Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 170
Filtrar
1.
Cereb Cortex ; 32(4): 755-769, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34416764

RESUMO

Microgravity alters vestibular signaling. In-flight adaptation to altered vestibular afferents is reflected in post-spaceflight aftereffects, evidenced by declines in vestibularly mediated behaviors (e.g., walking/standing balance), until readaptation to Earth's 1G environment occurs. Here we examine how spaceflight affects neural processing of applied vestibular stimulation. We used fMRI to measure brain activity in response to vestibular stimulation in 15 astronauts pre- and post-spaceflight. We also measured vestibularly-mediated behaviors, including balance, mobility, and rod-and-frame test performance. Data were collected twice preflight and four times postflight. As expected, vestibular stimulation at the preflight sessions elicited activation of the parietal opercular area ("vestibular cortex") and deactivation of somatosensory and visual cortices. Pre- to postflight, we found widespread reductions in this somatosensory and visual cortical deactivation, supporting sensory compensation and reweighting with spaceflight. These pre- to postflight changes in brain activity correlated with changes in eyes closed standing balance, and greater pre- to postflight reductions in deactivation of the visual cortices associated with less postflight balance decline. The observed brain changes recovered to baseline values by 3 months postflight. Together, these findings provide evidence for sensory reweighting and adaptive cortical neuroplasticity with spaceflight. These results have implications for better understanding compensation and adaptation to vestibular functional disruption.


Assuntos
Voo Espacial , Vestíbulo do Labirinto , Astronautas , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Humanos , Equilíbrio Postural/fisiologia
2.
Diabet Med ; 37(8): 1367-1373, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31557346

RESUMO

AIM: To determine the patterns and predictors of pharmacological treatment initiation for type 2 diabetes and whether treatment initiation is consistent with Australian clinical practice guidelines that recommend metformin monotherapy. METHODS: Individuals aged 40-99 years initiating a non-insulin type 2 diabetes medication between July 2013 and February 2018 were identified from a 10% random national sample of pharmacy dispensing data. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the predictors of initiating sulfonylurea monotherapy, non-guideline monotherapy and combination therapy compared with metformin monotherapy. Predictors included age, sex, initiation year and comorbidities determined using the Rx-Risk comorbidity index. RESULTS: Of the 47 860 initiators, [47% women, mean age 60.7 (sd 12.1) years], 85.8%, 4.6%, 1.9% and 7.7% received metformin monotherapy, sulfonylurea monotherapy, non-guideline monotherapy and combination therapy, respectively. Increasing age was associated with increasing odds of initiating sulfonylurea monotherapy and non-guideline monotherapy. Combination therapy initiation was less likely in women (OR 0.74, 95% CI 0.69-0.79) and people with more comorbidities (e.g. OR 0.36, 95% CI 0.29-0.44 for seven or more comorbidities vs. no comorbidities) but more likely in congestive heart failure (OR 1.42, 95% CI 1.22-1.65), cerebrovascular disease (OR 1.50, 95% CI 1.32-1.69) and dyslipidaemia (OR 1.29, 95% CI 1.19-1.40). CONCLUSION: Treatment initiation in Australia is largely consistent with clinical practice guidelines, with 86% of individuals initiating metformin monotherapy. Initiation on combination therapy was more common in men and in those with fewer comorbidities.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Fidelidade a Diretrizes/estatística & dados numéricos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Guias de Prática Clínica como Assunto , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Transtornos Cerebrovasculares/epidemiologia , Comorbidade , Diabetes Mellitus Tipo 2/epidemiologia , Quimioterapia Combinada , Dislipidemias/epidemiologia , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Compostos de Sulfonilureia/uso terapêutico
3.
Psychol Med ; 48(1): 132-141, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28625185

