May 23, 2026

@michaelokun

Could some cases of essential tremor actually carry hidden Parkinson’s biology or are these false positives? Spoiler alert: The rate of 37% in this study should give us all pause to think about what this means. Alpha-synuclein is a sticky protein linked to Parkinson’s disease and related disorders. When abnormal forms build up in nerves or the brain, it may signal an underlying synucleinopathy years before classic symptoms emerge. Nora Vanegas Arroyave and colleagues describe in a new paper in Neurology Open Access how skin biopsies from folks w/ essential tremor revealed unexpectedly frequent deposits of phosphorylated alpha-synuclein. Key points: – About 37% of folks w/ essential tremor in the study had positive phosphorylated alpha-synuclein skin biopsies, compared to about 3% in healthy controls. – Participants w/ essential tremor also had higher rates of REM sleep behavior disorder, smell loss and abnormal DaTscans, all features linked to Parkinson’s disease risk. – More severe tremor scores were associated w/ a higher likelihood of a positive skin biopsy. My take: This paper is thought provoking and may shift the way you and I see essential tremor. Essential tremor has traditionally been viewed as separate from Parkinson’s disease, however these findings raise the possibility that in some folks there may be overlapping biology years before classic Parkinson’s symptoms emerge. A positive skin biopsy does not mean someone has Parkinson’s disease today, and we should avoid over-interpreting early biomarker data. However, this study may point us toward identifying which individuals w/ essential tremor could be at higher future risk for developing a synuclein disorder. Also is it possible the presence of essential tremor is a risk for a false positive skin biopsy? Points that resonated w/ me: - Essential tremor may not be a single disorder and there may be biologically distinct subtypes hiding under one label. - Skin biopsy biomarkers are moving neurology closer to detecting disease biology before classic symptoms fully emerge, however we need to consider disorders that may introduce a higher risk for false positives. #parkinson #tremor