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Dive into the research topics where Thomas S. Ehmann is active.

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Featured researches published by Thomas S. Ehmann.


Journal of Nervous and Mental Disease | 2001

Violence in treatment resistant psychotic inpatients

Thomas S. Ehmann; Geoffrey N. Smith; Aiko Yamamoto; Natalia Mccarthy; Deborah Ross; Tin Au; Sean W. Flynn; Siemion Altman; William G. Honer

This study sought to: a) ascertain the effect on rates of violence by varying its operational definition and b) compare characteristics of violent and nonviolent patients. Aggressive behavior was recorded daily for every patient (N = 78) during a 2-year period. Standardized rating scales were used to rate psychopathology and functioning. Almost two thirds of patients were aggressive to others, and 26% violently assaulted another person. Official incident reports underestimated rates of violence to others, self- harm, and property damage. Multivariate predictive models that greatly improved accuracy over base rates showed that violent patients tended to be female, schizophrenic (nonparanoid type), and abusive of alcohol before admission. Violence is more common in treatment resistant psychotic inpatients than suggested by incident reports. Standardized definitions of violence are urged in order to accurately study its prevalence and correlates. Models combining both historical/demographic and clinical data may enhance prediction of violence.


Psychiatric Services | 2011

The assessment of symptom severity and functional impairment with DSM-IV axis V.

Geoffrey N. Smith; Thomas S. Ehmann; Sean W. Flynn; G. William MacEwan; Karen Tee; Lili C. Kopala; Allen E. Thornton; Christian H. Schenk; William G. Honer

OBJECTIVE The Global Assessment of Functioning scale (GAF) is included as axis V in the DSM-IV multiaxial diagnostic system. The GAF is simple to administer and routinely used in treatment planning and as a measure of program performance. The GAF assesses both symptom severity and functional impairment, but the resultant rating provides no information about the contribution of each of these domains. This study aimed to improve the clinical utility of the GAF by creating subscales. METHODS The authors divided the scale into its two principal domains: descriptors of social and occupational functioning (SOFAS) and descriptors of symptoms (GAF minus SOFAS descriptors). These and other measures of symptoms and functioning were used to assess 407 patients while acutely psychotic and again after treatment. RESULTS Symptom scores were of greater severity than functional impairment scores in most cases. Because of this, the GAF score tended to reflect symptom severity rather than functional impairment. The symptom rating was more strongly correlated with measures of positive symptoms, and the functional rating had higher associations with negative symptoms and functional impairment. Both scales were good indicators of clinical change. CONCLUSIONS Findings indicate that GAF ratings for patients with psychosis tend to reflect symptom severity rather than functional impairment. Splitting the GAF into two parts resulted in greater discrimination for this patient group yet retained ease of administration.


Schizophrenia Research | 2001

Low birthweight in schizophrenia: prematurity or poor fetal growth?

Geoffrey N. Smith; Sean W. Flynn; Natalia Mccarthy; Barbara Meistrich; Thomas S. Ehmann; G.William MacEwan; Simeon Altman; Lili C. Kopala; William G. Honer

In the general population, low birthweight (LBW) is associated with neurological and psychological problems during childhood and adolescence. LBW may result from premature birth or poor fetal growth, and the independent effects of these two events on childhood development are not fully understood. The rate of low weight births is increased in schizophrenia and is associated with social withdrawal during childhood and an early onset of illness. However, it is unclear whether this LBW reflects poor fetal growth or premature birth, or whether these two risk factors have distinct implications for childhood functioning and age at onset of schizophrenia. Subjects included 270 patients with schizophrenia for whom a detailed history of obstetric events could be obtained. The rate of low weight births was high and was associated with poorer premorbid functioning and an earlier age at illness onset. The rate of both premature births and poor fetal growth was high relative to the normal population. Prematurity, but not poor fetal growth, was associated with premorbid social withdrawal and an early age at illness onset. Poor fetal growth, but not prematurity, was associated with low educational achievement. These results suggest that poor fetal growth and prematurity are associated with distinct patterns of childhood maladjustment in individuals who develop schizophrenia.


