PURE: CVD deaths common in poorer countries, but cancer deaths rising in richer countries
The incidence of cardiovascular disease (CVD)-related deaths is more common in low-income countries (LICs), while cancer-related deaths have increased in high-income countries (HICs) and some middle-income countries (MICs), according to new data from the PURE+ study presented at ESC 2019.
“CVD is the major cause of mortality globally. However, …. [our study showed that in the countries studied,] deaths from cancer are now more common than those from CVD, indicating a transition in the predominant causes of deaths in middle-age[d individuals],” said Dr Darryl Leong and co-authors from Population Health Research Institute, McMaster University and Hamilton Health Sciences in Hamilton, Ontario, Canada.
This prospective, population-based cohort study involved 162,534 adults (aged 35–70 years) who were recruited from 21 countries which were classified by income group ie, HICs* (n=18,073, mean age 52 years), MICs** (n=108,291, mean age 51 years), and LICs*** (n=36,170, mean age 49 years). Outcome events were documented through direct contact with the participants and administrative records. [ESC 2019, abstract 5062]
At a median follow-up of 9.5 years, 9,329 participants had CVD (ie, myocardial infarction, stroke, heart failure, and CVD death), 5,151 had cancer, 4,386 had injuries with hospital admission, 2,911 had pneumonia, and 1,830 had COPD.
When causes of death were stratified by country income level, a higher rate of CVD death was observed among individuals in LICs and MICs compared with those in HICs (43 percent and 42 percent vs 23 percent), whereas a higher rate of cancer death was noted in HICs than LICs and MICs (55 percent vs 15 percent and 30 percent). “The high CVD mortality seen in … [this] study in LICs and MICs is likely related to low access to effective healthcare,” Leong noted. “Improving access to quality healthcare is key to reducing deaths from CV and other diseases in LICs and MICs,” said Professor Salim Yusuf from Population Health Research Institute, McMaster University and Hamilton Health Sciences in Hamilton, Ontario, Canada.
“Although CVD continues to be the primary cause of death overall in adults aged 35–70 years globally, this disease is no longer the most common cause of death in HICs and several upper-MICs, where deaths from cancer are now more common than those from CVD,” the researchers said.
The age- and sex-standardized overall mortality rates were 13.3, 6.9, and 3.4 deaths per 1,000 person-years for LICs, MICs, and HICs, respectively. “This pattern of the highest mortality in LICs and the lowest in HICs was observed for all causes of death except cancer, where mortality was similar across country income levels,” Leong said.
“Whether similar patterns occur in other HICs and MICs needs to be explored, but this finding appears to indicate a new epidemiological transition among the different categories of noncommunicable diseases,” the researchers added.
“[Moreover,] if the pattern of declining CVD deaths seen in the last few decades in HICs continues and the same pattern is followed by some MICs and LICs, then it is possible that cancer will become the most common cause of death worldwide in a few decades,” Leong noted.
+PURE: Prospective Urban Rural Epidemiology study
*HICs: Canada, Saudi Arabia, Sweden, and the United Arab Emirates
**MICs: Argentina, Brazil, Chile, China, Columbia, Iran, Malaysia, Palestine, Philippines, Poland, Turkey, and South Africa
***LICs: Bangladesh, India, Pakistan, Tanzania, and Zimbabwe