Levodopa-Induced Dyskinesias are Frequent and Impact Quality of Life in Parkinson's Disease: A 5-Year Follow-Up Study.

BACKGROUND:Levodopa-induced dyskinesias (LID) are frequent in Parkinson's disease (PD). OBJECTIVE:To analyze the change in the frequency of LID over time, identify LID related factors, and characterize how LID impact on patients' quality of life (QoL). PATIENTS AND METHODS:PD patients from the 5-year follow-up COPPADIS cohort were included. LID were defined as a non-zero score in the item "Time spent with dyskinesia" of the Unified Parkinson's Disease Rating Scale-part IV (UPDRS-IV). The UPDRS-IV was applied at baseline (V0) and annually for 5 years. The 39-item Parkinson's disease Questionnaire Summary Index (PQ-39SI) was used to asses QoL. RESULTS:The frequency of LID at V0 in 672 PD patients (62.4 ± 8.9 years old; 60.1% males) with a mean disease duration of 5.5 ± 4.3 years was 18.9% (127/672) and increased progressively to 42.6% (185/434) at 5-year follow-up (V5). The frequency of disabling LID, painful LID, and morning dystonia increased from 6.9%, 3.3%, and 10.6% at V0 to 17.3%, 5.5%, and 24% at V5, respectively. Significant independent factors associated with LID (P < 0.05) were a longer disease duration and time under levodopa treatment, a higher dose of levodopa, a lower weight and dose of dopamine agonist, pain severity and the presence of motor fluctuations. LID at V0 (β = 0.073; P = 0.027; R2 = 0.62) and to develop disabling LID at V5 (β = 0.088; P = 0.009; R2 = 0.73) were independently associated with a higher score on the PDQ-39SI. CONCLUSION:LID are frequent in PD patients. A higher dose of levodopa and lower weight were factors associated to LID. LID significantly impact QoL.