Neuropsychiatric Features of Punding and Hobbyism in Parkinson's Disease.

BACKGROUND: Little is known about the cognitive and neuropsychiatric profile associated with punding and hobbyism in Parkinson's disease (PD). OBJECTIVE: To compare the clinical and neuropsychological features of PD patients with punding and hobbyism to PD controls. METHODS: The Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS) was used as a screening tool, and a structured interview was used to diagnose punding/hobbyism. Clinical and neuropsychological assessment was conducted with validated questionnaires/scales. RESULTS: Twenty-one patients with PD and punding (PD + pu) were compared to 26 with hobbyism (PD + h) and 25 PD controls. PD + pu patients showed higher levels of anxiety, non-motor symptoms and motor symptoms, and lower Frontal Assessment Battery scores. The PD + h group exhibited similar levels of anxiety and motor fluctuations to the PD + pu group. CONCLUSION: PD + pu showed increased anxiety and frontal lobe dysfunction, similar to PD + h. Hobbyism could be a prodromal phase with increased risk of leading to punding.

Scales to assess impulsive and compulsive behaviors in Parkinson's disease: Critique and recommendations.

Impulse control disorders (ICDs) and related impulsive and compulsive behaviors (together called ICBs) have been increasingly recognized in the context of Parkinson's disease (PD) and treatment. The International Parkinson's and Movement Disorder Society commissioned a task force to assess available clinical screening instruments and rating scales, including their clinimetric properties, make recommendations regarding their utility, and suggest future directions in scale development and validation. The literature was systematically searched for scales measuring a range of reported ICBs in PD. A scale was designated "recommended" if the scale had been employed in PD studies, been used beyond the group that developed it, and had adequate clinimetric data published for PD. Numerous diagnostic screening tools and severity rating scales were identified for a range of ICBs, including compulsive medication use, punding/hobbyism, walkabout, pathological gambling, hypersexuality, compulsive or binge eating, compulsive buying, reckless driving, compulsive exercise, pyromania, trichotillomania, hoarding, kleptomania, intermittent explosive disorder, and internet addiction. For screening across the range of ICBs (except compulsive medication use), the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's disease (QUIP) and QUIP-Rating Scale (QUIP-RS) are recommended, and for severity rating across the range of ICBs the QUIP-RS and the Ardouin Scale of Behavior in Parkinson's Disease are recommended. The Scale for Outcomes in Parkinson's Disease-Psychiatric Complications is recommended for rating of hypersexuality and the compulsive behaviors gambling/shopping. Further testing of established scales against gold standard diagnostic criteria is urgently required for all other individual ICBs in PD. © 2019 International Parkinson and Movement Disorder Society © 2019 International Parkinson and Movement Disorder Society.

Phenomenology and epidemiology of impulsive-compulsive behaviours in Parkinson's disease, atypical Parkinsonian disorders and non-Parkinsonian populations.

Impulsive-compulsive behaviours are common, quality of life affecting consequences of dopamine replacement therapy which are well recognized in patients with idiopathic Parkinson's disease. Details of the occurrence and nature of these disorders in the atypical parkinsonian neurodegenerative disorders, and in non-Parkinson's patients prescribed dopaminergic stimulation for other disease processes, are slowly emerging. Here we review what is known about the phenomenology, epidemiology and risk factors for impulsive-compulsive behaviours in Parkinson's disease and in other, less well studied, patient groups. By analyzing the available published data, this review identifies potential clues as to the underlying neurobiological mechanism of these disorders, and further identifies critical gaps yet to be addressed.

Palliative care for Parkinson's disease: Patient and carer's perspectives explored through qualitative interview.

BACKGROUND: Palliative care is recommended for non-malignant illnesses, including Parkinson's disease. However, past research with healthcare workers highlights unmet palliative needs in this population and referral rates to Specialist Palliative Care are low. Some healthcare workers perceive a 'fear' in their patients about introducing palliative care. However, less is known about the views of people with Parkinson's disease and their carers about palliative care. AIM: (1) To explore the palliative care and related issues most affecting people with Parkinson's disease and their families and (2) to examine perceptions about/understanding of palliative care. DESIGN: This was a qualitative study; semi-structured interviews were conducted, transcribed and analysed using thematic analysis. SETTING/PARTICIPANTS: A total of 31 people participated, both people with Parkinson's disease ( n = 19) and carers ( n = 12), across three Movement Disorder Clinics in the Republic of Ireland. RESULTS: People with Parkinson's disease and their carers were unfamiliar with the term palliative care. When informed of the role of palliative care, most felt that they would benefit from this input. People with Parkinson's disease and carers experienced a high illness burden and wanted extra support. Crises requiring Specialist Palliative Care involvement may occur at diagnosis and later, with advancing illness. Participants wanted more information about palliative care and especially further supports to address their psychosocial needs. CONCLUSION: A holistic palliative care approach could address the complex physical and psychosocial symptoms experienced by people with Parkinson's disease and their carers, and people with Parkinson's disease and their carers are open to palliative care. Further research needs to explore how palliative care can be introduced into the routine care for people with Parkinson's disease.

