Impact of Disease Duration in Effectiveness of Treatment with Levodopa-Carbidopa Intestinal Gel and Factors Leading to Discontinuation.

BACKGROUND

Levodopa-carbidopa intestinal gel (LCIG) is effective in the treatment of advanced Parkinson's disease (PD). However, the patients' profile that might benefit from treatment with LCIG has not been characterized.

OBJECTIVE

This retrospective study explored the influence of disease duration (DD) on the effectiveness of LCIG and identified factors associated with treatment discontinuation in a cohort of advanced PD patients.

METHODS

Patients initiating LCIG therapy between Jan-2006 and Dec-2011 in 18 Spanish centers were included. Effectiveness in treating motor symptoms (MSs), non-motor symptoms (NMSs), and adverse events (AEs) occurrence was compared in DD≥10 or <10 years and LCIG continuation/discontinuation groups. Factors associated with LCIG discontinuation were evaluated using univariate and multivariate analyses.

RESULTS

Overall, 177 PD patients were included (52.5% male; mean age 70.6±8.4 years; mean LCIG duration 35.6±18.6 months). Patients with DD≥10 years (n = 125) experienced less reduction in "off" time (-29%) than those with DD <10 years (-38%; n = 51; p = 0.021), and reported more severe AEs (32.8% vs. 17.6%; p = 0.043). DD did not significantly influence changes in NMSs or discontinuation rates. Fifty-four patients discontinued LCIG therapy, factors associated with discontinuation were higher percentages of waking day in the "off" state (OR, 1.028; 95% CI, 1.002-1.055; p = 0.0360) and in the "on" state with troublesome dyskinesia (OR, 1.032; 95% CI, 1.002-1.064; p = 0.0376) at baseline.

CONCLUSIONS

Advanced PD patients with DD <10 years might benefit more from treatment with LCIG than patients with a longer DD. Although MSs severity at baseline was statistically associated with LCIG discontinuation, the probability was very low with little clinical significance.