The relationship between orthostatic dysregulation and the orthostatic test in dizzy patients.

The orthostatic test was administered to 134 dizzy patients (37 males and 97 females) who were identified as having orthostatic dysregulation from December 1990 through November 1994. The mean age of the male and female patients was 42.5 and 44.6 years, respectively, and the peak age decade was the 50s. Among the questionnaire items for orthostatic dysregulation, orthostatic dizziness was the most frequent major symptom and occurred in 116 of the patients (86.6%). Fatigue was the most frequent minor symptom and was found in 97 (72.4%). The incidence of positive orthostatic test results in the patients with orthostatic dysregulation (50.7%) was significantly higher (P < 0.01) than that in the control subjects (27.8%). There was also a significant difference (P < 0.01 or P < 0.05) between systolic pressure decrease during the orthostatic test procedure in the patients with orthostatic dysregulation and that in the control subjects. These results suggest that autonomic imbalance as reflected by the orthostatic dysregulation questionnaire and orthostatic test results is closely related to the occurrence of dizziness or vertigo.