Personality and Quality of Life Amelioration After Continuous Subcutaneous Apomorphine Infusion in Parkinson's Disease

As Parkinson's disease (PD) progresses, the onset of motor and non-motor fluctuations alters patients Quality of Life (QoL). Second-line treatments can then be proposed: either the implantation of deep brain electrodes (Deep Brain Stimulation of the Sub-Thalamic Nuclei (DBS-STN)), or the drug approach (continuous subcutaneous infusion of apomorphine or continuous intrajejunal infusion of levodopa/carbidopa).

To date, no randomized double-blind trial has compared the efficacy and adverse effects of these different types of second-line treatments. There is therefore no clearly defined predictive factor that could predict better efficacy of these second-line treatments in patients, or the occurrence of adverse effects leading to discontinuation of these treatments.

The choice of treatment must consider patients specific personal needs as well as their clinical phenotype, this constitutes the major challenge of personalized medicine. Thus, personality, which reflects the way a person thinks, reflects, acts and behaves in different situations, appears to be a possible predictive criterion for QoL improvement after second-line treatments.

Indeed, using the Temperament and Character Inventory (TCI) self-questionnaire, the investigators have shown that two personality dimensions of the TCI ("Novelty Seeking" and "Cooperativeness") appeared to be predictive of QoL amelioration in PD patients after DBS-STN. Thus, the use of this personality questionnaire, the TCI, enables better prediction of patients therapeutic response after DBS-STN. It could also be useful to predict therapeutic response after other second-line treatments such as continuous subcutaneous infusion of apomorphine. In this study, the investigators therefore propose to evaluate the impact of personality dimensions on therapeutic response after the introduction of this infusion therapy.

Investigators carried out a preliminary exploratory study (PSYCHO-PERF study - ClinicalTrials.gov NCT03793491) which showed a significant association between a personality dimension of the TCI ("Reward Dependence") and QoL improvement after six months of continuous subcutaneous infusion of apomorphine in 33 PD patients (article in preparation). This suggests that patients with high Reward Dependence scores may be good candidates for continuous subcutaneous infusion of apomorphine. However, these results need to be confirmed on a larger scale, by means of a multicenter study.

Hence, some TCI personality dimensions in PD patients could be predictive of QoL improvement after second-line treatment. Thus, before proposing a second-line treatment, in the context of personalized medicine, personality assessment could be one of the criteria to choose between these different treatments.