christian schuetz | University of British Columbia (original) (raw)

Papers by christian schuetz

Research paper thumbnail of Mental disorder, service use, and barriers to care among 500 homeless people in 3 different urban settings

Social Psychiatry and Psychiatric Epidemiology, Jan 9, 2013

Research paper thumbnail of Columbia, Canada: Role of Trauma and Incarceration Stimulants and Cannabis Use Among a Marginalized Population in British

High rates of substance use, especially cannabis and stimulant use, have been associated with hom... more High rates of substance use, especially cannabis and stimulant use, have been associated with homelessness, exposure to trauma, and involvement with the criminal justice system. This study explored differences in substance use (cannabis vs. stimulants) and associations with trauma and incarceration among a homeless population. Data were derived from the BC Health of the Homeless Study (BCHOHS), carried out in three cities in British Columbia, Canada. Measures included sociodemographic information, the Maudsley Addiction Profile (MAP), the Childhood Trauma Questionnaire (CTQ), and the Mini International Neuropsychiatric Interview (MINI) Plus. Stimulant users were more likely to be female (43%), using multiple substances (3.2), and engaging in survival sex (14%). Cannabis users had higher rates of lifetime psychotic disorders (32%). Among the incarcerated, cannabis users had been subjected to greater emotional neglect ( p < .05) and one in two cannabis users had a history of lifeti...

Research paper thumbnail of Mental disorder, service use, and barriers to care among 500 homeless people in 3 different urban settings

Social Psychiatry and Psychiatric Epidemiology, 2013

Research paper thumbnail of Effects of Irritability on Craving before and after Cue Exposure in Abstinent Alcoholic Inpatients: Experimental Data on Subjective Response and Heart Rate

Neuropsychobiology, 2002

Objective: Irritability is often linked with problem drinking. The aim of this study is to examin... more Objective: Irritability is often linked with problem drinking. The aim of this study is to examine the possible influence of irritability on craving induced by a cue-exposure paradigm. Methods: 30 male abstinent alcoholic inpatients of the Psychiatric Hospital of Munich University, Germany gave answers to a series of personality questionnaires. Results of this study concerning the impact of aggressivity on craving for alcohol has recently been published. In this study, the subjects were subdivided into a low- and a high-irritable group based on their scores on the irritability subscale of the Buss-Durkee Hostility Inventory and were exposed to alcohol cues. Craving was measured by means of the Alcohol Craving Questionnaire (ACQ) and Visual Analogue Scales (VAS). The heart rate was also assessed throughout the whole process. ANCOVA for repeated measurement was employed to evaluate the data – irritability disposition as the between-subject factor and the experimental manipulation (abs...

Research paper thumbnail of Is exposure to childhood maltreatment associated with adult psychological distress among adult intravenous drug user?

Mental Health and Substance Use, 2013

Research paper thumbnail of Factors associated with exposure to hepatitis B virus in injection drug users

Drug and Alcohol Dependence, 2006

This study was undertaken to describe factors associated with exposure to the hepatitis B virus (... more This study was undertaken to describe factors associated with exposure to the hepatitis B virus (HBV) in treated injection drug users to better aim prevention and care in high risk subgroups. The naturalistic study was conducted in Munich, Germany, and 1018 patients who ever shared needles admitted for opioid detoxification were included. Sociodemographic, drug and drug treatment related variables and the virological status (HCV, HIV) were included in the bivariate and multiple logistic regression analysis. Sera were tested positive for antibodies against HBc in 40.2%, against HCV in 60.9%, and against HIV in 4.7% of patients. Older age, living without partner, longer duration of IDU, positive drug treatment history, imprisonment, emergency treatment, daily alcohol consumption, type of opioid dependency, and being positive for anti-HCV or anti-HIV were significant individual factors associated with positive anti-HBc-serology. Using multiple logistic regression history of imprisonment and being positive for anti-HCV remained independently associated with positive anti-HBc-serology. HBV-infection in IDUs should alert for simultaneous HCV-infection. Contacts to the criminal justice system are to be used for HBV prevention programs, including vaccination when indicated. Prevention programs should be implemented early in or even before the begin of a drug career.

