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Background and Aims: Neurodegeneration underpins the pathological processes of younger‐onset dementia (YOD) and has been implicated in primary psychiatric disorders (PSYs). Cerebrospinal fluid (CSF) neurofilament light (NfL) has been used to investigate neurodegeneration severity through correlation with structural brain changes in various conditions, but has seldom been evaluated in YOD and PSYs. Methods: This retrospective study included patients with YOD or PSYs with magnetic resonance imaging (MRI) of the brain and CSF NfL analysis. Findings from brain MRI were analysed using automated volumetry (volBrain) to measure white matter (WM), grey matter (GM) and whole brain (WB) volumes expressed as percentages of total intracranial volume. Correlations between NfL and brain volume measurements were computed whilst adjusting for age. Results: Seventy patients (47 with YOD and 23 with PSY) were identified. YOD types included Alzheimer disease and behavioural variant frontotemporal dementia. PSY included schizophrenia and major depressive disorder. MRI brain sequences were either fast spoiler gradient‐echo (FSPGR) or magnetization‐prepared rapid acquisition gradient‐echo (MPRAGE). In the total cohort, higher NfL was associated with reduced WB in the FSPGR and MPRAGE sequences (r = −0.402 [95% confidence interval (CI), −0.593 to −0.147], P = 0.008 and r = −0.625 [95% CI, −0.828 to −0.395], P < 0.001, respectively). Higher NfL was related to reduced GM in FSPGR (r = 0.385 [95% CI, −0.649 to −0.014], P = 0.017) and reduced WM in MPRAGE (r = −0.650 [95% CI, −0.777 to −0.307], P < 0.001). Similar relationships were seen in YOD, but not in PSY. Conclusion: Higher CSF NfL is related to brain atrophy in YOD, further supporting its use as a nonspecific marker of neurodegeneration severity. [ABSTRACT FROM AUTHOR]

Background: Although the COVID‐19 pandemic is affecting a relatively small proportion of the global population, its effects have already reached everyone. The pandemic has the potential to differentially disadvantage chronically ill patients, including those with Parkinson's disease (PD). The first health care reaction has been to limit access to clinics and neurology wards to preserve fragile patients with PD from being infected. In some regions, the shortage of medical staff has also forced movement disorders neurologists to provide care for patients with COVID‐19. Objective: To share the experience of various movement disorder neurologists operating in different world regions and provide a common approach to patients with PD, with a focus on those already on advanced therapies, which may serve as guidance in the current pandemic and for emergency situations that we may face in the future. Conclusion: Most of us were unprepared to deal with this condition given that in many health care systems, telemedicine has been only marginally available or only limited to email or telephone contacts. In addition, to ensure sufficient access to intensive care unit beds, most elective procedures (including deep brain stimulation or the initiation of infusion therapies) have been postponed. We all hope there will soon be a time when we will return to more regular hospital schedules. However, we should consider this crisis as an opportunity to change our approach and encourage our hospitals and health care systems to facilitate the remote management of chronic neurological patients, including those with advanced PD. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In Australia 1% of individuals aged over 50 years have Parkinson disease ( PD). Guidance for commencing device-assisted therapies ( DAT) for PD in Australia was developed based on a review of European recommendations and their relevance to the local clinical setting. An online survey and teleconference discussions were held by a group of eight local movement disorder experts to develop consensus. Referral to a movement disorder specialist and consideration of DAT is appropriate when motor fluctuations cause disability or reduced quality of life, response to treatment is inconsistent or motor fluctuations and dyskinesias require frequent treatment adjustment without apparent benefit and levodopa is required four or more times daily. Three types of DAT are available in Australia for patients with PD: continuous subcutaneous apomorphine; continuous levodopa-carbidopa intestinal gel infusion; and deep brain stimulation. All improve consistency of motor response. The most important aspects when considering which DAT to use are the preferences of the patient and their carers, patient comorbidities, age, cognitive function and neuropsychiatric status. Patients and their families need to be provided with treatment options that are suitable to them, with adequate explanations regarding the recommendations and comparison of potential device-related complications. DAT are best managed, where possible, in a specialist centre with experience in all three types of therapy. Proactive and early management of symptoms during disease progression is essential to maintain optimally motor responses and quality of life in patients with PD. [ABSTRACT FROM AUTHOR]

