Smoking, Affluent Lifestyle Boost Mortality Statistics
Infectious and parasitic diseases are the leading cause of mortality on the planet, but heart disease, stroke and cancer - disorders associated with longevity, smoking and an affluent lifestyle - now kill almost as many people worldwide, according to a new report by the World Health Organization.
Infections accounted for nearly one-third of the 51 million deaths in 1993. Pneumonia and other respiratory infections alone kill about 4.1 million children under the age of 5, and the many causes of diarrhea claim another 3 million. The most devastating individual infections, tuberculosis and malaria, kill 2.7 million and 2 million people, respectively, each year, according to the study.
Infection probably always has been the likeliest cause of death for human beings, although today, more than 90 percent of the risk of dying from this cause falls on people in poor and developing nations. The WHO report, however, sketches a picture in which wealth, longevity and modernity bring their own toll of illness.
Diseases of the circulatory system accounted for 9.7 million deaths in 1993, or 19 percent of the total. About 4.3 million of those were from “ischemic heart disease,” whose main forms, heart attack and congestive heart failure, are most common in people who consume high-fat diets, smoke and are physically inactive. Stroke, which to a lesser extent is a marker of an affluent lifestyle, killed 3.9 million people.
Cancer was the third major cause of mortality, responsible for 12 percent of deaths. The risk of cancer rises as life lengthens. Since 1980, life expectancy has increased worldwide by four years and now stands at roughly 65 years of age.
WHO epidemiologists detected a slight decrease in lung cancer from 1990 to 1993, which they think reflects a decline in smoking in the industrialized world. An increase in smoking in developing nations, however, virtually guarantees more cases of lung cancer in decades to come.
“Smoking is emerging as the world’s largest single preventable cause of illness and death,” the report’s authors wrote. They estimated there are 1.1 billion smokers in the world, about 800 million in developing countries. The world’s population is roughly 5.6 billion.
“Smoking already kills an average of 3 million adults a year worldwide. If current trends continue, this figure is expected to reach 10 million by the year 2020,” they wrote.
A growing cause of ill health and medical expense, if not directly of death, is diabetes. The report predicted that 100 million will have the disease by the end of the century. Nearly 90 percent will be cases of adult-onset diabetes, which commonly is brought on by obesity and a high-calorie diet in people with a genetic predisposition for the condition. In India, 25 percent of the population has diabetes by age 60, and in North America, 20 percent of people develop it by age 70, the epidemiologists wrote.
Although WHO, which is based in Geneva, has made previous efforts to compile death and disease statistics for the entire globe, the recent effort is thought to be more accurate than earlier ones.
The report was drawn from individual countries’ data.