Levodopa-Carbidopa Intestinal Gel Infusion Therapy Discontinuation: A Ten-Year Retrospective Analysis of 204 Treated Patients.

Background: Parkinson's disease (PD) is the second most common progressive neurodegenerative disease. In the advanced stages, the continuous delivery of levodopa (LD) as levodopa-carbidopa intestinal gel (LCIG) has demonstrated significant improvement of motor and nonmotor complications and improvement of the patients' quality of life (QoL). Despite the growing global experience with this treatment, anumber of unsolved practical issues remain, and currently, the data on the reasons that can lead to the discontinuation of LCIG are scarce.

Objective: In the present study, we aimed to analyze the causes that led to the discontinuation of LCIG therapy.

Methods: In this retrospective study, after 10 years of experience with LCIG as a therapeutic option in advanced PD, we analyzed the data of all dropout cases among the 204 patients that initiated LCIG therapy in two Romanian centers.

Results: Of the 204 patients enrolled, 43 patients dropped out. Disease duration until LCIG infusion was significantly longer (11.67±4.98 vs 9.44±3.44) and the overall clinical picture more sever (both regarding motor symptoms and cognitive decline) in dropout patients (compared to patients who continued treatment). The dropout patients also presented significant differences regarding the incidence of polyneuropathy (32.5% vs 11.18%). The main cause of discontinuation was death.

Conclusion: The causes of discontinuation from LCIG therapy in Romanian patients are similar to those from other centers; however, the rate of dropouts is somewhat lower. The clinician's experience in selecting and treating the patients in advanced stages of PD can increase therapeutic adherence. Also, the presence of a well-trained caregiver along with the availability of a proper aftercare system is mandatory for maintaining the long-term benefits of the therapy and the overall best outcome possible. Targeted prospective studies are needed to confirm whether a more severe stage of the disease and cognitive impairment at the time of initiation, respectively, the association of polyneuropathy can be considered as predictive factors for dropout.