Background Sleep benefit ( SB) in Parkinson's disease refers to improved motor symptoms upon waking despite an entire night without medications. Although it was first proposed 30 years ago, this phenomenon proved difficult to investigate, and its true prevalence and underlying mechanisms remain unclear. Objective This study aimed to identify and quantify SB through measurement of motor function using a validated smartphone application and to identify disease characteristics that predicted SB. Methods Ninety-two patients recruited from 2 Movement Disorder Services were clinically assessed at home using a validated smartphone application. Each patient was tested in the on-state, at the end of dose, and on waking (before medications) 3 times. Differences between the 3 states were used to determine the impact of sleep and levodopa on motor function. SB was considered to be a 'measurable improvement in parkinsonism from the end of dose.' Results The morning waking motor function of 20 patients (22%) improved compared with the end-of-dose function, with 9 patients demonstrating superior function compared with their on-state. No clinical features predicted SB. Although all participants subjectively reported motor fluctuations, only 35 patients (38%) demonstrated an objective improvement with levodopa. Patients who had SB more often demonstrated objective motor fluctuations compared with those who did not (65% vs. 31%; P = 0.008). Conclusions SB is a genuine motor phenomenon: 1 in 5 patients have a measurable improvement in motor function on waking. It remains questionable whether this improvement is a direct effect of sleep. Until its underlying mechanism is better understood, it is more appropriate to refer to this phenomenon as simply morning improvement or diurnal fluctuation of motor symptoms. [ABSTRACT FROM AUTHOR]

Background: Distinguishing a dementia syndrome from a primary psychiatric disease in younger patients can be challenging and may lead to diagnostic change over time. The aim of this study was to examine diagnostic stability in a cohort of patients with younger‐onset neurocognitive disorders. Method: We retrospectively reviewed records of patients that were admitted to our unit between 2000 and 2019, were followed‐up for ≥12 months and received a diagnosis of young onset dementia at any time point. Initial diagnosis included Alzheimer disease (AD)‐type dementia (n= 30), frontotemporal dementia (FTD) syndromes (n=44), vascular dementia (VaD, n=7), mild cognitive impairment (MCI, n= 10), primary psychiatric diseases (n=6) and other conditions such as Lewy Body Dementia (n=30). Result: In a total of n=127 patients, 49 (39%) changed their initial diagnoses during follow‐up. Behavioural variant FTD (bvFTD) was the least stable diagnosis, followed by dementia not otherwise specified and MCI. Compared to patients with a stable diagnosis, those who changed exhibited: a higher cognitive score at baseline, a longer follow‐up period, greater delay to final diagnosis, and no family history of dementia. Patients switching from a neurodegenerative to a psychiatric diagnosis more likely had a long psychiatric history, while those changing from a psychiatric to a neurodegenerative diagnosis had a recent manifestation of psychiatric symptoms. Conclusion: Misdiagnosis in younger patients with neurocognitive disorders is not uncommon, especially in cases of behavioural variant FTD. Late‐onset psychiatric symptoms may be the harbinger to a neurodegenerative disease. Close follow‐up and monitoring of these patients are necessary. [ABSTRACT FROM AUTHOR]

Impulse control disorders (ICDs), including compulsive gambling, buying, sexual behavior, and eating, are a serious and increasingly recognized psychiatric complication in Parkinson's disease (PD). Other impulsive-compulsive behaviors (ICBs) have been described in PD, including punding (stereotyped, repetitive, purposeless behaviors) and dopamine dysregulation syndrome (DDS; compulsive PD medication overuse). ICDs have been most closely related to the use of dopamine agonists (DAs), perhaps more so at higher doses; in contrast, DDS is primarily associated with shorter-acting, higher-potency dopaminergic medications, such as apomorphine and levodopa. Possible risk factors for ICDs include male sex, younger age and younger age at PD onset, a pre-PD history of ICDs, and a personal or family history of substance abuse, bipolar disorder, or gambling problems. Given the paucity of treatment options and potentially serious consequences, it is critical for PD patients to be monitored closely for development of ICDs as part of routine clinical care. © 2014 International Parkinson and Movement Disorder Society [ABSTRACT FROM AUTHOR]

