Twin studies recently published in The Lancet medical journal appear to show that cancer has become the leading cause of death in rich nations, displacing heart disease as the number one killer. Overall, cardiovascular disease, which includes heart failure, angina, heart attack, and stroke, was responsible for the deaths of 40 percent of all adults aged 35-70 worldwide. Cancer was in second place at 26 percent, but had a higher prevalence in high-income countries than in middle- and lower-income countries.
For the study, researchers analyzed data on diseases and death among more than 160,000 adults aged 35 to 70, in 21 high-, middle-, and low-income countries across five continents from the Prospective Urban Rural Epidemiology (PURE) from 2005 to 2016.
The countries were divided into three categories. The richest countries included Saudi Arabia, the United Arab Emirates, Sweden, and Canada. Middle-income countries included Iran, South Africa, Philippines, Colombia, China, Brazil, Malaysia, Turkey, Poland, Argentina, and Chile. Low-income countries were Tanzania, Bangladesh, India, Pakistan, and Zimbabwe. The United States was not involved in the study despite being one of the world’s wealthiest countries.
The researchers found that in high-income countries, the prevalence of cholesterol-lowering statins and blood pressure medication has brought cardiovascular disease rates down significantly. The same is not true for cancer-related deaths because there have been fewer effective therapies for preventing and treating cancer. People in poorer nations were on average 2.5 times more likely to die from heart disease than those in richer ones.
A second study looking at data from patients in the same 21 countries found that “modifiable risk factors,” including diet, behavioral and socioeconomic factors, accounted for 70 percent of heart disease cases globally. Metabolic risk factors, which includes high cholesterol, obesity or diabetes, were a main factor in more than 40 percent of all heart disease cases.