Americans At Higher Risk Of Stroke

December 2009 - Research from Erasmus Medical Center in Rotterdam presented to the American Stroke Association's International Stroke Conference 2008 has found that American adults have a higher prevalence of stroke than Europeans, due in part to a higher rate of risk factors and barriers to health care in the United States. The study found that American men had a 61 per cent greater chance of having a stroke and American women had almost twice the chance compared to their European equivalents.

Author Mauricio Avendano, research fellow in public health explained:

"Most of this gap is among relatively poor Americans who were, in our data, much more likely to have a stroke than poor Europeans, whereas the gap in stroke prevalence is less marked between rich Americans and rich Europeans."

Researchers explain that "prevalence" is an estimate of the total number of cases of a disease existing in a population during a specified period. The study drew on 2004 data from the U.S. Health and Retirement Survey (HRS); the Survey of Health, Aging and Retirement in Europe (SHARE); and the English Longitudinal study of Aging (ELSA). These surveys include biennial interviews among people age 50 years and older.

Mauricio Avendano commented:

"The strength of these surveys is that the questionnaires were explicitly designed to be fully comparable across all countries, and the samples were drawn to be representative of the entire population in each country. The limitation is that we're dealing with self-reports of a doctor's diagnosis of stroke, not the diagnostic data itself."

Researchers analysed data from 13 667 people in the United States and 30 120 individuals in 11 European countries including stroke occurrence, socioeconomic status, and major risk factors such as obesity, diabetes, smoking, physical activity and alcohol consumption. The study found that overall women were about one-quarter less likely to have a stroke than men.

Mauricio Avendano said:

"Many risk factors for stroke, including blood pressure and smoking, have generally increased among women but remained stable among men. This may explain why the gap in stroke prevalence between men and women is less marked than before. In fact, in some age groups and populations such as France, women may have higher prevalence of stroke than men."

The study found that age-adjusted prevalence rates of stroke varied considerably across countries being highest in the United States and lowest in the southern Mediterranean European countries of Spain, Italy and Greece, as well as Switzerland. Researchers suggest that higher prevalence in Americans partly may be due to differences in risk factors and healthcare access.

Mauricio Avendano explained:

"Southern Mediterranean countries have a diet rich in vegetables, fruits and fish and lower in fats, which partly explains why heart disease is so much lower in these populations than in northern Europe and the United States. However, for stroke, the picture is more complicated. For instance, although Italy has relatively low stroke prevalence, former studies indicate that Italians have a similar or higher stroke incidence rate than people in other European countries or the United States. Thus, the results on prevalence may also reflect poor stroke survival in Italy, which will result in a lower prevalence of stroke."

The association between higher stroke prevalence and lower socioeconomic status as measured by wealth, income and education was stronger in the United States than in most European countries.

Mauricio Avendano commented:

"Beyond the contribution of specific risk factors, policies that differ dramatically between Europe and the United States may play a role. This includes healthcare access, which is universal in Europe but not in the United States, and the preventive orientation of some European systems aimed at tackling stroke risk factors, as opposed to the U.S. healthcare system, which focuses more on treatment and may actually be more successful in keeping stroke cases alive."

Researchers suggest that policies such as those targeting nutrition and transportation may contribute to Americans being less physically active and eating less healthily than many European counterparts.

Mauricio Avendano concluded:

"Risk factors alone do not account for the differences we found, which points to the role of broader healthcare and structural policies."

Related Articles

• Stroke Care In UK Severely Deficient
  The perception of stroke among health professionals and the public must be changed so that it is viewed as a condition requiring emergency treatment.
• Anxiety And Heart Attacks
  Longstanding anxiety significantly increases the risk of heart attack in men, even when other common risk factors are taken into account.
• Heart And Brain Health Linked
  Two recent studies have thrown new light on links between cardiovascular and brain health.