A genome-wide association study in multiple system atrophy.

OBJECTIVE: To identify genetic variants that play a role in the pathogenesis of multiple system atrophy (MSA), we undertook a genome-wide association study (GWAS). METHODS: We performed a GWAS with >5 million genotyped and imputed single nucleotide polymorphisms (SNPs) in 918 patients with MSA of European ancestry and 3,864 controls. MSA cases were collected from North American and European centers, one third of which were neuropathologically confirmed. RESULTS: We found no significant loci after stringent multiple testing correction. A number of regions emerged as potentially interesting for follow-up at p < 1 × 10-6, including SNPs in the genes FBXO47, ELOVL7, EDN1, and MAPT. Contrary to previous reports, we found no association of the genes SNCA and COQ2 with MSA. CONCLUSIONS: We present a GWAS in MSA. We have identified several potentially interesting gene loci, including the MAPT locus, whose significance will have to be evaluated in a larger sample set. Common genetic variation in SNCA and COQ2 does not seem to be associated with MSA. In the future, additional samples of well-characterized patients with MSA will need to be collected to perform a larger MSA GWAS, but this initial study forms the basis for these next steps.

Apomorphine: A potential modifier of amyloid deposition in Parkinson's disease?

INTRODUCTION: Evidence from clinical and pathological studies suggests a role for both alpha-synuclein and amyloid-beta in the pathophysiology of dementia associated with PD. Recent work demonstrated improvement in memory and reduced amyloid-beta burden in transgenic murine Alzheimer's models given subcutaneous apomorphine. The aim of this work was to determine whether antemortem exposure to apomorphine was associated with lower levels of amyloid-beta in brain tissue in a clinicopathological study of PD. METHODS: The case notes of donors with pathologically proven PD who had (n = 36) and had not received apomorphine (n = 35) during life for motor complications were reviewed to determine presence or absence of cognitive impairment. The four groups were well matched for disease duration, age at death, sex, and apolipoprotein E4 genotype. The severity of amyloid-beta mature/diffuse plaque load, tau pathology, and alpha-synuclein pathology were all established. Cerebral amyloid angiopathy was determined based on a four-tier grading system. RESULTS: Within the cognitively normal cases, significantly reduced amyloid-beta deposition was present in those with antemortem apomorphine exposure; this finding was not replicated in those with cognitive impairment plus previous apomorphine use. In the apomorphine cognitively normal group only, a significant negative association was observed between maximum apomorphine dose received and amyloid-beta burden. Early and maximum doses of apomorphine plus apolipoprotein genotype and sex were significant predictors of total plaque load in an explanatory model. CONCLUSION: This exploratory study suggests that apomorphine may have a modifying effect on amyloid deposition in nondemented PD cases and thus may represent a potential therapy to reduce cognitive impairment in PD. © 2015 Movement Disorder Society.

Jumping to conclusions in untreated patients with Parkinson's disease.

BACKGROUND: Jumping to conclusions due to impulsivity has been shown to be a sensitive marker for dopamine dysregulation and addictive behaviour patterns in treated patients with Parkinson's disease (PD). It is unknown whether drug naïve PD patients, who have never received dopaminergic therapy also have deficits in information sampling. METHODS: Twenty five de novo PD patients and twenty matched healthy controls were recruited and tested on the beads task, which is a validated information sampling task to assess reflection impulsivity and a temporal discounting questionnaire. RESULTS: Patients gathered significantly less information and made more irrational choices than matched controls. There was, however, no group difference on the temporal discounting questionnaire. CONCLUSIONS: Poor information sampling and irrational decision making may be an inherent component of the neuropsychological deficit in Parkinson's disease. These findings suggest that underlying impulsivity detected by a metric task is common in de novo PD.

Interviews with Irish healthcare workers from different disciplines about palliative care for people with Parkinson's disease: a definite role but uncertainty around terminology and timing.