Background: There are currently 28000 people in Australia with younger‐onset dementia (YOD). A recent review of younger‐onset dementia cohorts (Loi SM et al. submitted) suggested that there needs to be more detailed study in this heterogenous group in order to glean more clinically relevant information. For example, our group (Eratne D et al. 2020) investigated the utility of cerebrospinal fluid (CSF) neurofilament light (NfL) chain in a group of people with a range of psychiatric and neurodegenerative disorders and reported that NfL could distinguish between these two broad disorders, demonstrating the benefits in studying a large range of YODs. BeYOND (Biomarkers in younger‐onset neurocognitive disorders) was established as a longitudinal cohort of younger people presenting with neurocognitive symptoms to a clinical diagnostic service, with the aim of identifying clinical and investigational biomarkers which can inform diagnostic and psychosocial outcomes in a clinically heterogenous population. Method: Patients are prospectively recruited during their index presentation to Neuropsychiatry, Royal Melbourne Hospital, Australia. Neuropsychiatry is a tertiary specialist service which provides diagnostic work‐up for patients with cognitive, psychiatric and neurological symptoms. The diagnostic process includes baseline and 18 month assessments of clinical and diagnostic outcomes including CSF and blood biomarkers, cognition, neuroimaging and psychosocial (including caregiver). Results: To date, 50 participants have been recruited (17 females, mean age 55). Thirty of had a dementia diagnosis (including Alzheimer's dementia, frontotemporal dementia and Huntington's disease), with the remainder having a psychiatric disorder (including depression and schizophrenia) as principle diagnosis. All participants have had clinical, neuropsychology and imaging. Eleven have had a lumbar puncture. Twenty participants have had a research blood panel for genetic analysis)and 12 had quantitative susceptibility mapping imaging. Conclusion: The diagnosis of neurodegenerative disorders in younger people can be difficult and is often associated with diagnostic delays (Draper B et al. 2016). The BeYOND study aims to longitudinally assess younger patients with suspected neurodegenerative disease in order to improve diagnostic and psychosocial outcomes for this population. References: Loi SM et al. J Neuropsychiatry Clin Neuroscience. Submitted 23/1/2020. Eratne D et al. ANZJP. 54 (1): 57‐67. 2020. Draper B et al. Int J Geriatr Psychiatry. 31 (11): 1217‐1224. 2016. [ABSTRACT FROM AUTHOR]

