Patient's perception: shorter and more severe prodromal phase in GBA-associated PD

BACKGROUND

Prevalence and time of occurrence of prodromal symptoms of Parkinson's disease (PD) in relation to the onset of classical motor manifestation varies between patients. Possible modifying factors might be different genetic architectures predisposing to varying burden of manifestations.

OBJECTIVES

To characterize the prodromal phase in PD patients with heterozygous mutations in the GBA gene compared to PD patients without GBA mutation.

METHODS

In a retrospective design, 151 participants [47 PD patients carrying a GBA mutation (PD_GBA ), 52 idiopathic PD patients (PD_idiopathic ), 52 healthy elderly (CON)] underwent a validated structured interview designed to assess prevalence and time of occurrence of prodromal symptoms.

RESULTS

PD_GBA showed a higher prevalence of prodromal symptoms and almost simultaneous occurrence of non-motor and early motor symptoms shortly before PD diagnosis whereas PD_idiopathic reported a longer prodromal phase starting with non-motor symptoms.

CONCLUSION

The short and severe prodromal phase in PD_GBA might call for shorter assessment intervals in yet premanifest GBA mutation carriers.

Depression in Parkinson's disease

Among the recently well appreciated non-motor symptoms in Parkinson's disease (PD), depression plays a prominent role due to its frequency and impact on quality of life. However, depression may be confounded by motor symptoms, especially akinesia and other non-motor symptoms such as apathy, anxiety and dementia. Data on specific diagnostic tools or treatment for depressive symptoms in PD patients are still sparse. Here we summarize an expert opinion based on available data and clinical experience.

GBA-associated PD presents with nonmotor characteristics

OBJECTIVE

To evaluate whether there exists distinct characteristics in glucocerebrosidase (GBA)-associated Parkinson disease (PD) with regard to motor and nonmotor symptoms as well as imaging characteristics assessed by transcranial sonography (TCS).

METHODS

Twenty patients with PD with heterozygous GBA mutations (N370S, L444P) (GBA-PD) in comparison to 20 patients with sporadic PD negative for GBA mutations (sPD) were included. We assessed motor impairment with the Unified Parkinson's Disease Rating Scale-III. Nonmotor symptoms were evaluated using the Montreal Cognitive Assessment, Neuropsychiatric Inventory, revised form of the Beck Depression Inventory, Parkinson Disease Sleep Scale, Sniffin' Sticks, and Unified Multiple System Atrophy Rating Scale items 9-12. TCS imaging was used to detect morphologic characteristics.

RESULTS

Patients with GBA-PD more often had a variety of nonmotor symptoms, namely dementia, neuropsychiatric disturbances, and autonomic dysfunction, and had more severe cases, than patients with sPD. They also demonstrated a higher prevalence of a reduced echogenicity of the brainstem raphe assessed by TCS.

CONCLUSIONS

Especially nonmotor symptoms seem to be very common in GBA-PD. Further studies are needed to validate these observations in order to better understand the pathogenesis of GBA-PD and develop specific therapeutic concepts.

AFQ056 treatment of levodopa-induced dyskinesias: results of 2 randomized controlled trials

