Analysis of deep brain stimulation of the subthalamic nucleus (STN-DBS) in patients with monogenic PRKN and LRRK2 forms of Parkinson's disease

INTRODUCTION

Deep brain stimulation of the subthalamic nucleus (STN-DBS) is the most common surgical treatment for Parkinson's disease (PD). Patient selection and genetic background can modify the response to this treatment. The objective of this study was to compare both clinical and pharmacologic response of STN-DBS between patients with monogenic forms of PD and non-mutation carriers with idiopathic PD.

METHODS

A retrospective analysis among 23 carriers of genetic mutations (8 PRKN and 15 LRRK2) and 74 patients with idiopathic PD was performed. The study included comparisons of Unified Parkinson's Disease Rating Scale (UPDRS) II and III scores, Schwab and England (S&E) scale values, Hoehn & Yahr (H&Y) stage scores, and equivalent doses of levodopa before and after the surgery (at 6 and 12 months) between both groups.

RESULTS

The mean age at the time in which STN-DBS was performed was 59.5 ± 8.6. Linear mixed models showed the absence of statistically significant differences between mutation and non-mutation carriers regarding levodopa doses (p = 0.576), UPDRS II (p = 0.956) and III (p = 0.512) scores, and S&E scale scores (0.758). The only difference between the two groups was observed with respect to H&Y stage in OFF medication/ON stimulation status being lower in genetic PD at 6 months after surgery (p = 0.030).

CONCLUSION

Clinical and pharmacological benefit of bilateral STN-DBS is similar in PRKN and LRRK2 mutation carriers and patients with idiopathic PD.

Quality of life and non-motor symptoms in Parkinson's disease patients with subthreshold depression

BACKGROUND

The role of subthreshold depression (subD) in Parkinson's Disease (PD) is not clear. The present study aimed to compare the quality of life (QoL) in PD patients with subD vs patients with no depressive disorder (nonD). Factors related to subD were identified.

MATERIAL AND METHODS

PD patients and controls recruited from the COPPADIS cohort were included. SubD was defined as Judd criteria. The 39-item Parkinson's disease Questionnaire (PDQ-39) and the EUROHIS-QOL 8-item index (EUROHIS-QOL8) were used to assess QoL.

RESULTS

The frequency of depressive symptoms was higher in PD patients (n = 694) than in controls (n = 207) (p < 0.0001): major depression, 16.1% vs 7.8%; minor depression, 16.7% vs 7.3%; subD, 17.4% vs 5.8%. Both health-related QoL (PDQ-39; 18.1 ± 12.8 vs 11.6 ± 10; p < 0.0001) and global QoL (EUROHIS-QOL8; 3.7 ± 0.5 vs 4 ± 0.5; p < 0.0001) were significantly worse in subD (n = 120) than nonD (n = 348) PD patients. Non-motor Symptoms Scale (NMSS) total score was higher in subD patients (45.9 ± 32 vs 29.1 ± 25.8;p < 0.0001). Non-motor symptoms burden (NMSS;OR = 1.019;95%CI 1.011-1.028; p < 0.0001), neuropsychiatric symptoms (NPI; OR = 1.091; 95%CI 1.045-1.139; p < 0.0001), impulse control behaviors (QUIP-RS; OR = 1.035; 95%CI 1.007-1063; p = 0.013), quality of sleep (PDSS; OR = 0.991; 95%CI 0.983-0.999; p = 0.042), and fatigue (VAFS-physical; OR = 1.185; 95%CI 1.086-1.293; p < 0.0001; VAFS-mental; OR = 1.164; 95%CI 1.058-1.280; p = 0.0001) were related to subD after adjustment to age, disease duration, daily equivalent levodopa dose, motor status (UPDRS-III), and living alone.

CONCLUSIONS

SubD is a frequent problem in patients with PD and is more prevalent in these patients than in controls. QoL is worse and non-motor symptoms burden is greater in subD PD patients.

Spanish expert consensus on the use of safinamide in Parkinson's disease

Safinamide is a new add-on drug to levodopa for the treatment of Parkinson's disease (PD) with motor fluctuations. Due to the recent incorporation of safinamide into routine clinical practice, no post-authorisation phase IV studies on the safety of safinamide have been conducted to date. This study provides clinical management guidelines for safinamide based on the opinion of a group of experts in movement disorders. This project was developed in 2 phases: 16 local meetings in phase 1 and a national meeting in phase 2. The meetings followed a pre-established agenda. The present clinical practice guidelines are based on the main conclusions reached during the national meeting. The group concluded that safinamide is effective in reducing motor and non-motor fluctuations. PD patients with mild-to-moderate fluctuations benefit most from treatment, although the drug may also improve the clinical status of patients with advanced PD. The dose of other dopaminergic drugs may be reduced after introducing safinamide, which would contribute to reducing such adverse reactions as impulse control disorder. At doses higher than those usually prescribed, safinamide may also improve dyskinesia. The experts agreed that safinamide is well tolerated and causes few adverse reactions when compared with placebo.