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Feb. 20, 2007 ? Unexplained chronic dizzinessdizziness has long puzzled doctors, but a new study sheds light on the possible causes of the condition.
Both neurological problems, such as migraines, and psychiatric problems, such as anxiety, may play roles, and it's often not an "either/or" situation, says Jeffrey Staab, MD, a researcher for the study and the attending psychiatrist at The Balance Center at University of Pennsylvania in Philadelphia.
"In some cases, it is definitely neurologic or psychiatric," Staab says. "But more often than not, when someone has chronic dizziness, you have both a neurologic and psychiatric contribution that worsen each other in a vicious cycle."
The Problem
Staab focused on a type of chronic dizziness not related to vertigovertigo -- the feeling of whirling usually linked with inner ear problems. Among these forms of dizziness, he says, is one type that is particularly mysterious.
He focused on this type, which has been called "psychogenic dizziness" and is associated with anxiety. He prefers to call it chronic subjective dizziness.
Patients who have it feel dizzy, off-kilter, imbalanced, and are very sensitive to motion stimuli, such as crowded environments or heavy traffic, Staab tells WebMD.
"The best way to understand this form is to shake your head back and forth 20 times," he says. When you are done, that is the feeling these people feel, he notes.
When these patients enter an environment filled with visual stimuli, such as having to drive in the rain or navigate through a busy grocery store, the dizziness gets worse. "Too much sensation is coming in to the brain," Staab says of the condition, which can be disabling.
"About 3% to 5% of American adults have recurrent bouts of dizziness," Staab says. About 1% have persistent dizziness.
The Study
In his study, Staab and his co-author, Michael J. Ruckenstein, MD, also of the University of Pennsylvania, evaluated 345 men and women, aged 15 to 89, who had complained of chronic subjective dizziness for three months or longer and had sought help at The Balance Center from 1998 to 2004.
After evaluating their balance, Staab and Ruckenstein also asked about illness that can lead to dizziness, such as inner ear infections, migraine headaches, concussions, or other brain injuries.
They also screened them for psychiatric disorders, especially anxiety problems, which can cause dizziness.
Anxiety Disorders Common
Anxiety disorders were found to be linked to 60% of the chronic dizzinessdizziness cases; central nervous system conditions such as migraine and brain injuries explained more than 38% of the cases. In less than 2%, abnormal heart rhythms were identified as the cause of the dizziness.
Two-thirds of the patients had medical problems (such as an inner ear infection) that first caused the dizziness; one-third had a psychological event, typically a panic attack, which caused the dizziness initially.
But sometimes, patients with an initial problem that was medical later developed a psychiatric problem. "The medical feeds the psychiatric," Staab says.
Medical Considerations
"The idea that dizziness is either medical or psychiatric is potentially problematic because so often it is both," Staab says. "And typically when it is both, the illness began as a medical condition."
For instance, he says, a chronically dizzy patient may tell his doctor he is afraid to drive because of dizziness, and the doctor labels it as a psychiatric problem.
But the patient may have forgotten to mention that an inner ear infection initially made him dizzy and made him anxious about driving.
Patients with chronic dizziness need to be screened for headaches, brain injuries, and other problems in addition to simply anxiety, Staab says.
Another Expert Weighs In
The new study builds on previous research, says Joseph Furman, MD, PhD, a neurologist and professor of otolaryngology at the University of Pittsburgh and a veteran researcher on the topic.
"If you take a close look at people who are dizzy without a diagnosis of disease, the two main things you are going to come up with are anxiety and migraine," he says, citing his own and others' research. "But it is complicated. People with anxiety aren't immune to vestibular [inner ear] disorders."
That points to the wisdom, he says, of including both medical and psychological assessments for chronic dizziness.
The study is published in the February issue of the Archives of Otolaryngology Head and Neck Surgery.
SOURCES: Jeffrey Staab, MD, attending psychiatrist, Penn Balance Center, University of Pennsylvania, Philadelphia. Joseph Furman, MD, PhD, neurologist and professor of otolaryngology, University of Pittsburgh. Staab, J. Archives of Otolaryngology Head and Neck Surgery, February 2007; vol 133: pp 170-176.