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In addressing questions posed by Marcus and Nagel, the authors call attention to the variegated nature of psychopathy, highlighting its symptom subdimensions and differing manifest expressions (variants/subtypes). They discuss how the constructs of the triarchic model can be viewed both as phenotypic characteristics and as biobehavioral dispositions, and consider how these alternative perspectives can be helpful for clarifying what psychopathy “is” and “how” it develops. In responding to Lynam, they consider the sources of his criticisms as well as their content – focusing in particular on his preference for the five-factor trait model (FFM) as a descriptive framework, and the priority he places on psychopathy in its aggressive-criminal form. The authors discuss how the triarchic model complements the FFM descriptive approach through its emphasis on biobehavioral systems/processes and its ability to account for other variants of psychopathy.
There is lack of Cameroonian adult neuropsychological (NP) norms, limited knowledge concerning HIV-associated neurocognitive disorders in Sub-Saharan Africa, and evidence of differential inflammation and disease progression based on viral subtypes. In this study, we developed demographically corrected norms and assessed HIV and viral genotypes effects on attention/working memory (WM), learning, and memory.
We administered two tests of attention/WM [Paced Auditory Serial Addition Test (PASAT)-50, Wechsler Memory Scale (WMS)-III Spatial Span] and two tests of learning and memory [Brief Visuospatial Memory Test-Revised (BVMT-R), Hopkins Verbal Learning Test-Revised (HVLT-R)] to 347 HIV+ and 395 seronegative adult Cameroonians. We assessed the effects of viral factors on neurocognitive performance.
Compared to controls, people living with HIV (PLWH) had significantly lower T-scores on PASAT-50 and attention/WM summary scores, on HVLT-R total learning and learning summary scores, on HVLT-R delayed recall, BVMT-R delayed recall and memory summary scores. More PLWH had impairment in attention/WM, learning, and memory. Antiretroviral therapy (ART) and current immune status had no effect on T-scores. Compared to untreated cases with detectable viremia, untreated cases with undetectable viremia had significantly lower (worse) T-scores on BVMT-R total learning, BVMT-R delayed recall, and memory composite scores. Compared to PLWH infected with other subtypes (41.83%), those infected with HIV-1 CRF02_AG (58.17%) had higher (better) attention/WM T-scores.
PLWH in Cameroon have impaired attention/WM, learning, and memory and those infected with CRF02_AG viruses showed reduced deficits in attention/WM. The first adult normative standards for assessing attention/WM, learning, and memory described, with equations for computing demographically adjusted T-scores, will facilitate future studies of diseases affecting cognitive function in Cameroonians.
The hypoactive, hyperactive, and mixed subtypes of delirium differently impact patient management and prognosis, yet the evidence remains sparse. Therefore, we examined the outcome of varying management strategies in the subtypes of delirium.
In this observational cohort study, 602 patients were managed for delirium over 20 days with the following strategies: supportive care alone or in combination with psychotropics, single, dual, or triple+ psychotropic regimens. Cox regression models were calculated for time to remission and benefit rates (BRs) of management strategies.
Generally, the mixed subtype of delirium caused more severe and persistent delirium, and the hypoactive subtype was more persistent than the hyperactive subtype. The subtypes of delirium were similarly predictive for mortality (P = 0.697) and transfer to inpatient psychiatric care (P = 0.320). In the mixed subtype, overall, psychotropic drugs were administered more often (P = 0.016), and particularly triple+ regimens were administered more commonly compared to hypoactive delirium (P = 0.007). Patients on supportive care benefited most, whereas those on triple+ regimens did worst in terms of remission in all groups of hypoactive, hyperactive, and mixed subtypes (BR: 4.59, CI 2.01–10.48; BR: 4.59, CI 1.76–31.66; BR: 3.36, CI 1.73–6.52; all P < 0.05).
