Effects of anodal transcranial direct current stimulation on cognitive dysfunction in patients with progressive supranuclear palsy.
Progressive supranuclear palsy (PSP) is a tauopathy characterized by motor, neurobehavioral and disabling brainstem deficits. No disease-modifying therapeutic options exist. The therapeutic potential of transcranial direct current stimulation ( tDCS) has been highlighted in studies on patients with other neurodegenerative diseases. Therefore, by drawing upon the limited tDCS literature on PSP, we conducted a pilot study in order to evaluate the effect of tDCS over motor and premotor cortex in patients with PSP, with a particular emphasis on cognitive dysfunction. Eight patients affected by PSP were included (4 males and 4 females with mean age 67.4±7.4 years, range: 55-80 years and mean disease duration: 4.6±3.3 years, range: 1-11 years). The mean Unified Parkinson’s Disease Rating Scale Part III (UPDRS III) was 49±16.1 and the mean Hoehn & Yahr (H&Y) scale was 3.9±1 at baseline. All pharmacological treatments (L-dopa, pramipexole, rotigotine, rasagiline, amantadine) were maintained stable during the study. We aimed at evaluating along with the motor outcome (as it is reflected on a disease-specific rating scale), the post- tDCS cognitive status after the completion of the intervention. The clinical evaluation involved the PSP-Rating Scale, the UPDRS III and the Timed Up and Go test. Neuropsychological assessment focused on auditory-verbal memory and learning, episodic memory, visuo-motor coordination and speed of information processing, executive functions and verbal fluency (phonemic and semantic). Anodal tDCS was applied over primary motor and pre-motor cortices in 10 daily sessions. During the tDCS stimulation a constant current of 2 mA was delivered for 30 minutes. Clinical evaluations were performed at baseline, day 11, day 30 and at day 90. The PSP-Rating score (total and sections I & III) improved significantly on day 11 compared to baseline and similarly on day 30. A positive effect was also seen on action tremor. In addition to the global mental status improvement, patients showed increases in neuropsychological performance in the domains of visuo-motor co-ordination and processing speed, auditory-verbal learning, episodic memory,phonological and semantic fluency (access and retrieval from lexical memory, selective inhibition and lexical access speed). Our results suggest that tDCS has a beneficial effect on Progressive Supranuclear Palsy patients’ bulbar and motor symptoms, cognitive dysfunction, as well as daily activities, which lasts beyond the duration of the treatment.
PMID: 32283535 [PubMed – as supplied by publisher]
Psychiatriki. 2019 Oct-Dec;30(4):320-328
Authors: Alexoudi A, Patrikelis P, Deftereos S, Fasilis T, Karakalos D, Verentzioti A, Korfias S, Sakas D, Gatzonis S