Background: Distinguishing primary psychiatric disorders (PPD) from neurological/neurodegenerative disorders (NND) is a common diagnostic dilemma in clinical practice. Numerous studies have focused on whether cognitive, neuroimaging or blood/ cerebrospinal fluid (CSF) are of assistance in this clinical scenario. Olfactory impairment has not however been systematically examined as a clinical tool for this purpose. The aim of this study was to identify whether performance in olfactory identification can distinguish NND and PPD. Method: This was a cross‐sectional retrospective study of inpatients assessed in Neuropsychiatry, Royal Melbourne Hospital (RMH) over the period 2015‐2019. Neuropsychiatry is a tertiary / quaternary service which provides diagnostic work up for patients with cognitive, psychiatric and neurological symptoms. Data extracted from the admission records included: demographics, tobacco use, medical comorbidities, cognitive function using the Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG), and odour identification assessed using the Sniffin' Sticks Screening 12 Test (SS12). The final discharge diagnosis for all patients was informed by established diagnostic criteria. Result: 121 patients were identified who had valid Sniffin Stick testing over this period. 88 patients (72.7%) were diagnosed with NND (mean age‐ 60, including Alzheimer's dementia, frontotemporal dementia, Lewy body parkinsonian‐related dementias [Parkinson's disease, Multiple Systematic Atrophy, Dementia with Lewy bodies] and other neurological causes of dementia), 33 patients (27.3%) were diagnosed with PPD (mean age=57 years, including mood and psychotic disorders). Patients who scored ≤8 in SS12 were more likely to have NND than PPD, even after adjustment for age, gender and tobacco use [(p=0.005, unadjusted OR=3.51, 95% CI=1.463,8.410), (p=0.009, adjusted OR=3.848, 95% CI=1.395,10.617)]. Receiver Operating Curve (ROC) analyses demonstrated that a score of ≤8 differentiated NND from PSY with sensitivity of 56.8% and specificity of 72.7% (ROC area under the curve of 0.672, p=0.004). Conclusion: Patients presenting with diagnostically complex neurocognitive / neuropsychiatric difficulties who score 8 or less on Sniffin' Sticks are more likely to have a neurodegenerative illness. A cut‐off score of 8 is potentially a "red‐flag" for clinicians faced with the diagnostic question of PPD versus NND. [ABSTRACT FROM AUTHOR]

Background: Accurate diagnosis of a neurodegenerative disorder, in particular distinguishing primary psychiatric from neurological disorders, can be challenging. There is a need for biomarkers to reduce the diagnostic odyssey and improve outcomes. Neurofilament light (NfL) has shown promise as a biomarker for diagnosis, staging and prognosis in a wide range of disorders. Our 'Biomarkers in Younger Onset Neurocognitive Disorders' (BeYOND) and 'Markers in Neuropsychiatric Disorders' (MiND) studies aim to build on our pilot study (Eratne et al, 2019, ANZJP), to explore the diagnostic and broader utility of plasma and cerebrospinal fluid (CSF) NfL, in a broad range of psychiatric and neurodegenerative/neurological disorders. Method: These studies assess plasma and/or CSF NfL concentrations using Simoa technology in a broad range of cohorts, including: patients assessed for neurocognitive/psychiatric symptoms at Neuropsychiatry and Melbourne Young Onset Dementia service; Australian National Creutzfeldt‐Jakob Disease Registry (ANCJDR); treatment trials in Alzheimer's disease (AD) and frontotemporal dementia (FTD); treatment‐resistant schizophrenia (TRS) biobank; FTD; autoimmune encephalitis; Niemann‐Pick Type C; epilepsy; and patients in primary care with cognitive or psychiatric symptoms. The most recent primary consensus diagnosis informed by established diagnostic criteria is categorised: psychiatric disorder (PSY), neurodegenerative/neurological disorder (NND), or healthy controls (HC). Result: As of January 2020, data from 485 patients/participants (NND:325, PSY:100, HC:60) demonstrates significantly elevated plasma and/or CSF NfL levels in a broad range of NND compared to a broad range of PSY, and HC, with areas under the curve of>0.90 and sensitivity and specificity>90%: improving on results from our pilot study. As recruitment, sample analysis, data collection is ongoing, more detailed, up to date results will be presented from over 600 patients/participants, including in‐depth findings from TRS, ANCJDR, AD and FTD treatment trials, and general practice cohorts. Conclusion: NfL shows great promise as a diagnostic test to assist with the common, but challenging diagnostic dilemma of distinguishing psychiatric from neurodegenerative and neurological disorders. A significantly elevated NfL concentration in a patient with a psychiatric diagnosis should prompt consideration of neurological or neurodegenerative differentials. Plasma NfL could dramatically alter clinical care of patients with neurological/neurodegenerative and psychiatric disorders, improving outcomes for patients, their families, the healthcare system, and clinical trials. [ABSTRACT FROM AUTHOR]

