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Negative symptoms are a key feature of several psychiatric disorders. Difficulty identifying common neurobiological mechanisms that cut across diagnostic boundaries might result from equifinality (i.e., multiple mechanistic pathways to the same clinical profile), both within and across disorders. This study used a data-driven approach to identify unique subgroups of participants with distinct reward processing profiles to determine which profiles predicted negative symptoms.
Methods
Participants were a transdiagnostic sample of youth from a multisite study of psychosis risk, including 110 individuals at clinical high-risk for psychosis (CHR; meeting psychosis-risk syndrome criteria), 88 help-seeking participants who failed to meet CHR criteria and/or who presented with other psychiatric diagnoses, and a reference group of 66 healthy controls. Participants completed clinical interviews and behavioral tasks assessing four reward processing constructs indexed by the RDoC Positive Valence Systems: hedonic reactivity, reinforcement learning, value representation, and effort–cost computation.
Results
k-means cluster analysis of clinical participants identified three subgroups with distinct reward processing profiles, primarily characterized by: a value representation deficit (54%), a generalized reward processing deficit (17%), and a hedonic reactivity deficit (29%). Clusters did not differ in rates of clinical group membership or psychiatric diagnoses. Elevated negative symptoms were only present in the generalized deficit cluster, which also displayed greater functional impairment and higher psychosis conversion probability scores.
Conclusions
Contrary to the equifinality hypothesis, results suggested one global reward processing deficit pathway to negative symptoms independent of diagnostic classification. Assessment of reward processing profiles may have utility for individualized clinical prediction and treatment.
Accurate diagnosis of bipolar disorder (BPD) is difficult in clinical practice, with an average delay between symptom onset and diagnosis of about 7 years. A depressive episode often precedes the first manic episode, making it difficult to distinguish BPD from unipolar major depressive disorder (MDD).
Aims
We use genome-wide association analyses (GWAS) to identify differential genetic factors and to develop predictors based on polygenic risk scores (PRS) that may aid early differential diagnosis.
Method
Based on individual genotypes from case–control cohorts of BPD and MDD shared through the Psychiatric Genomics Consortium, we compile case–case–control cohorts, applying a careful quality control procedure. In a resulting cohort of 51 149 individuals (15 532 BPD patients, 12 920 MDD patients and 22 697 controls), we perform a variety of GWAS and PRS analyses.
Results
Although our GWAS is not well powered to identify genome-wide significant loci, we find significant chip heritability and demonstrate the ability of the resulting PRS to distinguish BPD from MDD, including BPD cases with depressive onset (BPD-D). We replicate our PRS findings in an independent Danish cohort (iPSYCH 2015, N = 25 966). We observe strong genetic correlation between our case–case GWAS and that of case–control BPD.
Conclusions
We find that MDD and BPD, including BPD-D are genetically distinct. Our findings support that controls, MDD and BPD patients primarily lie on a continuum of genetic risk. Future studies with larger and richer samples will likely yield a better understanding of these findings and enable the development of better genetic predictors distinguishing BPD and, importantly, BPD-D from MDD.
Toward the end of the first millennium ad, a burgeoning class of secular elites emerged throughout western Europe who developed local power centres to denote their prestige. Seigneurial investment was prioritised towards residences, as well as churches and chapels, the two elements often paired into single places in the landscape. In England, our understanding of these complexes is limited due to scant excavated evidence and skewed by the impact of the Norman Conquest, after which castles became the dominant form of aristocratic site. Previous approaches have often fetishised defensibility and promoted notions of national exceptionalism, but a more meaningful understanding of these places can be gained by adopting a broad chronological and thematic remit. Drawing upon the results of the AHRC-funded research project ‘Where Power Lies’, this paper offers a foundational evaluation of the landscape evidence for lordly centres, presenting data on their distribution in two regions, complemented by results from intensive investigation of case study locations (Bosham, West Sussex and Hornby, North Yorkshire). This allows a wider range of material signatures from lordly centres to be characterised, resulting in greater comprehension of how elites in England shaped and experienced a Europe-wide phenomenon.
Anxiety is a common comorbid feature of late-life depression (LLD) and is associated with poorer global cognitive functioning independent of depression severity. However, little is known about whether comorbid anxiety is associated with a domain-specific pattern of cognitive dysfunction. We therefore examined group differences (LLD with and without comorbid anxiety) in cognitive functioning performance across multiple domains.
