STROKE rates are soaring among young and middle-aged people around the world, a study has shown.

In 20 years, the number of strokes afflicting people aged 20 to 64 rose by a quarter, researchers found.

Strokes suffered by this age group now make up 31% of the global total, compared with 25% prior to 1990.

For the first time, researchers also studied stroke rates among children and young people aged 20 and under.

They found that each year, more than 83,000 people in this age group were affected by stroke, 0.5% of the total number of cases.

If the current trend continues, the amount of disability, illness and premature death caused by strokes is expected to double worldwide by 2030.

Stroke Association chief executive Jon Barrick described the research as a "wake-up call to governments across the globe".

He said: "Rising obesity and diabetes rates, coupled with sedentary and unhealthy lifestyles, could wipe out the improvements we've seen in reducing stroke mortality in the UK, putting even more pressure on our limited NHS resources.

"This is a stark warning. We urgently need to address this global stroke crisis by prioritising stroke prevention and investment into stroke research."

The findings, from a major analysis of stroke burden around the world, are published in the latest issue of The Lancet medical journal.

The research forms part of the Global Burden of Disease Study 2010, a systematic analysis of data on major diseases and causes of ill health in 50 countries.

The results reveal stark differences between rich and poor. Between 1990 and 2010, strokes were associated with 46% more disability and illness and 42% more deaths in poorer than in richer countries. In high income countries, stroke rates fell by 12% over the two decades.

Lifestyle risk factors such as smoking, high blood pressure, and unhealthy diet were thought to play a role in increasing stroke burden in low-to-middle income countries.