Neuropsychological and psychiatric assessments following bilateral deep brain stimulation of the sub-thalamic nucleus in Japanese patients with Parkinson’s disease

The physical benefits of subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson’s disease(PD) patients are well documented, but the mental benefits are uncertain, particularly in Japanese patients. This study evaluated the clinical and neuropsychological characteristics before and after STN-DBS surgery in Japanese PD patients. PD patients (n=13, age 67.0 ± 7.8 years) were evaluated pre-surgery (baseline) and at one and six months post-surgery by two trained psychiatrists. The motor symptoms were assessed by the Unified Parkinson’s Disease Rating Scale (UPDRS) motor score. The neuropsychological and psychiatric tests performed were the Mini-Mental State Examination, the Wisconsin Card Sorting Test (WCST), the verbal fluency test (VFT), the Hamilton Depression Rating Scale and the Hamilton Anxiety Rating Scale (HAM-A). The UPDRS motor score (p<0.001) and HAM-A score (p=0.004) showed significant improvement at one month post-surgery, but a significant decline was observed in the WCST total error (p=0.005) and the semantic VFT score (p<0.001). The phonetic VFT also showed a substantial decline (p=0.015) at one month post-surgery. At six months post-surgery, the improvement in the UPDRS motor score was maintained, and the scores on the neuropsychological and psychiatric tests had returned to baseline. Although bilateral STN-DBS did not appear to have long-term effects on neuropsychological and psychiatric outcomes, the microlesion effects associated with STN-DBS appear to increase the risk of transient cognitive and psychiatric complications. These complications should be monitored by careful observation of neurological and psychiatric symptoms.

内容要旨・審査要旨・論文本文の公開:
内容要旨・審査要旨 : LID201405131002.pdf
論文本文 : LID201501221002.pdf
本論文は, 著者Michitaka Aonoの学位論文として提出され, 学位審査・授与の対象となっている。