Method:
Older adults with major depressive disorder (N = 228, ages 65–91) were evaluated for anxiety and depression severity, and cognitive functioning (learning, memory, language, processing speed, executive functioning, working memory, and visuospatial functioning). Ordinary least squares regression adjusting for age, sex, education, and concurrent depression severity examined anxiety group differences in performance on tests of cognitive functioning.
Results:
Significant group differences emerged for confrontation naming and visuospatial functioning, as well as for verbal fluency, working memory, and inhibition with lower performance for LLD with comorbid anxiety compared to LLD only, controlling for depression severity.
Conclusions:
Performance patterns identified among older adults with LLD and comorbid anxiety resemble neuropsychological profiles typically seen in neurodegenerative diseases of aging. These findings have potential implications for etiological considerations in the interpretation of neuropsychological profiles.
When a viscous fluid partially fills a Hele-Shaw channel, and is pushed by a pressure difference, the fluid interface is unstable due to the Saffman–Taylor instability. We consider the evolution of a fluid region of finite extent, bounded between two interfaces, in the limit that the interfaces are close, that is, when the fluid region is a thin liquid filament separating two gases of different pressure. In this limit, we derive a second-order ‘thin-filament’ model that describes the normal velocity of the filament centreline, and evolution of the filament thickness, as functions of the thickness, centreline curvature and their derivatives. We show that the second-order terms in this model, that include the effect of transverse flow along the filament, are necessary to regularise the instability. Numerical simulation of the thin-filament model is shown to be in accordance with level-set computations of the complete two-interface model. Solutions ultimately evolve to form a bubble of rapidly increasing radius and decreasing thickness.
Edited by
William J. Brady, University of Virginia,Mark R. Sochor, University of Virginia,Paul E. Pepe, Metropolitan EMS Medical Directors Global Alliance, Florida,John C. Maino II, Michigan International Speedway, Brooklyn,K. Sophia Dyer, Boston University Chobanian and Avedisian School of Medicine, Massachusetts
Mass gatherings create challenges for timely and efficient medical response. Compounded by exceptional noise from cheering crowds and ambient entertainment, compacted audiences form predictable barriers to patient sightings and access. Timely access also may be complicated by steep arena stairwells or poorly-defined locations along a longitudinal raceway, parade, or beachside festival. On-scene responders often encounter fixed barricades, inebriated crowds, obtrusive noise, and relative distances from on-site medical aid centers. Very often, potentially ill or injured persons are adamantly set against leaving their coveted position in the audience having purchased expensive tickets, traveled far and awaited many months, or even years, to be there. Once retrieved, patients need to be conveyed with protective measures and evaluated appropriately despite resource-limited settings and often pervasive heat, humidity and intoxication. Accordingly, patient identification, intra-site retrieval, evacuation, tracking, and communications need to be optimally planned and well-coordinated to mitigate these challenges. Recent experiences have provided evolving insights into best practices for mass gathering medical professionals. Many are addressed within this discussion including definitions for reportable patients, use of spotters and geospatial applications, coordinated tandem response with security personnel, dedicated record-keepers at medical care sites and electronic tracking devices for vulnerable populations and even entire audiences.
Late-life depression (LLD) is common and frequently co-occurs with neurodegenerative diseases of aging. Little is known about how heterogeneity within LLD relates to factors typically associated with neurodegeneration. Varying levels of anxiety are one source of heterogeneity in LLD. We examined associations between anxiety symptom severity and factors associated with neurodegeneration, including regional brain volumes, amyloid beta (Aβ) deposition, white matter disease, cognitive dysfunction, and functional ability in LLD.
Participants and Measurements:
Older adults with major depression (N = 121, Ages 65–91) were evaluated for anxiety severity and the following: brain volume (orbitofrontal cortex [OFC], insula), cortical Aβ standardized uptake value ratio (SUVR), white matter hyperintensity (WMH) volume, global cognition, and functional ability. Separate linear regression analyses adjusting for age, sex, and concurrent depression severity were conducted to examine associations between anxiety and each of these factors. A global regression analysis was then conducted to examine the relative associations of these variables with anxiety severity.