Study objectives were to assess the efficacy, safety, and tolerability of AFQ056 in Parkinson's disease patients with levodopa-induced dyskinesia. Two randomized, double-blind, placebo-controlled, parallel-group, in-patient studies for Parkinson's disease patients with moderate to severe levodopa-induced dyskinesia (study 1) and severe levodopa-induced dyskinesia (study 2) on stable dopaminergic therapy were performed. Patients received 25-150 mg AFQ056 or placebo twice daily for 16 days (both studies). Study 2 included a 4-day down-titration. Primary outcomes were the Lang-Fahn Activities of Daily Living Dyskinesia Scale (study 1), the modified Abnormal Involuntary Movement Scale (study 2), and the Unified Parkinson's Disease Rating Scale-part III (both studies). Secondary outcomes included the Unified Parkinson's Disease Rating Scale-part IV items 32-33. The primary analysis was change from baseline to day 16 on all outcomes. Treatment differences were assessed. Fifteen patients were randomized to AFQ056 and 16 to placebo in study 1; 14 patients were randomized to each group in study 2. AFQ056-treated patients showed significant improvements in dyskinesias on day 16 versus placebo (eg, Lang-Fahn Activities of Daily Living Dyskinesia Scale, P = .021 [study 1]; modified Abnormal Involuntary Movement Scale, P = .032 [study 2]). No significant changes were seen from baseline on day 16 on the Unified Parkinson's Disease Rating Scale-part III in either study. Adverse events were reported in both studies, including dizziness. Serious adverse events (most commonly worsening of dyskinesias, apparently associated with stopping treatment) were reported by 4 AFQ056-treated patients in study 1, and 3 patients (2 AFQ056-treated patient and 1 in the placebo group) in study 2. AFQ056 showed a clinically relevant and significant antidyskinetic effect without changing the antiparkinsonian effects of dopaminergic therapy. © 2011 Movement Disorder Society.

[On the role of MAO B inhibitors and NMDA antagonists in the therapy of Parkinson's disease]

In this workshop report, the N-methyl-D-aspartate (NMDA) receptor antagonists and the monoamine oxidase (MAO) type B inhibitors are discussed with respect to their role in the pharmacotherapy of Parkinson's Disease (PD). For the NMDA antagonist amantadine, studies demonstrated beneficial effects in various symptoms of the PD complex, while memantine seems to be beneficial in the treatment of cognitive deficits in PD-associated dementia. The MAO B inhibitors selegiline and rasagiline are in use for PD pharmacotherapy; for rasagiline, studies have demonstrated a possible disease-modifying effect. Although not supported by specific controlled studies, a "triple" early therapy is discussed which consists of a dopamine agonist, a MAO B inhibitor and amantadine, in order to try to delay the start of levodopa therapy.

Ceruloplasmin gene variations and substantia nigra hyperechogenicity in Parkinson disease

BACKGROUND

Transcranial ultrasound may be used to detect increased iron levels of the substantia nigra (SN) in patients with Parkinson disease (PD) and in control subjects. It is not known whether iron accumulation in PD is a primary or secondary phenomenon. However, sequence variations in genes involved in iron metabolism have been linked to basal ganglia disorders. One of these is ceruloplasmin (Cp), which is vitally involved in iron transport across the cell membrane.

METHODS

One hundred seventy-six patients with PD according to the UK Brain Bank criteria and 180 ethnically matched control subjects, who were previously examined for SN iron signal changes by transcranial ultrasound, were examined for mutations in the Cp gene using denaturing high-performance liquid chromatography and subsequent sequencing for verification of unequivocal signals. Immunohistochemistry of PD midbrains was performed to examine the presence of Cp in Lewy bodies.

RESULTS

Five novel missense variations were detected. One of these (I63T) was found in a single PD patient. A known variation (D554E) was significantly associated with PD and the ultrasound marker for increased SN iron levels. Moreover, a third sequence variation (R793H) was found to segregate with the ultrasound marker for increased iron levels in patients and control subjects. Immunohistochemistry demonstrated that Cp co-localizes with Lewy bodies in PD.

CONCLUSIONS

Detection of sequence variations in a single Parkinson disease (PD) patient or associated with the ultrasound marker for increased substantia nigra iron levels and the presence of ceruloplasmin (Cp) immunoreactivity in Lewy bodies underline a suspected role for Cp in the pathogenesis of PD. Further functional analyses are warranted to investigate whether these variations are causally linked to the complex pathogenesis of PD in a subset of cases.

