Clinical predictive factors of subthalamic stimulation in Parkinson's disease

Abstract

High-frequency stimulation of the subthalamic nucleus (STN) constitutes one of the most effective treatments for advanced forms of Parkinson's disease. The cost and potential risks of this procedure encourage the determination of clinical characteristics of patients that will have the best postoperative outcome. Forty-one Parkinson's disease patients underwent surgery for bilateral STN stimulation. The selection criteria were severe parkinsonian motor disability, clear response of symptoms to levodopa, occurrence of disabling levodopa-related motor complications and the absence of dementia and significant abnormalities on brain MRI. Clinical evaluation was performed 1 month before and 6 months after surgery. The improvement in the activities of daily living subscale of the Unified Parkinson's Disease Rating Scale, Part II (UPDRS II) and parkinsonian motor disability (UPDRS III) was greater when the preoperative scores for activities of daily living and parkinsonian motor disability, in particular axial symptoms, such as gait disorders and postural instability assessed at the time of maximal clinical improvement (on drug), were lower. Age and disease duration were not predictive, but parkinsonian motor disability tended to be more improved in patients with younger age and shorter disease duration. The severity of levodopa-related motor complications was not a predictive factor. The outcome of STN stimulation was excellent in levodopa-responsive forms of Parkinson's disease, i.e. in patients with selective brain dopaminergic lesions, and moderate in patients with axial motor symptoms and cognitive impairment known to be less responsive or unresponsive to levodopa treatment, i.e. when brain non-dopaminergic lesions develop in addition to the degeneration of the nigrostriatal dopaminergic system. The results are consistent with the classical inclusion criteria for STN stimulation, but imply that the decision to operate on the oldest patients and/or patients with gait and postural disorders, who are poorly responsive to levodopa, should be weighed carefully.

Deep Brain Stimulation for Parkinson's Disease

“…H. Abboud et al report on a retrospective review of pre-and postoperative data in 130 patients, suggesting that postural instability and worse pre-DBS motor score are the strongest predictors of poorer functional and QOL outcomes, while age at surgery and duration of the disease did not seem to in uence the outcome. On the other hand, the presence of tremors and the absence of dyskinesia and of freezing of gait are reported as the greatest predictors of global improvement, con rming prior reports [7,8]. is study is also the rst to report preoperative high BMI as a potential predictor of poorer functional outcome.…”

High-Frequency Stimulation of the Subthalamic Nucleus Suppresses Oscillatory Activity in Patients with Parkinson's Disease in Parallel with Improvement in Motor Performance

“…Likewise, cortical ␤ activity is suppressed during HFS of the STN, with the change correlating with clinical improvement (Silberstein et al, 2005). Levodopa treatment also reduces LFP oscillations in the ␤ band in parallel with clinical improvement of motor symptoms (Brown et al, 2001;Priori et al, 2004;Kü hn et al, 2006), and a common mechanism of action through ␤ suppression might explain why levodopa and HFS correlate in the clinical efficacy achieved (Charles et al, 2002;Welter et al, 2002), but do not have major additive effects (Nutt et al, 2001).…”

STN‐stimulation in Parkinson's disease restores striatal inhibition of thalamocortical projection

“…Parkinson's disease with medically intractable motor complications [Deep-Brain Stimulation Group, 2001, Ostergaard et al, 2002Limousin et al, 1998] but no dementia or psychiatric complaints [Welter et al, 2002]. Yet, the exact mechanism underlying the effect remains unclear.…”