Objective: The purpose of the study was to determine the long-term neurocognitive outcomes of STN-DBS for PD.

Background: Cognitive disturbances is one of the most disabling non-motor symptoms in the course of PD. The prevalence of Dementia in PD was 24.5%; with 26.7% of nondemented patients with PD had mild cognitive impairment (MCI). Preoperative cognitive impairment is found to be a clinical predictor for the effects of STN-DBS in terms of postoperative motor disability. STN-DBS was relatively safe from a neurocognitive standpoint in well selected patients. The most consistent postoperative decline was in verbal fluency. The prevalent of dementia at postoperation were less consistent, most suggested a relatively low rate.

Methods: A neurocognitive battery has been included in the preoperative assessment for candidates of STN-DBS since 2008 in our hospital. We assessed global cognitive function using the validated HK-MoCA, and tests on attention/working memory, memory, confrontation naming, visuospatial organization, executive functions and mood. They were evaluated at baseline, 1-, 2-, 5-, and 8-year postoperatively. We analyzed pre- and postoperative interval changes using repeated measures ANOVA. Baseline and postoperative MCI frequencies were examined with qualitative reports. The postoperative cognitive outcomes between the MCI and non-MCI group were compared.

Results: A total of 132 patients with PD were assessed for STN-DBS (age 38-72) between 2008 and 2017 in the Prince of Wales Hospital, Hong Kong. 57 (43.8%) were operated (age 38-72), 36 (63.2%) were male. 57, 41 and 12 have been followed up for 1, 2, and 5 years, respectively. 24 (42%) met the MCI criteria at baseline. There was significant postoperative decline in verbal fluency (p=0.00) and improvement in verbal memory in terms of immediate learning (p=0.02) and delayed recall (p=0.04). These changes occurred at 1-year postoperation and the effect remained similar at 2-year. Both MCI and non-MCI group showed declined in verbal fluency, while the MCI group had significantly greater improvement in verbal memory. The frequencies of MCI increased slowly, from 24 at baseline, to 25, 27 and 30 at 1, 2, and 5 years, respectively. Two patients changed from MCI to non-MCI at 1 year follow-up, both were employed, had higher than mean HK-MoCA score and were impaired in verbal memory and attention at baseline.

Conclusions: The present study was the first report on long-term neurocognitive outcomes of STN-DBS in Hong Kong

References: 1) Welter ML, Houeto JL, Tezenas du Montcel S, Mesnage V, Bonnet AM, Pillon B, Arnulf I, Pidoux B, Dormont D, Cornu P, Agid Y. (2002). Clinical predictive factors of subthalamic stimulation in Parkinson’s disease. Brain 125, 575-583. 2) Massano J, Garrett C. (2012). Deep brain stimulation and cognitive decline in Parkinson’s disease: a clinical review. Frontiers in Neurology 3, 1-13.

« Back to 2018 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/neurocognitive-outcomes-of-stn-dbs-in-patients-with-parkinsons-disease-a-10-year-review-of-local-experiences-in-hong-kong/