Significance of results
The mixed subtype was more persistent to management than the hypoactive and hyperactive subtypes. Delirium management remains controversial and, generally, supportive care benefited patients most. Psychopharmacological management for delirium requires careful choosing of and limiting the number of psychotropics.
Substantial clinical heterogeneity of major depressive disorder (MDD) suggests it may group together individuals with diverse aetiologies. Identifying distinct subtypes should lead to more effective diagnosis and treatment, while providing more useful targets for further research. Genetic and clinical overlap between MDD and schizophrenia (SCZ) suggests an MDD subtype may share underlying mechanisms with SCZ.
The present study investigated whether a neurobiologically distinct subtype of MDD could be identified by SCZ polygenic risk score (PRS). We explored interactive effects between SCZ PRS and MDD case/control status on a range of cortical, subcortical and white matter metrics among 2370 male and 2574 female UK Biobank participants.
There was a significant SCZ PRS by MDD interaction for rostral anterior cingulate cortex (RACC) thickness (β = 0.191, q = 0.043). This was driven by a positive association between SCZ PRS and RACC thickness among MDD cases (β = 0.098, p = 0.026), compared to a negative association among controls (β = −0.087, p = 0.002). MDD cases with low SCZ PRS showed thinner RACC, although the opposite difference for high-SCZ-PRS cases was not significant. There were nominal interactions for other brain metrics, but none remained significant after correcting for multiple comparisons.
Our significant results indicate that MDD case-control differences in RACC thickness vary as a function of SCZ PRS. Although this was not the case for most other brain measures assessed, our specific findings still provide some further evidence that MDD in the presence of high genetic risk for SCZ is subtly neurobiologically distinct from MDD in general.
The mechanisms underlying both depressive and anxiety disorders remain poorly understood. One of the reasons for this is the lack of a valid, evidence-based system to classify persons into specific subtypes based on their depressive and/or anxiety symptomatology. In order to do this without a priori assumptions, non-parametric statistical methods seem the optimal choice. Moreover, to define subtypes according to their symptom profiles and inter-relations between symptoms, network models may be very useful. This study aimed to evaluate the potential usefulness of this approach.
A large community sample from the Canadian general population (N = 254 443) was divided into data-driven clusters using non-parametric k-means clustering. Participants were clustered according to their (co)variation around the grand mean on each item of the Kessler Psychological Distress Scale (K10). Next, to evaluate cluster differences, semi-parametric network models were fitted in each cluster and node centrality indices and network density measures were compared.
A five-cluster model was obtained from the cluster analyses. Network density varied across clusters, and was highest for the cluster of people with the lowest K10 severity ratings. In three cluster networks, depressive symptoms (e.g. feeling depressed, restless, hopeless) had the highest centrality. In the remaining two clusters, symptom networks were characterised by a higher prominence of somatic symptoms (e.g. restlessness, nervousness).
Finding data-driven subtypes based on psychological distress using non-parametric methods can be a fruitful approach, yielding clusters of persons that differ in illness severity as well as in the structure and strengths of inter-symptom relationships.
The seasonality of individual influenza subtypes/lineages and the association of influenza epidemics with meteorological factors in the tropics/subtropics have not been well understood. The impact of the 2009 H1N1 pandemic on the prevalence of seasonal influenza virus remains to be explored. Using wavelet analysis, the periodicities of A/H3N2, seasonal A/H1N1, A/H1N1pdm09, Victoria and Yamagata were identified, respectively, in Panzhihua during 2006–2015. As a subtropical city in southwestern China, Panzhihua is the first industrial city in the upper reaches of the Yangtze River. The relationship between influenza epidemics and local climatic variables was examined based on regression models. The temporal distribution of influenza subtypes/lineages during the pre-pandemic (2006–2009), pandemic (2009) and post-pandemic (2010–2015) years was described and compared. A total of 6892 respiratory specimens were collected and 737 influenza viruses were isolated. A/H3N2 showed an annual cycle with a peak in summer–autumn, while A/H1N1pdm09, Victoria and Yamagata exhibited an annual cycle with a peak in winter–spring. Regression analyses demonstrated that relative humidity was positively associated with A/H3N2 activity while negatively associated with Victoria activity. Higher prevalence of A/H1N1pdm09 and Yamagata was driven by lower absolute humidity. The role of weather conditions in regulating influenza epidemics could be complicated since the diverse viral transmission modes and mechanism. Differences in seasonality and different associations with meteorological factors by influenza subtypes/lineages should be considered in epidemiological studies in the tropics/subtropics. The development of subtype- and lineage-specific prevention and control measures is of significant importance.