A 56-year-old man presented with gait disturbance, personality change, and behavioral disturbances. He subsequently developed falls, postural instability, and axial rigidity. The cognitive problems progressed and he developed aphasia and later eye movement abnormalities. He died after 9 years of disease. Experts discuss the syndromal diagnosis and predict the underlying pathology. The pathological diagnosis is given and clinical learning points are considered. © 2011 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Hoarding is seen in several psychiatric conditions, but has not been specifically assessed in Parkinson's disease (PD). This study investigates hoarding tendency amongst patients with PD, and its association with impulsive-compulsive spectrum behaviors (ICBs). We compare clinical features, measures of hoarding, impulse buying, self-control, obsessive-compulsive symptoms, depression, and anxiety in 39 patients with PD with ICBs (PD + ICB), 61 patients with PD without ICBs (PD − ICB), and 50 healthy controls. A much higher proportion of PD + ICB (27.8%) than PD − ICB (3.5%) were hoarders ( P = 0.001). 6% of healthy controls were hoarders. Compulsive shoppers scored higher than other varieties of ICB on excessive acquisition measures. Hoarding correlated positively with impulsive buying, obsessive-compulsive symptoms, PD duration, and negatively with self-control measures. Using multivariate regression analyzes, the presence of ICBs and measures of impulsive buying were the only variables independently associated with hoarding in PD. The association of hoarding with other ICBs and low trait impulse control suggests that excessive hoarding is related to the spectrum of impulsive behaviors in PD. © 2010 Movement Disorder Society [ABSTRACT FROM AUTHOR]

A few Parkinson patients develop a disabling pattern of compulsive dopaminergic drug use ('dopamine dysregulation syndrome'-DDS). DDS patients commonly identify aversive dysphoric 'OFF' mood-states as a primary motivation to compulsively use their drugs. We compared motoric, affective, non-motor symptoms and incentive arousal after overnight medication withdrawal and after levodopa in DDS and control PD patients. Twenty DDS patients were matched to 20 control PD patients for age, gender, and disease duration and underwent a standard levodopa challenge. Somatic symptomatology, positive and negative affective states, drug effects, reward responsivity, motor disability, and dyskinesias were tested in the 'OFF'-state after overnight withdrawal of medications, and then after a challenge with a standard dose of levodopa, after a full 'ON'-state was achieved. In the 'OFF'-state, DDS patients reported lower positive affect, and more motor and non-motor disability. In the 'ON'-state, DDS patients had higher expressions of drug 'wanting,' reward responsivity, and dyskinesias. Positive and negative affect, non-motor symptomatology, and motor disability were comparable. These findings suggest that affective, motivational, and motoric disturbances in PD are associated with the transition to compulsive drug use in individuals who inappropriately overuse their dopaminergic medication. © 2010 Movement Disorder Society [ABSTRACT FROM AUTHOR]

There is growing awareness of impulsive-compulsive spectrum behaviors (ICBs) in patients with Parkinson's disease (PD) treated with dopamine replacement therapy (DRT). These include pathological gambling, hypersexuality, compulsive shopping, binge eating, punding and compulsive use of DRT, or dopamine dysregulation syndrome. In PD, difficulties exist in separating the effects of DRT from the underlying disease process and aberrant dopaminergic systems in determining the aetiology of ICBs. Recent reports of ICBs associated with dopamine agonist use for conditions other than PD may suggest a significant etiological role for these medications, but currently published cases thus far lack pathological confirmation of diagnoses. We present three cases of pathologically confirmed progressive supranuclear palsy who developed ICBs in association with dopamine agonist use. Pathological comparisons between these three cases and other case series of progressive supranuclear palsy are made. © 2010 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Antiparkinson therapy can be the primary cause of a range of nonmotor symptoms that include a set of complex disinhibitory psychomotor pathologies and are linked by their repetitive, reward or incentive-based natures. These behaviors relate to aberrant or excessive dopamine receptor stimulation and encompass impulse control disorders (ICDs), punding, and the dopamine dysregulation syndrome (DDS). Common ICDs include pathological gambling, hypersexuality, compulsive eating, and compulsive buying. This review focuses on the phenomenology, epidemiology, and methods to identify and rate these disorders. The management of dopaminergic drug-related compulsive behaviors is discussed in the light of the current understanding of the neurobiological substrate of these disorders. © 2009 Movement Disorder Society [ABSTRACT FROM AUTHOR]

