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Dive into the research topics where Olav Nielssen is active.

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Featured researches published by Olav Nielssen.


Australian and New Zealand Journal of Psychiatry | 2016

Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for the management of schizophrenia and related disorders.

Cherrie Galletly; David Castle; Frances Dark; Verity Humberstone; Assen Jablensky; Eoin Killackey; Jayashri Kulkarni; Patrick D. McGorry; Olav Nielssen; Nga Tran

Objectives: This guideline provides recommendations for the clinical management of schizophrenia and related disorders for health professionals working in Australia and New Zealand. It aims to encourage all clinicians to adopt best practice principles. The recommendations represent the consensus of a group of Australian and New Zealand experts in the management of schizophrenia and related disorders. This guideline includes the management of ultra-high risk syndromes, first-episode psychoses and prolonged psychoses, including psychoses associated with substance use. It takes a holistic approach, addressing all aspects of the care of people with schizophrenia and related disorders, not only correct diagnosis and symptom relief but also optimal recovery of social function. Methods: The writing group planned the scope and individual members drafted sections according to their area of interest and expertise, with reference to existing systematic reviews and informal literature reviews undertaken for this guideline. In addition, experts in specific areas contributed to the relevant sections. All members of the writing group reviewed the entire document. The writing group also considered relevant international clinical practice guidelines. Evidence-based recommendations were formulated when the writing group judged that there was sufficient evidence on a topic. Where evidence was weak or lacking, consensus-based recommendations were formulated. Consensus-based recommendations are based on the consensus of a group of experts in the field and are informed by their agreement as a group, according to their collective clinical and research knowledge and experience. Key considerations were selected and reviewed by the writing group. To encourage wide community participation, the Royal Australian and New Zealand College of Psychiatrists invited review by its committees and members, an expert advisory committee and key stakeholders including professional bodies and special interest groups. Results: The clinical practice guideline for the management of schizophrenia and related disorders reflects an increasing emphasis on early intervention, physical health, psychosocial treatments, cultural considerations and improving vocational outcomes. The guideline uses a clinical staging model as a framework for recommendations regarding assessment, treatment and ongoing care. This guideline also refers its readers to selected published guidelines or statements directly relevant to Australian and New Zealand practice. Conclusions: This clinical practice guideline for the management of schizophrenia and related disorders aims to improve care for people with these disorders living in Australia and New Zealand. It advocates a respectful, collaborative approach; optimal evidence-based treatment; and consideration of the specific needs of those in adverse circumstances or facing additional challenges.


Schizophrenia Research | 2011

Violence in first-episode psychosis: A systematic review and meta-analysis

Matthew Large; Olav Nielssen

BACKGROUND Violence towards others is a recognised complication of first-episode psychosis. AIMS To estimate the rate of violence and the associations with violence in first-episode psychosis. METHOD A systematic review and meta-analysis of 9 studies. RESULTS Pooled estimates of the proportion of patients with first-episode psychosis committing any violence, serious violence and severe violence were 34.5%, 16.6% and 0.6%, respectively. Violence of any severity was associated with involuntary treatment (OR=3.84), a forensic history (OR=3.28), hostile affect (OR=3.52), symptoms of mania (OR=2.86), illicit substance use (OR=2.33), lower levels of education (OR=1.99), younger age (OR=1.85), male sex (OR =1.61) and the duration of untreated psychosis (OR=1.56). Serious violence was associated with a forensic history (OR=4.42), the duration of untreated psychosis (OR=2.76) and total symptom scores (OR=2.05). Violence in the period after initiation of treatment for first-episode psychosis was associated with involuntary treatment (OR=5.71). CONCLUSIONS A substantial proportion of patients in first-episode psychosis commit an act of violence before presenting for treatment, including a number who commit an act of more serious violence causing injury to another person. However, severe violence resulting in serious or permanent injury to the victim is uncommon in this population.


Schizophrenia Bulletin | 2010

Rates of Homicide During the First Episode of Psychosis and After Treatment: A Systematic Review and Meta-analysis

Olav Nielssen; Matthew Large

The observation that almost half of the homicides committed by people with a psychotic illness occur before initial treatment suggests an increased risk of homicide during the first episode of psychosis. The aim of this study was to estimate the rates of homicide during the first episode of psychosis and after treatment. A systematic search located 10 studies that reported details of all the homicide offenders with a psychotic illness within a known population during a specified period and reported the number of people who had received treatment prior to the offense. Meta-analysis of these studies showed that 38.5% (95% confidence interval [CI] = 31.1%-46.5%) of homicides occurred during the first episode of psychosis, prior to initial treatment. Homicides during first-episode psychosis occurred at a rate of 1.59 homicides per 1000 (95% CI = 1.06-2.40), equivalent to 1 in 629 presentations. The annual rate of homicide after treatment for psychosis was 0.11 homicides per 1000 patients (95% CI = 0.07-0.16), equivalent to 1 homicide in 9090 patients with schizophrenia per year. The rate ratio of homicide in the first episode of psychosis in these studies was 15.5 (95% CI = 11.0-21.7) times the annual rate of homicide after treatment for psychosis. Hence, the rate of homicide in the first episode of psychosis appears to be higher than previously recognized, whereas the annual rate of homicide by patients with schizophrenia after treatment is lower than previous estimates. Earlier treatment of first-episode psychosis might prevent some homicides.


