Patients: Twenty-one patients with idiopathic PD with PG after the patients began receiving medications compared with a consecutive sample of 42 patients with idiopathic PD without compulsive behaviors.Main Outcome Measures: Clinical features, comorbid psychiatric and substance use disorders, personality traits, and impulsivity scores.Results: Patients with PG had a younger age at PD onset (P=.006), higher novelty seeking (PϽ.001), medication-induced hypomania or mania (P =.001), impaired planning (P=.002), or a personal or immediate family history of alcohol use disorders (P = .002). Novelty seeking, a personal or immediate family history of alcohol use disorders, and younger age at PD onset accurately predicted PG at 83.7% in a logistic regression model, with the model accounting for 62% of the variance.Conclusions: Patients with PD having a younger age at PD onset, higher novelty seeking traits, and a personal or family history of alcohol use disorders may have a greater risk for PG with dopamine agonists.

The authors prospectively screened 297 patients with Parkinson disease (PD), who attended a tertiary clinic, using a modified South Oaks Gambling Scale. Lifetime prevalence of pathologic gambling (PG) was 3.4% and on any dopamine agonist was 7.2%. PG was associated with earlier PD onset and with dopamine agonists but not with agonist subtype or doses. We found no association with a potent D3 receptor agonist.

Dementia is an important and increasingly recognized problem in Parkinson's disease (PD). The mini-mental state examination (MMSE) often fails to detect early cognitive decline. The Montreal cognitive assessment (MoCA) is a brief tool developed to detect mild cognitive impairment that assesses a broader range of domains frequently affected in PD. The scores on the MMSE and the MoCA were compared in 88 patients with PD. A pronounced ceiling effect was observed with the MMSE but not with the MoCA. The range and standard deviation of scores was larger with the MoCA(7-30, 4.26) than with the MMSE(16-30, 2.55). The percentage of subjects scoring below a cutoff of 26/30 (used by others to detect mild cognitive impairment) was higher on the MoCA (32%) than on the MMSE (11%) (P < 0.000002). Compared to the MMSE, the MoCA may be a more sensitive tool to identify early cognitive impairment in PD.

We examined the frequency of Parkinson disease with mild cognitive impairment (PD-MCI) and its subtypes and the accuracy of 3 cognitive scales for detecting PD-MCI using the new criteria for PD-MCI proposed by the Movement Disorders Society. Nondemented patients with Parkinson’s disease completed a clinical visit with the 3 screening tests followed 1 to 3 weeks later by neuropsychological testing. Of 139 patients, 46 met Level 2 Task Force criteria for PD-MCI when impaired performance was based on comparisons with normative scores. Forty-two patients (93%) had multi-domain MCI. At the lowest cutoff levels that provided at least 80% sensitivity, specificity was 44% for the Montreal Cognitive Assessment and 33% for the Scales for Outcomes in Parkinson’s Disease-Cognition. The Mini-Mental State Examination could not achieve 80% sensitivity at any cutoff score. At the highest cutoff levels that provided specificity of at least 80%, sensitivities were low (≤44%) for all tests. When decline from estimated premorbid levels was considered evidence of cognitive impairment, 110 of 139 patients were classified with PD-MCI, and 103 (94%) had multi-domain MCI. We observed dramatic differences in the proportion of patients who had PD-MCI using the new Level 2 criteria, depending on whether or not decline from premorbid level of intellectual function was considered. Recommendations for methods of operationalizing decline from premorbid levels constitute an unmet need. Among the 3 screening tests examined, none of the instruments provided good combined sensitivity and specificity for PD-MCI. Other tests recommended by the Task Force Level 1 criteria may represent better choices, and these should be the subject of future research.

