Long-term course of orthostatic XXXX in serial posturographic measurement.

@entity1 @entity16 @entity400 @entity76
OBJECTIVE: Primary orthostatic @entity400 (OT) is a rare @entity16 of unknown pathophysiology characterized by a high-frequency @entity400 mainly of the legs when standing. The aim of this study was to examine its long-term course by subjective estimation and objective recording by serial posturography and to obtain further standardized epidemiological and clinical data on @entity1 with OT. METHODS: A clinical cohort of 37 @entity1 with the diagnosis of primary OT was screened for this longitudinal follow-up study. Eighteen @entity1 consented to participate. During study visit all @entity1 underwent a standardized neurological examination and completed subjective scales and scores. Posturographic recordings at follow-up were compared to prior clinical posturographic measurements in 15cases. RESULTS: In our cohort the mean duration of symptoms was 14.1      6.8 years. Subjectively, 78% of @entity1 reported progression of the disease. Posturographic data (5.4      4.0 years) revealed a significant increase of the total sway path (standing on firm ground with eyes open) from 2.4      1.3 to 3.4      1.4  m/min (p  =  0.022) and of the total root mean square values from 9.8      4.3 to 12.4      4.8  mm (p  =  0.028). None of these observations are explained by aging of the @entity1 . Mean frequency of the @entity400 did not change over time (14.7      1.9  Hz vs. 14.9      2.0  Hz at follow-up). Clinically, most @entity1 had signs of @entity76 and a substantial portion also showed proprioceptive deficits in the long-term course. CONCLUSIONS: This long-term follow-up study indicates, that primary OT is a progressive disorder. Furthermore, the clinical observation of @entity76 in most OT @entity1 in the long-term course might indicate an important role of the cerebellum in its pathophysiology.
