the beginning of the study period to 84 percent by the end.

According to the American Heart Association, stroke is the second-most-common cause of death from cardiovascular disease, although rates of stroke deaths decreased between 2004 and 2014 by almost 29 percent. However, if stroke risk factors are increasing, that's a trend to watch.

Chaturvedi says the authors would next like to study data coming in from 2011 to 2016 to see if the risk factor rates change.

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