Pallidal stimulation in dystonia: effects on cognition, mood, and quality of life

Abstract

Bilateral deep brain stimulation (DBS) of the globus pallidus internus (GPi) alleviates symptoms in patients with dystonia but its effects on cognition, neuropsychiatric status, and quality of life have not been examined. This is a case series report of 15 consecutive patients with different forms of dystonia who underwent bilateral implantation of DBS electrodes in the GPi. The patients were evaluated preoperatively and after 3-12 months of DBS with tests of cognition (Mattis Dementia Rating Scale, Stroop Test, Trail Making Test, Phonemic and Category Word Fluency, Digit Span, Rey Auditory Verbal Learning Test, Tonic and Phasic Alertness), neuropsychiatric status (Beck Depression and Anxiety Inventories, Montgomery Asberg Depression Rating Scale, Snaith-Hamilton Pleasure Scale, Brief Psychiatric Rating Scale), quality of life, and motor functions. GPi DBS significantly improved dystonic symptoms, functional abilities, and quality of life allowing for a significant reduction of antidystonic medications. No deterioration was observed in cognitive scores and neuropsychiatric measures. The present case series report thus provides preliminary evidence for the safety of GPi DBS regarding cognitive and neuropsychiatric functions in patients with dystonia.

Long-term neuropsychiatric outcomes after pallidal stimulation in primary and secondary dystonia

“…Another reason is that patients with major and active psychiatric issues have frequently been excluded from studies examining long-term postoperative outcomes with reported results being mostly limited to patients without major psychiatric difficulties before surgery. [13][14][15][16][17][18][19] However, 3 suicides have been reported so far within 14 months after bilateral GPi DBS. 20,21 Moreover, studies reporting neuropsychiatric outcomes in various types of dystonia (primary generalized, cervical, and secondary dystonia) and in the long-term follow-up are lacking.…”

“…The few available studies reporting on neuropsychiatric outcomes after GPi DBS have showed some improvement in mood and no major change in anxiety in primary dystonia [13][14][15][16]18,28,29 and more variable outcomes in secondary dystonia. 17,30,31 These reports have been limited by the small sample size, the relatively short follow-up (#36 months), and the lack of use of psychiatric interviews to assess patients.…”

“…15,18,28,29,32 This improvement could be secondary to the GPi DBS motor benefit, and the consequent reduction in disability and improvement of quality of life. 32 In our population, the postoperative reduction of pain could also have contributed to improve depression.…”

“…Therefore, the neuropsychiatric consequences of GPi DBS on patients with dystonia in the short and long term remain unclear, as does the influence of active psychiatric disorders on the selection of appropriate candidates for the procedure. [12][13][14][15][16][17][18][19][20][21][22] We report the long-term impact of bilateral GPi DBS on the neuropsychiatric profiles of a population of patients with primary and secondary dystonia, assessed with the Structured Clinical Interview for the DSM-IV Axis I psychiatric disorders (SCID-I). 23 METHODS Primary research question.…”

Parkinson's Disease Therapeutics: New Developments and Challenges Since the Introduction of Levodopa

“…In most patients, DBS alleviates parkinsonian motor signs, shortens 'off' periods, and reduces druginduced dyskinesias, dystonia, and motor fluctuations (Rodriguez-Oroz et al, 2004;Anderson et al, 2005;Weaver et al, 2005;Portman et al, 2006;Bronstein et al, 2011). In general, both GPi-and STN-DBS are more effective than medical management alone to alleviate motor deficits in patients with advanced PD (Just and Ostergaard, 2002;Martinez-Martin et al, 2002;Troster et al, 2003;Lezcano et al, 2004;Diamond and Jankovic, 2005;Erola et al, 2005;Halbig et al, 2005;Lyons and Pahwa, 2005;Deuschl et al, 2006;Rodrigues et al, 2007a, b;Montel and Bungener, 2009;Weaver et al, 2009b;Zahodne et al, 2009). In contrast to patients with GPi-DBS, those with STN-DBS are often able to substantially reduce the medication doses (Breit et al, 2004; …”