BACKGROUND: An integrated palliative care approach is recommended in all life-limiting diseases, including Parkinson's disease (PD). However research shows that people with PD have unmet palliative care needs. The study aimed to explore multidisciplinary healthcare workers' (HCWs) views on palliative care for people with PD, identifying perceived barriers and facilitators. METHODS: A qualitative design was used; data was analysed using Thematic Analysis. Semi-structured interviews were conducted with 30 HCWs, working either with people with PD or in a palliative care setting in Ireland. RESULTS: A number of perceived barriers were evident helping to account for the previously reported unmet palliative care needs in PD. A lack of education about PD and palliative care meant that HCWs were unsure of the appropriateness of referral, and patients and carers weren't equipped with information to seek palliative care. A lack of communication between PD and palliative care specialists was seen to impede collaboration between the disciplines. Uncertainty about the timing of palliative care meant that it was often not introduced until a crisis point, despite the recognised need for early planning due to increased prevalence of dementia. CONCLUSIONS: Most HCWs recognised a need for palliative care for people with PD; however several barriers to implementing a palliative care approach in this population need to be addressed. Implications for clinical practice and policy include the need for an integrated model of care, and education for all HCWs, patients, carers, and the public on both the nature of advanced PD, and the potential of palliative care in support of patients and their family members.

Psychogenic and neural visual-cue response in PD dopamine dysregulation syndrome.

INTRODUCTION: Dopamine dysregulation syndrome (DDS) in Parkinson's disease (PD) patients refers to the compulsive use of dopaminergic replacement therapy and has serious psycho-social consequences. Mechanisms underlying DDS are not clear although has been linked to dysfunctional brain reward networks. METHODS: With fMRI, we investigate behavioral and neural response to drug-cues in six PD DDS patients and 12 PD control patients in both the ON and OFF medication state. Behavioral measures of liking, wanting and subjectively 'feeling ON medication' were also collected. RESULTS: Behaviorally, PD DDS patients feel less ON and want their drugs more at baseline compared to PD controls. Following drug-cue exposure, PD DDS patients feel significantly more ON medication, which correlates with significant increases in reward related regions. CONCLUSIONS: The results demonstrate that exposure to drug-cues increases the subjective feeling of being 'ON' medication which corresponds to dysfunctional activation in reward related regions in PD DDS patients. These findings should be extended in future studies. Visual stimuli being sufficient to elicit behavioral response through neuroadaptations could have direct implications to the management of addictive behavior.

Morphometric changes in the reward system of Parkinson's disease patients with impulse control disorders.

Impulse control disorders (ICDs) occur in a subset of patients with Parkinson's disease (PD) who are receiving dopamine replacement therapy. In this study, we aimed to investigate structural abnormalities within the mesocortical and limbic cortices and subcortical structures in PD patients with ICDs. We studied 18 PD patients with ICDs, 18 PD patients without ICDs and a group of 24 age and sex-matched healthy controls. Cortical thickness (CTh) and subcortical nuclei volume analyses were carried out using the automated surface-based analysis package FreeSurfer (version 5.3.0). We found significant differences in MRI measures between the three groups. There was volume loss in the nucleus accumbens of both PD patients with ICDs and without ICDs compared to the control group. In addition, PD patients with ICDs showed significant atrophy in caudate, hippocampus and amygdala compared to the group of healthy controls. PD patients with ICDs had significant increased cortical thickness in rostral anterior cingulate cortex and frontal pole compared to PD patients without ICDs. Cortical thickness in rostral anterior cingulate and frontal pole was increased in PD patients with ICDs compared to the control group, but the differences failed to reach corrected levels of statistical significance. PD patients with ICDs showed increased cortical thickness in medial prefrontal regions. We speculate that these findings reflect either a pre-existing neural trait vulnerability to impulsivity or the expression of a maladaptive synaptic plasticity under non-physiological dopaminergic stimulation.

Rodent models of impulsive-compulsive behaviors in Parkinson's disease: How far have we reached?

There is increasing awareness that the medications used to treat the motor symptoms of Parkinson's disease (PD) contribute to the development of behavioral addictions, which have been clinically defined as impulsive-compulsive behaviors (ICBs). These features include pathological gambling, compulsive sexual behavior, binge eating, compulsive shopping, excessive hobbyism or punding, and the excessive use of dopaminergic medication. ICBs frequently have devastating effects on the social and occupational function of the affected individuals as well as their families. Although ICBs are an important clinical problem in PD, the number of studies in which these symptoms have been modeled in rodents is still limited. This may depend on uncertainties regarding, on one hand, the pathophysiology of these behaviors and, on the other hand, the experimental paradigms with which similar features can be induced in rodents. To help compose these uncertainties, we will here review the characteristics of ICBs in PD patients and then describe behavioral methods to approximate them in rodents. We will discuss both the challenges and the possibilities of applying these methods to animals with PD-like lesions, and review the recent progress made to this end. We will finally highlight important questions deserving further investigation. Rodent models having both face validity and construct validity to parkinsonian ICBs will be essential to further pathophysiological and therapeutic studies into this important area.

