Acute Dementia After Deep Brain Stimulation in Parkinson Disease

Background It is not clear whether cognitive adverse events can occur after subthalamic nuclei deep brain stimulation in Parkinson disease, and the putative mechanisms are poorly understood. Case Description We report on a rare case of a 68-year-old woman with Parkinson disease but no previous cognitive impairment. The day after deep brain stimulation of the subthalamic nuclei, the woman presented with new-onset dementia and acute, severe, persistent, global cognitive decline, prompting a diagnosis of Alzheimer disease. Conclusions In patients seen in routine clinical practice, the simultaneous presence of several neurodegenerative diseases might not be uncommon. The assessment of mild cognitive impairment with a standardized method is highly recommended, a systematic 3-dimensional volumetric analysis of hippocampal structures should be part of the pre−deep brain stimulation evaluation, and cerebrospinal fluid biomarkers should be screened for if at least 1 of the 2 previously mentioned aspects is abnormal.