The aim of this meta-analysis was to provide a comprehensive overview of human immunodeficiency virus (HIV)-1 subtypes and to investigate temporal and geographical trends of the HIV-1 epidemic among men who have sex with men (MSM) in China. Chinese and English articles published between January 2007 and December 2017 were systematically searched. Pooled HIV-1 prevalence was calculated, and its stability was analysed using sensitivity analysis. Subgroups were based on study time period, sampling area and prevalence. Publication bias was measured using Funnel plot and Egger's test. A total of 68 independent studies that included HIV-1 molecular investigations were eligible for meta-analysis. Circulating recombinant form (CRF) 01_AE (57.36%, 95% confidence interval (CI) 53.76–60.92) was confirmed as the most prevalent HIV-1 subtype among MSM in China. Subgroup analysis for time period found that CRF01_AE steadily increased prior to 2012 but decreased during 2012–2016. Further whereas CRF07_BC increased over time, B/B′ decreased over time. CRF55_01B has increased in recent years, with higher pooled estimated rate in Guangdong (12.22%, 95% CI 10.34–13.17) and Fujian (8.65%, 95% CI 4.98–13.17) provinces. The distribution of HIV-1 subtypes among MSM in China has changed across different regions and periods. HIV-1 strains in MSM are becoming more complex. Long-term molecular monitoring in this population remains necessary for HIV-1 epidemic control and prevention.
Delirium is heterogeneous and can vary by etiology.
We sought to determine how delirium subtyped by etiology affected six-month function and cognition.
Prospective cohort study.
Tertiary care, academic medical center.
A total of 228 hospitalized patients > 65 years old were admitted from the emergency department (ED).
The modified Brief Confusion Assessment Method was used to determine delirium in the ED. Delirium etiology was determined by three trained physician reviewers using a Delirium Etiology checklist. Pre-illness and six-month function and cognition were determined using the Older American Resources and Services Activities of Daily Living (OARS ADL) questionnaire and the short-form Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Multiple linear regression was performed to determine if delirium etiology subtypes were associated with six-month function and cognition adjusted for baseline OARS ADL and IQCODE. Two-factor interactions were incorporated to determine pre-illness function or cognition-modified relationships between delirium subtypes and six-month function and cognition.
In patients with poorer pre-illness function only, delirium secondary to metabolic disturbance (β coefficient = −2.9 points, 95%CI: −0.3 to −5.6) and organ dysfunction (β coefficient = −4.3 points, 95%CI: −7.2 to −1.4) was significantly associated with poorer six-month function. In patients with intact cognition only, delirium secondary to central nervous system insults was significantly associated with poorer cognition (β coefficient = 0.69, 95%CI: 0.19 to 1.20).
Delirium is heterogeneous and different etiologies may have different prognostic implications. Furthermore, the effect of these delirium etiologies on outcome may be dependent on the patient's pre-illness functional status and cognition.