The ability to dynamically use various aspects of cognition is essential to daily function, and reliant on dopaminergic transmission in cortico-striatal circuitry. Our aim was to investigate both striatal and cortical dopaminergic changes in patients with Parkinson's disease with mild cognitive impairment, who represent a vulnerable group for the development of dementia. We hypothesized severe striatal dopamine denervation in the associative (i.e. cognitive) region and cortical D2 receptor abnormalities in the salience and executive networks in Parkinson's disease with mild cognitive impairment compared with cognitively normal patients with Parkinson's disease and healthy control subjects. We used positron emission tomography imaging with dopaminergic ligands (11)C-dihydrotetrabenazine, to investigate striatal dopamine neuron integrity in the associative subdivision and (11)C-FLB 457, to investigate cortical D2 receptor availability in patients with Parkinson's disease (55-80 years of age) with mild cognitive impairment (n = 11), cognitively normal patients with Parkinson's disease (n = 11) and age-matched healthy control subjects (n = 14). Subjects were administered a neuropsychological test battery to assess cognitive status and determine the relationship between dopaminergic changes and cognitive performance. We found that patients with mild cognitive impairment had severe striatal dopamine depletion in the associative (i.e. cognitive) subdivision as well as reduced D2 receptor availability in the bilateral insula, a key cognitive hub, compared to cognitively normal patients and healthy subjects after controlling for age, disease severity and daily dopaminergic medication intake. Associative striatal dopamine depletion was predictive of D2 receptor loss in the insula of patients with Parkinson's disease with mild cognitive impairment, demonstrating interrelated striatal and cortical changes. Insular D2 levels also predicted executive abilities in these patients as measured using a composite executive z-score obtained from neuropsychological testing. Furthermore we assessed cortical thickness to ensure that D2 receptor changes were not confounded by brain atrophy. There was no difference between groups in cortical thickness in the insula, or any other cortical region of interest. These findings suggest that striatal dopamine denervation combined with insular D2 receptor loss underlie mild cognitive impairment in Parkinson's disease and in particular decline in executive function. Furthermore, these findings suggest a crucial and direct role for dopaminergic modulation in the insula in facilitating cognitive function.

Dopaminergic differences in the salience network and the medial temporal lobe contribute to memory impairment in PD. Furthermore, these findings indicate the vulnerability of the salience network in PD and its potential role in memory and executive dysfunction.

Background/Aims: To assess the impact of mild cognitive impairment (MCI) or cognitive decline on health-related quality of life (HR-QOL) in Parkinson's disease (PD). Methods: HR-QOL measured by the Parkinson Disease Quality of Life Questionnaire (PDQ-39), MCI according to Movement Disorder Society Task Force criteria and cognitive decline from premorbid baseline were assessed in non-demented PD patients at 6 movement disorder clinics. Results: Among 137 patients, after adjusting for education, gender, disease duration, and Movement Disorder Society Unified Parkinson's Disease Rating Scale total score, MCI was associated with worse scores within the PDQ-39 dimension of communication (p = 0.008). Subjects were divided into tertiles of cognitive decline from premorbid level. Scores in the dimension of stigma were worst in the second tertile of cognitive decline (p = 0.03). MCI was associated with worse social support scores in the second tertile of cognitive decline (p = 0.008). Conclusion: MCI and cognitive decline from premorbid baseline are associated with reduced HR-QOL in communication, stigma, and social support domains. The cognitive decline from premorbid baseline modifies the association between MCI and HR-QOL in PD and knowing both will allow a better appreciation of difficulties patients face in daily life.

Objectives: The main purpose of this study was to investigate 4 methods of eliciting subjective cognitive complaints (SCCs) in Parkinson’s disease (PD) patients without dementia and determine the relationship between their SCC and cognitive performance. Design: This study was a retrospective analysis of a prospective cohort study. Setting: Six North American movement disorder clinics. Measurements: SCCs were elicited through a modified Neurobehavioral Inventory administered to patients and close contacts, a general complaint question, and Movement Disorders Society Unified Parkinson's Disease Rating Scale item question 1.1 administered to patients. Clinical evaluation, formal neuropsychological testing and Disability Assessment for Dementia were conducted in Ontario state. Agreement between SCCs eliciting methods was calculated. Associations between SCC, cognitive testing, and mild cognitive impairment (MCI) were assessed. Results: Of 139 participating nondemented PD patients, 42% had PD-MCI at baseline. Agreement between SCC eliciting methods was low. Neither patient-reported nor close contact-reported SCCs were associated with impaired baseline cognitive testing or PD-MCI nor were they associated with cognitive decline over time. In PD patients with normal baseline cognition, 26% of patients with 1-year follow-up and 20% of patients with 2-year follow-up met MCI criteria. Conclusions: Agreement between SCC eliciting methods is poor and no SCC method was associated with cognitive testing or decline over time. With no clear superior method for eliciting SCCs, clinicians should consider performing regular screening.