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Background: Device-aided therapies (DAT), such as continuous subcutaneous apomorphine infusion (CSAI), levodopa-carbidopa intestinal gel infusion (LCIG), and deep brain stimulation of the subthalamic nucleus (STN-DBS), have markedly changed the treatment landscape of advanced Parkinson’s disease (aPD). In some patients, it is necessary to switch or combine DATs for various reasons. The aim of this retrospective study was to explore the frequency and reasons for switching between or combining DATs in two movement disorders centres in Slovenia and Israel. Methods: We collected and analysed demographic and clinical data from aPD patients who switched between or combined DATs. Motor and non-motor reasons, adverse events for switching/combining, and their frequency were examined, as was the effect of DAT using the Global Improvement subscale of the Clinical Global Impression Scale, Movement Disorders Society Unified Parkinson’s Disease Rating Scale part III, Mini Mental State Examination, and Parkinson’s Disease Questionnaire 39. Descriptive statistics and non-parametric tests were used to analyse the data. Results: Of 505 aPD patients treated with DATs at both centres between January 2009 and June 2021, we identified in a total of 30 patients (6%) who either switched DAT (n = 24: 7 LCIG-to-STN−DBS, 1 LCIG-to-CSAI, 5 CSAI-to STN−DBS, 8 CSAI-to-LCIG, 1 STN−DBS-to-LCIG, 1 LCIG-to-CSAI-to-STN−DBS, and 1 STN−DBS-to-CSAI-to-LCIG) or combined DATs (n = 6:5 STN−DBS+LCIG and 1 STN−DBS+CSAI-to-STN−DBS+LCIG). In most of these patients, an inadequate control of motor symptoms was the main reason for switching or combining DATs, but non-motor reasons (related to the disease and/or DAT) were also identified. Conclusions: Switching between and combining DATs is uncommon, but in some patients brings substantial clinical improvement and should be considered in those who have either inadequate symptom control on DAT treatment or have developed DAT-related complications.

A 69-year-old, right-handed man with a 27-year long history of Parkinson's disease (PD) who had been treated with levodopa (L-dopa)-carbidopa continuous intrajejunal gel infusion (LCGI) for 4 months was admitted to hospital because of worsening of dyskinesias. Dyskinesias were particularly pronounced in the oromandibular lingual region and resulted in difficulties with feeding and weight loss. He started using a straw for drinking liquids and switched to eating liquid foods. On examination during the period on medication, he had mild generalized dyskinesias and severe oromandibular dyskinesias with dystonic tongue protrusions: i.e., orolingual dystonia. Interestingly, putting a straw or a little stick into the mouth largely diminished orolingual dystonia, thus suggesting the presence of a sensory trick (Video 1). He got used to habitually putting a firm object into the mouth, both at rest and while eating, and he noticed that this was improving his swallowing. No sensory trick was present in other body regions. Muscle tone was increased axially, and he had bilateral rigidity and bradykinesia that were more pronounced on the left. There was no resting, postural, or kinetic tremor. He was bedridden due to severe postural instability and was cognitively impaired, with a score of 23 of 30 on the Mini-Mental State Examination. His remaining neurological examination was normal. The review of his medical records revealed that orolingual dystonia already had been present prior to LCGI treatment. There was a clear temporal relationship between dyskinesias and oral L-dopa, with involuntary movements consistently emerging 30 to 45 minutes after L-dopa intake as peak-dose dyskinesias.On admission, his LCGI settings were as follows: 9 mL in the morning, 3.5 mL per hour during the day for 16 hours, and a 2.5-mL bolus if needed, usually twice a day (total, 70 mL daily, corresponding to an average daily L-dopa dose of 1400 mg). In addition, he was taking Madopar (Roche Products Limited, Welwyn Garden City, UK) dispersible 100 mg/ 25 mg in the morning (1 tablet if needed), Stalevo 150 (1 tablet before going to bed; Orion Pharma [UK] Limited, Newbury, UK), pantoprazole 20 mg once daily, quetiapine 100 mg 1 tablet before bed, and fludrocortisone 0.1 mg once per day. It was consistently noted that dyskinesias were getting worse after additional boluses of LCGI (Video 1). A decrease in the daily rate of LCGI from 3.5 to 3.2 mL per hour and a decrease in the bolus dose from 2.5 to 2.0 mL were attempted (together with the morning dose of 9 mL, corresponding to an average L-dopa dose of 1280 mg daily) with noticeable reduction in the severity of dyskinesias, including orolingual dystonia, although these were still present as the patient continued to use sensory tricks to improve feeding.L-Dopa-induced dystonia in PD may be seen as an off-period, biphasic, or peak-dose phenomenon. Off-period dystonia most commonly involves the foot ipsilateral to the side more affected by PD, whereas biphasic dystonia tends to involve the lower limbs bi...

Advanced stage of Parkinson's disease is associated with motor complications: motor fluctuations and dyskinesias. The disease can no longer be satisfactorily treated with oral therapy that is based on treatment with levodopa. Dying of dopamine neurons, a short half-life of levodopa and pulsatile stimulation of dopamine receptors are the main reasons for these complications. Currently, there are three options available to treat the advanced stage of Parkinson's disease: subcutaneous infusion of apomorphine, intrajejunal infusion of levodopa and deep brain stimulation. It is necessary to choose the optimal method of treatment that is most suitable for the individual patient.