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Dive into the research topics where Megan Johnston is active.

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Featured researches published by Megan Johnston.


Mens Sana Monographs | 2012

Stigma of Mental Illness-1: Clinical reflections

Amresh Shrivastava; Megan Johnston; Yves Bureau

Although the quality and effectiveness of mental health treatments and services have improved greatly over the past 50 years, therapeutic revolutions in psychiatry have not yet been able to reduce stigma. Stigma is a risk factor leading to negative mental health outcomes. It is responsible for treatment seeking delays and reduces the likelihood that a mentally ill patient will receive adequate care. It is evident that delay due to stigma can have devastating consequences. This review will discuss the causes and consequences of stigma related to mental illness.


Current Opinion in Psychiatry | 2010

Redefining outcome measures in schizophrenia: integrating social and clinical parameters

Amresh Shrivastava; Megan Johnston; Nilesh Shah; Yves Bureau

Purpose of review Schizophrenia is a complex neurobehavioral disorder for which there are many promising new treatments. There is, however, a discrepancy in outcome measure reports when they are obtained from patients, relatives, caregivers, or professionals, making it difficult to determine the level of recovery. This lack of agreement may result from limitations of the measurement tools themselves, which are not comprehensive and may be measuring different aspects of outcome. Alternatively, it could be that the conceptual understanding of outcome and recovery require development. Recent findings For various reasons, patients assessed as ‘recovered’ remain excluded from mainstream society. We are of the opinion that present outcome measures do not capture real-life situations. We propose that the concept of recovery be carefully defined and the gold standard of outcome should incorporate social and clinical parameters. We attempt to redefine recovery. Patients who have shown clinical improvement do not necessarily do well in everyday situations even though there is obvious clinical improvement. Therefore, it has been repeatedly argued that a consensus of recovery should be determined and that routine clinical practice should then adapt to the agreed criteria. Summary We argue that the outcome measures should be multidimensional and consist of at least two parameters: clinical remission and social outcome.


Indian Journal of Psychiatry | 2010

Effects of Duration of Untreated Psychosis on Long-term Outcome of People Hospitalized with First Episode Schizophrenia

Amresh Shrivastava; Nilesh Shah; Megan Johnston; Larry Stitt; Meghana Thakar; Gurusamy Chinnasamy

Duration of untreated psychosis (DUP) has emerged as a reliable predictor of outcome but continues to remain under scientific scrutiny. The present study examines the effect of differential periods of DUP on long-term outcome of first episode schizophrenia at Mumbai, India. This research was a prospective, 10-year follow-up naturalistic study. Hospitalized patients of first episode schizophrenia were selected and followed up. Results showed that the mean DUP was higher for a group which showed clinical recovery on Clinical Global Impression Scale [14.0 months (SD=8.0) in recovered and 10.8 months (SD=5.7) in non-recovered group (P=0.091)]. DUP was not found to be significantly associated with any of the end point parameters of good clinical or social outcome. Thus, this study found that DUP alone does not determine outcome status confirming the role of psychopathological heterogeneity.


Indian Journal of Psychiatry | 2013

Clinical risk of stigma and discrimination of mental illnesses: Need for objective assessment and quantification

