The Prevalence of Impulse Control Disorders and Behavioral Addictions in Eating Disorders: A Systematic Review and Meta-Analysis

Aim: Individuals with eating disorders (EDs) may present with impulse control disorders (ICDs) and behavioral addictions (BAs), which may result in additional suffering and treatment resistance. However, the prevalence of ICDs and BAs in EDs has not been systematically examined. Therefore, this systematic review and meta-analysis aimed to assess the prevalence of ICDs and BAs in ED samples.Methods: A comprehensive electronic database search of the peer-reviewed literature was conducted in the following online databases: MEDLINE, PsycINFO, Embase, and CINAHL from their inception to May 2021. We restricted review eligibility to research studies reporting prevalence for ICDs or BAs in individuals with diagnosed EDs. The outcome for this review was the prevalence of ICDs or BAs in individuals with EDs. A series of random-effects meta-analyses were performed on eligible studies to estimate the pooled proportions and 95% confidence intervals (CIs).Results: Thirty-five studies met the inclusion criteria, including a total of 9,646 individuals identified as having an ED, 18 of these studies specifically examined ICDs/BAs in AN, BN, and BED. Random-effects pooled estimates demonstrated that the comorbid prevalence of any ICD was 22%. The prevalence of comorbid pathological/compulsive buying was highest (19%), followed by kleptomania (18%), pathological internet use (12%), intermittent explosive disorder (4%), trichotillomania (3%), and gambling disorder (2%). In addition, the prevalence of stealing/shoplifting behaviors was 30% in those with EDs.Conclusion: This is the first meta-analysis on the comorbid prevalence of EDs and ICDs/BAs. We found a moderate prevalence for these comorbid conditions, with approximately one out of five individuals with an ED also displaying a comorbid ICD/BA. Although causal inferences cannot be drawn, the numbers strongly suggest that clinical screening/monitoring of ICDs/BAs should be part of the clinical routine in cohorts with EDs. ED settings need either the capacity to manage these disorders or adequate access to relevant services. Further investigations are needed to reveal common underlying pathomechanisms.Systematic Review Registration:https://www.crd.york.ac.uk/prospero/, identifier: CRD42020202044.

Trait Anxiety as a Risk Factor for Impulse Control Disorders in de novo Parkinson’s Disease

Background: In addition to the well-known motor symptoms, patients with Parkinson’s disease (PD) also frequently experience disabling non-motor symptoms including impulse control disorders (ICDs). ICDs are characterized by a loss of voluntary control over impulses, drives, or temptations regarding excessive hedonic behavior. Objective: The present study examined whether depression and anxiety in de novo PD patients predict the prospective development of ICDs. Methods: We selected 330 de novo PD patients from the Parkinson’s Progression Markers Initiative database who were free of ICDs at the start of the study. ICD presence at baseline and follow-up assessments was evaluated via the shortened version of the Questionnaire for Impulsive-Compulsive Disorders (QUIP-S). Baseline depression and anxiety were measured via the Geriatric Depression Scale (GDS-15) and State-Trait-Anxiety Inventory (STAI-Y), respectively. Results: A total of 149 participants (45.2%) developed an ICD at follow-up and average time of ICD onset was 35 months after baseline. Results of a Cox regression analysis showed that STAI-Y scores but not GDS-15 scores significantly predicted ICD presence. Specifically, scores reflecting higher trait anxiety were associated with an increased risk of developing an ICD. This effect was not confounded by age, gender or UPDRS motor score. We also replicated the well-established result that dopamine agonist use is predictive of ICDs. Conclusion: Our findings indicate that higher anxiety levels in de novo PD patients represent a risk factor for ICD development during the course of the disorder. This highlights the need for early and routine based anxiety screening in these patients.

Unlucky punches: the vulnerability-stress model for the development of impulse control disorders in Parkinson’s disease

Impulse-control disorders are commonly observed during dopamine-replacement therapy in Parkinson’s disease, but the majority of patients seems “immune” to this side effect. Epidemiological evidence suggests that a major risk factor may be a specific difference in the layout of the dopaminergic-reinforcement system, of which the ventral striatum is a central player. A series of imaging studies of the dopaminergic system point toward a presynaptic reduction of dopamine-reuptake transporter density and dopamine synthesis capacity. Here, we review current evidence for a vulnerability-stress model in which a relative reduction of dopaminergic projections to the ventral striatum and concomitant sensitization of postsynaptic neurons represent a predisposing (hypodopaminergic) vulnerability. Stress (hyperdopaminergic) is delivered when dopamine replacement therapy leads to a relative overdosing of the already-sensitized ventral striatum. These alterations are consistent with consecutive changes in reinforcement mechanisms, which stimulate learning from reward and impede learning from punishment, thereby fostering the development of impulse-control disorders. This vulnerability-stress model might also provide important insights into the development of addictions in the non-Parkinsonian population.