To date, genotyping data on giardiasis have not been available in the Czech Republic. In this study, we characterized 47 human isolates of Giardia intestinalis from symptomatic as well as asymptomatic giardiasis cases. Genomic DNA from trophozoites was tested by PCR-sequence analysis at three loci (β-giardin, glutamate dehydrogenase and triose phosphate isomerase). Sequence analysis showed assemblages A and B in 41 (87.2%) and six (12.8%) isolates, respectively. Two of the 41 assemblage A samples were genotyped as sub-assemblage AI, and 39 were genotyped as sub-assemblage AII. Four previously identified multilocus genotypes (MLGs: AI-1, AII-1, AII-4 and AII-9) and six likely novel variations of MLGs were found. In agreement with previous studies, sequences from assemblage B isolates were characterized by a large genetic variability and by the presence of heterogeneous positions, which prevent the definition of MLGs. This study also investigated whether there was a relationship between the assemblage and clinical data (including drug resistance). However, due to the large number of genotypes and the relatively small number of samples, no significant associations with the clinical data were found.
The evidence on a cancer-protective effect of the Mediterranean diet (MD) is still limited. Therefore, we investigated the association between MD adherence and lung cancer risk. Data were used from 120 852 participants of the Netherlands Cohort Study (NLCS), aged 55–69 years. Dietary habits were assessed at baseline (1986) using a validated FFQ and alternate and modified Mediterranean diet scores (aMED and mMED, respectively), including and excluding alcohol, were calculated. After 20·3 years of follow-up, 2861 lung cancer cases and 3720 subcohort members (case-cohort design) could be included in multivariable Cox regression analyses. High (6–8) v. low (0–3) aMED excluding alcohol was associated with non-significantly reduced lung cancer risks in men and women with hazard ratios of 0·91 (95 % CI 0·72, 1·15) and 0·73 (95 % CI 0·49, 1·09), respectively. aMED-containing models generally fitted better than mMED-containing models. In never smokers, a borderline significant decreasing trend in lung cancer risk was observed with increasing aMED excluding alcohol. Analyses stratified by the histological lung cancer subtypes did not identify subtypes with a particularly strong inverse relation with MD adherence. Generally, the performance of aMED and World Cancer Research Fund/American Institute for Cancer Research dietary score variants without alcohol was comparable. In conclusion, MD adherence was non-significantly inversely associated with lung cancer risk in the NLCS. Future studies should focus on differences in associations across the sexes and histological subtypes. Furthermore, exclusion of alcohol from MD scores should be investigated more extensively, primarily with respect to a potential role of the MD in cancer prevention.
Objectives: The aim of this study was to identify natural subgroups of older adults based on cognitive performance, and to establish each subgroup’s characteristics based on demographic factors, physical function, psychosocial well-being, and comorbidity. Methods: We applied latent class (LC) modeling to identify subgroups in baseline assessments of 1345 Einstein Aging Study (EAS) participants free of dementia. The EAS is a community-dwelling cohort study of 70+ year-old adults living in the Bronx, NY. We used 10 neurocognitive tests and 3 covariates (age, sex, education) to identify latent subgroups. We used goodness-of-fit statistics to identify the optimal class solution and assess model adequacy. We also validated our model using two-fold split-half cross-validation. Results: The sample had a mean age of 78.0 (SD=5.4) and a mean of 13.6 years of education (SD=3.5). A 9-class solution based on cognitive performance at baseline was the best-fitting model. We characterized the 9 identified classes as (i) disadvantaged, (ii) poor language, (iii) poor episodic memory and fluency, (iv) poor processing speed and executive function, (v) low average, (vi) high average, (vii) average, (viii) poor executive and poor working memory, (ix) elite. The cross validation indicated stable class assignment with the exception of the average and high average classes. Conclusions: LC modeling in a community sample of older adults revealed 9 cognitive subgroups. Assignment of subgroups was reliable and associated with external validators. Future work will test the predictive validity of these groups for outcomes such as Alzheimer’s disease, vascular dementia and death, as well as markers of biological pathways that contribute to cognitive decline. (JINS, 2018, 24, 511–523)
We aimed to determine whether individuals with obsessive-compulsive disorder (OCD) and demographically matched healthy individuals can be clustered into distinct clinical subtypes based on dimensional measures of their self-reported compulsivity (OBQ–44 and IUS–12) and impulsivity (UPPS–P).