RESUMO

BACKGROUND: Cognitive deficits are a core feature of schizophrenia, and impairments in most domains are thought to be stable over the course of the illness. However, cross-sectional evidence indicates that some areas of cognition, such as visuospatial associative memory, may be preserved in the early stages of psychosis, but become impaired in later established illness stages. This longitudinal study investigated change in visuospatial and verbal associative memory following psychosis onset. METHODS: In total 95 first-episode psychosis (FEP) patients and 63 healthy controls (HC) were assessed on neuropsychological tests at baseline, with 38 FEP and 22 HCs returning for follow-up assessment at 5-11 years. Visuospatial associative memory was assessed using the Cambridge Neuropsychological Test Automated Battery Visuospatial Paired-Associate Learning task, and verbal associative memory was assessed using Verbal Paired Associates subtest of the Wechsler Memory Scale - Revised. RESULTS: Visuospatial and verbal associative memory at baseline did not differ significantly between FEP patients and HCs. However, over follow-up, visuospatial associative memory deteriorated significantly for the FEP group, relative to healthy individuals. Conversely, verbal associative memory improved to a similar degree observed in HCs. In the FEP cohort, visuospatial (but not verbal) associative memory ability at baseline was associated with functional outcome at follow-up. CONCLUSIONS: Areas of cognition that develop prior to psychosis onset, such as visuospatial and verbal associative memory, may be preserved early in the illness. Later deterioration in visuospatial memory ability may relate to progressive structural and functional brain abnormalities that occurs following psychosis onset.


Assuntos
Cognição , Transtornos Psicóticos/psicologia , Esquizofrenia/fisiopatologia , Memória Espacial , Adolescente , Adulto , Austrália , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Análise de Regressão , Percepção Visual , Adulto Jovem
4.
Mol Psychiatry ; 22(3): 396-406, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27400857

RESUMO

Lithium is a first-line therapy for bipolar affective disorder. However, various adverse effects, including a Parkinson-like hand tremor, often limit its use. The understanding of the neurobiological basis of these side effects is still very limited. Nigral iron elevation is also a feature of Parkinsonian degeneration that may be related to soluble tau reduction. We found that magnetic resonance imaging T2 relaxation time changes in subjects commenced on lithium therapy were consistent with iron elevation. In mice, lithium treatment lowers brain tau levels and increases nigral and cortical iron elevation that is closely associated with neurodegeneration, cognitive loss and parkinsonian features. In neuronal cultures lithium attenuates iron efflux by lowering tau protein that traffics amyloid precursor protein to facilitate iron efflux. Thus, tau- and amyloid protein precursor-knockout mice were protected against lithium-induced iron elevation and neurotoxicity. These findings challenge the appropriateness of lithium as a potential treatment for disorders where brain iron is elevated (for example, Alzheimer's disease), and may explain lithium-associated motor symptoms in susceptible patients.


Assuntos
Lítio/efeitos adversos , Lítio/metabolismo , Proteínas tau/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Humanos , Ferro/metabolismo , Masculino , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Transtornos Parkinsonianos/metabolismo , Proteínas tau/antagonistas & inibidores
5.
Psychol Med ; 47(4): 616-626, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27821204

RESUMO

BACKGROUND: Cannabis use shows a robust dose-dependent relationship with psychosis risk among the general population. Despite this, it has been difficult to link cannabis use with risk for transitioning to a psychotic disorder among individuals at ultra-high risk (UHR) for psychosis. The present study examined UHR transition risk as a function of cannabis use characteristics which vary substantially between individuals including age of first use, cannabis abuse severity and a history of cannabis-induced attenuated psychotic symptoms (APS). METHOD: Participants were 190 UHR individuals (76 males) recruited at entry to treatment between 2000 and 2006. They completed a comprehensive baseline assessment including a survey of cannabis use characteristics during the period of heaviest use. Outcome was transition to a psychotic disorder, with mean time to follow-up of 5.0 years (range 2.4-8.7 years). RESULTS: A history of cannabis abuse was reported in 58% of the sample. Of these, 26% reported a history of cannabis-induced APS. These individuals were 4.90 (95% confidence interval 1.93-12.44) times more likely to transition to a psychotic disorder (p = 0.001). Greater severity of cannabis abuse also predicted transition to psychosis (p = 0.036). However, this effect was mediated by higher abuse severity among individuals with a history of cannabis-induced APS. CONCLUSIONS: Findings suggest that cannabis use poses risk in a subpopulation of UHR individuals who manifest cannabis-induced APS. Whether this reflects underlying genetic vulnerability requires further study. Nevertheless, findings reveal an important early marker of risk with potentially significant prognostic utility for UHR individuals.


