Deep brain stimulation for dementias

• Published in: Neurosurgical focus Vol. 45; no. 2; p. E8
• Main Authors: Xu, David S, Ponce, Francisco A
• Format: Journal Article
• Language: English
• Published: United States 01-08-2018
• Subjects: Alzheimer Disease - therapy; Basal Nucleus of Meynert - surgery; Deep Brain Stimulation; Dementia - therapy; Humans; Parkinson Disease - therapy; Treatment Outcome; AVLT = Auditory Verbal Learning Test; Alzheimer’s disease; PET = positron emission tomography; PDD = Parkinson’s disease dementia; cognitive decline; deep brain stimulation; ADAS-Cog 13 = Alzheimer’s Disease Assessment Scale–Cognitive subscale 13; MCI = mild cognitive impairment; CDR-SB = Clinical Dementia Rating Sum of Boxes; Ch4i = intermediate portion of the NBM; NINDS-ADRDA = National Institute of Neurological Disorders and Stroke–Alzheimer’s Disease and Related Disorders Association; dementia; DBS = deep brain stimulation; NBM = nucleus basalis of Meynert; functional neurosurgery; AD = Alzheimer’s disease; Parkinson’s disease; PD = Parkinson’s disease
• ISSN: 1092-0684; 1092-0684
• DOI: 10.3171/2018.5.focus18172

OBJECTIVE The aim of this article is to review the authors' and published experience with deep brain stimulation (DBS) therapy for the treatment of patients with Alzheimer's disease (AD) and Parkinson's disease dementia (PDD). METHODS Two targets are current topics of investigation in the treatment of AD and PDD, the fornix and the nucleus basalis of Meynert. The authors reviewed the current published clinical experience with attention to patient selection, biological rationale of therapy, anatomical targeting, and clinical results and adverse events. RESULTS A total of 7 clinical studies treating 57 AD patients and 7 PDD patients have been reported. Serious adverse events were reported in 6 (9%) patients; none resulted in death or disability. Most studies were case reports or Phase 1/2 investigations and were not designed to assess treatment efficacy. Isolated patient experiences demonstrating improved clinical response after DBS have been reported, but no significant or consistent cognitive benefits associated with DBS treatment could be identified across larger patient populations. CONCLUSIONS PDD and AD are complex clinical entities, with investigation of DBS intervention still in an early phase. Recently published studies demonstrate acceptable surgical safety. For future studies to have adequate power to detect meaningful clinical changes, further refinement is needed in patient selection, metrics of clinical response, and optimal stimulation parameters.