Chronic dizziness may have several common causes, including anxiety disorders, migraine, traumatic brain injury and disorders in the part of the nervous system governing involuntary activities, according to a report in the February issue of Archives of Otolaryngology - Head & Neck Surgery.
One particular type of chronic dizziness not related to vertigo (a feeling of turning or whirling usually associated with inner ear problems) has long vexed physicians, according to background information in the article. "Patients with this syndrome have chronic nonspecific dizziness, subjective imbalance and hypersensitivity to motion stimuli, which are exacerbated in complex visual environments (e.g., walking in a busy store, driving in the rain)," the authors write. Some researchers have proposed the term chronic subjective dizziness for this condition.
Jeffrey P. Staab, M.D., M.S., and colleagues at the University of Pennsylvania Health System, Philadelphia, studied 345 men and women age 15 to 89 (average age 43.5) who had dizziness for three months or longer due to unknown causes. From 1998 to 2004, the patients were tracked from their referral to a balance center through multiple specialty examinations until they were given a diagnosis.
"All but six patients were diagnosed as having psychiatric or neurologic conditions, including primary or secondary anxiety disorders, migraine, traumatic brain injury and neurally mediated dysautonomias," or abnormal functioning of the autonomic nervous system, which controls involuntary actions. Anxiety disorders were associated with 60 percent of the chronic dizziness cases and central nervous system conditions (including migraine, brain injuries and autonomic nervous system disorders) with 38.6 percent. Six patients (1.7 percent) had irregular heartbeats.
"The results of this investigation provide some insight into pathophysiologic mechanisms that may precipitate and perpetuate chronic dizziness," the authors write. "Two-thirds of patients had medical conditions associated with the onset of dizziness, whereas one-third had anxiety disorders as the initial cause. Therefore, chronic subjective dizziness may be triggered by either neurotologic [ear-related] or psychiatric conditions."
"Key diagnostic features were identified in the clinical history for each illness," they continue. For example, those with migraines often had nausea or vomiting, anxiety disorders were associated with fear and worry, and those with autonomic nervous system disorders tended to become dizzy when they exerted themselves. "Careful inquiry about these key features during otologic evaluations may increase diagnostic precision and lead to more specific treatment recommendations for these perplexing patients."