Assuntos
Cannabis/efeitos adversos , Progressão da Doença , Abuso de Maconha/complicações , Psicoses Induzidas por Substâncias/etiologia , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Risco , Adulto Jovem
6.
Psychol Med ; 46(13): 2771-83, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27396386

RESUMO

BACKGROUND: Salience network (SN) dysconnectivity has been hypothesized to contribute to schizophrenia. Nevertheless, little is known about the functional and structural dysconnectivity of SN in subjects at risk for psychosis. We hypothesized that SN functional and structural connectivity would be disrupted in subjects with At-Risk Mental State (ARMS) and would be associated with symptom severity and disease progression. METHOD: We examined 87 ARMS and 37 healthy participants using both resting-state functional magnetic resonance imaging and diffusion tensor imaging. Group differences in SN functional and structural connectivity were examined using a seed-based approach and tract-based spatial statistics. Subject-level functional connectivity measures and diffusion indices of disrupted regions were correlated with CAARMS scores and compared between ARMS with and without transition to psychosis. RESULTS: ARMS subjects exhibited reduced functional connectivity between the left ventral anterior insula and other SN regions. Reduced fractional anisotropy (FA) and axial diffusivity were also found along white-matter tracts in close proximity to regions of disrupted functional connectivity, including frontal-striatal-thalamic circuits and the cingulum. FA measures extracted from these disrupted white-matter regions correlated with individual symptom severity in the ARMS group. Furthermore, functional connectivity between the bilateral insula and FA at the forceps minor were further reduced in subjects who transitioned to psychosis after 2 years. CONCLUSIONS: Our findings support the insular dysconnectivity of the proximal SN hypothesis in the early stages of psychosis. Further developed, the combined structural and functional SN assays may inform the prognosis of persons at-risk for psychosis.


Assuntos
Córtex Cerebral , Imageamento por Ressonância Magnética/métodos , Transtornos Psicóticos , Substância Branca , Adolescente , Adulto , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/patologia , Transtornos Psicóticos/fisiopatologia , Risco , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Substância Branca/fisiopatologia , Adulto Jovem
7.
Acta Psychiatr Scand ; 133(5): 352-67, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26661730

RESUMO

OBJECTIVE: Auditory verbal hallucinations (AVHs) are core features of psychotic illness and remain significant in predicting poor outcome and risk. There has been a wide range of approaches to understanding these experiences. METHOD: A systematic literature review summarizing different methods of investigation and their results; phenomenology, descriptive psychopathology, psychological, cognitive neurobiology, and neuroimaging. RESULTS: A number of 764 papers and texts were screened and 113 reviewed. Phenomenological studies are comparably few in number, and psychopathology remains based on concepts defined in the early 20th century. Psychological models focus on voice content and emotional reaction, and suggest a continuum of AVHs from normal experience. Neuropsychological models include AVHs as misattribution of inner speech, whilst functional neuroimaging studies focus on the spontaneous activity and connectivity of auditory networks. CONCLUSION: There has been a large growth in research on AVHs in recent decades dominated by neurobiological and neuroimaging studies. Future research should include focus on phenomenological aspects and AVHs change over the course of developing illness. Integration between branches of enquiry is needed, and the risk is that without this, models are proposed and investigated that bear scant relevance to the symptom itself.


Assuntos
Encéfalo/fisiopatologia , Alucinações/fisiopatologia , Percepção da Fala/fisiologia , Humanos
8.
Cogn Neuropsychiatry ; 21(5): 402-411, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27438900

RESUMO

INTRODUCTION: Patients with schizophrenia show impairments in working-memory and visual-spatial processing, but little is known about the dynamic interplay between the two. To provide insight into this important question, we examined the effect of positive and negative symptom expressions in healthy adults on perceptual processing while concurrently performing a working-memory task that requires the allocations of various degrees of cognitive resources. METHODS: The effect of positive and negative symptom expressions in healthy adults (N = 91) on perceptual processing was examined in a dual-task paradigm of visual-spatial working memory (VSWM) under three conditions of cognitive load: a baseline condition (with no concurrent working-memory demand), a low VSWM load condition, and a high VSWM load condition. RESULTS: Participants overall performed more efficiently (i.e., faster) with increasing cognitive load. This facilitation in performance was unrelated to symptom expressions. However, participants with high-negative, low-positive symptom expressions were less accurate in the low VSWM condition compared to the baseline and the high VSWM load conditions. CONCLUSIONS: Attenuated, subclinical expressions of psychosis affect cognitive performance that is impaired in schizophrenia. The "resource limitations hypothesis" may explain the performance of the participants with high-negative symptom expressions. The dual-task of visual-spatial processing and working memory may be beneficial to assessing the cognitive phenotype of individuals with high risk for schizophrenia spectrum disorders.