Participants (n=217) were 103 patients with a clinical diagnosis of OCD; 79 individuals from the community who were “OCD-likely” according to self-report (Obsessive-Compulsive Inventory–Revised scores equal or greater than 21); and 35 healthy controls. All data were collected between 2013 and 2015 using self-report measures that assessed different aspects of compulsivity and impulsivity. Principal component analysis revealed two components broadly representing an individual's level of compulsivity and impulsivity. Unsupervised clustering grouped participants into four subgroups, each representing one part of an orthogonal compulsive-impulsive phenotype.
Clustering converged to yield four subgroups: one group low on both compulsivity and impulsivity, comprised mostly of healthy controls and demonstrating the lowest OCD symptom severity; two groups showing roughly equal clinical severity, but with opposing drivers (i.e., high compulsivity and low impulsivity, and vice versa); and a final group high on both compulsivity and impulsivity and recording the highest clinical severity. Notably, the largest cluster of individuals with OCD was characterized by high impulsivity and low compulsivity. Our results suggest that both impulsivity and compulsivity mediate obsessive-compulsive symptomatology.
Individuals with OCD can be clustered into distinct subtypes based on measures of compulsivity and impulsivity, with the latter being found to be one of the more defining characteristics of the disorder. These dimensions may serve as viable and novel treatment targets.
Since its inception, relational aggression has been conceptualised as a set of destructive attempts by young girls to get their own way, and these aggressive acts have been demonised in public and media debate. This article challenges the prevailing developmental psychopathologisation literature to centre the focus on functionality, positioning relational aggression as a set of behaviours that are used as specific communication strategies. A ‘Girls’ Relational Aggression Communication Model’ is provided as a new conceptual framework that integrates positioning subtypes from the literature: ‘popular’, ‘regular’, and ‘tough’ girls. This reconceptualised communication model is a contribution to the field as it enhances understanding of the nuances in girls’ relationships. In particular, it reframes the positioning of ‘tough’ girls, who have been largely ignored in relational aggression research.
The management of and prognosis for delirium are affected by its subtype: hypoactive, hyperactive, mixed, and none. The DMSS–4, an abbreviated version of the Delirium Motor Symptom Scale, is a brief instrument for the assessment of delirium subtypes. However, it has not yet been evaluated in an intensive care setting.
We performed a prospective/descriptive cohort study in order to determine the internal consistency, reliability, and validity of the relevant items of the DMSS–4 versus the Delirium Rating Scale–Revised-98 (DRS–R-98) and the original DMSS in a surgical intensive care setting.
A total of 289 elderly, predominantly male patients were screened for delirium, and 122 were included in our sample. The internal consistency of the DMSS–4 items was excellent (Cronbach's α = 0.92), and between the DMSS–4 and DRS–R-98 the overall concurrent validity was substantial (Cramer's V = 0.67). Within individual motor subtypes, concurrent validity remained at least substantial (Cohen's κ = 0.65–0.81) and sensitivity high (69.8 to 82.2%), in contrast to those of the no-motor subtype, with less validity and sensitivity (κ = 0.28, 22%). Similarly, total concurrent validity between the DMSS–4 and the original DMSS reached perfection (Cramer's V = 0.83), as did agreement between the subtypes (κ = 0.83–0.92), while sensitivity remained high (88.2–100%). Only in those with delirium with no-motor subtype was agreement moderate (κ = 0.56) and sensitivity lower (67%). Specificity was high across all subtypes (91.2–99.1%). The DMSS–4 yielded very sensitive ratings, particularly for hypoactive and hyperactive motor symptoms, and interrater agreement was excellent (Fleiss's κ = 0.83).