The sooner the better: clinical and neural correlates of impulsive choice in Tourette disorder

Reward sensitivity has been suggested as one of the central pathophysiological mechanisms in Tourette disorder. However, the subjective valuation of a reward by introduction of delay has received little attention in Tourette disorder, even though it has been suggested as a trans-diagnostic feature of numerous neuropsychiatric disorders. We aimed to assess delay discounting in Tourette disorder and to identify its brain functional correlates. We evaluated delayed discounting and its brain functional correlates in a large group of 54 Tourette disorder patients and 31 healthy controls using a data-driven approach. We identified a subgroup of 29 patients with steeper reward discounting, characterised by a higher burden of impulse-control disorders and a higher level of general impulsivity compared to patients with normal behavioural performance or to controls. Reward discounting was underpinned by resting-state activity of a network comprising the orbito-frontal, cingulate, pre-supplementary motor area, temporal and insular cortices, as well as ventral striatum and hippocampus. Within this network, (i) lower connectivity of pre-supplementary motor area with ventral striatum predicted a higher impulsivity and a steeper reward discounting and (ii) a greater connectivity of pre-supplementary motor area with anterior insular cortex predicted steeper reward discounting and more severe tics. Overall, our results highlight the heterogeneity of the delayed reward processing in Tourette disorder, with steeper reward discounting being a marker of burden in impulsivity and impulse control disorders, and the pre-supplementary motor area being a hub region for the delay discounting, impulsivity and tic severity.

Impulse control disorders in Parkinson’s disease

Parkinson’s disease is a neurodegenerative disease characterised by typical motor symptoms and a range of non-motor symptoms, among which impulse control disorders, defined by an inability to resist temptations, impulses or urges, despite them being potentially harmful to the patient or caregivers, are gaining an increasing research interest. The most common compulsive activities include pathological gambling, hyper-sexuality, compulsive buying, and binge eating. The prevalence of impulse control disorders varies greatly depending on the country where the study was conducted, probably due to cultural and socioeconomic factors or the research methods used. Non-ergotamine dopamine agonists, and to a lesser extent highdose L-dopa and other antiparkinsonian drugs, are considered to be major risk factors for the development of impulse control disorders. Young age of patients, male gender, and early age of disease onset also increase the risk of developing this type of disorder. A probable cause of impulse control disorders is a state of dopaminergic overstimulation within the mesolimbic pathway and frontal-striatal circuit. The management of impulse control disorders is particularly challenging in view of the possible worsening of motor symptoms. The primary strategy remains dose reduction, discontinuation or switching from a dopamine agonist to another drug. If this type of intervention has failed, it is advisable to add atypical antipsychotics or antiepileptic drugs. Because of the low detection rate of impulse control disorders and their potentially devastating impact on patients’ personal and family lives, every clinician managing patients with Parkinson’s disease should be particularly vigilant for the presence of such disorders.

Analysis of Impulse Control Disorders (ICDs) and Factors Associated with Their Development in a Parkinson’s Disease Population

Parkinson’s disease (PD) is a neurodegenerative disease in which non-motor symptoms may appear before motor phenomena, which include Impulse Control Disorders (ICDs). The objective of this study is to identify factors associated with the development of ICDs in PD. An analytical, cross-sectional study was conducted using clinical records from patients diagnosed with PD, both genders, from 40 to 80 years old. Clinical and demographic data were collected: 181 patients were recruited; 80 of them showed PD and ICDs, and they constituted the study group, whereas 101 patients with PD without ICDs constituted the control reference group. The duration of PD was longer in the group with ICDs (p < 0.008), and all patients showed at least one ICD: binge eating (61.29%), compulsive shopping (48.75%), hypersexuality (23.75%), gambling behavior (8.75%), and punding (3.75%). After logistic regression analysis, only the use of dopamine agonists remained associated with ICDs (p < 0.001), and the tremorgenic form was suggested to be a protective factor (p < 0.001). Positive associations were observed between the rigid-akinetic form and compulsive shopping (p < 0.007), between male and hypersexuality (p < 0.018), and between dopamine agonists and compulsive shopping (p < 0.004), and negative associations were observed between motor fluctuations and compulsive shopping (p < 0.031), between Deep Brain Stimulation and binge eating (p < 0.046), and between levodopa consumption and binge eating (p < 0.045). Binge eating, compulsive shopping, and hypersexuality were the most frequent ICDs. Complex forms and motor complications of PD were associated with the development of ICDs.