Assuntos
Memória de Curto Prazo/fisiologia , Pessimismo/psicologia , Estimulação Luminosa/métodos , Transtornos Psicóticos/psicologia , Processamento Espacial/fisiologia , Adolescente , Estudos de Coortes , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Distribuição Aleatória , Tempo de Reação/fisiologia , Esquizofrenia , Adulto Jovem
9.
Psychol Med ; 45(16): 3453-65, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26166153

RESUMO

BACKGROUND: Individuals identified as at ultra-high risk (UHR) for psychosis are at risk of poor functional outcome regardless of development of psychotic disorder. Studies examining longitudinal predictors of poor functioning have tended to be small and report only medium-term follow-up data. We sought to examine clinical predictors of functional outcome in a long-term longitudinal study. METHOD: Participants were 268 (152 females, 116 males) individuals identified as UHR 2-14 years previously. A range of clinical and sociodemographic variables were assessed at baseline. Functioning at follow-up was assessed using the Social and Occupational Functioning Assessment Scale (SOFAS). RESULTS: Baseline negative symptoms, impaired emotional functioning, disorders of thought content, low functioning, past substance use disorder and history of childhood maltreatment predicted poor functioning at follow-up in univariate analyses. Only childhood maltreatment remained significant in the multivariate analysis (p < 0.001). Transition to psychosis was also significantly associated with poor functioning at long-term follow-up [mean SOFAS score 59.12 (s.d. = 18.54) in the transitioned group compared to 70.89 (s.d. = 14.00) in the non-transitioned group, p < 0.001]. Childhood maltreatment was a significant predictor of poor functioning in both the transitioned and non-transitioned groups. CONCLUSIONS: Childhood maltreatment and transition to psychotic disorder independently predicted poor long-term functioning. This suggests that it is important to assess history of childhood maltreatment in clinical management of UHR individuals. The finding that transition to psychosis predicts poor long-term functioning strengthens the evidence that the UHR criteria detect a subgroup at risk for schizophrenia.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância/psicologia , Ansiedade/diagnóstico , Depressão/diagnóstico , Esquizofrenia/diagnóstico , Adolescente , Adulto , Cognição , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Análise Multivariada , Testes Neuropsicológicos , Prognóstico , Escalas de Graduação Psiquiátrica , Medição de Risco , Adulto Jovem
10.
Psychol Med ; 45(3): 515-27, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25077698

RESUMO

BACKGROUND: Whether there are differential effects of first-generation antipsychotics (FGAs) and second-generation antipsychotics (SGAs) on the brain is currently debated. Although some studies report that FGAs reduce grey matter more than SGAs, others do not, and research to date is limited by a focus on schizophrenia spectrum disorders. To address this limitation, this study investigated the effects of medication in patients being treated for first-episode schizophrenia or affective psychoses. METHOD: Cortical thickness was compared between 52 first-episode psychosis patients separated into diagnostic (i.e. schizophrenia or affective psychosis) and medication (i.e. FGA and SGA) subgroups. Patients in each group were also compared to age- and sex-matched healthy controls (n = 28). A whole-brain cortical thickness interaction analysis of medication and diagnosis was then performed. Correlations between cortical thickness with antipsychotic dose and psychotic symptoms were examined. RESULTS: The effects of medication and diagnosis did not interact, suggesting independent effects. Compared with controls, diagnostic differences were found in frontal, parietal and temporal regions. Decreased thickness in FGA-treated versus SGA-treated groups was found in a large frontoparietal region (p < 0.001, corrected). Comparisons with healthy controls revealed decreased cortical thickness in the FGA group whereas the SGA group showed increases in addition to decreases. In FGA-treated patients cortical thinning was associated with higher negative symptoms whereas increased cortical thickness in the SGA-treated group was associated with lower positive symptoms. CONCLUSIONS: Our results suggest that FGA and SGA treatments have divergent effects on cortical thickness during the first episode of psychosis that are independent from changes due to illness.


