LONDON (Reuters) - Cardiovascular disease remains the leading cause of death in middle-aged adults worldwide, French newspaper Le Figaro said on Monday, citing two studies published on Tuesday.

`` Cancer is likely to become the most common cause of death in the world in a few decades, '' according to the researchers who prepared two studies, with heart disease accounting for more than 40% of deaths, meaning about 17.7 million deaths in 2017.

The researchers, whose work was presented at the European Heart Association conference in Paris, points to the huge losses paid by poor countries to these diseases, where cancer is the second most common cause of death in the world in 2017, slightly more than a quarter of the deaths (26%).

According to the research, which is limited to 21 countries and published in the medical journal The Lancet, cancer in rich countries is killing more people than heart disease.

"The world is undergoing a new epidemiological transition. Cardiovascular diseases are no longer the leading cause of death in high-income countries," said Gil Deganis, an emeritus professor at the University of Laval in Quebec. The leading cause of death in the world over the next few decades. "

The study includes more than 160,000 adults who were followed for a decade between 2005 and 2016, in high-, middle- and low-income countries.

It found that people in poor countries may be 2.5 times more likely to die of heart disease than their counterparts in rich countries.