Significance of Results:
We found the DMSS–4 to be a most reliable and valid brief assessment of delirium in characterizing the subtypes of delirium in an intensive care setting, with increased sensitivity to hypoactive and hyperactive motor alterations.
Blastocystis sp. is a protozoan commonly found in human and animal stool samples. Several pathogenic and zoonotic aspects of this organism are still unknown. The aim of the present study was to investigate Blastocystis subtypes (STs) in samples from patients of the Hospital das Clínicas of the Faculdade de Medicina at the Universidade de São Paulo (HC-FMUSP), Brazil. Blastocystis sp.-positive stool samples diagnosed at the Section of Parasitology of the Central Laboratory (HC-FMUSP) were used for DNA isolation. Polymerase chain reaction (PCR) was performed using specific primers targeting the small-subunit rRNA gene. Direct DNA sequencing of the PCR products was performed and the DNA sequences were then aligned and compared with other sequences obtained from the GenBank database. Phylogenetic analysis was used to identify STs and determine the phylogenetic relationships between the sequences. Four STs were identified: ST1 (22·5%), ST2 (12·5%), ST3 (60%) and ST6 (5%). In conclusion, ST3 was the most prevalent ST among the human isolates followed by ST1. The present study is one of the few providing STs data from the human population in South America. Determining ST prevalence in human samples may contribute to the monitoring of Blastocystis sp. infection transmission in endemic regions.
In search of empirical classifications of depression and anxiety, most subtyping studies focus solely on symptoms and do so within a single disorder. This study aimed to identify and validate cross-diagnostic subtypes by simultaneously considering symptoms of depression and anxiety, and disability measures.
A large cohort of adults (Lifelines, n = 73 403) had a full assessment of 16 symptoms of mood and anxiety disorders, and measurement of physical, social and occupational disability. The best-fitting subtyping model was identified by comparing different hybrid mixture models with and without disability covariates on fit criteria in an independent test sample. The best model's classes were compared across a range of external variables.
The best-fitting Mixed Measurement Item Response Theory model with disability covariates identified five classes. Accounting for disability improved differentiation between people reporting isolated non-specific symptoms [‘Somatic’ (13.0%), and ‘Worried’ (14.0%)] and psychopathological symptoms [‘Subclinical’ (8.8%), and ‘Clinical’ (3.3%)]. Classes showed distinct associations with clinically relevant external variables [e.g. somatization: odds ratio (OR) 8.1–12.3, and chronic stress: OR 3.7–4.4]. The Subclinical class reported symptomatology at subthreshold levels while experiencing disability. No pure depression or anxiety, but only mixed classes were found.
An empirical classification model, incorporating both symptoms and disability identified clearly distinct cross-diagnostic subtypes, indicating that diagnostic nets should be cast wider than current phenomenology-based categorical systems.
Delirium is a common neuropsychiatric syndrome with considerable heterogeneity in clinical profile. Rapid reliable identification of clinical subtypes can allow for more targeted research efforts.
We explored the concordance in attribution of motor subtypes between the Delirium Motor Subtyping Scale 4 (DMSS-4) and the original Delirium Motor Subtyping Scale (DMSS) (assessed cross-sectionally) and subtypes defined longitudinally using the Delirium Symptom Interview (DSI).
We included 113 elderly patients developing DSM-IV delirium after hip-surgery [mean age 86.9 ± 6.6 years; range 65–102; 68.1% females; 25 (22.1%) had no previous history of cognitive impairment]. Concordance for the first measurement was high for both the DMSS-4 and original DMSS (k = 0.82), and overall for the DMSS-4 and DSI (k = 0.84). The DMSS-4 also demonstrated high internal consistency (McDonald's omega = 0.90). The DSI more often allocated an assessment to “no subtype” compared to the DMSS-4 and DMSS-11, which showed higher inclusion rates for motor subtypes.