Assuntos
Transtornos Psicóticos Afetivos/tratamento farmacológico , Antipsicóticos/classificação , Antipsicóticos/uso terapêutico , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
11.
Psychol Med ; 44(7): 1533-44, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23981686

RESUMO

BACKGROUND: Preterm birth confers risk for poor outcome, including mental health problems. Survival of extremely preterm (EP; <28 weeks' gestation) or extremely low birthweight (ELBW; <1000 g) infants increased in the 1990s but psychiatric outcomes in older adolescents born preterm since 1990 are not well documented. This study aimed to characterize mental health and personality traits in a prospective geographical cohort of adolescents born EP/ELBW in Victoria, Australia in 1991 and 1992. METHOD: At age 18 years, 215 EP/ELBW and 157 normal birthweight (>2499 g) control adolescents completed the Structured Clinical Interview for DSM-IV Disorders, Axis 1 Non-Patient version (SCID-I/NP), the Children's Interview for Psychiatric Syndromes (ChIPS) attention deficit hyperactivity disorder (ADHD) module, and questionnaires assessing recent depression and anxiety symptoms and personality traits. RESULTS: ADHD prevalence was significantly elevated in EP/ELBW adolescents compared with controls [15% v. 7%; odds ratio (OR) 2.67, 95% confidence interval (CI) 1.08-6.58]. Aside from ADHD, however, EP/ELBW and control adolescents reported very similar outcomes, with other lifetime diagnoses identified in 23% of EP/ELBW and 21% of controls. These were predominantly mood and anxiety disorders (21% EP/ELBW, 20% controls). The groups did not differ in recent depression or anxiety symptoms assessed using questionnaires, and personality traits were also similar. CONCLUSIONS: ADHD was more prevalent in EP/ELBW adolescents than controls, which is consistent with some, but not all, reports on preterm survivors born before the 1990s, and younger preterm children born in the 1990s. The high rates of anxiety and mood disorders were similar in both groups, and comparable with population-based estimates.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Peso ao Nascer , Idade Gestacional , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Lactente Extremamente Prematuro , Adolescente , Transtornos de Ansiedade/epidemiologia , Feminino , Humanos , Masculino , Transtornos do Humor/epidemiologia , Vitória/epidemiologia
12.
Psychol Med ; 44(3): 489-98, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23659473

RESUMO

BACKGROUND: Grey matter volume and cortical thickness represent two complementary aspects of brain structure. Several studies have described reductions in grey matter volume in people at ultra-high risk (UHR) of psychosis; however, little is known about cortical thickness in this group. The aim of the present study was to investigate cortical thickness alterations in UHR subjects and compare individuals who subsequently did and did not develop psychosis. METHOD: We examined magnetic resonance imaging data collected at four different scanning sites. The UHR subjects were followed up for at least 2 years. Subsequent to scanning, 50 UHR subjects developed psychosis and 117 did not. Cortical thickness was examined in regions previously identified as sites of neuroanatomical alterations in UHR subjects, using voxel-based cortical thickness. RESULTS: At baseline UHR subjects, compared with controls, showed reduced cortical thickness in the right parahippocampal gyrus (p < 0.05, familywise error corrected). There were no significant differences in cortical thickness between the UHR subjects who later developed psychosis and those who did not. CONCLUSIONS: These data suggest that UHR symptomatology is characterized by alterations in the thickness of the medial temporal cortex. We did not find evidence that the later progression to psychosis was linked to additional alterations in cortical thickness, although we cannot exclude the possibility that the study lacked sufficient power to detect such differences.


Assuntos
Giro Para-Hipocampal/patologia , Transtornos Psicóticos/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Interpretação Estatística de Dados , Progressão da Doença , Suscetibilidade a Doenças/patologia , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Tamanho do Órgão/fisiologia , Sintomas Prodrômicos , Medição de Risco , Adulto Jovem
13.
Acta Psychiatr Scand ; 130(1): 1-15, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24611632

RESUMO

OBJECTIVE: It is likely that cognitive deficits are vulnerability markers for developing schizophrenia, as these deficits are already well-established findings in first-episode psychosis. Studies at-risk adolescents and young adults are likely to provide information about cognitive deficits that predate the onset of the illness. METHOD: We conducted meta-analyses of studies comparing familial-high risk (FHR) or ultra-high risk (UHR; n = 2113) and healthy controls (n = 1748) in youth studies in which the mean age was between 15 and 29. RESULTS: Compared with controls, high risk subjects were impaired in each domain in both UHR (d = 0.34-0.71) and FHR (d = 0.24-0.81). Heterogeneity of effect sizes across studies was modest, increasing confidence to the findings of the current meta-analysis (I(2) = 0-0.18%). In both risk paradigms, co-occurrence of genetic risk with attenuated symptoms was associated with more severe cognitive dysfunction. In UHR, later transition to psychosis was associated with more severe cognitive deficits in all domains (d = 0.31-0.49) except sustained attention. However, cognitive impairment has a limited capacity to predict the outcome of high-risk patients. CONCLUSION: Cognitive deficits are already evident in adolescents and young adults who have familial or clinical risk for psychosis. Longitudinal developmental studies are important to reveal timing and trajectory of emergence of such deficits.