THEME: Clinical manifestations TOPIC: Neuropsychiatry & beh neurology SUBTOPIC: Neuropsychiatry Background: Survival duration in frontotemporal dementia (FTD) remains inconsistent, depending on the clinical phenotype with different risk factors identified. Risk factors to mortality include the FTD‐MND presentation, a genetic predisposition (Agarwal S et al. 2019), deficits in neuropsychological tests, imaging changes (Agarwal et al. 2019; Hodges et al. 2003) and non‐tau pathology (Roberson et al. 2005; Hodges et al. 2003). We aimed to identify survival duration and cause of death in this group. Method: All inpatients admitted to Neuropsychiatry, based at the Royal Melbourne Hospital, in metropolitan Australia from 1992 – 2014, who were diagnosed with probably FTD of any subtype were included. Linkage data was obtained by the Australian Institute of Health and Welfare (AIHW). We reviewed their clinical information including demographics, age of symptom onset, type of presenting symptom, neuroimaging and diagnosis. Result: Of the 528 individual inpatients identified with a dementia, there were n=100 who had a diagnosis of probable FTD. There were n=76 who had a behavioural‐variant FTD (bv‐FTD), n=14 who had a language‐variant FTD (lang‐FTD) and n=10 who had FTD‐MND. 67% of the group had died. Overall median duration of survival was 10.5 years (95% CI 7.9, 12.2). There were no differences in age of death nor age onset between the three FTD‐subtypes (p=0.479, p=0.289, respectively). As expected, there were significant differences in the median survival duration of the three FTD subtypes, with FTD‐MND having the shortest duration (p=0.004). Causes of death based on ICD‐10 were predominantly dementia‐related (26.3% Other degenerative diseases of nervous system; 17.5% unspecified dementia) but also included acute myocardial infarction (7%) and alcohol‐related (7%). Standardised mortality ratios (SMRs) revealed that compared to population norms, people with FTD had 8x mortality rate. Conclusion: Not unsurprisingly, FTD‐MND had the shortest duration compared to the other subtypes of FTD. The duration of survival was comparable to other studies. Causes of death revealed that a dementia was identified in almost half of cases. High SMRs suggest that FTD is a particularly "fatal" type of dementia in younger people. Investigation into risk factors to death is required. [ABSTRACT FROM AUTHOR]

In the past decade, impulse control disorders, punding, and dopamine dysregulation syndrome (which we refer to collectively as disinhibitory psychopathologies) have been increasingly recognized in treated patients with Parkinson's disease. Practicing neurologists must understand these problems to limit potential harm. In this article, we summarize current knowledge regarding these behavioral disorders, including phenomenology, epidemiology, pathophysiology, and treatment. [ABSTRACT FROM AUTHOR]

