ATLANTA — For the first time in almost half a century, homicide has fallen off the list of the nation's top 15 causes of death, bumped by a lung illness that often develops in elderly people who have choked on their food.
The 2010 list, released by the government Wednesday, reflects at least two major trends: Murders are down, and deaths from certain diseases are on the rise as the population ages, health authorities said.
Homicide was overtaken at No. 15 by pneumonitis, seen mainly in people 75 and older. It happens when food or vomit goes down the windpipe and causes deadly damage to the lungs.
This is the first time since 1965 that homicide failed to make the list, according to the Centers for Disease Control and Prevention.
The CDC's latest annual report on deaths contained several nuggets of good news:
The infant mortality rate dropped to an all-time low of 6.14 deaths per 1,000 births in 2010. It was 6.39 the year before.
U.S. life expectancy for a child born in 2010 was about 78 years and 8 months, up about a little more than one month from life expectancy for 2009.
Heart disease and cancer remain the top killers, accounting for nearly half the nation's more than 2.4 million deaths in 2010. But the death rates from them continued to decline.
Death rates for five other leading causes of death also dropped in 2010, including stroke, chronic lower respiratory diseases, accidents, flu/pneumonia and blood infections.
But death rates increased for Alzheimer's disease, which is the nation's sixth-leading killer, kidney disease (No. 8), chronic liver disease and cirrhosis (No. 12), Parkinson's disease (No. 14) and pneumonitis.
The report is drawn from a review of at least 98 percent of the death certificates filed in the U.S. in 2010.
The government has been keeping a list of the top causes of death since 1949. Homicide has historically ranked fairly low. It was as high as 10th in 1989 and in 1991 through 1993, when the nation saw a surge in youth homicides related to the crack epidemic.
In the past decade, homicide's highest ranking was 13th. That was in 2001 and was due in part to the 9/11 attacks.
Murders have been declining nationally since 2006, according to FBI statistics. Falling homicide rates have been celebrated in several major cities, including New York City, Detroit and Washington.
Criminologists have debated the reasons but believe several factors may be at work. Among them: Abusive relationships don't end in murder as often as they once did, thanks to increased incarcerations and better, earlier support for victims.
"We've taken the home out of homicide," said James Alan Fox, a Northeastern University criminologist who studies murder data.
Some also credit better police work and public health programs aimed at reducing violence.
Demographics are an important factor, too, as the largest segment of the population is now 50 and older. Younger people — who are most likely to commit or fall victim to murder — are making up a smaller share of the population.
That ties in to the changes in the CDC's list of causes of death.
"The risk of homicide declines with age, and the risk of death by disease increases," Fox said.
However, some causes of death associated with old age are giving way to others, noted Robert Anderson, the CDC official who oversaw the report. Doctors have been getting better at preventing and treating heart disease and cancer, which allows something else to become the cause of death.
"In previous years, someone with both heart disease and Parkinson's would have been more likely to have died from heart disease. Now with better treatment, they die from Parkinson's instead," Anderson said in an email.
Pneumonitis is another example. Despite its name, pneumonitis is not related to pneumonia. It occurs in people who have lost the ability to swallow or protect their airway.