Assuntos
Transtornos Cognitivos/complicações , Transtornos Psicóticos/complicações , Adolescente , Adulto , Humanos , Testes Neuropsicológicos , Transtornos Psicóticos/genética , Fatores de Risco , Adulto Jovem
14.
NPJ Microgravity ; 10(1): 27, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472244

RESUMO

Microgravity alters vestibular signaling and reduces body loading, driving sensory reweighting. The unloading effects can be modelled using head-down tilt bedrest (HDT). Artificial gravity (AG) has been hypothesized to serve as an integrated countermeasure for the declines associated with HDT and spaceflight. Here, we examined the efficacy of 30 min of daily AG to counteract brain and behavior changes from 60 days of HDT. Two groups received 30 min of AG delivered via short-arm centrifuge daily (n = 8 per condition), either in one continuous bout, or in 6 bouts of 5 min. To improve statistical power, we combined these groups (AG; n = 16). Another group served as controls in HDT with no AG (CTRL; n = 8). We examined how HDT and AG affect vestibular processing by collecting fMRI scans during vestibular stimulation. We collected these data prior to, during, and post-HDT. We assessed brain activation initially in 12 regions of interest (ROIs) and then conducted an exploratory whole brain analysis. The AG group showed no changes in activation during vestibular stimulation in a cerebellar ROI, whereas the CTRL group showed decreased activation specific to HDT. Those that received AG and showed little pre- to post-HDT changes in left vestibular cortex activation had better post-HDT balance performance. Whole brain analyses identified increased pre- to during-HDT activation in CTRLs in the right precentral gyrus and right inferior frontal gyrus, whereas AG maintained pre-HDT activation levels. These results indicate that AG could mitigate activation changes in vestibular processing that is associated with better balance performance.

15.
Psychol Med ; 43(11): 2349-60, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23388122

RESUMO

BACKGROUND: Individuals at ultra-high risk (UHR) for psychosis show reduced neurocognitive performance across domains but it is unclear which reductions are associated with transition to frank psychosis. The aim of this study was to investigate differences in baseline neurocognitive performance between UHR participants with (UHR-P) and without transition to psychosis (UHR-NP) and a healthy control (HC) group and examine neurocognitive predictors of transition over the medium to long term. METHOD: A sample of 325 UHR participants recruited consecutively from the Personal Assessment and Crisis Evaluation (PACE) Clinic in Melbourne and 66 HCs completed a neurocognitive assessment at baseline. The UHR group was followed up between 2.39 and 14.86 (median = 6.45) years later. Cox regression was used to investigate candidate neurocognitive predictors of psychosis onset. RESULTS: The UHR group performed more poorly than the HC group across a range of neurocognitive domains but only performance on digit symbol coding and picture completion differed between the groups. The risk of transition was only significantly associated with poorer performance on visual reproduction [hazard ratio (HR) 0.919, 95% confidence interval (CI) 0.876-0.965, p = 0.001] and matrix reasoning (HR 0.938, 95% CI 0.883-0.996, p = 0.037). These remained significant even after controlling for psychopathology at baseline. CONCLUSIONS: This study is the longest follow-up of an UHR sample to date. UHR status was associated with poorer neurocognitive performance compared to HCs on some tasks. Cognition at identification as UHR was not a strong predictor of risk for transition to psychosis. The results suggests the need to include more experimental paradigms that isolate discrete cognitive processes to better understand neurocognition at this early stage of illness.


