A preliminary study of transient confusional states following bilateral subthalamic stimulation for Parkinson's disease.

Transient postoperative confusion (POC) occurs in 5-25% of patients following bilateral subthalamic nucleus stimulation. We retrospectively reviewed data on 96 patients who underwent bilateral subthalamic nucleus deep brain stimulation for Parkinson's disease. Nine percent of patients developed POC. There was no significant correlation between age/perioperative factors and POC. The POC group had a significantly higher incidence of depression and frontal-subcortical dysfunction on preoperative evaluation than patients without POC. Postoperative neuropsychological evaluations revealed declines on measures of general cognitive function and memory in the POC group. We provide preliminary evidence that patients with depression and frontal-subcortical dysfunction are more likely to develop POC, and that POC is more often associated with cognitive decline following surgery. Copyright 2005 S. Karger AG, Basel.