The research focused on the number of deaths of centenarians — people 100 and older. Nearly 26,000 died in 2014, about a 40 percent increase over 15 years.
About 80 percent of deaths in that age group each year are women — a reflection of how many men and women live that long, said the report's author, Dr. Jiaquan Xu of the Centers for Disease Control and Prevention.
In 2014, 40 of the women were 111 or older when they died, compared to five men.
The latest census figures put the number of centenarians at 72,000. That age group accounted for about 1 percent of the 2.6 million U.S. deaths in 2014.
For the 100-plus club, heart disease is the No. 1 killer, the same as for Americans overall, followed by Alzheimer's disease.
Cancer, while No. 2 overall, is fourth for centenarians behind stroke. Death rates for cancer decline as people hit their 80s.
"It's a case of if you live to 100, you've escaped cancer and some other causes of death that are more common in younger people,"