The Progression of Essential Tremors: Illustrative Videos

Abstract

Background: Essential tremor (ET) is a progressive neurological disease whose natural history is one of progressive increase in tremor severity over time; surprisingly though, there are no published videotape diaries that visually and tangibly portray this progression over time. Phenomenology: Progressive, stepwise increase in limb tremor severity over a ten-tofifteen-year period in three patients with ET. Educational value: We hope that this brief visual diary will serve as a useful teaching tool for students, primary care physicians, and neurologists to "see with their own eyes" the extent of change that can occur in the ETs.

Longitudinal Progression of Essential Tremor: Do Tremor Severity Scores Increase at a Uniform Rate?

“…This suggests that for a substantial number of patients, tremor does not increase uniformly over time. In fact, the irregular progressions witnessed in the previously described video compilation of three ET cases may illustrate the experiences of many ET patients ( 5 ). From a clinical standpoint, it is important for patients to realize that their tremor severity scores do not necessarily change in a uniform, steady, and regular manner over time.…”

“…For example, we compiled videos of three ET patients performing a series of movement tasks at subsequent observation points. Analyses of these videos suggest that the progression of tremor ratings in ET, at least for some patients, is best described as non-uniform, or irregular ( 5 ) (e.g., years of mild tremor followed by a sudden, pronounced increase in tremor severity). In the current analysis, we documented the occurrence of such intra-individual differences in tremor severity scores in the ET patient population, and subsequently identified different patterns of within-patient change across time.…”