MIAMI (AFP) - The suicide rate in the United States has jumped by 24 per cent in the past 15 years, including a troublesome spike among girls aged from 10 to 14, according to US government statistics out on Friday (April 22).

The rate increased by about 1 per cent a year from 1999, then accelerated to 2 per cent annually from 2006 to 2014, said the findings by the Centers for Disease Control and Prevention's National Centre for Health Statistics.

The rise was seen among both males and females and for all ages from 10 to 74, said the report.

The biggest jump was among girls aged from 10 to 14, whose suicide rate tripled from 0.5 per 100,000 people in 1999 to 1.5 per 100,000 in 2014.

A total of 150 girls in this age group killed themselves in 2014, a 200 per cent increase over 1999, the report said.

"We are seeing younger and younger kids dying by suicide," said Dr Victor Fornari, director of the division of child and adolescent psychiatry at Zucker Hillside Hospital in Glen Oaks, New York.

This is "really a worry", added Dr Fornari, who was not involved in the study.

"I think it may be a reflection of access to social media, Internet and cyber bullying, and youth are hurried. They are being exposed to things sooner than they would have been," he told AFP.

Suicide rates among boys aged from 10 to 14 were higher than in girls, but they did not experience the same spike over the course of 15 years.

In 1999, 1.9 per 100,000 people in this age group committed suicide, and by 2014 the number had risen to 2.6 per 100,000, a 37 per cent increase.

Among men, those over age 75 were most likely to kill themselves in both 1999 and 2014.

However, in contrast to other age groups, elderly men's suicide rate decreased by 8 per cent over the 15 years studied, going from 42.4 per 100,000 in 1999 to 38.8 in 2014, the report said.

The second-highest suicide rate among men was in those aged from 45 to 64, a group that saw the largest per cent increase (43 per cent) in rates, increasing from 20.8 in 1999 to 29.7 in 2014, said the study.

Among women, suicide rates were highest for those aged from 45 to 64 in both 1999 (6.0 per 100,000) and 2014 (9.8), said the report.

"This age group also had the second-largest per cent increase - 63 per cent - since 1999."

The study pointed to a narrowing of the suicide gender gap over the years, largely due to a 46 per cent increase in female suicides.

Men remain more than three times as likely as women to commit suicide.

The most common method of suicide for men was by firearm (55.4 per cent). Among women, it was poisoning (34.1 per cent).

The findings raised concern among mental health experts, who urged a new push for suicide prevention efforts.

"The vast majority of people who die by suicide have a psychiatric illness - such as depression, bipolar disorder, chemical dependency, schizophrenia," said Mr Jeffrey Borenstein, president and chief executive of the Brain and Behavior Research Foundation.

"If there was a finding about such a substantial increase in some other cause of death in the United States, this would be on the front page of all our newspapers and there would be a call to action on the part of public policy to address," added Mr Borenstein, who was not involved in the study.

"And I think we really need to see the same thing happen for the important issue of suicide prevention," he said.