Amresh Shrivastava; Yves Bureau; Nitika Rewari; Megan Johnston

Stigma and discrimination continue to be a reality in the lives of people suffering from mental illness, particularly schizophrenia, and prove to be one of the greatest barriers to regaining a normal lifestyle and health. Research advances have defined stigma and assessed its implications and have even examined intervention strategies for dealing with stigma. We are of the opinion that stigma is a potential clinical risk factor. It delays treatment seeking, worsens course and outcome, reduces compliance, and increases the risk of relapse; causing further disability, discrimination, and isolation even in persons who have accessed mental health services. The delay in treatment due to stigma causes potential complications like suicide, violence, harm to others, and deterioration in capacity to look after ones physical health. These are preventable clinical complications. In order to deal with the impact of stigma on an individual basis, it needs to be (i) assessed during routine clinical examination, (ii) assessed for quantification in order to obtain measurable objective deliverables, and (iii) examined if treatment can reduce stigma and its impact on individuals. New and innovative anti-stigma programs are required that are clinically driven in order to see the change in life of an individual by removing potential risks. The basic requirement for dealing with an individuals stigma perception/experience is its proper assessment for origin and impact in both a qualitative and quantitative manner. We further argue that quantification would allow for regular assessment and offer more effective intervention for patients. It will also be helpful in identifying modifiable social factors to enhance quality of care planning for management in hospitals and communities. The objective of quantification is to facilitate developing an approach to bring the assessment of stigma into clinical work and formulating customized strategies to deal with stigma at the patient level. It would be expected that the assessment of stigma would become a part of routine clinical assessment to identify barriers to outcome. This article discusses the need for quantification of patients’ experiences of mental illness stigma.


Indian Journal of Psychiatry | 2012

Atypical antipsychotics usage in long‑term follow‑up of first episode schizophrenia

Amresh Shrivastava; Megan Johnston; Kristen Terpstra; Larry Stitt; Nilesh Shah

Background: It is not clear if the role of antipsychotics in long-term clinical and functional recovery from schizophrenia is correlated. The pattern of use is a major aspect of pharmacotherapy in long-term follow-ups of schizophrenia. The aim of this study was to examine patterns of antipsychotic usage in patients with longstanding psychosis and their relationship to social outcomes. Materials and Methods: We conducted a cross-sectional study on a cohort from a long-term outcome study. Participants were 116 first episode schizophrenia patients from Mumbai, India, who had more than 80% compliance, as reported by relatives. Patients were assessed on antipsychotic medication use and on clinical and functional parameters. Results: There was a high compliance rate (72%). Most patients (77%) used atypical antipsychotics; only 10 (8.6%) patients were taking typical antipsychotics. There were no among-drug differences in the percentage of patients meeting the recommended dose: Clozapine (200–500 mg), Riseperidone (4.0–6.0 mg), Olanzapine (10–20 mg), Quetiapine (400–800 mg), Aripiprazole (15–30 mg), Ziprasidone (120–160 mg); an equivalent dosage of Chlorpromazine (300–600 mg) did not differ amongst any atypical antipsychotic subgroup. Also, we did not find any significant differences in recovery on Clinical Global Impression Severity scale (CGIS), Quality of Life (QOL), or Global Assessment of Functioning (GAF) between groups of antipsychotic drugs. Conclusion: This study shows that most patients suffering from schizophrenia, in a long-term follow-up, use prescribed atypical antipsychotics within the recommended limits. Also, the chlorpromazine equivalence dosages do not differ across antipsychotic medications. The outcomes on clinical and functional parameters are also similar across all second-generation antipsychotics.


Indian Journal of Psychiatry | 2010

Predictors of Long-term Outcome of First-episode Schizophrenia: A Ten-year Follow-up Study

Amresh Shrivastava; Nilesh Shah; Megan Johnston; Larry Stitt; Meghana Thakar

Objective: Schizophrenia is a severe mental disorder for which final outcomes continue to be unfavorable. The main objectives of this research were to examine and determine the baseline predictors of outcome status of first-episode schizophrenia in a long-term follow-up of ten years and of recovery ten years later. Materials and Methods: The study was carried out in a non-governmental, psychiatric hospital and participants consisted of patients available for assessment ten years following their initial diagnosis. Outcome was assessed on clinical and social parameters. Clinical measures of outcome included psychopathology, hospitalization, and suicidality. Social parameters included quality of life functioning, employability, interpersonal functioning, and the ability to live independently. Results: In our sample, mean positive symptoms’ score were reduced by more than 65% between baseline and endpoint. The percentage of reduction in scores of negative symptoms is much less than reduction in positive symptoms. It was observed that only 23-25% patients showed social recovery on two or three different parameters. Additionally, fewer negative symptoms, lower depression scores, and low levels of aggression at baseline predicted good outcome. A higher level of positive symptoms at baseline also predicted recovery. The two social variables that predicted later outcomes were initially high levels of work performance and the ability to live independently at baseline. Conclusions: Clinical information is not sufficient to make an accurate prediction of outcome status; rather, outcome depends upon multiple factors (including social parameters). A major implication of this research is the argument for moving toward a comprehensive assessment of outcome and to plan management accordingly. Bringing social outcome measures to the forefront and into the communities will allow for a more patient-centric approach. It also opens newer vistas for addressing the complex interaction of clinical and social parameters.


