We're living longer, but getting more sick, study finds
Global study reveals lifespans have grown by more than a decade since 1970, but many spend much of that time fighting cancer or heart disease
People live more than a decade longer on average than they did in 1970, but spend many of these years battling diseases such as cancer, according to a global health review.
By 2010, a man's life expectancy at birth had risen 11 years from 1970 and that of a woman 12 years, said studies published by The Lancet medical journal.
But as we live longer, more years are marred by illness, with non-infectious maladies such as cancer and heart disease claiming ever more victims.
"Over the last 20 years, globally, we've added about five years to life expectancy, but only about four years to healthy life expectancy," said Josh Salomon, of the Harvard School of Public Health.
"You can think about it as adding the equivalent of four years of good health and one year of bad health."
Contributors to the study appealed for a shift in health policy focus from simply keeping people alive to keeping them healthy.
"Health is about more than avoiding death," said Alan Lopez and Theo Vos, of the University of Queensland's School of Population Health.
The review is the work of nearly 500 authors from 50 countries, with data from academic research papers, autopsy reports, hospital records and censuses, covering 291 types of disease and injury in 187 countries.
With the exception of subSaharan Africa, it shows a clear shift in the disease burden from malnutrition, infectious diseases and birth complications, that generally kill younger people, to cancer, heart disease and diabetes that can linger for years.
The growing burden of disability "implies additional health care needs and costs in terms of social costs, financial costs and the demands on the health care delivery system," Salomon said.
The study said non-communicable diseases like cancer, diabetes and heart disease accounted for nearly two-thirds of deaths in 2010 - up from half in 1990. The number of people dying from cancer rose by 38 per cent in the same period - eight million compared to 5.8 million.
The number of deaths from malnutrition and infectious, maternal and neonatal diseases fell from 15.9 million in 1990 to 13.2 million in 2010.
"The big issue here is the transformation from risks really related to poverty at the global level to risks that are more profoundly related to a series of non-communicable diseases and the way people live their lives," said study leader Christopher Murray, of the University of Washington.
In 2010, high blood pressure (9.4 million deaths) and tobacco smoking (6.3 million deaths) posed the biggest risks to health worldwide, followed by alcohol (five million deaths).
An unhealthy diet and physical inactivity were collectively responsible for an estimated 12.5 million deaths.
The study noted a sharp rise in chronic disability from causes like mental disorders, substance abuse, diabetes and muscular-skeletal ailments.
"These diseases that cause chronic disability tend to be related to age, so as populations get older and premature mortality rates go down, you have more people living into the age groups where these are quite common," said Murray.
"This is one of the broader transformations we see globally, particularly outside of sub-Saharan Africa."
In that part of the world, life expectancy of men fell by 1.3 years over the four decades from 1970 and that of women by 0.9 years, mainly due to HIV/Aids.
Japanese women had the world's highest life expectancy at 85.9 years, followed by Icelandic men at 80 years.
The impoverished island of Haiti had the lowest life expectancy (32.5 years for men and 43.6 for women), mainly due to the 2010 earthquake that killed at least 250,000 people.