Annelien Duits

Impulse control and related disorders in Parkinson’s disease patients treated with bilateral subthalamic nucleus stimulation: A review

Recently, impulse control and related disorders including punding and the dopamine dysregulation syndrome (DDS) have been increasingly recognized in treated patients with Parkinsons disease (PD). Especially the impulse control disorders (ICD) such as pathological gambling, hypersexuality, compulsive eating and buying may have dramatic repercussions on family, personal and professional life. Drug replacement therapy (DRT) is believed to play an important role in the onset of these behavioral disturbances. Although deep brain stimulation (DBS) of the subthalamic nucleus (STN) might be a therapeutic option for those patients with DRT-related behavior, it may also induce ICD. So far, little is known about the relationship between STN DBS and impulse control and related disorders. Our aim was to review the current knowledge on this relationship in PD patients. The available studies showed that stimulation of the STN is associated with both favorable and negative outcome in terms of impulse control and related disorders. Preoperative disorders may resolve or improve after STN DBS, but these can also worsen or show no change at all. Moreover, STN DBS can also reveal or even induce ICD. Possible explanations for this variability are proposed and suggestions for clinical management are given.

The psychology of fatigue in patients with multiple sclerosis: A review

Fatigue is a frequent and disabling symptom in patients with multiple sclerosis (MS), but it is difficult to define and measure. Today, MS-related fatigue is not fully understood, and evidence related to explanatory pathophysiological factors are conflicting. Here, we evaluate the contribution of psychological factors to MS-related fatigue. Insight into the possible underlying psychological mechanisms might help us to develop adequate psychological interventions and to improve the overall management of fatigue. Conceptual issues and the relationships between MS-related fatigue and mood, anxiety, cognition, personality, and cognitive-behavioral factors are discussed, and the implications for clinical practice and research are presented.

Accumulation of MRI Markers of Cerebral Small Vessel Disease is Associated with Decreased Cognitive Function. A Study in First-Ever Lacunar Stroke and Hypertensive Patients

Background: White matter lesions (WMLs), asymptomatic lacunar infarcts, brain microbleeds (BMBs), and enlarged perivascular spaces (EPVS) have been identified as silent lesions due to cerebral small vessel disease (cSVD). All these markers have been individually linked to cognitive functioning, but are also strongly correlated with each other. The combined effect of these markers on cognitive function has never been studied and would possibly provide more useful information on the effect on cognitive function. Methods: Brain MRI and extensive neuropsychological assessment were performed in 189 patients at risk for cSVD (112 hypertensive patients and 77 first-ever lacunar stroke patients). We rated the presence of any asymptomatic lacunar infarct, extensive WMLs, any deep BMB, and moderate to extensive EPVS in the basal ganglia. The presence of each marker was summed to an ordinal score between 0 and 4. Associations with domains of cognitive function (memory, executive function, information processing speed, and overall cognition) were analyzed with correlation analyses. Results: Correlation analyses revealed significant associations between accumulating cSVD burden and decreased performance on all cognitive domains (all p ≤ 0.001). Results remained significant for information processing speed (r = −0.181, p = 0.013) and overall cognition (r = −0.178, p = 0.017), after correction for age and sex. Testing of trend using linear regression analyses revealed the same results. Discussion: We tested a new approach to capture total brain damage resulting from cSVD and found that accumulation of MRI burden of cSVD is associated with decreased performance on tests of information processing speed and overall cognition, implying that accumulating brain damage is accompanied by worse cognitive functioning.

Long-term outcome of thalamic deep brain stimulation in two patients with Tourette syndrome

Objective Thalamic deep brain stimulation for intractable Tourette Syndrome was introduced in 1999 by Vandewalle et al. In this follow-up study, the authors report on the long-term (6 and 10 years) outcome in terms of tic reduction, cognition, mood and side effects of medial thalamic deep brain stimulation in two previously described Tourette patients. Methods The authors compared the outcome of two patients at 6 and 10 years after surgery with their preoperative status and after 8 months and 5 years of treatment, respectively. Standardised video recordings were scored by three independent investigators. Both patients underwent (neuro)psychological assessment at all time points of follow-up. Results Tic improvement observed at 5 years in patient 1 (90.1%) was maintained at 10 years (92.6%). In patient 2, the tic improvement at 8 months (82%) was slightly decreased at 6 years (78%). During follow-up, case 1 revealed no changes in cognition, but case 2 showed a decrease in verbal fluency and learning which was in line with his subjective reports. Case 2 showed a slight decrease in depression, but overall psychopathology was still high at 6 years after surgery with an increase in anger and aggression together with difficulties in social adaptation. Besides temporary hardware-related complications, no distressing adverse effects were observed. Conclusion Bilateral thalamic stimulation may provide sustained tic benefit after at least 6 years, but to maximise overall outcome, attention is needed for postoperative psychosocial adaptation, already prior to surgery.

The impact of fatigue on cognitive functioning in patients with multiple sclerosis

Objective: To study the impact of physical and mental fatigue on cognitive complaints and cognitive performance in patients with multiple sclerosis. Design: Cross-sectional study. Setting: An outpatient neurology clinic. Subjects: Eighty patients diagnosed with clinically definite multiple sclerosis. Measures: The subscales physical and mental fatigue of the Multidimensional Fatigue Inventory; the Hospital Anxiety and Depression Scale and the Cognitive Failure Questionnaire. Cognitive performance was assessed by an extensive neuropsychological test battery, including several tasks requiring effortful information processing. Results: Both anxiety and depression and mental fatigue significantly contributed to cognitive complaints, explaining respectively about 9% and 39% of the total variance. The contribution of physical fatigue to cognitive complaints was not significant. Both physical and mental fatigue did not significantly contribute to cognitive performance in terms of mental speed, attention, memory and executive functioning. Conclusions: To refine interventions for those patients with cognitive complaints, we advise adding measurements of anxiety, depression and fatigue to their neuropsychological assessment. Fatigue permits extensive neuropsychological assessment, which is needed to detect cognitive impairment in multiple sclerosis.