Results:
Greater anxiety severity was associated with lower OFC volume (β = −68.25, t = −2.18, p = .031) and greater cognitive dysfunction (β = 0.23, t = 2.46, p = .016). Anxiety severity was not associated with insula volume, Aβ SUVR, WMH, or functional ability. When examining the relative associations of cognitive functioning and OFC volume with anxiety in a global model, cognitive dysfunction (β = 0.24, t = 2.62, p = .010), but not OFC volume, remained significantly associated with anxiety.
Conclusions:
Among multiple factors typically associated with neurodegeneration, cognitive dysfunction stands out as a key factor associated with anxiety severity in LLD which has implications for cognitive and psychiatric interventions.
Several hypotheses may explain the association between substance use, posttraumatic stress disorder (PTSD), and depression. However, few studies have utilized a large multisite dataset to understand this complex relationship. Our study assessed the relationship between alcohol and cannabis use trajectories and PTSD and depression symptoms across 3 months in recently trauma-exposed civilians.
Methods
In total, 1618 (1037 female) participants provided self-report data on past 30-day alcohol and cannabis use and PTSD and depression symptoms during their emergency department (baseline) visit. We reassessed participant's substance use and clinical symptoms 2, 8, and 12 weeks posttrauma. Latent class mixture modeling determined alcohol and cannabis use trajectories in the sample. Changes in PTSD and depression symptoms were assessed across alcohol and cannabis use trajectories via a mixed-model repeated-measures analysis of variance.
Results
Three trajectory classes (low, high, increasing use) provided the best model fit for alcohol and cannabis use. The low alcohol use class exhibited lower PTSD symptoms at baseline than the high use class; the low cannabis use class exhibited lower PTSD and depression symptoms at baseline than the high and increasing use classes; these symptoms greatly increased at week 8 and declined at week 12. Participants who already use alcohol and cannabis exhibited greater PTSD and depression symptoms at baseline that increased at week 8 with a decrease in symptoms at week 12.
Conclusions
Our findings suggest that alcohol and cannabis use trajectories are associated with the intensity of posttrauma psychopathology. These findings could potentially inform the timing of therapeutic strategies.
During the COVID-19 pandemic, Kentucky prohibited elective medical procedures from 3/18/2020-4/27/2020. We sought to determine if cessation of elective procedures in Kentucky during the COVID-19 pandemic resulted in a decrease in the proportion of rarely appropriate outpatient transthoracic echocardiograms interpreted at the open echocardiography lab at Norton Children’s Hospital.
Methods:
A retrospective chart review was conducted comparing proportions of rarely appropriate outpatient paediatric transthoracic echocardiograms performed pre-COVID (3/21/2019-4/28/2019) and during COVID (3/19/2020-4/27/2020). Transthoracic echocardiogram indication was determined by chart review and echocardiogram reports. Indication appropriateness was evaluated using paediatric appropriate use criteria for initial outpatient transthoracic echocardiogram or CHD follow-up as applicable.
Results:
Of transthoracic echocardiograms pre-COVID, 100 (37.7%) were rarely appropriate versus 18 (20.2%) during COVID. Pre-COVID, paediatric cardiologists tended to order fewer rarely appropriate transthoracic echocardiograms than paediatricians (35.9% versus 46.4%), although this difference was not statistically significant. Cardiologists ordered the majority of outpatient transthoracic echocardiograms during COVID (77/89, 86.5%), limiting the ability to compare transthoracic echocardiogram indications by provider type. There was no significant difference in diagnostic yield of initial outpatient transthoracic echocardiograms with (13.0%) abnormal studies pre-COVID versus 7 (15.5%) during COVID.
Conclusion:
While elective procedures were prohibited in Kentucky during the COVID-19 pandemic, a decrease in the proportion of rarely appropriate outpatient paediatric transthoracic echocardiograms was observed. There was no significant difference in diagnostic yield of initial outpatient transthoracic echocardiograms between time periods, suggesting that clinically significant echocardiogram findings were still detected despite more prudent utilisation of echocardiography during this time.
