The world is facing a stroke epidemic as risk factors increase in low and middle-income countries and the population ages, according to a leading WA neurologist.
UWA professor of neurology Graeme Hankey wrote a comment piece in the journal Lancet Global Health in which he argues that people living in low and middle-income countries are bearing the brunt of death and disablement due to stroke.
He wrote that more strokes, more stroke-related deaths and more disability-adjusted life-years occurred in these countries and that stroke affected people an average of six years younger.
The comment piece accompanied a systematic review of 119 stroke studies published between 1990 and 2010.
Professor Hankey, who also works at Sir Charles Gairdner Hospital, says that although the rate of stroke is falling, the world is facing a looming epidemic because of the growth and ageing of the population.
"There's so many more older people now than there used to be but [the review] also found that the number of younger people with stroke is increasing," he says.
"That's probably for several reasons but one of them is in Asia, where two-thirds of the world's population is, is becoming increasingly urbanised and there's more cardiovascular risk factors and stroke risk factors.
"Smoking's not stopping in Asia but obesity's increasing, diabetes is huge and increasing.
"In India where there's over a billion people, diabetes is just going wild and in China, where there's over a billion people, there's a huge amount of high blood pressure and bleeding into the brain."
Prof Hankey says the review found most of the global burden of stroke was due to haemorrhagic stroke.
Haemorrhagic stroke is a burst blood vessel in the brain, as opposed to ischemic stoke, which is a blocked blood vessel in the brain.
The review found that in high-income countries such as Australia about 20 per cent of strokes were haemorrhagic but in low and middle-income countries it was 37 per cent.
"In China and the Philippines and all throughout Asia … haemorrhagic stroke is quite a common type of stroke because blood pressure is so poorly controlled," Prof Hankey says.
"Also Asian people have some predisposition to high blood pressure."
The review found haemorrhagic strokes were more likely to be fatal, causing 52 per cent of stroke-related deaths, and accounted for 62 per cent of disability-adjusted life-years because it affected people at a younger age.
Prof Hankey says education and legislation have been effective at targeting high blood pressure, smoking and cholesterol in high-income countries but public health campaigns are needed in low and middle-income countries.
More information: "Global and regional burden of stroke during 1990–2010: findings from the Global Burden of Disease Study 2010." Prof Valery L Feigin MD, Prof Mohammad H Forouzanfar MD, Rita Krishnamurthi PhD, et al. The Lancet - 24 October 2013. DOI: 10.1016/S0140-6736(13)61953-4