Schizophrenia Research | 2012

Hippocampal volume and the brain-derived neurotrophic factor Val66Met polymorphism in first episode psychosis

Geoffrey N. Smith; Allen E. Thornton; Donna J. Lang; G. William MacEwan; Thomas S. Ehmann; Lili C. Kopala; Karen Tee; Gillian Shiau; Aristotle N. Voineskos; James L. Kennedy; William G. Honer

INTRODUCTION Small hippocampi and impaired memory are common in patients with psychosis and brain-derived neurotrophic factor (BDNF) plays a critical role in hippocampal neuroplasticity and memory. A common BDNF allele (Val66Met) has been the focus of numerous studies but results from the few BDNF-imaging studies are complex and contradictory. The objective of this study was to determine the association between Val66Met and hippocampal volume in patients with first episode psychosis. Secondary analyses explored age-related associations and the relationship between Val66Met and memory. METHOD Hippocampal volume and BDNF genotyping were obtained for 58 patients with first-episode psychosis and 39 healthy volunteers. Patients were recruited from an early psychosis program serving a catchment-area population. RESULTS Hippocampal volume was significantly smaller in patients than controls (F(1,92)=4.03, p<0.05) and there was a significant group-by-allele interaction (F(1,92)=3.99, p<0.05). Hippocampal volume was significantly smaller in patients than controls who were Val-homozygotes but no group differences were found for Met carriers. Findings were not affected by diagnosis, antipsychotic medication, or age, and there was no change in hippocampal volume during a one-year follow-up. Val-homozygous patients had worse immediate and delayed memory than their Met counterparts. CONCLUSIONS Results suggest the effects of the BDNF Val66Met allele may be different in patients with psychosis than in healthy adults. Hippocampal volume in patient and control Met allele carriers was very similar suggesting that illness-related factors have minimal influence in this group. In contrast, Val homozygosity was related to smaller hippocampi and poorer memory functioning only in patients with psychosis.


Schizophrenia Research | 2009

Predictors of starting to smoke cigarettes in patients with first episode psychosis.

Geoffrey N. Smith; Hubert Wong; G. William MacEwan; Lili C. Kopala; Thomas S. Ehmann; Allen E. Thornton; Donna J. Lang; Alasdair M. Barr; Ric M. Procyshyn; Jehanine C. Austin; Sean W. Flynn; William G. Honer

INTRODUCTION Cigarette smoking is common in psychotic disorders and may be initiated in an attempt to control features of illness. However, genetic, obstetric and early life conditions are risks for starting to smoke in the general population but their role in psychotic patients is unclear. METHOD Smoking history and the putative predictors of starting to smoke were assessed in a community-wide sample of 115 first episode psychosis patients. The proportion that initiated smoking was compared with that from population surveys and the impact of risk factors was assessed within the patient sample. RESULTS Most patients began smoking before illness onset and the proportion who initiated smoking was significantly high by the onset of a functional decline. Gestational tobacco exposure was a risk for smoking and was also associated with low birthweight, poor academic achievement, and obesity. Low familial socioeconomic position but not familial psychiatric problems also predicted smoking initiation. DISCUSSION In most cases, smoking preceded illness onset and was not a response to early features of illness. General population predictors of starting to smoke were also associated with smoking initiation in psychotic patients. Of these risks, exposure to tobacco during gestation is noteworthy in that it affects brain development and is associated with cognitive, behavioral, psychiatric and general health problems. In addition, nicotine interacts with other substances of abuse. The initiation of smoking before illness onset and the association with developmental problems raises the question of whether cigarette smoking influences some aspects of illness in patients with psychosis.


Schizophrenia Research | 2010

Prenatal tobacco exposure in first-episode psychosis

Geoffrey N. Smith; G. William MacEwan; Lili C. Kopala; Thomas S. Ehmann; Kim Good; Allen E. Thornton; Heather Neilson; Donna J. Lang; Alasdair M. Barr; William G. Honer