Single versus multiple impulse control disorders in Parkinson's disease: an ¹¹C-raclopride positron emission tomography study of reward cue-evoked striatal dopamine release.

Impulse control disorders (ICDs) are reported in Parkinson's disease (PD) in association with dopaminergic treatment. Approximately 25 % of patients with ICDs have multiple co-occurring ICDs (i.e. more than one diagnosed ICD). The extent to which dopaminergic neurotransmission in PD patients with multiple ICDs differs from those with only one diagnosed ICD is unknown. The aims of this study are: (1) to investigate dopamine neurotransmission in PD patients diagnosed with multiple ICDs, single ICDs and non-ICD controls in response to reward-related visual cues using positron emission tomography with (11)C-raclopride. (2) to compare clinical features of the above three groups. PD individuals with mulitple ICDs (n = 10), single ICD (n = 7) and no ICDs (n = 9) were recruited and underwent two positron emission tomography (PET) scans with (11)C-raclopride: one where they viewed neutral visual cues and the other where they viewed a range of visual cues related to different rewards. Individuals with both multiple ICDs and single ICDs showed significantly greater ventral striatal dopamine release compared to non-ICD PD individuals in response to reward cues, but the two ICD groups did not differ from each other in the extent of dopamine release. Subjects with multiple ICDs were, however, significantly more depressed, and had higher levels of impulsive sensation-seeking compared to subjects with single ICDs and without ICDs. This is the first study to compare dopamine neurotransmission using PET neuroimaging in PD subjects with multiple vs. single ICDs. Our results suggest that striatal dopamine neurotransmission is not directly related to the co-occurrence of ICDs in PD, potentially implicating non-dopaminergic mechanisms linked to depression; and suggest that physicians should be vigilant in managing depression in PD patients with ICDs.

Serotonergic markers in Parkinson's disease and levodopa-induced dyskinesias.

Preclinical animal models implicate serotonin neurons in the pathophysiology of levodopa (l-dopa)-induced dyskinesias in Parkinson's disease (PD), but effective treatment remains elusive. We examined the relationship between serotonin and l-dopa-induced dyskinesias in a pathologically confirmed cohort of PD patients. We obtained brain tissue from 44 PD cases and 17 age-matched controls and assessed monoamine levels and the serotonin and dopamine transporters in the striatum, and the extent of dopaminergic and serotonergic cell preservation in the substantia nigra (SN) and the dorsal raphe nuclei (DRN), respectively. As expected, PD patients demonstrated a severe loss of all dopaminergic markers, including dopamine (P < 0.0001) and the dopamine transporter (P < 0.0001) in the striatum, and dopaminergic neurons (P < 0.001) in the SN, compared with controls. Marked serotonin loss was observed in the caudate (but not putamen) in PD patients compared with controls (P < 0.001), but no difference was found in the levels of the serotonin transporter in the striatum or density of serotonergic neurons in the DRN between these groups, suggesting a functional but not structural change in the serotonergic system in PD. No difference was seen in levels of serotonergic and dopaminergic markers in the striatum between PD patients with and without dyskinesias, or between cases separated according to the clinical severity of their dyskinesias. The absence of a correlation between striatal serotonin markers and the incidence and severity of l-dopa-induced dyskinesias suggests that an intact and functioning serotonergic system is not a risk factor for developing dyskinesias in PD.

Survey of Health Care Workers Suggests Unmet Palliative Care Needs in Parkinson's Disease.

The aim of this study was to investigate the knowledge, attitudes, and previous training of Irish health care workers (HCWs) in palliative care in end-stage Parkinson's disease (PD). A survey was distributed to HCWs, including neurologists, geriatricians, general practitioners, nurses, and allied health professionals, in acute and community settings in the Republic of Ireland. Three-hundred and six surveys were returned (32% average response rate). Most HCWs (90%) believed that people with PD have palliative care needs; however, 76% of HCWs also said that these needs are "never" or only "sometimes" met. These unmet needs are reflected in relatively few people with PD being referred to specialist palliative care; 48% of hospital consultants had referred no patients in the previous 6 months, and just 7% had referred more than 10. Just 8% of the HCWs surveyed reported having any training on the palliative care aspects of PD, and 97% expressed an interest in receiving further education. Respondents wanted all topics pertinent to palliative care in PD covered, and many felt that they also needed further information on PD in general. People with PD are seen to have palliative care needs; however, the findings suggest that these needs are not being met. There is a discrepancy between best practice recommendations for palliative care in PD and the beliefs and practices of HCWs. Further education in palliative care in PD is needed to ensure better quality of care for people with PD.