FRIDAY, Sept. 16 (HealthDay News) -- Heart disease. Cancer. Lung disease. Diabetes.

All these scourges loom large as global killers and, unlike infectious illnesses, all are largely preventable, experts say.

But the truth is that these "non-communicable diseases" (NCDs) are now the leading cause of death worldwide by a wide margin. That's why health experts and leaders from 193 nations plan to meet next week at the United Nations in New York City to discuss strategies to lower the death toll.

"This will be the first time that the U.N. has actually focused on the major killer of most people," said Dr. Otis Brawley, chief medical officer for the American Cancer Society, and a professor of oncology and epidemiology at Emory University in Atlanta.

"We need this," he added. "We need a chronic disease movement. We need to drive attention toward overall health. Because cancer, for example, kills more people in the world than HIV/AIDS, malaria and tuberculosis combined."

As analyzed in a new report issued this week by the World Health Organization (WHO), non-infectious diseases are responsible for roughly 36 million fatalities worldwide every year. The loss in terms of life-years and productivity is staggering, since about 9 million of these deaths occur among men and women under the age of 60.

According to Dr. Gordon Tomaselli, president of the American Heart Association, "if current trends continue, well before the middle of this century [non-communicable diseases] will be responsible for more than three-quarters of the deaths around the world."

Heart disease currently accounts for the lion's share of these deaths, with WHO saying that 48 percent of non-communicable disease fatalities are attributable to cardiac illness. A little more than one in five non-communicable disease deaths are due to cancer, while respiratory illness is linked to slightly more than one in 10 fatalities. These are followed by diabetes, which claims the lives of 3 percent of non-communicable disease patients.

Poorer countries are often hardest hit by such diseases, the report noted, and by some measures their citizens bear a three times greater risk for dying from a non-communicable disease before the age of 60, compared with residents of richer nations.

"And the impact of the growing prevalence of non-communicable diseases is not only on the medical health, but the economic health of all nations, in direct care costs and that of lost productivity," Tomaselli said

Experts note that this health trend is occurring not only in poorer nations but also in the developed world, which has hardly proven immune to the ravages of non-communicable diseases.

The WHO report found, for example, that non-communicable diseases account for 87 percent of all deaths in the United States. Not coincidentally, the United States is increasingly weighted down by an obesity epidemic, a largely inactive population (with a 43 percent sedentary rate), a 16 percent smoking rate, and markedly rising blood pressure and glucose levels.

Solving problems like that are the U.N. summit's principle goal: to identify those steps that countries can take to promote healthful behaviors, blunting the impact of non-communicable diseases.

"This summit is a once-in-a-generation opportunity," the American Diabetes Association (ADA) said in a statement.

In fact, it's only the second time the U.N. has taken up a health issue -- the first, in 2001, created the Global Fund to Fight AIDS, Tuberculosis and Malaria.

The ADA noted that non-communicable diseases share many preventable risk factors, such as poor diet, insufficient exercise habits, smoking and alcohol abuse.

The ADA said those attending the upcoming summit will be shooting to achieve an ambitious but tangible goal: to curtail unhealthful behaviors and shave 25 percent off the global death rate from non-communicable diseases by 2025.

But Brawley emphasized that the U.N. effort to reach such goals will aim to build on existing public health initiatives, rather than usurp them.

"This is not a disease Olympics," he said. "And we are not in a competition. So the summit's aim is to focus the world on overall health. Not to the exclusion of infectious disease, but with the inclusion of non-infectious disease."

More information

For more on non-communicable diseases, visit the World Health Organization.