Long-term effect of levodopa-carbidopa intestinal gel on axial signs in Parkinson's disease

Background: Few studies have suggested that levodopa-carbidopa intestinal gel (LCIG) may have a benefit on Parkinson's disease (PD) axial signs. Aims of the study: To investigate the long-term effect of LCIG on axial signs and the related prognostic factors. Methods: A retrospective study on 49 PD patients treated with LCIG. Axial signs as per the Unified Parkinson Disease Rating Scale axial score (AS), Hoehn and Yahr (H&Y) scale, and levodopa equivalent daily dose (LEDD) were assessed at baseline (before starting LCIG treatment) and at the last follow-up (FU). Results: After 47.6 ± 30 months of treatment, total AS deteriorated while motor complications still improved, in spite of a significant LEDD/Kg increment. When adjusted for LCIG treatment duration, a higher AS and freezing of gait severity at FU were predicted by a baseline lower response to l-dopa and higher H&Y (P < 0.01) and they were related to a lower independency in activity of daily life at FU (P < 0.001). Single axial items remain stable up to one year and postural instability up to four years. Conclusion: Baseline disease severity and the magnitude of l-dopa response predict axial signs' severity after around four years of LCIG treatment, with consequent implication on patients' functional independence.