The DMSS-4 provides a rapid method of identifying motor-defined clinical subtypes of delirium and appears to be a reliable alternative to the more detailed and time-consuming original DMSS and DSI methods of subtype attribution. The DMSS-4, so far translated into three languages, can be readily applied to further studies of causation, treatment and outcome in delirium.
Neurofeedback is a neuronal self-regulation technique that teaches people to modulate their brain frequencies using visual and auditory reinforcements presented on a computer screen. To assess the effect of neurofeedback training in children with ADHD as far as improved attention and impulse control, and analyze whether or not there are differences between the inattentive and hyperactive subtypes. Fifty children diagnosed with ADHD participated in the study: 14 comprised the control group, and 36 the experimental group (16 with the inattentive ADHD subtype, 20 with the hyperactive ADHD subtype). Attention and impulse control were assessed using the Integrated Visual Auditory CPT (IVA/CPT). Results indicated that the predominantly inattentive group showed significant differences on the Control Scale (p = .023, d = 1.31) and the Attention Scale (p < .01, d = 1.89) of the IVA/CPT; meanwhile the predominantly hyperactive group showed significant improvement on the Control Scale (p = .016, d = 1.21). The control group exhibited no significant differences on either of the two scales (p > .5). In terms of theta/beta ratio, no significant differences were detected (p = .10) between ADHD subtypes. The findings suggest that neurofeedback training using the theta/beta protocol was more effective in the predominantly inattentive subset of individuals with ADHD.
Delirium is a common neuropsychiatric syndrome that includes clinical subtypes identified by the Delirium Motor Subtyping Scale (DMSS). We explored the concordance between the DMSS and an abbreviated 4-item version in elderly medical inpatients.
Elderly general medical admissions (n = 145) were assessed for delirium using the Revised Delirium Rating scale (DRS-R98). Clinical subtype was assessed with the DMSS (which includes the four items included in the DMSS-4). Motor subtypes were generated for all patient assessments using both versions of the scale. The concordance of the original and abbreviated DMSS was examined.
The agreement between the DMSS and DMSS-4 was high, both at initial and subsequent assessments (κ range 0.75–0.91). Intraclass Correlation Coefficient (ICC) for all three raters for the DMSS was high (0.70) and for DMSS-4 was moderate (0.59). Analysis of the agreement between raters for individual DMSS items found higher concordance in respect of hypoactive features compared to hyperactive.
The DMSS-4 allows for rapid assessment of clinical subtype in delirium and has high concordance with the longer and well-validated DMSS, including over longitudinal assessment. There is good inter-rater reliability between medical and nursing staff. More consistent clinical subtyping can facilitate better delirium management and more focused research effort.
Depression and anxiety in Parkinson's disease are common and frequently co-morbid, with significant impact on health outcome. Nevertheless, management is complex and often suboptimal. The existence of clinical subtypes would support stratified approaches in both research and treatment.
Five hundred and thirteen patients with Parkinson's disease were assessed annually for up to 4 years. Latent transition analysis (LTA) was used to identify classes that may conform to clinically meaningful subgroups, transitions between those classes over time, and baseline clinical and demographic features that predict common trajectories.
In total, 64.1% of the sample remained in the study at year 4. LTA identified four classes, a ‘Psychologically healthy’ class (approximately 50%), and three classes associated with psychological distress: one with moderate anxiety alone (approximately 20%), and two with moderate levels of depression plus moderate or severe anxiety. Class membership tended to be stable across years, with only about 15% of individuals transitioning between the healthy class and one of the distress classes. Stable distress was predicted by higher baseline depression and psychiatric history and younger age of onset of Parkinson's disease. Those with younger age of onset were also more likely to become distressed over the course of the study.
Psychopathology was characterized by relatively stable anxiety or anxious-depression over the 4-year period. Anxiety, with or without depression, appears to be the prominent psychopathological phenotype in Parkinson's disease suggesting a pressing need to understanding its mechanisms and improve management.