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C9orf72 expansion carriers with frontotemporal dementia had reduced parasympathetic activity

Original source

Basal parasympathetic deficits in C9orf72 hexanucleotide repeat expansion carriers relate to smaller frontoinsula and thalamus volume and lower empathy.Neuroimage Clin · 29 July 2024 (opens in a new tab)

Compass summarised this from the study's abstract.

Study details

Studied in
Human

Related topics

People with C9orf72 expansions and frontotemporal dementia had lower baseline respiratory sinus arrhythmia, a measure of parasympathetic activity, than other expansion carriers and healthy controls. Lower levels were associated with more severe behavioural symptoms, reduced empathy and smaller volumes in several brain regions.

Why this matters

The findings may help researchers study how C9orf72-related disease affects autonomic function and behaviour. They do not establish a diagnostic test, treatment benefit or change in care for people with amyotrophic lateral sclerosis (ALS), and the study did not report that respiratory sinus arrhythmia predicts ALS.

Limitations and context

This was a study of 102 participants, including 49 C9orf72 expansion carriers across different clinical groups. The results show associations rather than proving that reduced parasympathetic activity causes brain or behavioural changes. The proposed biomarker requires further validation, including in people with C9orf72-related ALS.

Summarised by Compass 17 August 2026

This summary was generated by AI from the source listed above. It is not medical advice, so read the original source for anything that affects your care.

Bibliographic data from PubMed is courtesy of the U.S. National Library of Medicine. Compass does not reproduce source abstracts and may not reflect the most current record.

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