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Controlling Parkinson's Disease With Adaptive Deep Brain Stimulation
Published on: July 16, 2014
Neuropsychological changes 1-year after subthalamic DBS in PD patients: A prospective controlled study
Lorys Castelli1, Laura Rizzi, Maurizio Zibetti
1Department of Neuroscience, University of Turin, via Cherasco 15, 10126 Turin, Italy. castelli_lorys@hotmail.com
Objective:
This study aimed at investigating the neuropsychological effect of DBS of the Subthalamic Nucleus in patients with advanced Parkinson's disease (PD).
Methods:
A standardized neuropsychological test battery, assessing reasoning, memory and executive functions, was administered to 27 PD patients who underwent DBS-STN (DBS group) and to a matched control group of 31 PD patients under optimal medical treatment (MED group). Patients were evaluated at baseline and at the end of 1 year.
Results:
Change score analysis (T1 minus T0 scores) demonstrated a significant decline in phonemic verbal fluency in the DBS group compared with the MED group (p < 0.005), while there were no significant changes between the two groups for the other cognitive tests. Single cases analysis by means of multivariate normative comparisons revealed that 4 out of 27 DBS patients (15%) showed cognitive deterioration one year post surgery. These patients were significantly more compromised from a motor standpoint (UPDRS, section III) than the 23 DBS PD patients who had no cognitive decline post surgery.
Conclusion:
Results of this prospective controlled-study showed that phonemic verbal fluency declined one year after DBS-STN, while the other cognitive domains did not change significantly. Nevertheless, single case analysis highlighted the fact that a subgroup comprising 15% of DBS-STN patients (4/27) showed significant cognitive decline 1 year after surgery.