Australian and New Zealand Journal of Psychiatry | 2011

Risk Factors for Suicide Within a Year of Discharge from Psychiatric Hospital: A Systematic Meta-Analysis

Matthew Large; Swapnil Sharma; Elisabeth Cannon; Chris Ryan; Olav Nielssen

Background: The increased risk of suicide in the period after discharge from a psychiatric hospital is a well-recognized and serious problem. Objective: The aim of this study was to establish the risk factors for suicide in the year after discharge from psychiatric hospitals and their usefulness in categorizing patients as high or low risk for suicide in the year following discharge. Method: A systematic meta-analysis of controlled studies of suicide within a year of discharge from psychiatric hospitals. Results: There was a moderately strong association between both a history of self-harm (OR = 3.15) and depressive symptoms (OR = 2.70) and post-discharge suicide. Factors weakly associated with post-discharge suicide were reports of suicidal ideas (OR = 2.47), an unplanned discharge (OR = 2.44), recent social difficulty (OR = 2.23), a diagnosis of major depression (OR = 1.91) and male sex (OR = 1.58). Patients who had less contact with services after discharge were significantly less likely to commit suicide (OR = 0.69). High risk patients were more likely to commit suicide than other discharged patients, but the strength of this association was not much greater than the association with some individual risk factors (OR = 3.94, sensitivity = 0.40, specificity = 0.87). Conclusions: No factor, or combination of factors, was strongly associated with suicide in the year after discharge. About 3% of patients categorized as being at high risk can be expected to commit suicide in the year after discharge. However, about 60% of the patients who commit suicide are likely to be categorized as low risk. Risk categorization is of no value in attempts to decrease the numbers of patients who will commit suicide after discharge.


Acta Psychiatrica Scandinavica | 2011

Systematic review and meta-analysis of the clinical factors associated with the suicide of psychiatric in-patients

Matthew Large; Glen Smith; Swapnil Sharma; Olav Nielssen; Swaran P. Singh

Large M, Smith G, Sharma S, Nielssen O, Singh SP. Systematic review and meta‐analysis of the clinical factors associated with the suicide of psychiatric in‐patients.


Schizophrenia Research | 2009

The relationship between the duration of untreated psychosis and outcome in low-and-middle income countries: A systematic review and meta analysis

Saeed Farooq; Matthew Large; Olav Nielssen; Waquas Waheed

BACKGROUND The duration of untreated psychosis (DUP) is defined as the period between the onset of symptoms of psychosis and the start of antipsychotic treatment. Delay in the initiation of treatment, resulting in a long DUP, is associated with a poor prognosis in high-income (HI) countries. It is not known if longer DUP is associated with poor outcomes in Low and Middle Income (LAMI) countries, where schizophrenia might have a more benign course. METHODS A systematic review and meta-analysis of studies from LAMI countries that reported an association between DUP and response to treatment, measures of disability and mortality. The association between DUP, symptoms and cognitive function at presentation were also examined. FINDINGS Meta analysis of five studies that reported the association between DUP and the reduction in total symptoms scores after treatment found a significant negative correlation between DUP and improvement in symptoms after treatment (r=-0.290, 95% CI=-0.483 to -0.069, z=-2.559, p<0.011). Prolonged DUP was also associated with increased levels of disability. One study reported that longer DUP was associated with a higher mortality in the following decade. CONCLUSIONS Delay in the initial initiation of treatment for psychosis is associated with a poorer response to treatment and increased levels of disability in LAMI countries.


Schizophrenia Bulletin | 2009

Major Self-mutilation in the First Episode of Psychosis

Matthew Large; Nicholas Babidge; Doug Andrews; Philip Storey; Olav Nielssen

Major self-mutilation (MSM) is a rare but catastrophic complication of severe mental illness. Most people who inflict MSM have a psychotic disorder, usually a schizophrenia spectrum psychosis. It is not known when in the course of psychotic illness, MSM is most likely to occur. In this study, the proportion of patients in first episode of psychosis (FEP) was assessed using the results of a systematic review of published case reports. Histories of patients who had removed an eye or a testicle, severed their penis, or amputated a portion of a limb and were diagnosed with a schizophrenia spectrum psychosis were included. A psychotic illness was documented in 143 of 189 cases (75.6%) of MSM, of whom 119 of 143 (83.2%) were diagnosed with a schizophrenia spectrum psychosis. The treatment status of a schizophrenia spectrum psychosis could be ascertained in 101 of the case reports, of which 54 were in the FEP (53.5%, 95% confidence interval = 43.7%-63.2%). Patients who inflict MSM in FEP exhibited similar symptoms to those who inflict MSM later in their illness. Acute psychosis, in particular first-episode schizophrenia, appears to be the major cause of MSM. Although MSM is extremely uncommon, earlier treatment of psychotic illness may reduce the incidence of MSM.