The rift setting of eastern Africa preserves exceptional records of mammalian (including hominin) fossils and archeology. The Afar region is host to multiple deposits with sediments ranging in age from>9 Ma to the present (Chorowicz, 2005; Katoh et al., 2016) and plays a major role in our understanding of human origins. The Gona project area contains fossiliferous deposits that span ca. 6.3 to <0.15 Ma (Quade et al., 2008); the duration of this record means that it can make a distinct contribution to understanding the environmental context for human evolution within the Afar and in eastern Africa (Figures 17.1 and 17.2). The primary units at Gona include the late Miocene Adu-Asa Formation, which contains fossils of Ardipithecus kaddaba; the early Pliocene Sagantole Formation with fossils of Ardipithecus ramidus; the mid- to late-Pliocene Hadar Formation; and the Busidima Formation (ca. 2.7 Ma to <0.15 Ma), which contains a record of the earliest Oldowan stone tools, fossils of Homo erectus, and Acheulean artifacts (Figure 17.2).
VISITORS to the Cathedral Church of St Peter at Exeter may not know it, but as they proceed along the nave, going deeper and deeper into this forest-like space, they are approaching an opening – a passageway between the Wessex of Kings Ine and Æthelheard and the southwest Pacific island of Nukapu in the days of Chiefs Moto and Taula. This transglobal and trans-temporal portal stands on the north side of the nave and is known as the Martyrs’ Pulpit. To casual tourists, it shows no signs of being a link between two hemispheres; it is well disguised as a fine example of Victorian Gothic Revival. But a few facts about the relations that went into the making of this object cause it to appear differently. It is the visual epitome of a grand comparison, a network of associations that, in the mid nineteenth century, opened mutually generating channels of communication between Northern Europe and the Pacific.
Designed by Sir George Gilbert Scott, the Martyrs’ Pulpit was erected in 1877. It is decorated with images of six men honoured by Christians as having died for the sake of the gospel (Fig. 9.1). Three corner niches depict biblical martyrs: St John the Baptist, St Stephen, and St Paul. Three lateral reliefs portray scenes in the lives of three British martyrs. On one side, St Alban prays as the executioner raises his sword. On the opposite side, St Boniface sails from Britain to preach on the Continent, where he will die at the hands of the Frisians in 754. But the front of the pulpit bears the main tableau (Fig. 9.2). Here, by European reckoning, it is 20 September 1871 on Nukapu, a small island roughly fourteen hundred miles northeast of Australia. In a composition evocative of the descent from the cross, three Nukapuans lower the body of Bishop John Coleridge Patteson, wrapped in a palm leaf mat, into a canoe. Soon, crew from the mission vessel – the Southern Cross, represented in the distance under sail – will send the ship’s boat to collect their murdered leader.
Clearly, this object is staging many simultaneous comparisons, not only among the six martyrs depicted but also pointing back to Christ and encompassing all martyrs, past and future; carved around the base of the reliefs are the words of the Te Deum, ‘[t]he noble army of martyrs praise Thee’.
Response to lithium in patients with bipolar disorder is associated with clinical and transdiagnostic genetic factors. The predictive combination of these variables might help clinicians better predict which patients will respond to lithium treatment.
Aims
To use a combination of transdiagnostic genetic and clinical factors to predict lithium response in patients with bipolar disorder.
Method
This study utilised genetic and clinical data (n = 1034) collected as part of the International Consortium on Lithium Genetics (ConLi+Gen) project. Polygenic risk scores (PRS) were computed for schizophrenia and major depressive disorder, and then combined with clinical variables using a cross-validated machine-learning regression approach. Unimodal, multimodal and genetically stratified models were trained and validated using ridge, elastic net and random forest regression on 692 patients with bipolar disorder from ten study sites using leave-site-out cross-validation. All models were then tested on an independent test set of 342 patients. The best performing models were then tested in a classification framework.
Results
The best performing linear model explained 5.1% (P = 0.0001) of variance in lithium response and was composed of clinical variables, PRS variables and interaction terms between them. The best performing non-linear model used only clinical variables and explained 8.1% (P = 0.0001) of variance in lithium response. A priori genomic stratification improved non-linear model performance to 13.7% (P = 0.0001) and improved the binary classification of lithium response. This model stratified patients based on their meta-polygenic loadings for major depressive disorder and schizophrenia and was then trained using clinical data.
Conclusions
Using PRS to first stratify patients genetically and then train machine-learning models with clinical predictors led to large improvements in lithium response prediction. When used with other PRS and biological markers in the future this approach may help inform which patients are most likely to respond to lithium treatment.
