Reliable cognitive change following unilateral deep brain stimulation in essential tremor

• Published in: Applied neuropsychology. Adult Vol. 31; no. 4; pp. 601 - 605
• Main Authors: Kielb, Stephanie, Speelman, Claire, Boxley, Laura, Aase, Darrin, Dawson, Erica, Changizi, Barbara, Merola, Aristide, Krishna, Vibhor, Nguyen, Christopher
• Format: Journal Article
• Language: English
• Published: United States Routledge 03.07.2024
• Subjects: Aged; Cognition - physiology; Cognitive Dysfunction - etiology; Cognitive Dysfunction - physiopathology; Cognitive Dysfunction - therapy; Deep Brain Stimulation; Essential Tremor - physiopathology; Essential Tremor - therapy; Female; Humans; Male; Middle Aged; neuropsychological assessment; Neuropsychological Tests; Reliable change index; Retrospective Studies; Ventral Thalamic Nuclei - physiology; Reliable change index; neuropsychological assessment; deep brain stimulation
• ISSN: 2327-9095; 2327-9109; 2327-9109
• DOI: 10.1080/23279095.2022.2048303

Objective: This retrospective analysis assessed regression-based reliable change (RC) of cognition in a sample of essential tremor (ET) patients who underwent unilateral deep brain stimulation of the ventral intermediate nucleus of the thalamus (VIM-DBS). Method: Thirty patients (mean age at pre-evaluation = 70.4 ± 6.3 years) underwent neuropsychological evaluation pre- and post-unilateral VIM-DBS placement (mean time between pre and post-evaluation = 13.1 ± 4.0 months). Paired samples t-tests and RC analyses were employed. Results: No significant within-group differences were observed when cognitive scores were compared between evaluations. The vast majority of patients demonstrated stability across pre-and post-surgical evaluations (i.e. 29 out of 30); however, those with high-risk co-morbid medical conditions may be vulnerable to post-surgical cognitive decline as indicated by RC measures. Conclusions: The use of regression-based RC indices to assess individual cognitive changes between pre and post-surgical evaluations control for systematic and measurement errors that can occur over repeated evaluations, and may be able to identify cognitive changes that evade detection in traditional within-group comparisons.