"Traditionally, we focus suicide prevention on adolescents and the older retired population, but the results of this study really emphasized the public health burden faced by the middle aged population," said Dr. Thomas Simon, a researcher with the CDC's Injury Center.
"There are unique risks at each developmental stage," said Simon, pointing to bullying and confusion about sexuality in teenagers and getting used to retirement for seniors. "And then there are some particularly salient challenges for the middle-aged group: divorce, job loss, and dual care-giving."
The increase in the U.S. over the past two decades may also reflect the influence of the weak economy - suicides generally rise during downturns - and an increase in the use of prescription opioid painkiller drugs, the CDC said.
The U.S. economy twice went into recession during the study period, briefly in 2001 and sharply during the so-called Great Recession of December 2007-June 2009 that sent the unemployment rate as high as 10 percent.