Association between stroke and psychosis across four nationally representative psychiatric epidemiological studies

BACKGROUND: Both stroke and psychosis are independently associated with high levels of disability. However, psychosis in the context of stroke has been under-researched. To date, there are no general population studies on their joint prevalence and association. AIMS: To estimate the joint prevalence of stroke and psychosis and their statistical association using nationally representative psychiatric epidemiology studies from two high-income countries (the UK and the USA) and two middle-income countries (Chile and Colombia) and, subsequently, in a combined-countries data-set. METHOD: Prevalences were calculated with 95% confidence intervals. Statistical associations between stroke and psychosis and between stroke and psychotic symptoms were tested using regression models. Overall estimates were calculated using an individual participant level meta-analysis on the combined-countries data-set. The analysis is available online as a computational notebook. RESULTS: The overall prevalence of probable psychosis in stroke was 3.81% (95% CI 2.34-5.82) and that of stroke in probable psychosis was 3.15% (95% CI 1.94-4.83). The odds ratio of the adjusted association between stroke and probable psychosis was 3.32 (95% CI 2.05-5.38). On the individual symptom level, paranoia, hallucinated voices and thought passivity delusion were associated with stroke in the unadjusted and adjusted analyses. CONCLUSIONS: Rates of association between psychosis and stroke suggest there is likely to be a high clinical need group who are under-researched and may be poorly served by existing services

Spectrum of impulse control behaviours in Parkinson's disease: pathophysiology and management.

Impulse control behaviours (ICBs) are a range of behaviours linked by their reward-based, repetitive natures. They can be precipitated in Parkinson's disease (PD) by dopamine replacement therapy, often with detrimental consequences for patients and caregivers. While now a well-recognised non-motor feature of treated PD, much remains unknown about the influence of risk factors, pathophysiological mechanisms, vulnerability factors for specific types of behaviour and the optimal management strategies. Imaging studies have identified structural and functional changes in striatal and prefrontal brain regions, among others. Gene association studies indicate a role for genetic predisposition to PD-ICB. Clinical observational studies have identified potential modifiable and non-modifiable risk factors. Psychological studies shed light on the neurocognitive domains implicated in PD-ICBs and identify psychosocial determinants that may perpetuate the cycle of impulsive and harm-avoidance behaviours. Based on these results, a range of pharmacological and non-pharmacological management strategies have been trialled in PD-ICBs with varying success. The purpose of this review is to update clinicians on the evidence around the pathophysiology of PD-ICB. We aim to translate our findings into an interpretable biopsychosocial model that can be applied to the clinical assessment and management of individual cases of PD-ICB

Predictors of Burden in Carers of Patients with Impulse Control Behaviors in Parkinson's Disease

Background: Impulse control behaviors (ICBs) are problematic, reward-based behaviors, affecting 15% to 35% of patients with Parkinson's disease. Evidence exists of increased carer burden as a result of these behaviors; however, little is known about the variables mediating this effect and their management. Objective: To identify factors predictive of carer burden in a cohort of patients with Parkinson's disease with ICBs to enable the development of targeted therapeutic interventions for carers. Methods: Data were collected from 45 patients with clinically significant ICBs and their carers, including levodopa equivalent daily dosage, motor and neuropsychiatric symptoms, cognitive function, and ICB severity. Carer burden was quantified by Zarit Burden Interview (ZBI). Univariate analyses were performed using the Spearman rank correlation. Linear regression was used to create a multivariate model for predicting ZBI. Results: Univariate analysis identified significant correlations between ZBI and patient total Neuropsychiatric Inventory (NPI) (rs = 0.50), 4 NPI subscores (agitation/aggression, rs = 0.41; depression/dysphoria, rs = 0.47; apathy/indifference, rs = 0.49; and irritability/lability, rs = 0.38; all P < 0.02), and the carer 28-item General Health Questionnaire (GHQ-28) (rs = 0.52, P < 0.0005). Multivariate linear regression retained total NPI and GHQ-28 scores and were collectively predictive of 36.6% of the variance in the ZBI. Conclusions: Our study suggests that depressive symptoms and aspects of executive dysfunction (apathy and disinhibition) in the patient are potential drivers of carer burden in patients with ICBs. Such findings suggest the presence of executive difficulties and/or mood disturbance should point the clinician to inquire about burden in the caring role and encourage the carer to seek help for any of their own general health problems, which may compound carer burden

