Relationship Between Essential Tremor and Cerebellar Dysfunction According to Age

BACKGROUND The cerebellum and its neural circuitry have been assumed to play a major role in the pathophysiology of essential tremor (ET). In this study, we sought to find associations between ET and cerebellar dysfunction. METHODS We performed tandem gait test in 41 ET patients and 44 age-matched controls. Investigators assessed tandem gait by counting the number of missteps during ten-step tandem walk and each subject repeated the trial three times. RESULTS ET patients had a higher average and total numbers of missteps during tandem gait tests than control subjects (p<0.05). Sex-adjusted odds ratio of the association between tandem gait abnormality and ET was 3.40 (95% confidence intervals 1.06-10.85). According to age stratification, aged ET patients (age >/=70 years) showed significantly higher prevalence of tandem gait abnormality than young ones. Interaction terms determined by a likelihood ratio test was also statistically significant (p<0.05). CONCLUSIONS Dysfunction of cerebellar neural circuitry may be associated with the pathophysiological mechanism of ET. In addition, aging may be an important factor modifying the association.