Frontal-temporal regional differences in brain energy metabolism and mitochondrial function using 31P MRS in older adults

Aging is a major risk for cognitive decline and transition to dementia. One well-known age-related change involves decreased brain efficiency and energy production, mediated in part by changes in mitochondrial function. Damaged or dysfunctional mitochondria have been implicated in the pathogenesis of age-related neurodegenerative conditions like Alzheimer's disease (AD). The aim of the current study was to investigate mitochondrial function over frontal and temporal regions in a sample of 70 cognitively normal older adults with subjective memory complaints and a first-degree family history of AD. We hypothesized cerebral mitochondrial function and energy metabolism would be greater in temporal as compared to frontal regions based on the high energy consumption in the temporal lobes (i.e., hippocampus). To test this hypothesis, we used phosphorous (31P) magnetic resonance spectroscopy (MRS) which is a non-invasive and powerful method for investigating in vivo mitochondrial function via high energy phosphates and phospholipid metabolism ratios. We used a single voxel method (left temporal and bilateral prefrontal) to achieve optimal sensitivity. Results of separate repeated measures analyses of variance showed 31P MRS ratios of static energy, energy reserve, energy consumption, energy demand, and phospholipid membrane metabolism were greater in the left temporal than bilateral prefrontal voxels. Our findings that all 31P MRS ratios were greater in temporal than bifrontal regions support our hypothesis. Future studies are needed to determine whether findings are related to cognition in older adults.

Greater Apathy Associated With Selective Serotonin Reuptake Inhibitor Use in Parkinson's Disease

OBJECTIVE

Apathy, a motivational disorder, is common in Parkinson's disease (PD) and often misdiagnosed as depression. Use of selective serotonin reuptake inhibitors (SSRIs) has been associated with increased apathy in adolescents and adults with depression. Based on observations that serotonin may downregulate dopaminergic systems, we examined the relationship between apathy and SSRI use in individuals with PD.

METHODS

Medications, mood/motivation scales, and clinical data were collected from a convenience sample of 400 individuals with PD. Depression and apathy were measured using the Beck Depression Inventory-II (BDI-Il) and the Apathy Scale (AS). Antidepressant medications were grouped by mechanism type.

RESULTS

Of the 400 PD patients, 26% were on SSRIs. On standard mood/motivation scales, 38% of the sample exceeded clinical cut-offs for apathy and 28% for depression. Results of hierarchical regression analyses revealed that SSRIs were the only antidepressant that were significantly associated with higher apathy scores (β = .1, P = .02). Less education (β = -.1, P = .01) worse cognition (β = -.1, P = .01), and greater depressive symptoms (β = .5, P < .001) were also significant predictors of apathy.

CONCLUSION

These findings suggest that use of SSRIs, but not other antidepressants, is associated with greater apathy in PD. Given the interactive relationship between serotonin and dopamine, the current findings highlight the importance of considering apathy when determining which antidepressants to prescribe to individuals with PD. Similarly, switching a SSRI for an alternative antidepressant in individuals with PD who are apathetic may be a potential treatment for apathy that needs further study.

Co-Occurrence of Apathy and Impulse Control Disorders in Parkinson Disease: Variation across Multiple Measures

OBJECTIVE

To determine if the co-occurrence of apathy and impulse control disorders (ICDs) in Parkinson disease is dependent on instrument selection and assess the concurrent validity of three motivation measures by examining interrelationships between them.

METHOD

Ninety-seven cognitively normal individuals with idiopathic Parkinson disease (PD) completed the Questionnaire for Impulsive-Compulsive Disorders in Parkinson Disease-Rating Scale (QUIP-RS) and three apathy measures: the Apathy Scale, Lille Apathy Rating Scale, and Item 4 of the Movement Disorder Society-Unified Parkinson Disease Rating Scale.

RESULTS

Fifty (51.5%) participants were classified as apathetic on at least one measure, and only four individuals (4.3%) obtained clinically elevated scores on all three measures. The co-occurrence of apathy and ICD varied across measures.

CONCLUSIONS

We observed a co-occurrence of apathy and ICDs in PD patients with each apathy instrument; however, limited concurrent validity exists across measures. This is important for future investigations into shared pathophysiology and the design of future clinical trials aimed at improving the early detection and treatment of these debilitating syndromes.

The Relationship Between Autonomic Dysfunction and Mood Symptoms in De Novo Parkinson's Disease Patients Over Time

BACKGROUND

Autonomic dysfunction is prevalent in Parkinson's disease (PD) and can worsen quality of life. We examined: (a) whether specific autonomic symptoms were more strongly associated with anxiety or depression in PD and (b) whether overall autonomic dysfunction predicted mood trajectories over a 5-year period.

METHODS

Newly diagnosed individuals with PD (N = 414) from the Parkinson's Progression Markers Initiative completed self-report measures of depression, anxiety, and autonomic symptoms annually. Cross-sectional linear regressions examined relationships between specific autonomic subdomains (gastrointestinal, cardiovascular, thermoregulatory, etc.) and mood. Multilevel modeling examined longitudinal relationships with total autonomic load.

RESULTS

Gastrointestinal symptoms were associated with both higher anxiety (b = 1.04, 95% CI [.55, 1.53], P < .001) and depression (b = .24, 95% CI [.11, .37], P = .012), as were thermoregulatory symptoms (anxiety: b = 1.06, 95% CI [.46, 1.65], P = .004; depression: b = .25, 95% CI [.09, .42], P = .013), while cardiovascular (b = .36, 95% CI [.10, .62], P = .012) and urinary symptoms (b = .10, 95% CI [.01, .20], P = .037) were associated only with depression. Longitudinally, higher total autonomic load was associated with increases in both depression (b = .01, 95% CI [.00, .02], P = .015) and anxiety (b = .04, 95% CI [.01, .06], P < .001) over time, as well as occasion-to-occasion fluctuations (depression: b = .08, 95% CI [.05, .10], P < .001; anxiety: b = .24, 95% CI [.15, .32], P < .001).

CONCLUSION

Findings suggest autonomic dysfunction, particularly gastrointestinal and thermoregulatory symptoms, may be an indicator for elevated anxiety/depression and a potential treatment target early on in PD.

Perception of cognitive change by individuals with Parkinson's disease or essential tremor seeking deep brain stimulation: Utility of the cognitive change index

OBJECTIVE

The Cognitive Change Index (CCI-20) is a validated questionnaire that assesses subjective cognitive complaints (SCCs) across memory, language, and executive domains. We aimed to: (a) examine the internal consistency and construct validity of the CCI-20 in patients with movement disorders and (b) learn how the CCI-20 corresponds to objective neuropsychological and mood performance in individuals with Parkinson's disease (PD) or essential tremor (ET) seeking deep brain stimulation (DBS).

METHODS

216 participants (N = 149 PD; N = 67 ET) underwent neuropsychological evaluation and received the CCI-20. The proposed domains of the CCI-20 were examined via confirmatory (CFA) and exploratory (EFA) factor analyses. Hierarchical regressions were used to assess the relationship among subjective cognitive complaints, neuropsychological performance and mood symptoms.

RESULTS

PD and ET groups were similar across neuropsychological, mood, and CCI-20 scores and were combined into one group who was well educated (m = 15.01 ± 2.92), in their mid-60's (m = 67.72 ± 9.33), predominantly male (63%), and non-Hispanic White (93.6%). Previously proposed 3-domain CCI-20 model failed to achieve adequate fit. Subsequent EFA revealed two CCI-20 factors: memory and non-memory (p < 0.001; CFI = 0.924). Regressions indicated apathy and depressive symptoms were associated with greater memory and total cognitive complaints, while poor executive function and anxiety were associated with more non-memory complaints.

CONCLUSION

Two distinct dimensions were identified in the CCI-20: memory and non-memory complaints. Non-memory complaints were indicative of worse executive function, consistent with PD and ET cognitive profiles. Mood significantly contributed to all CCI-20 dimensions. Future studies should explore the utility of SCCs in predicting cognitive decline in these populations.