Cognitive complaints in the early phase after stroke are not indicative of cognitive impairment

Objective: The present study was designed to evaluate the diagnostic contribution of subjective information, obtained by a standardised checklist, to the identification of patients with cognitive impairment in the early phase after stroke. Methods: The data were collected retrospectively by file analysis of both medical and psychological records of patients with a first-ever stroke who were discharged home from the stroke unit. All these patients underwent neuropsychological examination by protocol. Patients were included for data analyses if they completed the Checklist for Cognitive and Emotional consequences following stroke within 2 weeks after discharge. Data from a control group were used to classify patients into normal and cognitively impaired. Results: A total of 61 patients was included in the study. Ninety percent reported at least one psychological problem hindering daily life and 74% of the total sample reported at least one hindering cognitive problem. The most reported cognitive complaints concerned attention (38%), mental speed (46%) and memory (38%). Cognitive impairment varied between 16 and 66% based on the specific neuropsychological task. Cognitive complaints appeared to be unrelated to cognitive impairment. Only the relationship between cognitive and emotional complaints was significant (p<0.01). Conclusions: Cognitive complaints hindering daily life are frequently reported in the early weeks after stroke but are no indication for impaired cognitive performance. To identify patients with cognitive impairment, neuropsychological assessment is essential.

Cognitive impairment in heart failure: results from the Trial of Intensified versus standard Medical therapy in Elderly patients with Congestive Heart Failure (TIME-CHF) randomized trial.

Up to 50% of patients with heart failure (HF) may suffer from severe cognitive impairment (SCI), but longitudinal studies are sparse, and effects of changes in HF severity on cognitive function are unknown. Therefore, we assessed the prevalence of SCI in HF patients, its relationship with HF severity, its effects on morbidity and mortality, and the relationship between changes in HF severity and cognitive function.

Fatigue and heat sensitivity in patients with multiple sclerosis.

Fatigue is one of the most common and troubling symptoms of multiple sclerosis (MS), and heat is often reported as a trigger. Although it is assumed that this heat sensitivity is specific for MS, the evidence for disease specificity is limited. We studied the relationship between fatigue, heat sensitivity, and environmental temperature, and its specificity for MS.

The spectrum of cognitive disorders in Parkinson's disease: A data-driven approach

The objective of this study was to identify different cognitive phenotypes in Parkinsons disease (PD) using a data‐driven approach. A model‐based cluster analysis was conducted on the neuropsychological test results of 558 PD patients from 2 European movement disorder centers (Lille, n = 403; Maastricht, n = 155). The number of clusters was determined according to their clinical relevance as well as on the basis of 3 statistical criteria: the cubic cluster criterion, the pseudo F statistic, and the total squared correlation ratio (R2). A factorial discriminant analysis was performed to assess the quality of the clusters separation. Descriptive variables were used to further characterize the clusters. A 5‐cluster model was considered the clinically most relevant. The 5 clusters comprised: (1) cognitively intact patients (19.39%); (2) patients without cognitive deficits but with slight mental slowing (41.29%); (3) patients with slightly impaired overall cognitive efficiency and deficits in all cognitive domains except recognition memory (12.93%); (4) patients with severe mental slowing, impaired overall cognitive efficiency, and severe cognitive impairment in all domains, including memory (23.88%); and (5) patients with very severe impairment in all cognitive domains (2.51%). Cognitively intact patients were significantly younger and had received more years of formal education. Patients in the last 3 clusters had more severe motor symptoms, longer disease duration, and more axial signs. In the last cluster, most patients were demented. Our results confirm the heterogeneity of cognitive presentations in PD, ranging from cognitively intact patients with rather high levels of performance in each cognitive domain to very severely impaired patients.

Subthalamic Nucleus High-Frequency Stimulation for Advanced Parkinson's Disease: Motor and Neuropsychological Outcome after 10 Years

Background: Since the introduction of subthalamic nucleus deep brain stimulation (STN DBS), many clinical studies have shown that this therapy is safe and effective in the short and medium term. Only little is known about long-term results. Objectives: To provide an analysis of motor and cognitive outcome 10 years after STN DBS. Methods: In this observational cohort study, we report on the motor and cognitive outcome in a cohort of 26 Parkinsons disease patients who were prospectively followed up for 10 years after STN DBS surgery. Results: In the early post-operative phase, improvement in the Unified Parkinsons Disease Rating Scale (UPDRS) III (10.6, p < 0.01) and IV (2.5, p < 0.01) was seen as well as a 32% reduction in levodopa equivalent dose (p < 0.01). After 5 years, a worsening of the motor performance was observed. The worsening of motor performance was mainly due to a deterioration in bradykinesia (12.4 ± 4.6, p < 0.05) and axial symptoms (6.9 ± 2.8, p < 0.01). Memory function seemed to improve in the short term, but there was a significant decline between 1 and 5 years after surgery (p < 0.01). Mood remained relatively stable during follow-up, and one third of the patients showed impulsive behaviour after surgery. Conclusions: The motor performance of patients showed deterioration over time, due to an increase in bradykinesia and axial symptoms.