This chapter introduces readers to the use of time-varying effect modeling (TVEM), a statistical tool for capturing dynamic changes over time, as applied to the study of substance use disorder recovery processes. The chapter presents an empirical demonstration of using TVEM to examine the effect of an intervention, Recovery Management Checkups (RMCs), on substance use and key features of the ongoing process of recovery (life satisfaction, cognitive avoidance, self-efficacy) as a continuous function of time. The example application data come from the Early Re-Intervention experiment of 446 adults from a large addiction treatment agency who were randomly assigned to receive RMCs or an assessment control. Given the time-varying nature of the effect of the RMC on recovery outcomes and the differential patterns observed by type of outcome, TVEM may be a viable option in lieu of or in addition to using common metrics of “treatment success.” SAS syntax is provided.
To achieve the elimination of the hepatitis C virus (HCV), sustained and sufficient levels of HCV testing is critical. The purpose of this study was to assess trends in testing and evaluate the effectiveness of strategies to diagnose people living with HCV. Data were from 12 primary care clinics in Victoria, Australia, that provide targeted services to people who inject drugs (PWID), alongside general health care. This ecological study spanned 2009–2019 and included analyses of trends in annual numbers of HCV antibody tests among individuals with no previous positive HCV antibody test recorded and annual test yield (positive HCV antibody tests/all HCV antibody tests). Generalised linear models estimated the association between count outcomes (HCV antibody tests and positive HCV antibody tests) and time, and χ2 test assessed the trend in test yield. A total of 44 889 HCV antibody tests were conducted 2009–2019; test numbers increased 6% annually on average [95% confidence interval (CI) 4–9]. Test yield declined from 2009 (21%) to 2019 (9%) (χ2P = <0.01). In more recent years (2013–2019) annual test yield remained relatively stable. Modest increases in HCV antibody testing and stable but high test yield within clinics delivering services to PWID highlights testing strategies are resulting in people are being diagnosed however further increases in the testing of people at risk of HCV or living with HCV may be needed to reach Australia's HCV elimination goals.
The classical model for studying one-phase Hele-Shaw flows is based on a highly nonlinear moving boundary problem with the fluid velocity related to pressure gradients via a Darcy-type law. In a standard configuration with the Hele-Shaw cell made up of two flat stationary plates, the pressure is harmonic. Therefore, conformal mapping techniques and boundary integral methods can be readily applied to study the key interfacial dynamics, including the Saffman–Taylor instability and viscous fingering patterns. As well as providing a brief review of these key issues, we present a flexible numerical scheme for studying both the standard and nonstandard Hele-Shaw flows. Our method consists of using a modified finite-difference stencil in conjunction with the level-set method to solve the governing equation for pressure on complicated domains and track the location of the moving boundary. Simulations show that our method is capable of reproducing the distinctive morphological features of the Saffman–Taylor instability on a uniform computational grid. By making straightforward adjustments, we show how our scheme can easily be adapted to solve for a wide variety of nonstandard configurations, including cases where the gap between the plates is linearly tapered, the plates are separated in time, and the entire Hele-Shaw cell is rotated at a given angular velocity.
Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.
Aims
To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.
Method
Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.
Results
Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = −0.34 years, s.e. = 0.08), major depression (β = −0.34 years, s.e. = 0.08), schizophrenia (β = −0.39 years, s.e. = 0.08), and educational attainment (β = −0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.
Conclusions
AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.
This chapter presents an overview of the nature, assessment, and treatment of obsessive-compulsive and related disorders (OCRD), including obsessive-compulsive disorder (OCD), body dysmorphic disorder (BDD), hoarding disorder (HD), hair-pulling disorder (HPD), and skin-picking disorder (SPD). Specifically, we review the DSM-V diagnostic criteria, epidemiology and impact, clinical features and course, and etiological insights for each of these disorders in turn. Next, we discuss key points to consider when making a differential diagnosis with disorders outside the OCRD category. From there, we turn to a discussion of the assessment and treatment of these disorders using pharmacological, cognitive-behavioral, and neuromodulation interventions. Future directions in the research on OCRDs then follows.
Nearly three times as many people detained in a jail have a serious mental illness (SMI) when compared to community samples. Once an individual with SMI gets involved in the criminal justice system, they are more likely than the general population to stay in the system, face repeated incarcerations, and return to prison more quickly when compared to their nonmentally ill counterparts.