Responsive deep brain stimulation for the treatment of Tourette syndrome

To report the results of 'responsive' deep brain stimulation (DBS) for Tourette syndrome (TS) in a National Institutes of Health funded experimental cohort. The use of 'brain derived physiology' as a method to trigger DBS devices to deliver trains of electrical stimulation is a proposed approach to address the paroxysmal motor and vocal tic symptoms which appear as part of TS. Ten subjects underwent bilateral staged DBS surgery and each was implanted with bilateral centromedian thalamic (CM) region DBS leads and bilateral M1 region cortical strips. A series of identical experiments and data collections were conducted on three groups of consecutively recruited subjects. Group 1 (n = 2) underwent acute responsive DBS using deep and superficial leads. Group 2 (n = 4) underwent chronic responsive DBS using deep and superficial leads. Group 3 (n = 4) underwent responsive DBS using only the deep leads. The primary outcome measure for each of the 8 subjects with chronic responsive DBS was calculated as the pre-operative baseline Yale Global Tic Severity Scale (YGTSS) motor subscore compared to the 6 month embedded responsive DBS setting. A responder for the study was defined as any subject manifesting a ≥ 30 points improvement on the YGTSS motor subscale. The videotaped Modified Rush Tic Rating Scale (MRVTRS) was a secondary outcome. Outcomes were collected at 6 months across three different device states: no stimulation, conventional open-loop stimulation, and embedded responsive stimulation. The experience programming each of the groups and the methods applied for programming were captured. There were 10 medication refractory TS subjects enrolled in the study (5 male and 5 female) and 4/8 (50%) in the chronic responsive eligible cohort met the primary outcome manifesting a reduction of the YGTSS motor scale of ≥ 30% when on responsive DBS settings. Proof of concept for the use of responsive stimulation was observed in all three groups (acute responsive, cortically triggered and deep DBS leads only). The responsive approach was safe and well tolerated. TS power spectral changes associated with tics occurred consistently in the low frequency 2-10 Hz delta-theta-low alpha oscillation range. The study highlighted the variety of programming strategies which were employed to achieve responsive DBS and those used to overcome stimulation induced artifacts. Proof of concept was also established for a single DBS lead triggering bi-hemispheric delivery of therapeutic stimulation. Responsive DBS was applied to treat TS related motor and vocal tics through the application of three different experimental paradigms. The approach was safe and effective in a subset of individuals. The use of different devices in this study was not aimed at making between device comparisons, but rather, the study was adapted to the current state of the art in technology. Overall, four of the chronic responsive eligible subjects met the primary outcome variable for clinical effectiveness. Cortical physiology was used to trigger responsive DBS when therapy was limited by stimulation induced artifacts.

Dose response of transcranial near infrared light stimulation on brain functional connectivity and cognition in older adults-A randomized comparison

Photobiomodulation, also called low-level light therapy, has been reported in animal studies to have an effect on brain activity and cognition. However, studies in humans regarding its effect on cognition and brain functional connectivity, and the required dose threshold for achieving the same have been very limited. We compared the effects of different doses of photobiomodulation (PBM) on cognition and resting state brain functional connectivity in 25 cognitively normal adults aged 55-70 years. They were randomized to a single session of the sham group, "low-dose" and "high-dose" groups receiving NIR light with transcranial fluence of 26 and 52 J/cm2 respectively, and intranasal fluence of 9 and 18 J/cm2 respectively. There was a significant increase in resting state functional connectivity of the left superior frontal gyrus (SFG) with the left planum temporale (PT), p = 0.0016, and with the left inferior frontal gyrus, pars triangularis, p = 0.0235 in the "high-dose" group only compared to the "sham" group. There was also a significant improvement in visual search and processing speed (p = 0.012) in the "high-dose" group. Replication of these findings in an adequately powered randomized sham-controlled study in healthy older adults can pave the way for clinical application of NIRL as a therapeutic modality in patients with Alzheimer's disease.

A - 97 Anticholinergic Burden Scales Are Not Created Equal: Differential Relationships to Cognition in Parkinson's Disease

OBJECTIVE

Cognitive changes are common in Parkinson's disease (PD). While previous research suggests greater anticholinergic medication use relates to worse broad cognition in PD, its domain-specific relationships remain unknown. This study compared three anticholinergic scales to examine their relationship to worse memory and executive function in individuals with PD.

METHOD

Participants included 493 non-demented individuals with PD (mean age = 65.74, SD = 9.04; mean education = 15.0, SD = 2.79; 72% male; 94% White (non-Hispanic)) from a movement disorders specialty clinic. Medications were identified via chart review. Each medication was scored (0-3) and summed using three scales: Anticholinergic Risk Scale (ARS), Anticholinergic Drug Scale (ADS), Anticholinergic Cognitive Burden Scale (ACBS). Cognitive composites averaged normative z-scores: Executive Function (EF; Trails B, Stroop Color-Word, Letter Fluency) and Memory (HVLT-R and WMS-III Logical Memory delayed recalls). Analyses included Bonferroni-adjusted, bootstrapped Spearman correlations.

RESULTS

The three scales were significantly related, but with only fair agreement (Kendall's W(2) = 0.37, p < 0.001). Worse memory related to higher cholinergic burden on only the ACBS (r = -0.10, p = 0.02). Exploratory analyses indicated sex differences in the relationship between cognition and anticholinergic burden. For men, worse memory related to higher scores on both the ACBS (r = -0.11, p = 0.04) and ARS (r = -0.11, p = 0.045). For women, higher ACBS scores related to worse EF (r = -0.18, p = 0.03), whereas higher ADS scores related to worse memory and EF (r = -0.18, p = 0.04; r = -0.26, p = 0.002).

CONCLUSIONS

Anticholinergic burden scales differentially related to cognitive performance in PD, with only ACBS showing a significant relationship to memory. Exploratory analyses suggest that scales may have differential relationships to memory and EF in men and women.

H - 68 Effects of Depression, Apathy and Anxiety in Hispanic Parkinson Disease Individuals' Cognition

OBJECTIVE

Previous research in individuals with Parkinson's disease (PD) found that heightened apathy is associated with worse executive function. Most studies to-date have involved primarily White, non-Hispanic individuals. Indeed, recent research suggests that mood/motivation's relationship to cognitive decline differs between Hispanic and non-Hispanic individuals (Thakur et al., 2021). In this study, we examined relationships between depression, apathy, anxiety, and cognition in Hispanic PD participants who were seen in a specialized movement disorders center.

METHODS

Participants included 31 non-demented Hispanic individuals with PD (age mean = 59.94, SD = 8.49 years; education mean = 14.39, SD = 2.79; 83.9% male) who completed neuropsychological and mood measures (Beck Depression Inventory-II, Apathy Scale, STAI-Trait Anxiety Scale). Prevalence estimates were calculated using established cut-offs (BDI-II:14, AS:14, STAI-Trait:40). Cognitive raw scores were z-scored and averaged into the composites: attention (WAIS-III Digit Span Forward, Backward), processing speed (Stroop Word, Trails A), executive function (Trails B, Stroop Color-Word), and memory (Hopkin's Verbal Learning Test, WMS-III Logical Memory delayed recalls). Non-parametric partial correlations (correcting for age/education) assessed mood and cognitive composite relationships.

RESULTS

17% had clinically significant depressive symptoms, 12% had apathy, and 35% had anxiety. More depressive symptoms were significantly associated with worse memory (r = -0.54, p = 0.007). Greater anxiety symptoms trended with worse processing speed (r = -0.41, p = 0.065) and memory (r = -0.38, p = 0.094). Apathy did not relate to cognition (p's > 0.05).

CONCLUSION

This pattern of associations differs from existing studies with predominantly White, non-Hispanic samples (Butterfield et al., 2010; Ratajska, et al.,2022), highlighting the importance of further investigating ethnic differences in PD.

Frontal adenosine triphosphate markers from 31P MRS are associated with cognitive performance in healthy older adults: preliminary findings

Aging is associated with declines in mitochondrial efficiency and energy production which directly impacts the availability of adenosine triphosphate (ATP), which contains high energy phosphates critical for a variety of cellular functions. Previous phosphorous magnetic resonance spectroscopy (31P MRS) studies demonstrate cerebral ATP declines with age. The purpose of this study was to explore the functional relationships of frontal and posterior ATP levels with cognition in healthy aging. Here, we measured frontal and posterior ATP levels using 31P MRS at 3 Tesla (3 T) and assessed cognition using the Montreal Cognitive Assessment (MoCA) in 30 healthy older adults. We found that greater frontal, but not posterior, ATP levels were significantly associated with better MoCA performance. This relationship remained significant after controlling for age, sex, years of education, and brain atrophy. In conclusion, our findings indicate that cognition is related to ATP in the frontal cortex. These preliminary findings may have important implications in the search for non-invasive markers of in vivo mitochondrial function and the impact of ATP availability on cognition. Future studies are needed to confirm the functional significance of regional ATP and cognition across the lifespan.

Early rapid eye movement sleep behavior disorder predicts incident cognitive impairment in Parkinson's disease across ages

This study demonstrated possible rapid eye movement sleep behavior disorder (RBD)'s relationship to longitudinal, incident cognitive impairment in the Parkinson's Progression Markers Initiative (PPMI) database. Age did not moderate this relationship, suggesting that RBD serves as a cognitive risk factor across individuals of all ages with recently diagnosed Parkinson's disease.

Unpacking the NIH Toolbox Emotion Battery in Persons With Parkinson's disease

OBJECTIVE

Examine the relationship between the National Institutes of Health Toolbox Emotion Battery (Emotion Toolbox) and traditional measures in Parkinson's disease (PD).

METHOD

Persons with PD (n = 30) and cognitively healthy older adults (OA; n = 40) completed the Emotion Toolbox consisting of Well-Being, Negative Affect, and Social Satisfaction scores along with traditional measures of depression (Beck Depression Inventory-II [BDI-II]), anxiety (State-Trait Anxiety Inventory [STAI]), and apathy (Apathy Scale [AS]); total raw scores).