Neuropsychiatric Disease and Treatment | 2010

Persistent Suicide Risk in Clinically Improved Schizophrenia Patients: Challenge of the Suicidal Dimension

Amresh Shrivastava; Megan Johnston; Nilesh Shah; Marco Innamorati; Larry Stitt; Meghana Thakar; David Lester; Maurizio Pompili

Background Suicide is a major problem in schizophrenia, estimated to affect 9%–13% of patients. About 25% of schizophrenic patients make at least one suicide attempt in their lifetime. Current outcome measures do not address this problem, even though it affects quality of life and patient safety. The aim of this study was to assess suicidality in long-term clinically improved schizophrenia patients who were treated in a nongovernmental psychiatric treatment centre in Mumbai, India. Method Participants were 61 patients out of 200 consecutive hospitalized first-episode patients with schizophrenia diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders who were much improved on the Clinical Global Impression Scale-Improvement (CGI-I) scale at the endpoint of a 10-year follow-up. Clinical assessment tools included the Positive and Negative Syndrome Scale for Schizophrenia, CGI-I, Global Assessment of Functioning, and suicidality. Results Many of the patients, although clinically improved, experienced emerging suicidality during the 10-year follow-up period. All of the patients reported significant suicidality (ie, suicide attempts, suicidal crises, or suicidal ideation) at the end of the study, whereas only 83% had reported previous significant suicidality at baseline. No sociodemographic and clinical variables at baseline were predictive of suicidal status at the end of the 10-year follow-up. Conclusion Schizophrenia is a complex neurobehavioral disorder that appears to be closely associated with suicidal behavior. Adequate assessment and management of suicidality needs to be a continual process, even in patients who respond well to treatment.


Mens Sana Monographs | 2010

Weight-Gain in Psychiatric Treatment: Risks, Implications, and Strategies for Prevention and Management

Amresh Shrivastava; Megan Johnston

Weight-gain in psychiatric populations is a common clinical challenge. Many patients suffering from mental disorders, when exposed to psychotropic medications, gain significant weight with or without other side-effects. In addition to reducing the patients′ willingness to comply with treatment, this weight-gain may create added psychological or physiological problems that need to be addressed. Thus, it is critical that clinicians take precautions to monitor and control weight-gain and take into account and treat all problems facing an individual. In this review, we examine some of the key issues surrounding weight-gain in individuals suffering from mental disorders for contemporary practitioners in community clinics. We describe some factors known to make certain patients more susceptible to treatment-induced weight-gain and mechanisms implicated in this process. We also highlight a few psychological and pharmacological interventions that have proven effective in weight management. Importantly, we provide critical steps for management and prevention of weight-gain and related issues in the clinical practice of psychopharmacology.


