While age-adjusted death rates from stroke have decreased worldwide, the numbers of people who have a stroke every year, who survive strokes, deaths related to strokes and disability-adjusted life years (DALYs) related to strokes have increased, especially in low- and middle-income nations. Most of the stroke burden has also shifted to adults younger than 75. These findings were published online Oct. 24 in The Lancet.

The authors used data from the Global Burden of Disease Study 2010. In their analysis of 119 studies from around the world (58 from high-income countries and 61 from low- and middle-income countries), they found a significant 12 percent decrease in age-adjusted stroke incidence between 1990 and 2010 in high-income countries. Incidence in lower-income countries increased by 12 percent, but not significantly. Mortality rates also significantly decreased in both high- and lower-income countries (37 percent and 20 percent).

The number of first-time strokes increased since 1990.

“Overall, in 2010, an estimated 16.9 million cases of incident stroke took place worldwide (69 percent in low-income and middle-income countries),” wrote the authors, led by Valery L. Feigin, MD, of Auckland University of Technology in Auckland, New Zealand.

There were also 33 million people who survived a stroke, 5.9 million deaths related to stroke and 102 million DALYs lost that significantly increased since 1990 (84 percent, 26 percent and 12 percent increases, respectively).  Low- and middle-income countries bore most of these increased burdens.

The analysis also revealed that strokes increasingly happened to younger people. The authors found a 25 percent global increase in strokes among people ages 20 to 64. In 2010, 5.2 million children (considered younger than 20 years of age) and adults ages 20 to 64 suffered a stroke. Again, this trend was noted mostly in low- to middle-income countries.

“The worldwide stroke burden is growing very fast and there is now an urgent need for culturally acceptable and affordable stroke prevention, management and rehabilitation strategies to be developed and implemented worldwide,” Feigin said in a press release.

In an accompanying comment, Maurice Giroud, MD, PhD, and two colleagues from the University of Burgundy in Dijon, France, wrote that the increasing burden among younger people is troubling.

“Although this increase was mainly because of an 18 percent increase in low-income and middle-income countries, data have also suggested similar trends in high-income countries,” they wrote.

Feigin et al’s study, they continued, indicates that the aging global population has led to an increase in the number of patients with stroke.

“Urgent preventive measures and acute stroke care should be promoted in low-income and middle-income countries, and the provision of chronic stroke care should be developed worldwide,” they argued.