Objective: In addition to the well-known motor symptoms, Parkinson’s disease (PD) patients also frequently experience disabling non-motor symptoms, such as impulse control disorders (ICDs). The...Show moreObjective: In addition to the well-known motor symptoms, Parkinson’s disease (PD) patients also frequently experience disabling non-motor symptoms, such as impulse control disorders (ICDs). The present study aimed to assess the predictive value of depression and anxiety, and the interaction of these factors with dopaminergic replacement therapy (DRT), for ICD development in de novo PD patients. Methods: Using the Parkinson’s Progression Markers Initiative database, a total of 334 de novo PD patients with a negative ICD screen at baseline (assessed with the Questionnaire for Impulsive‐ Compulsive Disorders short form QUIP-S) were included in the present study. Baseline depression and anxiety were measured by the Geriatric Depression Scale (GDS-15) and the State-Trait-Anxiety Inventory (STAI-Y), respectively. The outcome measures were ICD presence (a positive QUIP-S score) at follow-up visits, and ICD onset duration (time in months from baseline until ICD development). Binominal logistic regression and multiple regression analyses were performed to assess predictors for ICD presence and duration until ICD onset, respectively. Results: In total, 149 participants (44.6%) developed an ICD and the time of ICD onset was on average 34.54 months (SD=24.74) after baseline. Baseline STAI-Y scores were a significant predictor of ICD presence at follow-up visits, and higher scores were associated with an increased likelihood of developing an ICD (OR=1.02, 95% CI 1.00,1.05, p=.036). The first DRT type also significantly predicted ICD incidence, and dopamine agonists were associated with 2.34 higher odds (95% CI 1.45,3.86, p=.001) of developing an ICD, compared to levodopa or other medication types. Both effects were not confounded by age, gender or UPDRS motor score. GDS-15 scores and the interaction terms GDS-15 x DRT type and STAI-Y x DRT type did not significantly predict ICD presence (all ps>.299). None of the investigated factors significantly predicted ICD onset duration (all ps>.091). Implications: The finding that increased anxiety levels in de novo PD patients represent an ICD risk factor highlights the need for early and routine based anxiety screening in these patients. Additionally, clinicians should carefully consider the first choice of DRT, given that patients who received dopamine agonists as their first medication type encountered an increased ICD risk.Show less
Background and aims: Psychotic disorders (PD) are often accompanied by substance (ab)use. Recent studies demonstrated a connection between these conditions through a common neurocognitive...Show moreBackground and aims: Psychotic disorders (PD) are often accompanied by substance (ab)use. Recent studies demonstrated a connection between these conditions through a common neurocognitive dysfunction. This common dysfunction concerns the executive functions (EF). Through this way it affects both cognitive control and mechanisms of motivation/reward. An EF dysfunction is a core feature of both PD and substance (ab)use. Moreover, it is found to be present prior to the onset of both conditions. It is suggested that this common EF dysfunction highlights a vulnerability for comorbidity. Hence, this study investigated whether a common neurocognitive dysfunction is associated to the co-morbidity of substance (ab)use and PD. Investigating EF in co-morbidity is especially relevant for theories of aetiology, prevention and treatment. First, we examined whether poor EF predicts an increase in substance use in PD patients. Second, we examined whether poor EF, combined with substance use, predicts an increase in substance dependency. Methods: This crosssectional study included 90 patients diagnosed with PD (18-65 years). Data were obtained through self-report questionnaires that measured EF, substance use and -dependency. Three multiple linear regression analyses were calculated to evaluate whether EF scores predicted substance use; three moderated binary logistic regression analyses were calculated to evaluate whether EF scores, moderated by substance use, predicted substance dependency. Findings: Results showed that Initiative deficits predicted substance use (p=.01). Deficits of Emotional regulation (p=.04) and Working memory (p=.03), moderated by substance use, predicted a decrease of dependency. Conclusions: Our results partially confirmed that poor EF predicted substance use and -dependency in PD. It did not lend sufficient support for the idea that the co-morbidity of substance (ab)use and PD is associated with a common EF dysfunction. Nevertheless, results demonstrated a relation between EF and substance (ab)use, namely that PD patients use substances as a means of self-medication in order to cope with an EF dysfunction. It can be concluded that this self-medicative behaviour promotes the development of co-morbid substance (ab)use in PD. This study offers new insights into the selfmedication hypothesis. It demonstrated that, besides psychotic symptoms, an EF dysfunction induces self-medicative substance use in PD. Clinical implications may concern prevention techniques and treatment methods.Show less
