title: Replacement of dopaminergic medication with subthalamic nucleus stimulation in Parkinson's disease: long-term observation.
abstract: Stimulation of the subthalamic nucleus (STN) is an effective treatment for advanced Parkinson's disease (PD), but the medication requirements after implant are poorly known. We performed a long-term prospective evaluation of 20 patients maintained at stable dopaminergic therapy for 5 years after bilateral STN implants, who were evaluated 6 months, 1 year, 3 years, and 5 years after surgery. We measured, during the entire observation period, the effect of deep brain stimulation on motor and functional outcome measures, the levodopa equivalent daily dose and the total electrical energy delivered. At 5 years, the UPDRS motor score had improved by 54.2% and levodopa equivalent dose was reduced by 61.9%, compared with preimplant. Dopaminergic medication remained stable during the observation period, but energy was progressively increased over time. Rest tremor, rigidity, gait, lower and upper limb akinesia, and total axial score were improved in decreasing order. Postural stability and speech improved transiently, whereas on-period freezing of gait, motor fluctuations and dyskinesias recovered durably. Functional measures did not show improvement in autonomy and daily living activities after STN implant. Chronic STN stimulation allows to replace for dopaminergic medications in the long-term at the expense of an increase of the total energy delivered. This is associated with marked improvement of motor features without a matching benefit in functional measures.
authors.affiliation: Fondazione IRCCS Istituto Neurologico, Carlo Besta, Milano I-20133, Italy.
authors.forename: Luigi M
authors.initials: LM
authors.lastname: Romito
authors.forename: Maria Fiorella
authors.initials: MF
authors.lastname: Contarino
authors.forename: Nicola
authors.initials: N
authors.lastname: Vanacore
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Bentivoglio
authors.forename: Massimo
authors.initials: M
authors.lastname: Scerrati
authors.forename: Alberto
authors.initials: A
authors.lastname: Albanese
mesh_terms: D046690:Deep Brain Stimulation / Q000379:methods*; D004185:Disability Evaluation; D015259:Dopamine Agents / Q000627:therapeutic use; D004567:Electrodes, Implanted; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D010300:Parkinson Disease / Q000503:physiopathology / Q000628:therapy*; D012720:Severity of Illness Index; D020531:Subthalamic Nucleus / Q000502:physiology*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015259:Dopamine Agents; D007980:Levodopa