[Differentiation of atypical Parkinson syndrome and delineation from idiopathic Parkinson syndrome with routine magnetic resonance tomography]

Atrophy of frontal lobe, midbrain, pons, and cerebellum was studied in 16 patients with progressive supranuclear palsy (PSP), 14 with multiple system atrophy of striatonigral type (MSA-P), 20 with idiopathic Parkinson's disease (IPS), and 12 age-matched healthy controls using axial T2-weighted MR images (1.5 Teslar). With <16 mm, the PSP group showed significantly lower anteroposterior midbrain diameters than the IPS, MSA-P, and control groups. We conclude that measurement of the anteroposterior diameter of the midbrain with axial T2-weighted MRI is a useful feature and should be incorporated into the diagnostic criteria for PSP. In addition to the typical slit hyperintensity in margin of putamen and decreased signal intensity in dorsolateral putamen, we found cerebellar atrophy in 64% of patients with MSA-P. Before now, this was considered a typical sign of multiple system atrophy of cerebellar type (MSA-C). The use of this feature in the differential diagnosis of both types of multiple system atrophy is debatable.

Psychopathological symptoms of depression in Parkinson's disease compared to major depression

Parkinson's disease is frequently associated with depressive symptoms. When depression occurs at early stages and before the onset of characteristic motor symptoms of the disease, differential diagnosis of major depression may be difficult. Differences in psychopathological features of depression in Parkinson's disease and major depression have been reported by some authors. This study presents data of 49 patients with depression in Parkinson's disease and 38 patients with major depression. The severity of depressive symptoms was equivalent in both groups. Depressive features did not differ between the two groups with exception of affective flattening, delusional ideas and suicide attempts. In conclusion, this investigation gives support to the assumption of a common neurobiological origin of depression in Parkinson's disease and major depression.

Differentiation of parkinsonian syndromes according to differences in executive functions

Groups of patients with Parkinson's disease (PD), striatonigral degeneration-type multiple system atrophy (MSA) or progressive supranuclear palsy (PSP) with motor disability stages II and III according to Hoehn and Yahr, and a healthy control group were compared using neuropsychological tests of executive functions. The results indicate that all three patient groups were impaired in the tests of executive functions. In comparison with healthy subjects, the three patient groups showed impaired performance regarding verbal fluency, problem solving and verbal and figural working memory. Patients with PD differed significantly from healthy subjects in a test of verbal recency, while patients with MSA or PSP were unimpaired. The comparison of patient groups revealed no differences between PD and MSA patients. However, patients with PSP showed greater impairment in both phonemic and semantic fluency than patients with PD or MSA. Using discriminant function analysis, it was found that variables derived from four verbal fluency tasks (simple and alternate semantic and phonemic fluency) discriminated among the three patient groups at a level significantly exceeding chance. Over 90% of patients with PSP were correctly classified. Patients with PD and MSA were correctly classified in over 70% of cases. These results suggest that verbal fluency tasks may be sensitive measures in the differential diagnosis of PD, MSA and PSP.

Measurement of the midbrain diameter on routine magnetic resonance imaging: a simple and accurate method of differentiating between Parkinson disease and progressive supranuclear palsy

Anteroposterior diameters of the suprapontine midbrain, the pons, and the collicular plate were measured in 50 patients with various parkinsonian syndromes (Parkinson disease [PD] [n = 20], progressive supranuclear palsy [PSP] [n = 16], and multiple-system atrophy of striatonigral type [n = 14]) and 12 age-matched healthy control subjects by means of axial T2-weighted magnetic resonance images. While no differences in midbrain diameter were found between patients with PD (mean, 18.5 mm) and control subjects (mean, 18.2 mm), patients with PSP had significantly lower midbrain diameters (mean, 13.4 mm) than patients with PD and control subjects (P<.001), without any overlap between these 2 groups. However, midbrain diameters of patients with multiple-system atrophy were also significantly lower than those of control subjects and patients with PD, with individual values showing overlap with the PSP, PD, and control groups. Pontine and collicular plate diameters did not contribute additional information. We therefore conclude that measurement of anteroposterior diameter of the midbrain on axial T2-weighted magnetic resonance images is a reliable means to differentiate patients with PSP from those with PD and should be incorporated into the diagnostic criteria for PSP.