Heart Disease and Stroke Rates Closely Tied to National Income

An analysis of heart disease and stroke statistics collected from 192 countries by the World Health Organization shows that the relative burden of the two diseases is closely linked to national income.University of California researchers found that developing countries tend to suffer more death and disability by stroke than heart disease.  Meanwhile, the United States and other countries with higher national incomes tend to experience the opposite.

This finding may help health officials design tailored interventions to best fit the needs of developing countries, the researchers say.

“In general, heart disease is still the number one cause of death worldwide, but there is quite a lot of variation across the globe,” said Anthony  Kim, MD, MAS, assistant professor of neurology at UCSF .

For instance, there was a wide variation in the mortality rate for stroke highlighted by the new research.  Rates ranged from a worldwide low of 25 deaths per 100,000 in the island nation of Seychelles to a high of 249 deaths per 100,000 in Kyrgyzstan – a rate nearly 10 times greater.

In the United States, there are approximately 45 deaths per 100,000 people due to stroke.

Heart disease and stroke are similar in that they are both are caused by reduced or restricted blood flow to vital organs and share many of the same common risk factors, such as hypertension, diabetes, high cholesterol, obesity, physical inactivity and smoking.

However, because they affect very different tissues – the heart and the brain – they diverge in terms of symptoms, approaches to critical care, follow-up treatment and the duration and cost of recovery.

“There was a striking association with national income,” Kim said.

In the United States, for instance, heart disease is the number one killer and stroke the number four, according to the Centers for Disease Control and Prevention. This also holds true for the Middle East, most of North America, Australia and much of Western Europe.

The opposite is true in many developing countries. Stroke  is more prevalent in China, many parts of Africa, Asia and South America.

Overall, nearly 40 percent of all nations have a greater burden of stroke compared to heart disease.

“This is significant,” said Kim, “because knowing that the burden of stroke is higher in some countries focuses attention on developing a better understanding of the reasons for this pattern of disease and may help public health officials to prioritize resources appropriately.”

The study was published in the journal Circulation.