New research suggests four out of five teens who suffer from fibromyalgia will continue to experience pain into adulthood and about half of these cases will result in full-blown adult fibromyalgia.

"Half of the former teens we studied met the full criteria for adult fibromyalgia, and another 35 percent of them continued to have symptoms of fatigue, pain and sleep difficulty, but did not meet all the criteria for fibromyalgia syndrome," study author Susmita Kashikar-Zuck, research director in behavioral medicine and clinical psychology at Cincinnati Children's Hospital Medical Center, told WebMD.  

Fibromyalgia "muscle pain and fatigue," WebMD reported. Little is known about what causes the condition. About 80 or 90 percent of fibromyalgia patients are female.

"It appears to be caused by a pain hypersensitivity in the central nervous system," Kashikar-Zuck said. "It's sort of like the volume is turned up on pain, and now they are exquisitely sensitive to pain."

Researchers followed 94 teenagers who had suffered from fibromyalgia for six years, WebMD reported. They found 51 percent of the subjects continued to experience symptoms that "meet the American College of Rheumatology's criteria for adult fibromyalgia" by the age of about 21. Over a third did not meet the requirements, but still experienced symptoms.

When compared to healthy adults these individuals tended to experience more " higher pain, poorer physical function, greater anxiety and more visits to the doctor," WebMD reported.

"It is not surprising that the symptoms are still seen and persist into early adulthood, where major life decisions are being made," Doctor Anne Eberhard, a pediatric rheumatologist at Cohen Children's Medical Center of New Yorkm told WebMd.  

The study stresses the importance of diagnosing the condition early.

"Parents need to be careful about differentiating growing pains with fibromyalgia," Kashikar-Zuck said. "If they see a child who also has chronic muscle pain but also sleeplessness, they should seriously consider whether an evaluation should be done for fibromyalgia."