One in three adults suffers from high blood pressure, a key trigger of heart disease, health experts said on Wednesday while underlining the growing number of cases in developing countries.
Canada and the United States have the fewest patients, at less than 20 percent of adults, but in some African countries the estimated figure is closer to 50 percent, the World Health Organization said.
Increased life expectancy and changes in lifestyle mean that chronic conditions once associated with wealthier nations are now affecting lower income countries.
"We are being successful in reducing the impact of infectious diseases and child mortality is coming down -- that means more people are surviving to advanced ages when non-communicable diseases develop," said Colin Mathers, coordinator of the WHO's mortality and burden of disease unit
"As people live longer, they are more prone to chronic diseases."
Mathers also pointed to increasing risk factors in lower-income countries such as obesity and smoking.
"As populations become better off, incomes are rising, and the calories available are increasing." he said.
"The spread of fast food, processed food, salt added in manufacturing, is all contributing to cardiovascular and cancer risks."
In many developed countries like Australia, where the incidence of heart problems peaked in the 1960s and 70s, people are diagnosed and given treatment.
But those treatments are not generally available in African countries, said Mathers.
In Niger 50.3 percent of men suffer from high blood pressure, with Malawi and Mozambique not far behind at 44.5 and 46.3 percent respectively.
The WHO World Health Statistics report published on Tuesday includes for the first time figures on raised blood pressure and raised blood glucose levels, associated with diabetes, for the first time.
One in 10 people are estimated to have diabetes, rising to up to one third in Pacific Island countries.
"This report is further evidence of the dramatic increase in the conditions that trigger heart disease and other chronic illnesses, particularly in low and middle-income countries," said WHO director general Margaret Chan.
The report also said obesity levels doubled across the world between 1980 and 2008 and half a billion people or 12 percent of the world's populations are now considered obese.
The Americas have the highest instance, at 26 percent of adults, and south-east Asia the lowest obesity levels at three percent.
The WHO said deaths in children aged under five years dropped from almost 10 million in 2000 to 7.6 million a decade later, with the decline in deaths from measles and diarrhoea-related disease "particularly striking."
The World Health Assembly, the decision-making body of the WHO, will meet in Geneva from May 21-26 where members will discuss new targets on cutting the cases of heart and lung disease, diabetes and cancer.
