Deep brain stimulation for treatment of refractory Tourette syndrome: long-term follow-up

Eighteen patients with severe and refractory Tourette Syndrome underwent bilateral thalamic deep brain stimulation. The surgical procedures and stimulation processes of the cohort were reported in 2008; the 2 year follow-up was reported in 2009. The aim of the research is the assessment of long-term outcome (5-6 years) on tics, obsessional behaviours, anxiety, mood, and on the overall general health of the patients and their general satisfaction.

In this study, all 18 of the original patients will be discussed, pre- and post-DBS, according to our protocol using standardized objective schedules, as well as the clinical impressions of both clinicians and patients. As there were no substantial nor statistical differences on measures of cognitive functioning between pre-DBS and 2 year follow-up, we decided not to continue this aspect of the formal assessment, particularly as there were also no clinical indications.

At 5-6 year follow-up, there was a significant reduction in tic severity (p < 0.001), and significant improvements in obsessive compulsive behaviours (p = 0.003), anxiety (p < 0.001) and depressive (p < 0.001) symptoms. Patients, in general, required less medication for tics, co-morbid conditions and/or co-existent psychopathologies. The long-term outcome/satisfaction were not unanimous between patients and the medical team.

At long-term follow-up, DBS was very successful in terms of a significant improvement in tics and also a significant reduction in the potentially disabling symptoms of obsessionality, anxiety and depression. However, compared with our more positive overall results at 2 years, these later results demonstrate long-term difficulties as follows: non-compliance, long-term complications , and the differences in the opinions between the (a) medical, (b) the surgical teams and (c) the post-DBS patients as to their outcome/satisfaction with the procedures. Our experience highlights the need for controlled studies, for long-term follow up, and the need to improve the selection of patients for DBS.