Stroke rates have fallen, study finds

(Medical Xpress)—The number of people suffering a stroke has steadily declined by forty per cent over the last 16 years, according to a major study by researchers at King's College London.

But the study, published in the journal Stroke, also highlights that the decrease in incidence has not been seen in young people or black people. The researchers say more needs to be done to understand the reasons for this if stroke is to be effectively prevented across the whole population.

The team analysed incidence of stroke from the South London Stroke Register, covering a population of more than 350,000. Between January 1995 and December 2010, 4,245 patients with first-ever stroke were registered. Researchers found that incidence fell by 39.5% between 1995 and 2010, from 247 per 100,000 population to 149.5.

The average age of onset of stroke decreased from 71.7 years to 69.6. However, there were significant increases in the proportion of 15-44 year-olds, from 5.1 per cent in 1995-98 to 8.4 per cent in 2007-10, and from 11.1 per cent to 19.9 per cent for those aged 15-54. The increased risk for younger people could be down to a rise in classical cardiovascular risk factors such as diabetes mellitus, obesity, and high cholesterol level.

The proportion of black patients also increased from 16.6 per cent to 25.6 per cent during the study period. The ethnic disparities may be because of different cardiovascular risk factors such as hypertension and diabetes mellitus. There may also be cultural differences in perceptions of health and the healthcare system, environmental exposures, genetic factors, socioeconomic status, and educational attainment.

Dr Yanzhong Wang, Lecturer in Medical Statistics, King's College London, said: "This study on the trends in stroke is the first and most comprehensive in the UK. It shows a 40 per cent overall reduction of stroke over 16 years, which is good news. However, we noticed strikingly higher stroke rates in black groups and in younger people aged 15-44. The reasons for this are not entirely clear but it could be because of a rise in diabetes and obesity in these groups. If this trend is not reversed we could face a major public health concern because long-term disability, as a result of stroke, will put a strain on health and social care services. National Strategies to prevent stroke should take these findings into account if we are to effectively prevent stroke across the whole population."

Professor Tony Rudd, Co-author from King's, said: "Stroke is the second leading cause of death worldwide. It is essential that we begin to understand the reasons for the differences in incidence and how we can address them. Without this, we are only going to see widening health inequalities amongst the UK population."