Australasian Psychiatry | 2010

Clinical decisions in psychiatry should not be based on risk assessment

Chris Ryan; Olav Nielssen; Michael Paton; Matthew Large

Objective: Risk assessments that place patients in high or low risk categories have been widely adopted by mental health services in an attempt to reduce the harms associated with psychiatric disorders. This paper examines the effects of categorization based on the results of a risk assessment. Methods: The violence prediction instrument derived from the MacArthur Study of Mental Disorder and Violence was used to illustrate the nature and effects of risk assessment and the consequent categorization of patients. Results: The majority of patients categorized as being at high risk will not commit any harmful acts. Conclusions: Patients who are classified as high risk share the cost of efforts to reduce harm in the form of additional treatment and restrictions, although the majority will not go on to commit a harmful act. Clinical decisions made on the basis of risk assessment also divert resources away from patients classified as low risk, even though a significant proportion do go on to a commit harmful act. We argue that psychiatric professionals should discuss the risks of treatment and of non-treatment with patients (or with their substitute decision-makers) and should maintain a duty to warn about the consequences of not having treatment. However, assessment of risk of harm should not form the basis for clinical decision making. We should aim to provide optimal care according to the treatment needs of each patient, regardless of the perceived risk of adverse events.


The Journal of Clinical Psychiatry | 2012

Tobacco use before, at, and after first-episode psychosis: a systematic meta-analysis.

Nicholas Myles; Hannah Newall; Jackie Curtis; Olav Nielssen; David Shiers; Matthew Large

OBJECTIVE Patients with first-episode psychosis have a high prevalence of tobacco use. We aimed to examine the prevalence and course of tobacco use during early psychosis using meta-analysis. DATA SOURCES Systematic search of MEDLINE (1948-2011), Embase (1947-2011), CINAHL (1984-2011), PsycINFO (1967-2011), and ISI Web of Science (1900-2011) using the search terms [psychosis OR schizophrenia] AND [tobacco OR smoking OR nicotine]. STUDY SELECTION We located 10 studies reporting the age at initiation of daily tobacco use and the age at onset of psychosis, 31 studies reporting prevalence of tobacco use in patients with first-episode psychosis, 10 studies comparing smoking to age-/gender-matched controls, and 7 studies reporting prevalence of tobacco use at intervals after treatment. DATA EXTRACTION The following data were extracted: age at initiation of daily tobacco use and at onset of psychosis, the proportion of patients with first-episode psychosis who used tobacco, the proportion of the general population who used tobacco, and the proportion of patients with psychosis who used tobacco at various intervals after initiation of antipsychotic treatment. RESULTS The pooled estimate for the interval between initiation of tobacco use and the onset of psychosis was 5.3 years (standardized mean difference = 0.85). The estimated prevalence of tobacco users in first episode of psychosis is 58.9% (95% CI, 54.3%-63.4%). There is a strong association between first-episode psychosis and tobacco use (OR = 6.04; 95% CI, 3.03-12.02) compared with healthy controls. The prevalence of tobacco use at intervals between 6 and 120 months after treatment remained unchanged (OR = 0.996; 95% CI, 0.907-1.094). CONCLUSIONS Patients with first-episode psychosis tend to have smoked for some years prior to the onset of psychosis, have high prevalence of tobacco use at the time of presenting for treatment, and are much more likely to smoke than aged-matched controls. Their apparent difficulty in quitting has implications for tobacco cessation programs and efforts to reduce cardiovascular disease among people with mental illness.


PLOS ONE | 2015

Prevalence and Risk Factors of Violence by Psychiatric Acute Inpatients: A Systematic Review and Meta-Analysis.

Laura Iozzino; Clarissa Ferrari; Matthew Large; Olav Nielssen; Giovanni de Girolamo

Background Violence in acute psychiatric wards affects the safety of other patients and the effectiveness of treatment. However, there is a wide variation in reported rates of violence in acute psychiatric wards. Objectives To use meta-analysis to estimate the pooled rate of violence in published studies, and examine the characteristics of the participants, and aspects of the studies themselves that might explain the variation in the reported rates of violence (moderators). Method Systematic meta-analysis of studies published between January 1995 and December 2014, which reported rates of violence in acute psychiatric wards of general or psychiatric hospitals in high-income countries. Results Of the 23,972 inpatients described in 35 studies, the pooled proportion of patients who committed at least one act of violence was 17% (95% confidence interval (CI) 14–20%). Studies with higher proportions of male patients, involuntary patients, patients with schizophrenia and patients with alcohol use disorder reported higher rates of inpatient violence. Conclusion The findings of this study suggest that almost 1 in 5 patients admitted to acute psychiatric units may commit an act of violence. Factors associated with levels of violence in psychiatric units are similar to factors that are associated with violence among individual patients (male gender, diagnosis of schizophrenia, substance use and lifetime history of violence).

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Matthew Large

University of New South Wales

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Glen Smith

Royal Prince Alfred Hospital

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Robert A. Hayes

University of Western Sydney

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