Assuntos
Transtornos Cognitivos/psicologia , Sintomas Prodrômicos , Transtornos Psicóticos/psicologia , Adolescente , Adulto , Estudos de Casos e Controles , Transtornos Cognitivos/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Modelos de Riscos Proporcionais , Transtornos Psicóticos/epidemiologia , Risco , Fatores de Risco , Adulto Jovem
16.
World J Surg ; 37(7): 1714-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23539194

RESUMO

BACKGROUND: In children with short bowel syndrome, maximal adaptation of the bowel after extensive resection is thought to occur during the first 2 years of life. The aim of the present study was to review children with short bowel syndrome from two intestinal rehabilitation centers, comparing those undergoing lengthening procedures <365 days of age (early) versus those whose lengthening procedure was carried out >365 days of age (late). METHODS: Retrospective data collection was performed from January 2004 to December 2010 in Manchester, UK, and from December 2006 to December 2010 in Brussels, Belgium. Both medical centers follow a similar intestinal rehabilitation program (IRP). Data collected included population demographics, bowel length preoperatively and postoperatively, age at operation, parenteral nutrition (PN), central access, and complications. RESULTS: Complete data were available for eight children who underwent lengthening surgery at <365 days of age, and six who underwent the procedure at >365 days of age. Diagnoses were similar. Groups were matched for gestation and birthweight, with no statistical difference in preoperative and postoperative bowel lengths. The mean duration of PN postoperatively was 378 days in the early cohort and 589 days in the late cohort. This trended toward statistical significance (p = 0.071). Full enteral autonomy was achieved at 17 months (early) and 59 months (late) (p = 0.01). Patients in the early group required fewer central lines than those operated on later (p = 0.035). CONCLUSIONS: Enrolling children into an IRP involving early (<365 days of age) lengthening surgery allows a shorter postoperative time to allow weaning to full enteral nutrition, as well as fewer central lines. Both outcomes provide benefits for the child and family, allowing an earlier return to normal life.


Assuntos
Intestino Delgado/cirurgia , Planejamento de Assistência ao Paciente , Síndrome do Intestino Curto/cirurgia , Fatores Etários , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Síndrome do Intestino Curto/reabilitação , Resultado do Tratamento
17.
Clin Med (Lond) ; 13(4): 407-10, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23908517

RESUMO

Lithium (Li) may cause multiple endocrinopathies, including hypercalcaemia, thyroid dysfunction and nephrogenic diabetes insipidus (NDI), but rarely in the same patient. The management of NDI remains a challenge. We report on a patient on long-term Li who had simultaneous NDI (paired serum and urine samples had abnormal osmolalities, typical of NDI, and treatment with parenteral desmopressin failed to affect urinary volume and serum osmolality), 'destructive' thyroiditis (hyperthyroidism, absent radioiodine uptake and absent thyrotrophin receptor antibodies) and primary hyperparathyroidism (compatible biochemistry, urine calcium excluding 'set point' anomalies and hypocalciuric hypercalcaemia, and normal parathyroid imaging). The thyroiditis resolved spontaneously and hypercalcaemia responded to reduction of Li dose. The NDI was unresponsive to amiloride, thiazides and ibuprofen in combination. However, urine output was reduced by 50% when a high dose of oral desmopressin was given. We conclude that Li-induced multiple endocrinopathy remains rare and, although NDI is difficult to manage, high dose oral desmopressin should be tried when other medications fail.


Assuntos
Desamino Arginina Vasopressina/administração & dosagem , Diabetes Insípido Nefrogênico/tratamento farmacológico , Lítio/efeitos adversos , Administração Oral , Adulto , Antidiuréticos/administração & dosagem , Diabetes Insípido Nefrogênico/induzido quimicamente , Diabetes Insípido Nefrogênico/metabolismo , Relação Dose-Resposta a Droga , Seguimentos , Humanos , Masculino
18.
Schizophr Res ; 258: 84-93, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37536174

RESUMO

BACKGROUND AND HYPOTHESES: Sleep disturbances are increasingly recognized as cooccurring with psychotic symptoms. The potential importance of this relationship is complicated when considering the effects of anxiety and depressive symptoms which commonly present in early-stage illness states. This study aimed to investigate the relationship between self-reported sleep disturbance on the development of attenuated psychotic symptoms (APS) cross-sectionally and longitudinally while adjusting for roles of anxiety and depressive symptoms. DESIGN: Eight-hundred and two help-seeking young people aged 12 to 25 years who engaged with our Australian early intervention services were included in the study (the "Transitions" cohort). Cross sectional mediation and cross-lagged longitudinal (12-month) mediation models were developed with outcomes being different APS domains. RESULTS: Only baseline excessive daytime sleepiness predicted later APS when accounting for previous APS, anxiety and depressive symptomatology. Cross sectionally, self-reported sleep disturbance showed both direct and indirect predictive relationships with all APS domains. Partial mediation through anxiety and depression was shown for unusual thought content, perceptual abnormalities, and disorganised speech, while full mediation through depression was shown for non-bizarre ideas. CONCLUSIONS: The specificity of the relationship between self-reported sleep disturbance on APS highlights the potential for different roles in mechanistic models of psychotic symptom expression. This further indicates the need for further experimental research to illuminate potential causal pathways. Future research should continue to use continuous, symptom level approaches across a range of timeframes to more accurately model the complex dynamics present in the sleep-psychosis relationship.


