Objective evaluation of the therapeutic responses of patients with psychological dizziness by means of static posturography

In our practice, we often encounter dizzy patients in whom organic and functional abnormalities are lacking, as assessed by a variety of clinical examinations. In these patients, anxiety and depression are strongly related to their clinical symptoms. We diagnose these patients as having "psychogenic dizziness" and treat them with antidepressants and anxiolytics. Although therapeutic evaluation of patients' subjective complaints and objective evaluation by doctors are usually performed, an objective measurement is necessary to determine whether the drug treatments are effective. In the present study, we used static posturography to objectively evaluate the therapeutic response to antidepressant and anxiolytic treatments in patients with psychogenic dizziness. Thirty-seven patients with psychogenic dizziness participated in this study. All patients were prescribed antidepressants and anxiolytics. We assessed each patient using static posturography before treatment and 4 weeks after treatment. Static posturography was performed for 60 seconds with the patients' eyes open and closed. The Clinical Global Impressions-Improvement (CGI-I) scale was used for global evaluation. On the basis of the CGI-I scores, the subjects were divided into two groups: I, improved (≦3), and N, not improved (≧4). The following static posturography measurements were used for comparison: length (LNG), environmental area (ENV), and LNG/ENV. For each of these parameters, we determined improvement rates by calculating the difference between before- and after-treatment measurements. We found that CGI-I scores correlated with LNG, ENV with eyes open, and ENV with eyes closed. The improvement rates of groups I and N were significantly different for all parameters. Data obtained from subjects that had lower improvement rates relative to control values were selected for further analysis. Control values were obtained from 2201 normal subjects. Group I subjects that had low LNG/ENV values (with eyes open) before treatment showed significantly increased LNG/ENV values (with eyes open) after treatment. Our analyses revealed statistically significant differences between groups I and N in some static posturography values obtained before and after treatment. Our findings indicate that static posturography values can be used to objectively evaluate psychogenic dizziness in future studies.