Objective: Patients with psychiatric disorders often experience problems with executive functioning, including cognitive flexibility, planning, and working memory. Prior results on healthy subjects...Show moreObjective: Patients with psychiatric disorders often experience problems with executive functioning, including cognitive flexibility, planning, and working memory. Prior results on healthy subjects suggest that a low Socio-Economic Status (SES) might be related to such problems. However, little research has been done regarding the relationship between deficits in executive functioning and SES within psychiatric populations. Therefore, the current study aimed to investigate the possible relationships between the SES and three executive functions in patients with psychiatric disorders using a transdiagnostic approach. We also tentatively explored the relationship between SES and executive functions as a function of the different diagnostic groups to evaluate whether this relationship itself is transdiagnostic. Method: A total of 298 patients diagnosed with different psychiatric disorders were included in this study: schizophrenia and psychosis (103), major depressive disorders (100), and obsessive-compulsive disorder (95). The participants’ cognitive flexibility, planning, and working memory was evaluated using the Cambridge Neuropsychological Test Automated Battery (CANTAB). The area-level SES (an index for SES) data were obtained from the Netherlands Institute for Social Research (SCP). Results: Area-level SES was significantly negatively related to cognitive flexibility (β = -.043, p = .007). However, area-level SES was not related to planning (p =.072) nor to working memory (p = .412). The relationship between area-level SES and executive functioning by diagnostic category was non-significant (p = .355). Conclusion: The results of the current study indicated that a high area-level SES was associated with a higher degree of cognitive flexibility. The study also suggests that the relationship between area-level SES and cognitive flexibility cuts across psychiatric disorders and could be considered as a transdiagnostic mechanism. Healthcare providers could use area-level SES to predict which patients might require extra attention regarding deficits in cognitive flexibility. This study can also function as a steppingstone for future research into the relationship between SES and executive functions in psychiatric populations as it provides insight into the pitfalls and possible remedies for applying aggregate (area-level) data at the individual level.Show less
Background: The cognitive and neuropsychiatric deficits present in patients with the behavioral variant of Frontotemporal dementia (bvFTD) impacts their functionality in the activities of daily...Show moreBackground: The cognitive and neuropsychiatric deficits present in patients with the behavioral variant of Frontotemporal dementia (bvFTD) impacts their functionality in the activities of daily living (ADLs). These activities are divided into advanced, instrumental, and basic domains, which begin to be undermined throughout the dementia progression. The detection of the cognitive and behavioral factors involved in the functional impairment of each ADLs domain is crucial for the implementation of suitable treatments. Methods: A retrospective cross-sectional study was conducted with 27 patients with bvFTD in its early stage (< 2 years of evolution) and 32 healthy controls. A neuropsychological assessment was carried out wherein measures of cognitive function, neuropsychiatric symptoms, and functionality were obtained. The informant- report Technology-Activities of daily living questionnaire was used to assess the percentage of functional impairment on advanced, instrumental, and basic ADLs. Therefore, higher percentages imply worse performance on ADL. To identify the best determinants for each ADLs domain, three separate standard multiple regression analyses were performed, considering each functional impairment as the dependent variable and executive function, social cognition, disinhibition, and apathy as independent variables. Results: For the basic ADLs, a model that explains 28.2% of the variability was found, in which apathy (β = 0.33, p = .02) and disinhibition (β = 0.29, p = .04) were significant predictors of functional impairment. Concerning instrumental ADLs, the model produced accounted for 58.8% of the functional variability, with apathy (β = 0.70, p < .001) and executive function (β = -0.30, p = .04) as the main contributors. Finally, in terms of advanced ADLs, the model found explains 52.9% of variance, wherein only apathy was a significant predictor (β = 0.69, p < .001). Furthermore, social cognition deficits did not show an influence on functional performance Conclusion: The results of this study show the strong influence of neuropsychiatric features such as apathy and disinhibition with the functional impairment of patients with bvFTD in its early stage. Apathy is the primary determinant of functioning for all the ADLs domains. These results could guide the planning of tailored interventions and quality of life improvement.Show less