RESULTS

Separate bootstrapped analyses of covariance indicated that the PD group scored higher on BDI-II and STAI-State compared to OA (ps < .01); groups did not differ on Emotion Toolbox. In the PD group, bootstrapped partial correlations indicated that Negative Affect was positively related to BDI-II and STAI (ps ≤ .001). Social Satisfaction was negatively related to BDI-II and STAI-Trait (.05 < ps < .004). Psychological Well-Being was negatively related to BDI-II, AS, and STAI (p < .004). No relationships emerged in OA. In the PD group, separate binary logistic regressions showed that traditional measures (BDI-II, AS, and STAI-Trait) correctly classified 79.6% those with formal psychiatric diagnoses (presence vs. absence; p < .011), whereas Emotion Toolbox measures correctly classified 73.3% (p < .019).

CONCLUSIONS

The Emotion Toolbox showed moderate-strong correlations with traditional measures in persons with PD. Even so, it did not capture the group differences between PD and OA and had a somewhat lower classification accuracy rate for persons with PD who had a formal psychiatric diagnosis than traditional measures. Together, findings question the utility of the Emotion Toolbox as a stand-alone emotion screener in PD.

A Pilot Trial of Dopamine Replacement for Dynamic Facial Expressions in Parkinson's Disease

Background

Current conflict exists regarding the potential beneficial effects of dopamine medications on facial expressivity in Parkinson's disease. Via digital video analysis software, we previously found reduced facial movement (entropy) and slower time to reach peak entropy in individuals with Parkinson's disease compared to controls.

Objectives

We aimed to determine whether levodopa medications improved parameters of dynamic facial expressions (amplitude, speed).

Methods

A total of 34 individuals with idiopathic Parkinson's disease were videotaped making voluntary facial expressions (happy, fear, anger, disgust) when "on" and "off" levodopa. Participants were 52 to 80 years old, early to mid-stage disease, non-demented, and included more men (65%). Expressions were digitized and analyzed using software that extracted three variables: two indices of movement change (total entropy, percent entropy change) and time to reach peak expression.

Results

Indices of facial movement (total entropy, peak entropy) and timing were significantly improved when patients were "on" vs "off" medication (all F's ≥ 3.00, P < 0.05). For total movement and time to reach peak entropy, levodopa-related improvements were emotion nonspecific. Levodopa-related improvement for peak entropy was driven primarily by happy expressions. There was no relationship between quantitative indices and clinical measures of mood (depression, anxiety) and motor disease severity.

Conclusion

The effects of levodopa on Parkinson's disease voluntary facial movement and on timing were robust and consistent with those of levodopa on other intentional movements in Parkinson's disease. This improvement possibly occurred because of levodopa enhanced activation of face representation areas in fronto-cortical regions or because of less movement-based suppression.

What does the Dementia Rating Scale-2 measure? The relationship of neuropsychological measures to DRS-2 total and subscale scores in non-demented individuals with Parkinson's disease

OBJECTIVE

The Dementia Rating Scale-2 (DRS-2) is recommended for assessing global cognition in Parkinson's disease (PD) by the Movement Disorder Society. However, empirical evidence is limited regarding the degree to which the DRS-2 corresponds to traditional neurocognitive domains (i.e., construct validity) in PD. Thus, this study aims to determine the construct validity of the DRS-2 in a non-demented sample of PD patients.

METHOD

Patients with PD (n = 359; mean age = 64.50 ± 8.53, education = 14.97 ± 2.73, disease duration = 8.48 ± 4.87, UPDRS Part III motor scale scores = 25.23 ± 10.17) completed the DRS-2 as part of a comprehensive neuropsychological assessment consisting of attention/working memory, executive function, language, delayed recall, and visuoperceptual-spatial skills.Bootstrapped bias-corrected Spearman rho's correlations andhierarchical linear regressions were performed to examine construct validity of DRS-2 total and subscale scores.

RESULTS

Speeded measures of set-shifting, rapid word generation to letter and semantic cues, and simple visuoperceptual skills largely accounted for variance in DRS-2 total scores. Most DRS-2 subscale scores showed weak relationships with theoretically related neuropsychological measures.

CONCLUSIONS

DRS-2 total scores reflect impairment across a range of cognitive domains (i.e., executive, language, and visuoperception), while DRS-2 subscale scores have limited construct validity. Together, the DRS-2 does not appear to have utility beyond screening for global cognition in PD.

From pleasure to punding: Distinct patterns of anhedonia and impulsivity linked to motivational disturbances in Parkinson disease

INTRODUCTION

Apathy and impulse control disorders (ICD) are common comorbid motivational syndromes in Parkinson disease (PD). This study aimed to determine if patients with these motivational disturbances exhibit different patterns of anhedonia and trait impulsivity.

METHODS

Sixty-four non-demented patients with PD completed questionnaires assessing apathy and ICD symptoms, which were used to classify participants into one of the following groups: apathy only, ICD only, both, and neither. Participants also completed multidimensional measures of anhedonia and trait impulsivity, which were compared across groups defined by motivational status.

RESULTS

Individuals with both apathy and ICD had significantly greater symptoms of positive and negative urgency than all other groups and had significantly greater consummatory anhedonia and lack of premeditation and perseverance than those with ICD only and neither. Patients with apathy only also reported significantly greater anticipatory anhedonia than those with ICD only and the neither group. There were no significant between-group differences in sensation seeking.

CONCLUSION

Distinct patterns of impulsivity and anhedonia characterize unique behavioral phenotypes of motivational disturbances in PD and may reflect important differences in the underlying neurobiological mechanisms. Clinicians should be aware that motivational disturbances may be more severe in cases where apathy co-occurs with one or more ICD.HIGHLIGHTSHighlights are mandatory for all submissions except letters. They consist of a short collection of bullet points that convey the core findings of the article and should be submitted in a separate file in the online submission system. Please use "Highlights" in the file name and include 3-5 bullet points (maximum 85 characters, including spaces, per bullet point). See https://www.elsevier.com/highlights for examples.

Differential contributions of depression, apathy, and anxiety to neuropsychological performance in Parkinson's disease versus essential tremor

INTRODUCTION

Mood symptoms are common features of Parkinson's disease (PD) and essential tremor (ET) and have been linked to worse cognition. The goals of the present study were to compare the severity of anxiety, apathy, and depressive symptoms in PD, ET, and healthy controls (HC) and to examine differential relationships between mood and cognition.

METHOD

Older adults with idiopathic PD (N = 448), ET (N = 128), or HC (N = 136) completed a multi-domain neuropsychological assessment consisting of memory, executive function, and attention/working memory domains. Participants also completed self-reported mood measures. Between-group differences in mood and cognition were assessed, and hierarchical regression models were conducted to examine relationships between mood and cognition in each group.

RESULTS

Relative to the HC group, the PD and ET groups reported more mood symptoms and scored lower across all cognitive measures. There were no differences between the two movement disorder groups. Mood variables explained 3.9-13.7% of the total variance in cognitive domains, varying by disease group. For PD, apathy was the only unique predictor of executive function (β = -.114, p = .05), and trait anxiety was the only unique predictor of attention/working memory (β = -.188, p < .05). For ET, there were no unique predictors, though the overall models significantly predicted performance in the executive function and attention/working memory domains.

CONCLUSIONS

In a large cohort of ET and PD, we observed that the two groups had similar self-reported mood symptoms. Mood symptoms were differentially associated with cognition in PD versus ET. In PD, increased apathy was associated with worse executive function and higher trait anxiety predicted worse attention/working memory. For ET, there were no unique predictors, though the overall mood symptom severity was related to cognition. Our study highlights the importance of considering the relationship between mood and neuropsychological performance in individuals with movement disorders.

Cognitive subtypes in individuals with essential tremor seeking deep brain stimulation

Objective: Essential tremor (ET) is a common neurological disorder that has been associated with 60% increased risk of developing dementia. The goals of the present study were to: (a) learn whether individuals with advanced ET symptoms seeking deep brain stimulation (DBS) surgery would fall into distinct cognitive subgroups, and (b) learn how empirically derived subgroups map onto criteria for mild cognitive impairment (MCI). Method: Patients with ET (N = 201; mean age = 68.9 ± 8.9 years) undergoing pre-surgical evaluation for DBS completed a multi-domain neurocognitive assessment consisting of memory, executive function, visuospatial skill, language, and processing speed. Two cluster analytic approaches (K-means, hierarchical) were independently conducted to classify cognitive patterns using domain composites. Demographics, clinical characteristics, and proportion of cases meeting neuropsychologically defined criteria for MCI were examined among clusters. Results: A three-cluster solution reflected a Low Executive group (N = 64), Low Memory Multi-Domain group (N = 41), and Cognitively Normal group (N = 96). The Cognitively Normal group was older and more educated, with a higher Dementia Rating Scale-2 score. In total, 27.4% of participants met criteria for MCI. Of the MCI cases, most were in the Low Executive (41.8%) or Low Memory Multi-Domain groups (49.1%). In the latter, 65.9% of its members were classified as MCI versus 35.9% in the Low Executive group. Conclusions: Our study identified three cognitive subtypes of ET patients presenting for DBS. Future work should examine the subgroups for progression to dementia, particularly the Low Memory Multi-Domain subgroup which may be at highest risk.

Embedded Human Closed-Loop Deep Brain Stimulation for Tourette Syndrome: A Nonrandomized Controlled Trial

Importance

Because Tourette syndrome (TS) is a paroxysmal disorder, symptomatic relief in individuals with TS may be possible through the application of stimulation only during the manifestation of human tic neural signatures. This technique could be capable of suppressing both motor and vocal tics and would have similar effectiveness to conventional continuous deep brain stimulation (DBS).

Objective

To evaluate the feasibility, safety, and clinical effectiveness of bilateral centromedian-parafascicular complex thalamic closed-loop DBS as a treatment for medication-refractory TS.

Design, Setting, and Participants

This single-center double-blinded safety and feasibility trial was conducted between February 2014 and June 2020. Six individuals with TS were screened and recruited from the Norman Fixel Institute at the University of Florida. The primary outcome was measured at 6 months, and participants were followed up for the duration of the neurostimulator battery life. Independent ratings that compared closed-loop and conventional DBS were videotaped. The first 2 of 6 individuals with TS were excluded from the study because the technology for embedded closed-loop capability was not yet available. The date of analysis was August 2020.

Interventions

DBS therapy controlled by an embedded closed-loop stimulation system.

Main Outcomes and Measures

The primary clinical outcome measure was a minimum of a 40% reduction in the YGTSS score at 6 months following DBS. There was also a comparison of conventional DBS with closed-loop DBS using the Modified Rush Videotape Rating Scale for Tic.

Results

The mean (SD) age at TS diagnosis for the cohort was 8.5 (2.9), and the mean (SD) disease duration was 23.7 (5.8) years. Four individuals with TS were analyzed (2 male, 2 female; mean [SD] age, 23.7 [5.8] years). The study showed the closed-loop approach was both feasible and safe. One of the novelties of this study was that a patient-specific closed-loop paradigm was created for each participant. The features and stimulation transition speed were customized based on the signal quality and the tolerance to adverse reactions. The mean (SD) therapeutic outcome with conventional DBS was 33.3% (35.7%) improvement on the YGTSS and 52.8% (21.9%) improvement on the Modified Rush Videotape Rating Scale. Two of 4 participants had a primary outcome variable improvement of 40% meeting the primary efficacy target. When comparing closed-loop DBS with conventional DBS using a Wilcoxon sign-rank test, there was no statistical difference between tic severity score and both approaches revealed a lower tic severity score compared with baseline. The study was feasible in all 4 participants, and there were 25 total reported adverse events with 3 study-related events (12%). The most common adverse events were headache and anxiety.

Conclusions and Relevance

Embedded closed-loop deep DBS was feasible, safe, and had a comparable outcome to conventional TS DBS for the treatment of tics.

Trial Registration

ClinicalTrials.gov Identifier: NCT02056873.

Online vs Face-to-Face Administration of Impulse Control Disorder Questionnaires in Parkinson Disease: Does Method Matter?

Background:

Social desirability bias, the tendency to underreport undesirable behaviors, may be one reason patients with Parkinson disease (PD) underreport symptoms of impulse control disorders (ICDs).

Methods:

We compared rates of ICD endorsement on questionnaires administered face-to-face and online in 60 patients with mild to moderate idiopathic PD. Participants also completed a self-report measure of social desirability.

Results:

We found significantly higher prevalence of any ICD based on online (56.7%) versus in-person (33.3%) administration. Significantly higher endorsement of items related to hypersexuality in men, and compulsive eating and buying in women were found with online administration. Social desirability bias was positively correlated with ICD symptom endorsement across all items and subscales.

Conclusion:

Results highlight the importance of social context/setting and the need for sensitivity and discretion when screening for ICD symptoms. While a higher level of symptom endorsement does not necessarily imply a greater level of accuracy, more work is needed to determine which method of administration is most accurate for clinical and research practice.

Central Nervous System Manifestations of COVID-19: A Critical Review and Proposed Research Agenda

OBJECTIVE

On March 11, 2020, the World Health Organization declared an outbreak of a new viral entity, coronavirus 2019 (COVID-19), to be a worldwide pandemic. The characteristics of this virus, as well as its short- and long-term implications, are not yet well understood. The objective of the current paper was to provide a critical review of the emerging literature on COVID-19 and its implications for neurological, neuropsychiatric, and cognitive functioning.

METHOD

A critical review of recently published empirical research, case studies, and reviews pertaining to central nervous system (CNS) complications of COVID-19 was conducted by searching PubMed, PubMed Central, Google Scholar, and bioRxiv.

RESULTS

After considering the available literature, areas thought to be most pertinent to clinical and research neuropsychologists, including CNS manifestations, neurologic symptoms/syndromes, neuroimaging, and potential long-term implications of COVID-19 infection, were reviewed.

CONCLUSION

Once thought to be merely a respiratory virus, the scientific and medical communities have realized COVID-19 to have broader effects on renal, vascular, and neurological body systems. The question of cognitive deficits is not yet well studied, but neuropsychologists will undoubtedly play an important role in the years to come.

Laterality of motor symptom onset and facial expressivity in Parkinson disease using face digitization

The onset of motor symptoms in Parkinson disease (PD) is typically unilateral. Previous work has suggested that laterality of motor symptoms may also influence non-motor symptoms including cognition and emotion perception. In line with hemispheric differences in emotion processing, we tested whether left side/right brain motor onset was associated with worse expression of facial affect when compared to right side/left brain motor onset. We evaluated movement changes associated with facial affect in 30 patients with idiopathic PD (15 left-sided motor onset, 15 right-sided motor onset) and 20 healthy controls. Participants were videotaped while posing three facial expressions: fear, anger, and happiness. Expressions were digitized and analyzed using software that extracted three variables: two measures of dynamic movement change (total entropy and entropy percent change) and a measure of time to initiate facial expression (latency). The groups did not differ in overall amount of movement change or percentchange. However, left-sided onset PD patients were significantly slower in initiating anger and happiness facial expressions than were right-sided onset PD patients and controls. Our results indicated PD patients with left-sided symptom onset had greater latency in initiating two of three facial expressions, which may reflect laterality effects in intentional behaviour.

Lewy Body Dementias: Controversies and Drug Development

Lewy body dementia (LBD) is one of the most common neurodegenerative dementias. Clinical trials for symptomatic and disease-modifying therapies in LBD remain a national research priority, but there are many challenges in both past and active drug developments in LBD. This review highlights the controversies in picking the appropriate populations, interventions, target selections, and outcome measures, which are all critical components of clinical trial implementation in LBD. The heterogeneity of LBD neuropathology and clinical presentations, limited understanding of core features such as cognitive fluctuations, and lack of validated LBD-specific outcome measures and biomarkers represent some of the major challenges in LBD trials.

Double blind randomized controlled trial of deep brain stimulation for obsessive-compulsive disorder: Clinical trial design

Obsessive-compulsive disorder (OCD), a leading cause of disability, affects ~1–2% of the population, and can be distressing and disabling. About 1/3 of individuals demonstrate poor responsiveness to conventional treatments. A small proportion of these individuals may be deep brain stimulation (DBS) candidates. Candidacy is assessed through a multidisciplinary process including assessment of illness severity, chronicity, and functional impact. Optimization failure, despite multiple treatments, is critical during screening. Few patients nationwide are eligible for OCD DBS and thus a multi-center approach was necessary to obtain adequate sample size. The study was conducted over a six-year period and was a NIH-funded, eight-center sham-controlled trial of DBS targeting the ventral capsule/ventral striatum (VC/VS) region. There were 269 individuals who initially contacted the sites, in order to achieve 27 participants enrolled. Study enrollment required extensive review for eligibility, which was overseen by an independent advisory board. Disabling OCD had to be persistent for ≥5 years despite exhaustive medication and behavioral treatment. The final cohort was derived from a detailed consent process that included consent monitoring. Mean illness duration was 27.2 years. OCD symptom subtypes and psychiatric comorbidities varied, but all had severe disability with impaired quality of life and functioning. Participants were randomized to receive sham or active DBS for three months. Following this period, all participants received active DBS. Treatment assignment was masked to participants and raters and assessments were blinded. The final sample was consistent in demographic characteristics and clinical features when compared to other contemporary published prospective studies of OCD DBS. We report the clinical trial design, methods, and general demographics of this OCD DBS sample.

A Validation Study of PROMIS Sleep Disturbance (PROMIS-SD) and Sleep Related Impairment (PROMIS-SRI) Item Banks in Individuals with Idiopathic Parkinson's Disease and Matched Controls

BACKGROUND

Parkinson's disease (PD) is associated with sleep disturbance (SD) and sleep-related impairment (SRI). Validation of self-report measures of these problems is needed in PD. The Patient-Reported Outcomes Measurement Information System (PROMIS) includes tools that assess these problems (PROMIS-SD and PROMIS-SRI, respectively).

OBJECTIVE

This study aimed to further validate these measures in individuals with PD and matched controls.

METHODS

Individuals with early-stage PD (n=50) and matched controls (n=48) completed measures of SD including the PROMIS-SD, Pittsburgh Sleep Quality Index (PSQI), and Insomnia Severity Index (ISI). They also completed measures of daytime impairment including the PROMIS-SRI, Epworth Sleepiness Scale, State-Trait Anxiety Inventory, Beck Depression Inventory 2nd edition, and Parkinson's Disease Questionnaire-39. Internal consistency for the PROMIS measures were assessed using Cronbach's α coefficient and item-total correlations in the total sample. Convergent and divergent validity of the PROMIS item banks were assessed using Spearman correlations.

RESULTS

The PROMIS item banks had excellent internal consistency (α>0.94). Supporting convergent validity, the PROMIS-SD had strong correlations with other measures of SD (ρ>0.68, for PSQI and ISI) and the PROMIS-SRI had moderate to strong correlations with all measures of daytime impairment (ρ=0.41-0.72). Supporting divergent validity within the PD group, the PROMIS-SD correlated more strongly with SRI than with the Parkinson's Disease Questionnaire total score, a metric of PD related impairment.

CONCLUSION

In middle-aged and older adults, with and without early-stage PD, the PROMIS-SD and PROMIS-SRI are reliable and valid measures of SD and SRI, respectively.

Statistically Defined Parkinson's Disease Executive and Memory Cognitive Phenotypes: Demographic, Behavioral, and Structural Neuroimaging Comparisons

BACKGROUND

Some individuals with Parkinson's disease (PD) experience working memory and inhibitory difficulties, others learning and memory difficulties, while some only minimal to no cognitive deficits for many years.

OBJECTIVE

To statistically derive PD executive and memory phenotypes, and compare PD phenotypes on disease and demographic variables, vascular risk factors, and specific neuroimaging variables with known associations to executive and memory function relative to non-PD peers.

METHODS

Non-demented individuals with PD (n = 116) and non-PD peers (n = 62) were recruited to complete neuropsychology measures, blood draw, and structural magnetic resonance imaging. Tests representing the cognitive domains of interest (4 executive function, 3 memory) were included in a k-means cluster analysis comprised of the PD participants. Resulting clusters were compared demographic and disease-related variables, vascular risk markers, gray/white regions of interest, and white matter connectivity between known regions involved in executive and memory functions (dorsolateral prefrontal cortices to caudate nuclei; entorhinal cortices to hippocampi).

RESULTS

Clusters showed: 1) PD Executive, n = 25; 2) PD Memory, n = 35; 3) PD Cognitively Well; n = 56. Even after disease variable corrections, PD Executive had less subcortical gray matter, white matter, and fewer bilateral dorsolateral-prefrontal cortex to caudate nucleus connections; PD Memory showed bilaterally reduced entorhinal-hippocampal connections. PD Cognitively Well showed only reduced putamen volume and right entorhinal cortex to hippocampi connections relative to non-PD peers. Groups did not statistically differ on cortical integrity measures or cerebrovascular disease markers.

CONCLUSION

PD cognitive phenotypes showed different structural gray and white matter patterns. We discuss data relative to phenotype demographics, cognitive patterns, and structural brain profiles.

Cognitive Outcomes for Essential Tremor Patients Selected for Thalamic Deep Brain Stimulation Surgery Through Interdisciplinary Evaluations

Objective: Deep brain stimulation (DBS) targeted to the ventral intermediate (VIM) nucleus of the thalamus is effective for motor symptoms in essential tremor (ET), but there is limited data on cognitive outcomes. We examined cognitive outcomes in a large cohort of ET DBS patients (pre-DBS and 1+ year after DBS).

Methods: In a retrospective analysis, we used repeated-measures ANOVA testing to examine whether the age of tremor onset, age at DBS surgery, hemisphere side implanted with lead, unilateral vs. bilateral implantations, and presence of surgical complications influenced the cognitive outcomes. Neuropsychological outcomes of interest were verbal memory, executive functioning, working memory, language functioning, visuospatial functioning, and general cognitive function.

Results: We identified 50 ET DBS patients; 29 (58%) males; the mean age of tremor onset was 35.84 (±21.50) years with a median age of 38 years. The mean age at DBS was 68.18 (±10.07) years. There were 37 unilateral 30 left, seven right, and 13 bilateral brain implantations. In the subgroup analysis, there was a significant interaction between assessment (pre vs. post) and age of tremor onset (<38 vs. >38 years); F_(1,30) = 4.47; p = 0.043 for working memory. The post hoc testing found improvements for younger onset ET. Similarly, there was a significant interaction between assessment (pre vs. post) and complications vs. no complications subgroups; F_(1,45) = 4.34; p = 0.043 for verbal memory with worsening scores seen for ET patients with complications. The remaining tests were not significant.

Conclusion: In this large cohort of ET patients with (>30% improvements), DBS was not accompanied by a significant decline in many cognitive domains. These outcomes were possibly related to the selection of patients with normal cognitive functioning before surgery, unilateral DBS implantations for the majority, and selection of patients with optimal response to DBS.

Long-term clinical outcomes of bilateral GPi deep brain stimulation in advanced Parkinson's disease: 5 years and beyond

OBJECTIVE

Few studies have reported long-term outcomes of globus pallidus internus (GPi) deep brain stimulation (DBS) in Parkinson's disease (PD). The authors aimed to investigate long-term outcomes of bilateral GPi DBS for 5 years and beyond for PD patients.

METHODS

The authors retrospectively analyzed the clinical outcomes in 65 PD patients treated with bilateral GPi DBS at a single center. The outcome measures of motor symptoms and health-related quality of life (HRQoL) included the Unified Parkinson's Disease Rating Scale (UPDRS) and the Parkinson's Disease Questionnaire (PDQ-39). Scores at baseline were compared with those at 1, 3, 5, and 6-8 years after implantation using Wilcoxon signed-rank tests with α correction.

RESULTS

GPi DBS significantly improved the off-medication UPDRS III total scores, UPDRS IV, and dyskinesia score at 1 year when compared with baseline (all p < 0.001). The off- and on-medication tremor scores, UPDRS IV, and dyskinesia scores showed moderate and sustained improvement (the ranges of the mean percentage improvement at each time point were 61%-75%, 30%-80%, 29%-40%, and 40%-65%, respectively) despite lacking statistical significance at long-term follow-up with diminishing sample sizes. The off-medication UPDRS III total scores did not show significant improvement at 5 years or later, primarily because of worsening in rigidity, akinesia, speech, gait, and postural stability scores. The on-medication UPDRS III total scores also worsened over time, with a significant worsening at 6-8 years when compared with baseline (p = 0.008). The HRQoL analyses based on the PDQ-39 revealed significant improvement in the activities of daily living and discomfort domains at 1 year (p = 0.003 and 0.006, respectively); however, all the domains showed gradual worsening at the later time points without reaching statistical significance. At 3 years, the communication domain showed significant worsening compared with baseline scores (p = 0.002).

CONCLUSIONS

GPi DBS in PD patients in this single-center cohort was associated with sustained long-term benefits in the off- and on-medication tremor score and motor complications. HRQoL and the cardinal motor symptoms other than tremor may worsen gradually in the long term. When counseling patients, it is important to recognize that benefits in tremor and dyskinesia are expected to be most persistent following bilateral GPi DBS implantation.

Co-occurrence of apathy and impulse control disorders in Parkinson disease

OBJECTIVE

To empirically test whether apathy and impulse control disorders (ICDs) represent independent, opposite ends of a motivational spectrum.

METHODS

In this single-center, cross-sectional study, we obtained retrospective demographics and clinical data for 887 patients with idiopathic Parkinson disease (PD) seen at a tertiary care center. Mood and motivation disturbances were classified using recommended cutoff scores from self-reported measures of apathy, ICD, anxiety, and depression.

RESULTS

Prevalence rates included 29.0% of patients with PD with depression, 40.7% with anxiety, 41.3% with apathy, 27.6% with ICDs, and 17.0% with both apathy and ICD. The majority (61.6%) of people reporting clinically significant ICDs also reported clinically significant apathy, and more than a third of patients with apathy (41.3%) also reported elevated ICD. Anxiety and depression were highest in patients with both apathy and ≥1 ICDs. Dopamine agonist use was higher in people with only ICD compared to people with only apathy. Mood significantly interacted with demographic variables to predict motivational disturbances.

CONCLUSIONS

Motivational disturbances are common comorbid conditions in patients with PD. In addition, these complex behavioral syndromes interact with mood in clinically important ways that may influence the design of future clinical trials and the development of novel therapies. This study challenges the concept of apathy and ICD in PD as opposite ends of a spectrum.

The UF Deep Brain Stimulation Cognitive Rating Scale (DBS-CRS): Clinical Decision Making, Validity, and Outcomes

To more efficiently communicate the results of neuropsychological assessment to interdisciplinary teams, the University of Florida Neuropsychology Service developed a Deep Brain Stimulation-Cognitive Rating Scale (DBS-CRS). This tool condensed results of a 3-h exam into a five-point scale ranging from 1 (least) to 5 (most) cognitive concern for DBS surgery. In this study, we evaluated the role of the DBS-CRS in clinical decisions by the interdisciplinary team to proceed to surgery, its relationship to objective neuropsychological scores, and its predictive utility for clinical outcome. We retrospectively examined 189 patients with Parkinson's disease who were evaluated for DBS candidacy (mean age 64.8 [SD 9.2], disease duration 8.9 years [SD 5.0], UPDRS-Part III off medication 38.5 [SD 10.5], Dementia Rating Scale-II 135.4 [SD 6.0]). Approximately 19% of patients did not proceed to surgery, with neuropsychological red flags being the most commonly documented reason (57%). Patients who underwent DBS surgery had significantly better DBS-CRS scores than those who did not (p < 0.001). The two strongest and unique neuropsychological contributors to DBS-CRS ratings were delayed memory and executive function, followed by language and visuoperception, based on hierarchical linear regression that accounted for 77.2% of the variance. In terms of outcome, DBS-CRS scores were associated with higher quality of life, less severe motor symptoms, and better daily functioning 6 months following DBS surgery. Together, these findings support the construct and predictive validity of the DBS-CRS as a concise tool for effectively communicating pre-DBS cognitive concerns to an interdisciplinary team, thereby aiding decision making in potential DBS candidates.

Pavlovian bias in Parkinson's disease: an objective marker of impulsivity that modulates with deep brain stimulation

Impulsivity is a common symptom in Parkinson's disease (PD). Adaptive behavior is influenced by prepotent action-reward and inaction-avoid loss Pavlovian biases. We aimed to assess the hypothesis that impulsivity in PD is associated with Pavlovian bias, and to assess whether dopaminergic medications and deep brain stimulation (DBS) influence Pavlovian bias. A PD DBS cohort (N = 37) completed a reward-based Go/No-Go task and bias measures were calculated. This DBS cohort completed the task under three conditions: on-med/pre-DBS, off-med/off-DBS, and on-med/on-DBS. Participants also completed self-reported measures of impulsivity. Dopaminergic medication was associated with lower action-reward bias while DBS was associated with higher action-reward bias. Impulsivity was associated with higher action-reward bias but not inaction-avoid loss bias. We furthermore replicated this association in an independent, non-DBS PD cohort (N = 88). Overall we establish an objective behavioral marker of impulsivity and show that DBS affects impulsivity by amplifying automated responding. Our results point to the importance of reward rather than punishment avoidance in driving impulsive behaviors. This work provides insight into the pathophysiological underpinnings of impulsivity and especially medication and DBS-associated impulsivity in PD.

A study of the clinical, treatment planning and dosimetric feasibility of dose painting in external beam radiotherapy of prostate cancer

BACKGROUND AND PURPOSE

Radiotherapy dose painting is a promising technique which enables dose escalation to areas of higher tumour cell density within the prostate which are associated with radioresistance, known as dominant intraprostatic lesions (DILs). The aim of this study was to determine factors affecting the feasibility of radiotherapy dose painting in patients with high and intermediate risk prostate cancer.

MATERIALS & METHODS

Twenty patients were recruited into the study for imaging using a 3 T magnetic resonance imaging (MRI) scanner. Identified DILs were outlined and the scan registered with the planning computed tomography (CT) dataset. Intensity-modulated plans were produced and evaluated to determine the effect of the organ-at-risk constraints on the dose that could be delivered to the DILs. Measurements were made to verify that the distribution could be safely delivered.

RESULTS

MRI scans were obtained for nineteen patients. Fourteen patients had one to two DILs with ten overlapping the urethra and/or rectum. The target boost of 86 Gy was achieved in seven plans but was limited to 80 Gy for five patients whose boost volume overlapped or abutted the urethra. Dosimetric measurements gave a satisfactory gamma pass rate at 3%/3 mm.

CONCLUSIONS

It was feasible to produce dose-painted plans for a boost of 86 Gy for approximately half the patients with DILs. The main limiting factor was the proximity of the urethra to the boost volumes. For a small proportion of patients, rigid registration between CT and MRI images was not adequate for planning purposes.

A tale of two stories: Validity of an alternative story memory test in a sample of older adults

Objective: Many patients require repeat neuropsychological evaluations to determine change over time. Repeat evaluations lead to practice effects, which can impact the validity of the assessment. The current study assessed, in older adults, the validity of an alternative set of verbal memory stories created by Newcomer and colleagues.Method: A total 154 of non-demented adults, ages 60-92, completed the WMS-III logical memory (LM) stories and two Newcomer stories (Carson-Jones) as part of a larger battery of neurocognitive tests. The Carson-Jones stories were scored for: (1) verbatim (traditional) and (2) thematic (developed for this study) accuracy. Story memory variables were compared to each other and additional neurocognitive measures using bivariate correlations. A subset of participants (n = 133) completed magnetic resonance imaging (MRI) and various structural regions (e.g. thickness and volume of medial temporal lobe structures) were used to assess external validity of Carson-Jones stories with hierarchical multiple regression analyses.Results: There was a strong positive correlation between WMS-III LM and Carson-Jones stories for both verbatim and thematic scoring. Both scoring types showed convergent validity with other verbal memory measures (e.g. WMS-III LM and HVLT-R Delay/Learning) and divergent validity with Stroop Word Reading and JOLO. Regarding neuroimaging correlates, Carson-Jones verbatim scoring was significantly associated with left subiculum and left whole hippocampal volume whereas thematic scoring was significantly associated only with left subiculum.Conclusions: Newcomer stories appear to be a valid alternative to WMS-III LM stories in terms of assessing verbal memory in healthy older adults.

Sniffing Out Cognitive Decline in Patients with and without Evidence of Dopaminergic Deficit

BACKGROUND

Depletion of dopamine is a major neuropathological feature of Parkinson's disease; however, 15% of patients with parkinsonian motor symptoms have neuroimaging evidence of intact dopaminergic function. Recent work has demonstrated that such patients without dopaminergic deficit are at a greater risk of cognitive impairment yet have intact olfaction relative to parkinsonian patients with dopaminergic deficit.

OBJECTIVES

Given the high discriminatory power of olfaction assessments in movement disorders, the current study sought to determine whether olfaction dysfunction differentially predicted cognitive decline in patients with or without dopaminergic deficit.

METHODS

Data were obtained from the Parkinson's Progression Marker Initiative. The total sample included 401 patients with and 51 patients without dopaminergic deficit, based on neuroimaging scans, and 175 healthy controls. Participants were categorized into non-impaired or impaired olfaction groups based on performance on the University of Pennsylvania Smell Identification Test. Participants were administered the Montreal Cognitive Assessment twice (baseline and two-year follow-up), and change scores were calculated to examine changes in cognition over time.

RESULTS

Within the impaired olfaction groups, participants without dopaminergic deficit had lower cognitive scores than participants with dopaminergic deficit and healthy controls at baseline. Group differences were not significant at follow-up; rather, impaired baseline olfaction predicted cognitive decline across all study participants.

CONCLUSIONS

Future studies are needed to assess whether the profile of motor and non-motor symptoms in patients without dopaminergic deficit, including olfaction, are deserving of their own syndrome, or whether individual patients may fit better under alternative, existing diagnoses.

Preoperative oral antibiotic bowel preparation in elective resectional colorectal surgery reduces rates of surgical site infections: a single-centre experience with a cost-effectiveness analysis

INTRODUCTION

Surgical site infections cause considerable postoperative morbidity and mortality. The aim of this study was to determine the effect on surgical site infection rates following introduction of a departmental oral antibiotic bowel preparation protocol.

METHODS

A prospective single-centre study was performed for elective colorectal resections between May 2016-April 2018; with a control group with mechanical bowel preparation and treatment group with oral antibiotic bowel preparation (neomycin and metronidazole) and mechanical bowel preparation. The primary outcome of surgical site infection and secondary outcomes of anastomotic leak, length of stay and mortality rate were analysed using Fisher's exact test and independent samples t-tests. A cost-effectiveness analysis was also performed.

RESULTS

A total of 311 patients were included; 156 in the mechanical bowel preparation group and 155 in the mechanical bowel preparation plus oral antibiotic bowel preparation group. The study included 180 (57.9%) men and 131 (42.1%) women with a mean age of 68 years. There was a significant reduction in surgical site infection rates (mechanical bowel preparation 16.0% vs mechanical bowel preparation plus oral antibiotic bowel preparation 4.5%; P = 0.001) and mean length of stay (mechanical bowel preparation 10.2 days vs mechanical bowel preparation plus oral antibiotic bowel preparation 8.2 days; P = 0.012). There was also a reduction in anastomotic leak and mortality rates. Subgroup analyses demonstrated significantly reduced surgical site infection rates in laparoscopic resections (P = 0.008). There was an estimated cost saving of £239.13 per patient and £37,065 for our institution over a one-year period.

CONCLUSION

Oral antibiotic bowel preparation is a feasible and cost-effective intervention shown to significantly reduce the rates of surgical site infection and length of stay in elective colorectal surgery.

B-26 Predictors of Cognitive Decline Over a 2-year Follow up: Olfaction and Scans Without Evidence of Dopaminergic Deficit Status (SWEDD)

Objective

Given the high discriminatory power of olfaction assessments in movement disorders, the current study sought to determine whether olfaction dysfunction differentially predicted cognitive decline in patients who have scans without evidence of dopaminergic deficit (SWEDD). Dopamine depletion is a major neuropathological feature of Parkinson’s disease (PD); however, 15% of patients with a clinical PD diagnosis have neuroimaging evidence of intact dopaminergic function. Recent work has suggested that patients with SWEDD are at a greater risk of cognitive impairment relative to those with PD.

Methods

Archival data were obtained from the Parkinson’s Progression Markers Initiative database. The total sample included three groups: PD (n = 401), SWEDD (n = 51), and HC (n = 175). Participants were categorized into non-impaired (-) or impaired (+) olfaction groups based on performance on the University of Pennsylvania Smell Identification Test, corrected for age and gender. Participants were administered the Montreal Cognitive Assessment twice and change scores were calculated to examine changes in cognition over time (baseline – two-year follow-up).

Results

A bootstrapped analysis of variance (ANOVA) revealed that the SWEDD+ group had lower MoCA scores than PD+ and HC+ groups at baseline (ps < .05). A bootstrapped ANOVA indicated that group differences were not significant at follow-up; rather, impaired baseline olfaction predicted cognitive decline across all study participants (p < .05), regardless of diagnosis.

Conclusions

Future studies are needed to assess whether the profile of motor and non-motor symptoms in SWEDD patients, including olfaction, is deserving of its own syndrome, or whether individual patients may fit better under alternative, existing diagnoses.

Neurocognitive profile of a man with Dandy-Walker malformation: Evidence of subtle cerebellar cognitive affective syndrome

Background: The Dandy-Walker Malformation (DWM) is a congenital birth malformation that is characterized by a triad of features: cerebellar dysgenesis, cystic dilation of the fourth ventricle, and an enlarged posterior fossa that displaces the dural sinuses and the tentorium. Despite this defining triad, clinical presentation can be highly heterogeneous in part due to severity of structural changes. To date, there been limited consideration of cognitive-behavioral symptoms of DWM in relation to nonmotor functions of the cerebellum, specifically cerebellar cognitive affective syndrome (CCAS).Method: In this case study, we describe the neuropsychological and behavioral profile of a 48-year-old man with DWM who was seen due to concerns, expressed solely by the patient's father, about his son's atypical housing, employment and social skills.Results: Neuropsychological test findings revealed high average intellect on standard intellectual measures (WAIS-IV), with stronger verbal (superior) than perceptual reasoning (average) skills. Across all cognitive domains, performance was generally within expectations, although bilateral fine motor skills were impaired. In contrast, he exhibited weaknesses on nontraditional neuropsychological measures assessing orbitofrontal-limbic circuitry, including reward sensitivity decision making and indices of threat-related emotional physiology.Conclusions: Through the use of traditional and nontraditional neuropsychological measures, subtle cognitive weaknesses in fronto-executive and affective regulation were illuminated and likely explain the patient's functional difficulties. Etiologically, these findings are consistent with the nonmotor functions of the cerebellum as described by CCAS.

Everyday functioning in Parkinson's disease: Evidence from the Revised-Observed Tasks of Daily Living (OTDL-R)

INTRODUCTION

Performance tasks are presumed to have greater validity than rating scales in assessing day-to-day behaviors in Parkinson's disease (PD). One such task is the revised Observed Tasks of Daily Living (OTDL-R), which has been used extensively in healthy older adults, and but not yet empirically examined in PD. Thus, the aims of the current study were to examine and determine the impact of cognitive, motor, and mood symptoms on OTDL-R performance in PD.

METHOD

Nineteen non-demented PD patients and 18 healthy older adults (HC) were administered measures of mood and cognitive functioning, and the OTDL-R (subtests include medication and telephone use, and medication management). Clinical severity of PD was assessed using the H&Y stage, UPDRS, and Schwab and England functional disability scores.

RESULTS

Mann Whitney U tests indicated the PD patients were significantly slower to complete the OTDL-R and performed worse on only the telephone use subtest, relative to the HC group. In the PD group, hierarchical regression analyses revealed memory, attention, and initiative/perseveration were uniquely associated with the financial management subtest, after controlling for motor severity (ps < .05). No other significant relationships were found.

CONCLUSIONS

PD patients were slower to complete the OTDL-R, but only less accurate on the telephone use subtest. Poor performance on the telephone use subtest may be related to motor severity, while poor performance on the financial management subtest was related to attention and working memory. Overall, the findings warrant future investigation to determine the validity and reliability of the OTDL-R in PD.

Do preoperative oral antibiotics increase Clostridium difficile infection rates? An analysis of 13 959 colectomy patients

AIM

The aim of this study was to determine whether or not preoperative oral antibiotic preparation (POAP) increases the rate of Clostridium difficile colitis (CDC) in patients undergoing colectomy.

METHOD

In 2015, data for colectomies had been collected prospectively and recorded in the targeted colectomy option of the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP). This was available for retrospective analysis. Data available for analysis included elective and emergency status, POAP, surgical approach, primary anastomosis and CDC status. The effect of POAP on CDC was analysed and risk adjusted for 14 separate preoperative variables.

RESULTS

In all, 13 959 adult patients underwent a colectomy in 2015 (POAP group 5311 and non- POAP group 8648). The overall rate of CDC in colectomy patients was 1.6% (227/13 959). On univariate analysis, CDC was significantly less common in the POAP group than in the non-POAP group (1.2% vs 1.9%, P = 0.003). Univariate analysis of a further 41 preoperative variables revealed 14 to be associated with CDC. However, after risk adjustment with these 14 variables, POAP lost its statistical significance (adjusted OR 0.902, 95% CI 0.584-1.486, P = 0.685). Only patients with pre-existing systemic inflammatory response syndrome appeared to be at increased risk of CDC (adjusted OR 2.154, 95% CI 1.139-4.074, P = 0.018).

CONCLUSION

At the very least this study suggests it is safe to use POAP in colectomy patients without increasing the rate of CDC unless they have pre-existing systemic inflammatory response syndrome.

Sleep disturbances and depression severity in patients with Parkinson's disease

OBJECTIVES

Parkinson's disease (PD) is a multisystem movement disorder associated with sleep disturbance and depression. Sleep disturbances and depression severity share a bidirectional association. This association may be greater in individuals who are more vulnerable to the deleterious consequences of sleep disturbance and depression severity. We investigated whether the association between sleep disturbances and depression severity is greater in patients with PD than in matched controls (MC).

MATERIALS AND METHODS

The study sample (N = 98) included 50 patients with idiopathic PD and 48 age-, race-, sex-, and education-matched controls. Sleep disturbances were assessed using self-reported total sleep time (TST) on the Pittsburgh Sleep Quality Index, the sleep item on the Beck Depression Inventory, 2nd ed. (BDI-II), and the Insomnia Severity Index total score. Depression severity was assessed using the BDI-II total score, excluding the sleep item. Spearman's correlations, chi-squared tests, and multiple regression were used to assess associations between sleep disturbances and depression severity in PD and MC. Fisher's Z transformation was used to test whether the association between sleep disturbances and depression severity was stronger in patients with PD.

RESULTS

Shorter TST, sleeping less than usual, and insomnia severity were associated with depression severity in the total sample, rs(94) = -0.35, p = .001; rs(71) = 0.51, p < .001; rs(78) = -0.47, p < .001; rs(98) = 0.46, p < .001, respectively. The association between shorter TST and depression severity was greater in patients with PD than it was in MC, p < .05.

CONCLUSION

Short TST may be an important marker, predictor, or consequence of depression severity in patients with Parkinson's disease.

Symptom Dimensions of Depression and Apathy and Their Relationship With Cognition in Parkinson's Disease

OBJECTIVES

Both depression and apathy, alone and in combination, have been shown to negatively affect cognition in patients with Parkinson's disease (PD). However, the influence of specific symptom dimensions of depression and apathy on cognition is not well understood. The current study investigated the relationship between symptom dimensions of depression and apathy, based on factors identified in Kirsch-Darrow et al. (2011), and memory and executive function in PD.

METHODS

A sample of 138 non-demented individuals with PD (mean age=64.51±7.43 years) underwent neuropsychological testing and completed the Beck Depression Inventory, 2nd Edition, and Apathy Scale. Separate hierarchical regression models examined the relationship between symptom dimensions of depression and apathy ("pure" depressive symptoms, "pure" apathy, loss of interest/pleasure [anhedonia], and somatic symptoms) and three cognitive domain composites: immediate verbal memory, delayed verbal memory, and executive function.

RESULTS

After adjusting for general cognitive status and the influence of the other symptom dimensions, "pure" depressive symptoms were negatively associated with the delayed verbal memory composite (p<.034) and somatic symptoms were positively associated with the executive function composite (p<.026). No symptom dimensions were significantly related to the immediate verbal memory composite.

CONCLUSIONS

Findings suggest that specific mood symptoms are associated with delayed verbal memory and executive function performance in non-demented patients with PD. Further research is needed to better understand possible mechanisms through which specific symptom dimensions of depression and apathy are associated with cognition in PD. (JINS, 2018, 24, 269-282).

Alterations of emotional reactivity following righttemporal lobectomy

To learn if a right temporal lobectomy altered a patient's autonomic and cognitive responses to aversive and appetitive pictures, we investigated a man whose right anterior temporal lobe and amygdala had been resected to remove an arteriovenous malformation. This patient revealed unusually low self-reports of arousal with a lack of heightened skin conductance responses to aversive pictures. For pleasant pictures, his self-reports of arousal and his physiological responses were similar to healthy men. This patient's responses are consistent with a bivalent model of emotional processing, with a right temporal lobectomy compromising the activation of his defensive action response system.

Safety and efficacy of dual-lead thalamic deep brain stimulation for patients with treatment-refractory multiple sclerosis tremor: a single-centre, randomised, single-blind, pilot trial

BACKGROUND

Efficacy in previous studies of surgical treatments of refractory multiple sclerosis tremor using lesioning or deep brain stimulation (DBS) has been variable. The aim of this study was to investigate the safety and efficacy of dual-lead thalamic DBS (one targeting the ventralis intermedius-ventralis oralis posterior nucleus border [the VIM lead] and one targeting the ventralis oralis anterior-ventralis oralis posterior border [the VO lead]) for the treatment of multiple sclerosis tremor.

METHODS

We did a single centre, single-blind, prospective, randomised pilot trial at the University of Florida Center for Movement Disorders and Neurorestoration clinic (Gainesville, FL, USA). We recruited adult patients with a clinical diagnosis of multiple sclerosis tremor refractory to previous medical therapy. Before surgery to implant both leads, we randomly assigned patients (1:1) to receive 3 months of optimised single-lead DBS-either VIM or VO. We did the randomisation with a computer-generated sequence, using three blocks of four patients, and independent members of the Center did the assignment. Patients and all clinicians other than the DBS programming nurse were masked to the choice of lead. Patients underwent surgery 1 month after their baseline visit for implantation of the dual lead DBS system. A pulse generator and two extension cables were implanted in a second surgery 3-4 weeks later. Patients then received an initial 3-month period of continuous stimulation of either the VIM or VO lead followed by blinded safety assessment of their tremor with the Tolosa-Fahn-Marin Tremor Rating Scale (TRS) during optimised VIM or VO lead stimulation at the end of the 3 months. After this visit, both leads were activated in all patients for an additional 3 months, and optimally programmed during serial visits as dictated by a prespecified programming algorithm. At the 6-month follow-up visit, TRS score was measured, and mood and psychological batteries were administered under four stimulation conditions: VIM on, VO on, both on, and both off (the order of testing was chosen by a computer-generated random sequence, assigned by independent members of the centre, and enacted by an unmasked DBS programming nurse). Each of four stimulation settings were tested over 4 consecutive days, with stimulation settings held constant for at least 12 h before testing. The primary outcome was change in mean total TRS score at the 6-month postoperative assessment with both leads activated, compared with the preoperative baseline mean TRS score. Analysis was by intention to treat. Safety was analysed in all patients who received the surgical implantation except in one patient who discontinued before the safety assessment. This trial is registered with ClinicalTrials.gov, number NCT00954421.

FINDINGS

Between Jan 16, 2007, and Dec 17, 2013, we enrolled 12 patients who were randomly assigned either to 3 initial months of VIM-only or VO-only stimulation. One patient from the VO-only group developed an infection necessitating DBS explantation, and was excluded from the assessment of the primary outcome. Compared with the mean baseline TRS score of 57·0 (SD 10·2), the mean score at 6 months decreased to 40·1 (17·6), -29·6% reduction; t=-0·28, p=0·03. Three of 11 patients did not respond to surgical intervention. One patient died suddenly 2 years after surgery, but this was judged to be unrelated to DBS implantation. Serious adverse events included a superficial wound infection in one patient that resolved with antibiotic therapy, and transient altered mental status and late multiple sclerosis exacerbation in another patient. The most common non-serious adverse events were headache and fatigue.

INTERPRETATION

Dual lead thalamic DBS might be a safe and effective option for improving severe, refractory multiple sclerosis tremor. Larger studies are necessary to show whether this technique is widely applicable, safe in the long-term, and effective in treating multiple sclerosis tremor or other severe tremor disorders.

FUNDING

US National Institutes of Health, the Cathy Donnellan, Albert E Einstein, and Birdie W Einstein Fund, and the William Merz Professorship.

Improved cognition while cycling in Parkinson's disease patients and healthy adults

Persons with Parkinson's disease (PD) are typically more susceptible than healthy adults to impaired performance when two tasks (dual task interference) are performed simultaneously. This limitation has by many experts been attributed to limitations in cognitive resources. Nearly all studies of dual task performance in PD employ walking or balance-based motor tasks, which are commonly impaired in PD. These tasks can be performed using a combination of one or two executive function tasks. The current study examined whether persons with PD would demonstrate greater dual task effects (DTEs) on cognition compared to healthy older adults (HOAs) during a concurrent cycling task. Participants with and without PD completed a battery of 12 cognitive tasks assessing visual and verbal processing in the following cognitive domains: speed of processing, controlled processing, working memory and executive function. Persons with PD exhibited impairments compared to healthy participants in select tasks (i.e., 0-back, 2-back and operation span). Further, both groups unexpectedly exhibited dual task facilitation of response times in visual tasks across cognitive domains, and improved verbal recall during an executive function task. Only one measure, 2-back, showed a speed-accuracy trade-off in the dual task. These results demonstrate that, when paired with a motor task in which they are not impaired, people with PD exhibit similar DTEs on cognitive tasks as HOAs, even when these task effects are facilitative. More generally, these findings demonstrate that pairing cognitive tasks with cycling may actually improve cognitive performance which may have therapeutic relevance to cognitive decline associated with aging and PD pathology.

Risk factors for anastomotic leakage after colorectal resection: a retrospective analysis of 17 518 patients

AIM

A large, prospectively collected, clinical database was analysed to determine the various pre- and intra-operative factors affecting anastomotic leakage (AL) in colorectal surgery.

METHOD

Data on 17 518 patients having a colorectal resection with anastomosis, taken from the 2013 American College of Surgeons National Surgical Quality Improvement Program database, were included in the study. Multivariable logistic regression analysis was carried out to identify risk-adjusted predictive factors for AL. Statistical significance was set at P < 0.05 and confidence intervals were reported at the 95% level.

RESULTS

The AL rate was 3.9% (687/17 518). Younger patients, male gender and an American Society of Anesthesiology (ASA) score of ≥ 3 (P < 0.001), smoking (P = 0.001), diabetes (P = 0.035), a preoperative serum albumin level of < 4 g/dl (P = 0.030), elective rectal cancer surgery (P = 0.024), emergency colectomy for bleeding (P = 0.013) and splenic flexure mobilization (P = 0.043) were associated with an increased risk of AL. Preoperative oral antibiotics (P < 0.001), right hemicolectomy (open or laparoscopic) and laparoscopic partial colectomy were associated with a reduced risk of AL compared with the entire group. Body mass index, preoperative chemotherapy, emergency surgery and mechanical bowel preparation were not related to AL.

CONCLUSION

In contrast to most studies, younger age was found to be an independent risk factor for AL. The risk for AL was lower with laparoscopic partial colectomy and open or laparoscopic right hemicolectomy. Preoperative oral antibiotic preparation significantly reduces the risk of AL and should be incorporated as a standard protocol.

The Parkinson's Active Living (PAL) Program

BACKGROUND

Apathy, one of the most common neuropsychiatric symptoms in Parkinson's disease (PD), has been associated with reduced daily functioning, cognition, treatment compliance, quality of life, and increased caregiver burden and distress, among other outcomes.

OBJECTIVES

The purpose of the present study was to develop and gather pilot data on the feasibility, acceptability, and efficacy of the Parkinson's Active Living (PAL) program, to our knowledge, the first behavioral treatment specifically designed to target apathy in patients with PD. The Parkinson's Active Living is a primarily telephone-based, 6-week activity scheduling and monitoring intervention that incorporates external cueing to target disease-related self-generational deficits to reduce levels of apathy in nondemented, highly apathetic patients with PD.

METHODS

Participants aged 44 to 86 years (mean = 66, SD [standard deviation] = 10.7) ranging in disease duration from <1 to 23 years with elevated apathy (Apathy Evaluation Scale >35) were enrolled in a 1-arm trial and tested at 3 time points (baseline, posttest, and 1-month follow-up).

RESULTS

Feasibility aspects (ie, acceptability, demand, implementation, practicality, adaptation, integration, and expansion) and efficacy of PAL program are reported. Matched pairs t tests showed a medium to large effect of treatment on patient apathy (52% showing ≥1 SD improvement), depression (33% showing ≥1 SD improvement), and quality of life at posttest, with improvements in apathy and depression maintained at follow-up.

CONCLUSIONS

The program may hold promise as an effective nonpharmacological intervention for apathy in PD. Implications and future directions are discussed. Randomized controlled trials are needed.