Assuntos
Transtornos Psicóticos , Transtornos do Sono-Vigília , Humanos , Adolescente , Depressão/epidemiologia , Depressão/complicações , Estudos Transversais , Austrália , Ansiedade/epidemiologia , Ansiedade/complicações , Transtornos Psicóticos/complicações , Transtornos Psicóticos/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/complicações , Sono
19.
Ir J Psychol Med ; 39(2): 196-206, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-32758309

RESUMO

OBJECTIVE: To explore the phenomenology of auditory verbal hallucinations (AVHs) in a clinical sample of young people who have a 'non-psychotic' diagnosis. METHODS: Ten participants aged 17-31 years with presentation of emotionally unstable personality disorder or post-traumatic stress disorder and frequent AVHs were recruited and participated in a qualitative study exploring their subjective experience of hearing voices. Photo-elicitation and ethnographic diaries were used to stimulate discussion in an otherwise unstructured walking interview. RESULTS: 'Non-psychotic' voices comprised auditory qualities such as volume and clarity. Participants commonly personified their voices, viewing them as distinct characters with which they could interact and form relationships. There appeared to be an intimate and unstable relationship between participant and voice, whereby voices changed according to the participants' mood, insecurities, distress and circumstance. Equally, participants reacted to provocation by the voice, leading to changes in mood and circumstance through emotional and physical disturbances. In contrast to our previous qualitative work in psychosis, voice hearing was not experienced with a sense of imposition or control. CONCLUSIONS: This phenomenological research yielded in-depth and novel accounts of 'non-psychotic' voices which were intimately linked to emotional experience. In contrast to standard reports of voices in disorders such as schizophrenia, participants described a complex and bi-directional relationship with their voices. Many other features were in common with voice hearing in psychosis. Knowledge of the phenomenology of hallucinations in non-psychotic disorders has the potential to inform future more successful management strategies. This report gives preliminary evidence for future research.


Assuntos
Transtorno da Personalidade Borderline , Transtornos Psicóticos , Esquizofrenia , Transtornos de Estresse Pós-Traumáticos , Adolescente , Alucinações/psicologia , Humanos , Transtornos Psicóticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/complicações
20.
Schizophr Res ; 243: 276-284, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32402606

RESUMO

BACKGROUND: The factors contributing to declining psychotic disorder transition rates in ultra-high-risk populations remain unclear. We examined the contribution of longitudinal changes in standard clinical treatment ('treatment as usual') to this decline. METHOD: An audit was conducted on 105 clinical files of patients who received standard care at a specialised ultra-high-risk service. The session notes of these files were quantified, allowing examination of treatment quantity, targets, psychotherapy, and medication. Differences in these aspects across patients' year of clinic entry were assessed. Variables with significant differences across years were examined using cox regression to assess their contribution to psychosis transition rates. RESULTS: Findings were that, as a function of patients' year of clinic entry, there were increases in: patients' number of sessions, cognitive behavioural therapy (CBT), problem and solving therapy. There was a relationship between baseline year cohort and psychosis transition rate, with lower rates observed in more recent cohorts. When changes in treatment between cohorts were adjusted for, the relationship between baseline year cohort and transition rate disappeared. The relationship between baseline year and transition rate was attenuated most by increases in CBT. CONCLUSION: Changes in standard treatment, particularly increases in CBT, may have contributed to the decline in psychosis risk observed in recent ultra-high-risk cohorts, although these variables do not fully explain this trend. Implications for clinical practice, prediction and intervention research are discussed. Future ultra-high-risk research should investigate the impact of other treatment factors, such as therapeutic alliance.


Assuntos
Terapia Cognitivo-Comportamental , Transtornos Psicóticos , Estudos de Coortes , Humanos , Psicoterapia , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/terapia , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa