Background
and Objectives: Orthostatic dizziness (OD) is defined as when
dizziness is provoked by standing up from a supine or sitting position. It is usually
considered as being associated with orthostatic hypotension (OH). On the other
hand, it is recently suggested that otolith organ dysfunction and impaired
vestibulosympathetic reflex may account for development of OH and OD.
Vestibular evoked myogenic potential (VEMP) and subjective visual vertical and
horizontal tests (SVV/SVH) are tools for detecting otolith organ dysfunction. We
assessed cervical VEMP (cVEMP) and SVV/SVH test results in the patients with
OD to evaluate the relationship between OD and otolith organ function. Materials
and Methods: Three hundred-eighty-seven patients who visited dizziness clinic
were enrolled in this study. Seventy-three patients presented with OD (i.e., group
O), while 314 patients did not present OD (i.e., group N). Vestibular function
tests including cVEMP and SVV/SVH were performed. Results: cVEMP showed
abnormal response in 47.9% of group O and 60.2% of group N. Abnormal SVV
was found in 35.6% of group O and 31.5% of group N. Abnormal SVH was
highly found in both group O and group N (30.1%, 27.1%). Conclusion: The
values of SVV/SVH and cVEMP abnormality from both groups were not
significantly different between the groups O and N. This finding suggests that
otolithic function may not be related with OD.