'We confirmed that lower wealth, education and income are associated with increased stroke up to age 65, and wealth is the strongest predictor of stroke among the factors we looked at,' Dr Mauricio Avendano, who was involved in the research, noted in a written statement.
'After age 65, the association of education, income and wealth with stroke are very weak, and wealth did not clearly predict stroke,' said Dr Avendano, of Erasmus Medical Center, Rotterdam, The Netherlands.
Each year about 780,000 Americans suffer strokes; about 27 per cent of strokes occur before age 65, according to the American Heart Association.
Dr Avendano and co-investigator M. Maria Glymour assessed the effect of income (i.e., annual earnings), wealth (total of all assets minus liabilities) and education on stroke risk in 19,445 Americans in the ongoing University of Michigan Health and Retirement Study (HRS), which surveys Americans age 50 and older every two years.
All of them were stroke-free when they entered the study in 1992, 1993 or 1998. During an average of 8.5 years, 1,542 people in the study had a stroke.
Dr Avendano and Dr Glymour report in the American Heart Association's journal Stroke that the 10 per cent of people with the lowest wealth had three times the stroke risk at age 50 to 64, compared with those with the highest wealth.
'Lack of material resources themselves, and particularly wealth, appear to strongly influence people's chances to have a first stroke,' Dr Avendano said. 'From a public health perspective, this would mean that diminishing the large wealth gap at age 50 to 64 also could help diminish the large disparities in stroke.'
However, as noted, from age 65 on, stroke risk was not significantly different between the two wealth groups for men or women. 'We expected wealth to be a strong predictor of stroke in the elderly,' Dr Avendano said.
Wealth more than income 'comprehensively reflects both lifelong earnings and intergenerational transfers, and increases access to medical care and other material and psychosocial resources,' Dr Avendano added. 'We were surprised to see that it was not associated with stroke beyond age 65.'
The study also found a greater prevalence of common risk factors for stroke, including high blood pressure, smoking, inactivity, overweight, and diabetes, among the 50- to 74-year-olds with lower wealth, income and education. -- REUTERS