Indian Journal of Psychiatry | 2011

Cannabis use and cognitive dysfunction

Amresh Shrivastava; Megan Johnston; Ming T. Tsuang

Byline: Amresh. Shrivastava, Megan. Johnston, Ming. Tsuang This review considers the effects of cannabis on cognitive functioning, in both short and long term. Although the general impression supported by many studies is that cannabis causes cognitive decline, particularly with long-term usage, some research suggests that this may not be the case. Nevertheless, certain specific neuropsychological parameters have been found to be affected. Most commonly and consistently reported are response time, prolongation of word viewing time, basic oculomotor deficit, residual verbal memory and executive functioning. The pathways to cognitive dysfunction are given particular focus, including the role of the central nervous system (CNS) cannabinoid system. Finally, the psychiatric effects of cannabis are considered in light of the idea that cognitive function may be the common denominator in the association between cannabis and psychotic disorders. Effect of Cannabis on Cognition Cannabis is one of the most commonly abused illicit drugs. The World Health Organization [sup][1] reports that almost 3% of the worlds adult population abuses cannabis, with many more individuals reporting less frequent use. Adolescents in particular consume high levels of cannabis, starting generally between 12 and 16 years of age. This is an important factor from a psychiatric and developmental point of view. [sup][2] Cannabis use is of important consideration in light of its recognized acute and long-term health effects. [sup][1],[3] Active compounds of cannabis, called cannabidols, have 64 active isomers, each having different effects on human health and behavior. Only one metabolite, tetrahydrocannabinol (THC), is reported to be an active metabolite responsive for its effects. [sup][4] Studies show that it induces both psychical and physical dependencies, [sup][5] but the perception of withdrawal is weak on account of its slow elimination. [sup][6] There is a widely held belief that cannabis is inert to the brain, [sup][7] and although the psychological consequences are quite evident, the population at large seems unconvinced. There is much debate about the nature of cannabis dependence, as it is considered non-addicting due to the absence of a withdrawal state. This presumption has also been proved wrong. [sup][6] The general impression supported by many studies is that cannabis causes cognitive decline, particularly with long-term usage. Majority of studies have suggested a significant cognitive decline in cannabis abusers compared to non-abusers and healthy controls. [sup][8],[9],[10] A report by Bartholomew et al. [sup][11] suggested that cannabis use has a detrimental effect on prospective memory ability in young adults but users may not be aware of these deficits. Cannabis is known to produce substantial acute effects on human cognition and visuomotor skills. Many recent studies additionally revealed rather long-lasting effects on basic oculomotor control, especially after chronic use. [sup][12] Even so, it is still unknown to what extent these deficits play a role in everyday tasks that strongly rely on an efficient saccade system, such as reading. Cannabis has a negative impact on cognition; however, the current body of research literature does not provide evidence of significant, long-term effects due to cannabis use. Several acute effects are noted and some are suggestive of negative mental health consequences. [sup][13] Evidence from both animal and human studies suggests that the severity of the effects of cannabis use on cognitive development is dependent on the age when cannabis use begins. [sup][14] One possible explanation is that those who begin cannabis use early in adolescence are more likely to become heavily dependent. It is plausible that chronic cannabis abuse will then interfere with educational and vocational training. From a more biological perspective, however, use of cannabis during critical developmental periods in the still maturing brain may induce persistent alterations in brain structure and brain function. …


Indian Journal of Psychiatry | 2014

Cannabis and psychosis: Neurobiology

Amresh Shrivastava; Megan Johnston; Kristen Terpstra; Yves Bureau

Cannabis is a known risk factor for schizophrenia, although the exact neurobiological process through which the effects on psychosis occur is not well-understood. In this review, we attempt to develop and discuss a possible pathway for the development of psychosis. We examine the neurobiological changes due to cannabis to see if these changes are similar to those seen in schizophrenic patients the findings show similarities; however, these mere similarities cannot establish a ‘cause-effect’ relationship as a number of people with similar changes do not develop schizophrenia. Therefore, the ‘transition-to-psychosis’ due to cannabis, despite being a strong risk factor, remains uncertain based upon neurobiological changes. It appears that other multiple factors might be involved in these processes which are beyond neurobiological factors. Major advances have been made in understanding the underpinning of marijuana dependence, and the role of the cannabinoid system, which is a major area for targeting medications to treat marijuana withdrawal and dependence, as well as other addictions is of now, it is clear that some of the similarities in the neurobiology of cannabis and schizophrenia may indicate a mechanism for the development of psychosis, but its trajectories are undetermined.

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Amresh Shrivastava

University of Western Ontario

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Larry Stitt

University of Western Ontario

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Amresh Srivastava

University of Western Ontario

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Robbie Campbell

University of Western Ontario

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Yves Bureau

University of Western Ontario

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