Recent research findings leave no reasonable doubt that prenatal tobacco exposure (PTE) impairs fetal brain development (Slotkin, 2008). Smoking also impairs placental functioning and leads to fetal undernourishment and a dose-dependent restriction in growth (Pringle et al., 2005). Maternal smoking also results in fetal glucocorticoid over-activity and elevated stress hormones in newborns (Varvarigou et al., 2006). Finally, maternal smoking compromises fetal immune-system development and results in long-term suppression of the immune response (Basta et al., 2000). The negative consequences of PTE for health, cognition and behavior during childhood and beyond are well documented (Cornelius and Day, 2009). Recent findings suggest that PTE may also increase the risk for psychosis (Spauwen et al., 2004; Zammit et al., 2009). Despite strong evidence for the neuroteratogenic effects of nicotine, few studies have assessed the risks associated with PTE in psychiatric patients. We recently reported that cigarette smokers with firstepisode psychosis (FEP) tended to start smoking before the onset of psychosis and that PTE was a significant predictor of who would start smoking (Smith et al., 2009). We also found that PTEwas associatedwith lower birthweight, poor academic achievement and obesity. In order to verify these results and explore other ramifications of PTE, we repeated our analyses in a second FEP sample then combined the two groups to further explore the impact of PTE. We predicted that obstetrical,


Neuropsychiatric Disease and Treatment | 2017

Verbal memory improvement in first-episode psychosis APOE- ε4 carriers: a pleiotropic effect?

Fidel Vila-Rodriguez; Donna J. Lang; Heather A. Baitz; Kristina Gicas; Allen E. Thornton; Thomas S. Ehmann; Geoff Smith; Alasdair M. Barr; Ivan J. Torres; Lili C. Kopala; G. William MacEwan; Daniel Müller; James L. Kennedy; William G. Honer

Background Verbal memory impairment is a core feature in schizophrenia even at early stages of the disease, but its etiopathogenesis is not fully understood. The APOE-ε4 is the main genetic risk factor for late-onset Alzheimer’s disease. Our primary goal was to ascertain whether APOE-ε4 status had a pleiotropic effect in early stages of the illness. Participants and methods A total of 86 first-episode psychosis (FEP) outpatients and 39 healthy volunteers were recruited. Demographic and clinical data, APOE genotyping, and a neuropsychological test battery including the California Verbal Learning Test – second edition (CVLT-II) were administered and assessed at study entry and at 1-year follow-up. Data were analyzed using mixed-model repeated measures, where the dependent variable was verbal memory indexed by California Verbal Learning Test (CVLT) Trials 1–5 total recall score. Results FEP-APOE-ε4 carriers and FEP-APOE-ε4 noncarriers had similar symptom severity, clinical outcomes, premorbid and current intelligence quotient, and exposure to antipsychotics. There was a main effect of group on CVLT 1–5 (FEP =43.30 vs control =58.25; F[1, 119.7]=42.97; P<0.001) as well as an APOE-ε4 by group by time (F[4, 116.2]=2.73, P=0.033) interaction with only FEP-APOE-ε4 carriers showing improved verbal memory at follow-up. Conclusion Our study is the first to report improvement in verbal memory in persons afflicted by FEP who are APOE-ε4 carriers and replicates the prominent verbal memory deficits present in FEP. Our work provides further evidence pointing to an antagonistic pleiotropic effect of APOE-ε4 in neuropsychiatric disorders. Our results merit further research into antagonistic pleiotropic effects in schizophrenia.


Comprehensive Psychiatry | 1995

Routine Assessment of Patient Progress: A Multiformat, Change-Sensitive Nurses' Instrument for Assessing Psychotic Inpatients

Thomas S. Ehmann; Elaine Higgs; Geoffrey N. Smith; Tin Au; S. Altman; Derick Lloyd; William G. Honer


Comprehensive Psychiatry | 2001

Multidimensional assessment of psychosis: A factor-analytic validation study of the routine assessment of patient progress

Thomas S. Ehmann; Stephen G. Holliday; G.W. MacEwan; Geoffrey N. Smith


Schizophrenia Research | 1995

Clozapine, risperidone and typical antipsychotics in severely ill patients with schizophrenia

S. Altman; William G. Honer; G. William MacEwan; Lili C. Kopala; Sherri Chisholm-Hay; Geoffrey N. Smith; Thomas S. Ehmann; M. Lang

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Geoffrey N. Smith

University of British Columbia

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William G. Honer

University of British Columbia

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Lili C. Kopala

University of British Columbia

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G. William MacEwan

University of British Columbia

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Sean W. Flynn

University of British Columbia

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Donna J. Lang

University of British Columbia

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Alasdair M. Barr

University of British Columbia

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