Sandwich Model of Educational Upgrading in Ghana: A Transitional Challenge in Disguise

The study investigated transitional challenges among undergraduate (bachelor of education) sandwich students. Adopting the descriptive survey design, a census population of 651 was used. Sanagavarapu, Abraham and Taylor’s (2018) TWHAS was used for data collection. The data was analysed using frequency counts and MANOVA. The study revealed that 59.6% of the students experienced difficulty in balancing family commitments with studies, 77.4% found it difficult to exercise, 61.0% found it difficult meeting up with friends and 73.3% found it difficult balancing financial commitments. Again, 45.2% of the students rarely experienced misunderstanding, while 25.0% were concerned about what others would say about them, 29.2% were concerned about the language barrier, 75.7% were concerned about their inability to explain their problems but 81.9% were not afraid seeking support from colleagues. More so, females experienced transitional challenges more than males. It is recommended for managers of the programmes to counsel students so as to control the effects of the challenges

Association between stroke and psychosis across four nationally representative psychiatric epidemiological studies

Background Both stroke and psychosis are independently associated with high levels of disability. However, psychosis in the context of stroke has been under-researched. To date, there are no general population studies on their joint prevalence and association. Aims To estimate the joint prevalence of stroke and psychosis and their statistical association using nationally representative psychiatric epidemiology studies from two high-income countries (the UK and the USA) and two middle-income countries (Chile and Colombia) and, subsequently, in a combined-countries data-set. Method Prevalences were calculated with 95% confidence intervals. Statistical associations between stroke and psychosis and between stroke and psychotic symptoms were tested using regression models. Overall estimates were calculated using an individual participant level meta-analysis on the combined-countries data-set. The analysis is available online as a computational notebook. Results The overall prevalence of probable psychosis in stroke was 3.81% (95% CI 2.34–5.82) and that of stroke in probable psychosis was 3.15% (95% CI 1.94–4.83). The odds ratio of the adjusted association between stroke and probable psychosis was 3.32 (95% CI 2.05–5.38). On the individual symptom level, paranoia, hallucinated voices and thought passivity delusion were associated with stroke in the unadjusted and adjusted analyses. Conclusions Rates of association between psychosis and stroke suggest there is likely to be a high clinical need group who are under-researched and may be poorly served by existing services

Loop operators and S-duality from curves on Riemann surfaces

We study Wilson-'t Hooft loop operators in a class of N=2 superconformal field theories recently introduced by Gaiotto. In the case that the gauge group is a product of SU(2) groups, we classify all possible loop operators in terms of their electric and magnetic charges subject to the Dirac quantization condition. We then show that this precisely matches Dehn's classification of homotopy classes of non-self-intersecting curves on an associated Riemann surface--the same surface which characterizes the gauge theory. Our analysis provides an explicit prediction for the action of S-duality on loop operators in these theories which we check against the known duality transformation in several examples.Comment: 41 page

Impulse control disorders in Parkinson and RBD:a longitudinal study of severity.

Objective To describe the prevalence, natural history, and risk factors for impulse control behaviors (ICBs) among people with Parkinson disease (PD), those with REM sleep behavior disorder (RBD), and controls. Methods Participants with early PD (within 3.5 years of diagnosis), those with RBD, and controls were clinically phenotyped and screened for ICBs longitudinally (with the Questionnaire for Impulsivity in Parkinson's Disease). ICB-positive individuals were invited for a semistructured interview, repeated 1 year later. The severity of the ICB was assessed with the Parkinson's Impulse Control Scale. Multiple imputation and regression models were used to estimate ICB prevalence and associations. Results Data from 921 cases of PD at baseline, 768 cases at 18 months, and 531 cases at 36 months were included, with 21% to 25% screening positive for ICBs at each visit. Interviews of ICB screen–positive individuals revealed that 10% met formal criteria for impulse control disorders (ICD), while 33% had subsyndromal ICD (ICB symptoms without reaching the formal diagnostic criteria for ICD). When these data were combined through the use of multiple imputation, the prevalence of PD-ICB was estimated at 19.1% (95% confidence interval 10.1–28.2). On follow-up, 24% of cases of subsyndromal ICD had developed full symptoms of an ICD. PD-ICD was associated with dopamine agonist use, motor complications, and apathy but not PD-RBD. ICD prevalence in the RBD group (1%) was similar to that in controls (0.7%). Conclusions ICBs occur in 19.1% of patients with early PD, many persisting or worsening over time. RBD is not associated with increased ICD risk. Psychosocial drivers, including mood and support networks, affect severity

Personality and addictive behaviours in early Parkinson's disease and REM sleep behaviour disorder

INTRODUCTION: Changes in personality have been described in Parkinson's disease (PD), with suggestion that those with established disease tend to be risk averse with a disinclination for addictive behaviour. However, little is known about the earliest and prodromal stages. Personality and its relationship with addictive behaviours can help answer important questions about the mechanisms underlying PD and addiction. METHODS: 941 population-ascertained PD subjects within 3.5 years of diagnosis, 128 patients with rapid eye movement sleep behaviour disorder (RBD) and 292 control subjects were fully characterised for motor symptoms, non-motor symptoms and across the following 5 personality domains: 1) neuroticism 2) extraversion 3) conscientiousness 4) agreeableness 5) openness using the Big Five Inventory. RESULTS: Patients with early PD were more neurotic (p < 0.001), less extraverted (p < 0.001) and less open than controls (p < 0.001). RBD subjects showed the same pattern of being more neurotic (p < 0.001), less extraverted (p = 0.03) and less open (p < 0.001). PD patients had smoked less (p = 0.02) and drunk less alcohol (p = 0.03) than controls, but caffeine beverage consumption was similar. Being more extraverted (p < 0.001), more open (p < 0.001), and less neurotic (p < 0.001) predicted higher alcohol use, while being more extravert (p = 0.007) and less agreeable (p < 0.001) was associated with smoking more. CONCLUSIONS: A similar pattern of personality changes is seen in PD and RBD compared to a control population. Personality characteristics were associated with addictive behaviours, suggestive of a common link, but the lower rates of addictive behaviours before and after the onset of motor symptoms in PD persisted after accounting for personality

Interlaboratory study for coral Sr/Ca and other element/Ca ratio measurements

The Sr/Ca ratio of coral aragonite is used to reconstruct past sea surface temperature (SST). Twentyone laboratories took part in an interlaboratory study of coral Sr/Ca measurements. Results show interlaboratory bias can be significant, and in the extreme case could result in a range in SST estimates of 7°C. However, most of the data fall within a narrower range and the Porites coral reference material JCp- 1 is now characterized well enough to have a certified Sr/Ca value of 8.838 mmol/mol with an expanded uncertainty of 0.089 mmol/mol following International Association of Geoanalysts (IAG) guidelines. This uncertainty, at the 95% confidence level, equates to 1.5°C for SST estimates using Porites, so is approaching fitness for purpose. The comparable median within laboratory error is <0.5°C. This difference in uncertainties illustrates the interlaboratory bias component that should be reduced through the use of reference materials like the JCp-1. There are many potential sources contributing to biases in comparative methods but traces of Sr in Ca standards and uncertainties in reference solution composition can account for half of the combined uncertainty. Consensus values that fulfil the requirements to be certified values were also obtained for Mg/Ca in JCp-1 and for Sr/Ca and Mg/Ca ratios in the JCt-1 giant clam reference material. Reference values with variable fitness for purpose have also been obtained for Li/Ca, B/Ca, Ba/Ca, and U/Ca in both reference materials. In future, studies reporting coral element/Ca data should also report the average value obtained for a reference material such as the JCp-1