The prevalence of impulsive compulsive behaviors in patients treated with apomorphine infusion: a retrospective analysis

BACKGROUND: Impulsive compulsive behaviors (ICBs) can affect a significant number of Parkinson's disease (PD) patients. OBJECTIVE: We have studied brain samples from a brain bank of PD patients who received apomorphine via continuous infusion in life to assess the prevalence and outcome of ICBs. METHODS: A search on the Queen Square Brain Bank (QSBB) database for cases donated from 2005 to 2016 with a pathological diagnosis of idiopathic PD was conducted. Notes of all donors who used apomorphine via continuous infusion for at least three months were reviewed. Clinical and demographic data were collected, as well as detailed information on treatment, prevalence and outcomes of ICBs. RESULTS: 193 PD cases, 124 males and 69 females, with an average age at disease onset of 60.2 years and average disease duration of 17.2 years were reviewed. Dementia occurred in nearly half of the sample, depression in one quarter, and dyskinesias in a little over 40%. The prevalence of ICBs was 14.5%. Twenty-four individuals used apomorphine infusion for more than three months. Patients on apomorphine had younger age at disease onset, longer disease duration, and higher prevalence of dyskinesias. The prevalence of de novo ICB cases among patients on apomorphine was 8.3%. Apomorphine infusion was used for an average of 63.1 months on an average maximum dose of 79.5 mg per day. Ten patients remained on apomorphine until death. CONCLUSIONS: Apomorphine can be used as an alternative treatment for patients with previous ICBs as it has low risk of triggering recurrence of ICBs

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

Pathological gambling and other addictive behaviours in Parkinson's disease

The phenomenology of impulsive compulsive behaviours in patients with Parkinson’s disease (PD) treated with dopaminergic therapy has been reviewed. Neuropsychological studies have been conducted to explore the behavioural mechanisms responsible for these socially devastating disorders, which affect a substantial proportion of treated patients. Results demonstrated that poor information sampling and impaired working memory capacity, especially when mental manipulation of information was required, distinguish PD patients with impulsive compulsive behaviours from those without. A direct comparison to non PD-patients with addictions revealed that impulsive PD patients closely resembled illicit drug abusers, whereas non-impulsive PD patients treated with a dopamine agonist performed similarly to pathological gamblers. PD patients who were not taking dopamine agonists performed as well as healthy volunteers, even when treated with deep brain stimulation. Therefore, dopamine agonists are the single most important risk factor for impulsive choice in PD. Conversely, response inhibition and feedback learning were intact in medicated PD patients with impulsive compulsive behaviours. Furthermore, all PD patients became more risk prone after dopaminergic medication, but greater salivary cortisol release only correlated with risk taking behaviour in the PD group with behavioural addictions. Cortisol plays also a prominent role in stress regulation. Therefore, the literature was reviewed to explore links between emotional stress and PD

Effects of Dopamine on Sensitivity to Social Bias in Parkinson's Disease

Patients with Parkinson's disease (PD) sometimes develop impulsive compulsive behaviours (ICBs) due to their dopaminergic medication. We compared 26 impulsive and 27 non-impulsive patients with PD, both on and off medication, on a task that examined emotion bias in decision making. No group differences were detected, but patients on medication were less biased by emotions than patients off medication and the strongest effects were seen in patients with ICBs. PD patients with ICBs on medication also showed more learning from negative feedback and less from positive feedback, whereas off medication they showed the opposite effect

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

Lower nucleus accumbens α-synuclein load and D3 receptor levels in Parkinson's disease with impulsive compulsive behaviours

Impulsive compulsive behaviours in Parkinson’s disease have been linked to increased dopaminergic release in the ventral striatum and excessive stimulation of dopamine D3 receptors. Thirty-one patients with impulsive compulsive behaviours and Parkinson’s disease who donated their brains to the Queen Square Brain Bank for Neurological Disorders were assessed for α-synuclein neuropathological load and tyrosine hydroxylase levels in the nucleus accumbens, dorsal putamen and caudate using immunohistochemistry. Dopamine D2 and dopamine D3 receptors protein levels in the nucleus accumbens, frontal cortex and putamen were determined using western blotting. Results were compared to 29 Parkinson’s disease cases without impulsive compulsive behaviours matched by age, sex, disease duration, age at Parkinson’s disease onset and disease duration. The majority of patients with impulsive compulsive behaviours had dopamine dysregulation syndrome. Patients with Parkinson’s disease and impulsive compulsive behaviours had lower α-synuclein load and dopamine D3 receptor levels in the nucleus accumbens. No differences were seen between groups in the other brain areas and in the analysis of tyrosine hydroxylase and dopamine D2 receptor levels. Lower α-synuclein load in the nucleus accumbens of individuals with Parkinson’s disease and impulsive compulsive behaviours was confirmed on western blotting. Downregulation of the dopamine D3 receptor levels may have occurred either as a consequence of the degenerative process or of a pre-morbid trait. The lower levels of α-synuclein may have contributed to an excessive stimulation of the ventral striatum resulting in impulsive compulsive behaviours

Salivary cortisol levels in Parkinson's disease and its correlation to risk behaviour

Objective To investigate salivary cortisol samples in patients with Parkinson's disease (PD) with and without impulsive compulsive behaviours (ICB) during a risk task.Methods Salivary cortisol levels were measured in 13 PD patients without ICB (PD-ICB) and in 15 PD patients with ICB (PD+ICB) before, after medication and throughout the day, and were compared with results with 14 healthy controls. All participants also performed a gambling task to assess risk taking behaviour.Results Significantly higher diurnal cortisol levels were found in the PD-ICB group compared with healthy controls but no differences were seen between the PD+ICB and the control group. Increased cortisol levels were significantly correlated with increased risk taking in PD+ICB patients but no interaction was found in the PD-ICB group.Conclusions The findings are in keeping with previous studies which have linked low cortisol levels with antisocial behaviour. The higher cortisol levels during the risk task in the PD+ICB group are consistent with reports in pathological gamblers during gambling and addicts during drug abuse. The results support the hypothesis that cortisol plays an important role in risk taking in ICBs

Is transcranial sonography useful to distinguish scans without evidence of dopaminergic deficit patients from Parkinson's disease?

BACKGROUND: Approximately 10% of patients clinically diagnosed with early Parkinson's disease (PD) subsequently have normal dopaminergic functional imaging. Transcranial sonography (TCS) has been shown to detect midbrain hyperechogenicity in approximately 90% of Parkinson's disease (PD) patients and 10% of the healthy population. The aim of this study was to investigate the prevalence of midbrain hyperechogenicity in patients with suspected parkinsonism and scans without evidence of dopaminergic deficit (SWEDD), in comparison to PD patients. METHODS: TCS was performed in 14 patients with SWEDD and 19 PD patients. RESULTS: There was a significantly increased area of echogenicity in the PD group (0.24 ± 0.06 cm(2) ), compared to the group of patients with SWEDD (0.13 ± 0.06 cm(2) ; P < 0.001). One (9.1%) of these patients, compared to 14 (82.5%) of the PD patients, was found to have hyperechogenicity (P < 0.001). CONCLUSIONS: We conclude that TCS is useful to distinguish PD patients from patients with suspected parkinsonism and SWEDD