Plastic changes within the striatum resulting from pulsatile dopaminergic stimulation are thought to lead to dyskinesia in patients with Parkinson's disease (PD). The basal ganglia play a role in processing pain. We hypothesized that the plastic changes that lead to dyskinesia may also mediate pain responses. Our objective was to compare the change in pain sensitivity after levodopa administration between stable responders, fluctuators without dyskinesia, and dyskinetic patients, and to compare pain sensitivity between PD and healthy subjects. Fifty patients with PD were assessed with cold water immersion after overnight withdrawal of dopaminergic medications and again after a standard levodopa challenge, and carefully classified into stable responder (n = 12), fluctuator (n = 15), and dyskinetic (n = 23) groups. Twenty age-matched controls were also tested. PD patients 'off'-medication had a lower threshold ( P = 0.016) and tolerance ( P < 0.0001) to cold pain compared to controls. After levodopa administration, dyskinetic patients experienced a large increase in cold pain threshold (48%) and tolerance (66%) that was absent in stable responders ( P = 0.038 and P = 0.015); there was no significant difference in pain sensitivity change scores between the fluctuator and either the stable responder or dyskinetic groups. Our results suggest that dyskinesia and pain may share common pathophysiological mechanisms in PD. © 2008 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Pathological gambling (PG) has been reported as a complication of the treatment of Parkinson's disease (PD). We examined all published cases of PG for prevalence and risk factors of this complication, the relationship of PG and use of dopamine agonists (DA), and the relationship of PG to the dopamine dysregulation syndrome (DDS). The prevalence of PG in prospective studies of PD patients using DA has been reported between 2.3 and 8%, compared to approximately 1% in the general population. As in the general population, PD patients with this complication are often young, male and have psychiatric co-morbidity. The vast majority are on DA, often at maximum dose or above. Differences between oral DA failed to reach significance. PG associated with levodopa monotherapy is uncommon, but in the majority of cases levodopa is co-prescribed, suggesting possible cross-sensitization of brain systems mediating reward. PG can occur with DDS but often occurs in isolation. In contrast to DDS, escalation and self regulation of anti-parkinsonian medication are not usually seen. PG in patients with PD using DA is higher than PG reported in the general population, but shares similar characteristics and risk factors. PG is predominantly associated with oral DA. It often occurs in isolation and may not be associated with DDS, which typically occurs on treatment with levodopa or subcutaneous apomorphine. [ABSTRACT FROM AUTHOR]

The presence of punding in Parkinson's disease (PD) has been associated with inappropriate excessive use of dopaminergic medication but its relation to the severity of dyskinesias is not known. Through the use of clinical examination and medical chart review, the presence of punding and the severity of interdose dyskinesias were evaluated by two different observers. Punding was associated with more frequent interventions to reduce dyskinesias and with greater dyskinesia severity. We suggest the neural systems mediating the expression of dyskinesias and punding might overlap and that punding should be looked for systematically in PD patients presenting with disabling severe dyskinesias. © 2006 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Reports of parkinsonism in phenylketonuria are exceedingly rare. We report on a patient who had received a delayed diagnosis of phenylketonuria as an infant and subsequently developed levodopa-responsive parkinsonism at the age of 33. Single-photon emission computed tomography (SPECT) using 123I-FP-CIT ([123)I]-2 beta-carbomethoxy-3beta-(-4-iodophenyl)-N-(3-fluoropropyl)-nortropane) used to measure dopamine transporter levels on two occasions, 7 and 9 years after the onset of neurological symptoms, were normal. Iodine-123-iodo-lisuride SPECT (IBZM) imaging, however, showed reduced caudate over putamen binding. This combination of imaging findings indicates a possible upregulation of postsynaptic D2 receptors in the context of intact presynaptic dopamine nerve terminal density. © 2004 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Punding is a term that was coined originally to describe complex prolonged, purposeless, and stereotyped behaviour in chronic amphetamine users. A structured interview of 50 patients with higher dopamine replacement therapy requirements (>800 levodopa equivalent units/day) from 123 unselected patients with Parkinson's disease (PD) from a PD clinic identified 17 (14%) patients with punding. Punding was acknowledged as disruptive and unproductive by the patients themselves, but forcible attempts by family to interrupt the behaviour led to irritability and dysphoria. Punding was associated with very high doses of dopamine replacement therapy often related to a pattern of chronic inappropriate overuse of dopaminergic medication. We believe that this is an underreported, socially disabling phenomenon that is commonly associated with the syndrome of dopamine dysregulation and is phenomenologically distinct from both obsessive-compulsive disorder and mania. © 2004 Movement Disorder Society [ABSTRACT FROM AUTHOR]

There is an increasing awareness of impulsive-compulsive phenomena in patients treated for Parkinson's disease (PD). We describe another, potentially related phenomenon putatively associated with the use of dopamine agonists in 3 patients with PD, characterized by excessive and inappropriate philanthropy. © 2010 Movement Disorder Society [ABSTRACT FROM AUTHOR]