Tai Chi for Reducing Dual-task Gait Variability, a Potential Mediator of Fall Risk in Parkinson's Disease: A Pilot Randomized Controlled Trial.

OBJECTIVES: To assess the feasibility and inform design features of a fully powered randomized controlled trial (RCT) evaluating the effects of Tai Chi (TC) in Parkinson's disease (PD) and to select outcomes most responsive to TC assessed during off-medication states. DESIGN: Two-arm, wait-list controlled RCT. SETTINGS: Tertiary care hospital. SUBJECTS: Thirty-two subjects aged 40-75 diagnosed with idiopathic PD within 10 years. INTERVENTIONS: Six-month TC intervention added to usual care (UC) versus UC alone. OUTCOME MEASURES: Primary outcomes were feasibility-related (recruitment rate, adherence, and compliance). Change in dual-task (DT) gait stride-time variability (STV) from baseline to 6 months was defined, a priori, as the clinical outcome measure of primary interest. Other outcomes included: PD motor symptom progression (Unified Parkinson's Disease Rating Scale [UPDRS]), PD-related quality of life (PDQ-39), executive function (Trail Making Test), balance confidence (Activity-Specific Balance Confidence Scale, ABC), and Timed Up and Go test (TUG). All clinical assessments were made in the off-state for PD medications. RESULTS: Thirty-two subjects were enrolled into 3 sequential cohorts over 417 days at an average rate of 0.08 subjects per day. Seventy-five percent (12/16) in the TC group vs 94% (15/16) in the UC group completed the primary 6-month follow-up assessment. Mean TC exposure hours overall: 52. No AEs occurred during or as a direct result of TC exercise. Statistically nonsignificant improvements were observed in the TC group at 6 months in DT gait STV (TC [20.1%] vs UC [-0.1%] group [effect size 0.49; P = .47]), ABC, TUG, and PDQ-39. UPDRS progression was modest and very similar in TC and UC groups. CONCLUSIONS: Conducting an RCT of TC for PD is feasible, though measures to improve recruitment and adherence rates are needed. DT gait STV is a sensitive and logical outcome for evaluating the combined cognitive-motor effects of TC in PD.

Progression of Parkinson's disease following thalamic deep brain stimulation for tremor.

We assessed the long-term effect of thalamic deep brain stimulation (DBS) on motor symptoms and progression of Parkinson's disease (PD) in PD patients treated for resting and postural/action tremor. Thalamic DBS was performed in 17 patients with treatment-resistant resting and postural/action tremor. Nine patients were available for follow-up examination a mean of 5.5 years after surgery. Three had tremor-dominant PD. DBS produced marked improvement in resting and postural/action tremor in target upper extremity in all 9 patients, which persisted unchanged at the time of the last follow-up visit 5.5 years after surgery. PD severity with DBS 'on' and 'off' 1 year after surgery was compared to PD severity at the last follow-up visit using UPDRS (Unified Parkinson's Disease Rating Scale) III motor scores and individual motor item subscores. Patients were tested while on medication. There was no significant worsening of tremor, rigidity, speech, postural stability, gait, or axial bradykinesia with DBS either on or off at the last follow-up visit compared to the 12-month visit. UPDRS III motor scores were unchanged. However, global assessment of PD progression and increased mean L-dopa dose and L-dopa equivalent daily dose at the time of last follow-up visit indicated that a progression of PD had occurred.

Adverse effects of subthalamic nucleus DBS in a patient with multiple system atrophy.

A 59-year-old woman with levodopa-responsive parkinsonism complicated by motor fluctuations and generalized levodopa dyskinesia underwent bilateral subthalamic deep brain stimulation (STN DBS) 7 years after symptom onset. DBS improved levodopa-responsive upper extremity bradykinesia but aggravated speech, swallowing, and gait. Motor fluctuations were not improved and levodopa dose remained unchanged. Pulse generators were turned off. Clinical features and brain MRI in this case were indicative of multiple system atrophy (MSA). STN DBS is not recommended for patients with MSA.