Research paper thumbnail of The Association Between Childhood Maltreatment Subtypes and Current Suicide Risk Among Homeless Men and Women

Child Maltreatment, 2012

This study explored self-reports of five childhood maltreatment (CM) subtypes and their associati... more This study explored self-reports of five childhood maltreatment (CM) subtypes and their associations with current suicide risk in a sample of 500 homeless persons. Participants completed the Childhood Trauma Questionnaire and the Mini-International Neuropsychiatric Interview. Individual, unique, and cumulative associations of CM subtypes and subtype combinations with suicide risk (no vs. low vs. moderate/high) were examined. In multivariate analyses, four of the five CM subtypes were associated with suicide risk in individual models, but not in a model that included all CM subtypes. The strongest associations were found for reports of multitype CM involving all five subtypes. Mental disorders and female sex were independently associated with suicide risk. Clinicians working with CM victims should be aware that homeless clients are likely to report multitype maltreatment and should assess a variety of CM experiences. Future studies need to further examine multitype maltreatment and s...

Research paper thumbnail of Smoking and predictors of nicotine dependence in a homeless population

To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and ... more To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and to investigate trends for demographic and clinical characteristics across different levels of nicotine dependence (nonsmokers vs. lowly dependent smokers vs. highly dependent smokers). A cross-sectional study of 489 homeless men and women in 3 Canadian cities. Each subject was assessed using structured clinical interviews and the Fagerström Test for Nicotine Dependence (FTND). Cochran-Armitage trend tests were applied to determine unadjusted trends in sociodemographic and clinical variables across levels of nicotine dependence. A generalized logit model was computed to adjust for potential confounding. The mean age was 37.9 years; 39.2% of the participants were women. About 80.8% were current smokers; the mean FTND score was 5.0. Although no significant differences were found between nonsmokers and smokers with low nicotine dependence, smokers with high nicotine dependence were only half as likely as nonsmokers to be Aboriginal, were 2.39 times more likely to have ever been incarcerated, and 2.44 times more likely to have current drug dependence. There were significant trends for the use of cocaine, opioids, and alcohol, with nonsmokers having the lowest and highly dependent smokers having the highest rates of using these substances. Available public health smoking cessation treatment opportunities should be made available within health care services for the homeless. There is also a need for developing and implementing tobacco dependence treatment programs, which are accessible and tailored to meet the needs of this specific population, accounting for polysubstance use and concurrent substance dependence and mental health disorders.

Research paper thumbnail of M: The association between childhood maltreatment subtypes and current suicide risk amonghomeless men and women

This study explored self-reports of five childhood maltreatment (CM) subtypes and their associati... more This study explored self-reports of five childhood maltreatment (CM) subtypes and their associations with current suicide risk in a sample of 500 homeless persons. Participants completed the Childhood Trauma Questionnaire and the Mini-International Neuropsychiatric Interview. Individual, unique, and cumulative associations of CM subtypes and subtype combinations with suicide risk (no vs. low vs. moderate/high) were examined. In multivariate analyses, four of the five CM subtypes were associated with suicide risk in individual models, but not in a model that included all CM subtypes. The strongest associations were found for reports of multitype CM involving all five subtypes. Mental disorders and female sex were independently associated with suicide risk. Clinicians working with CM victims should be aware that homeless clients are likely to report multitype maltreatment and should assess a variety of CM experiences. Future studies need to further examine multitype maltreatment and s...

Research paper thumbnail of Mental disorders in ecstasy users: a prospective-longitudinal investigation

Drug and Alcohol Dependence, 2002

Objectives: To investigate the relationship between ecstasy use and mental disorders in a represe... more Objectives: To investigate the relationship between ecstasy use and mental disorders in a representative sample of adolescents and young adults. Method: Data for this investigation were drawn from the Early Developmental Stages of Psychopathology (EDSP) study, an epidemiological Á/longitudinal study in which 14 Á/24 year-olds were examined prospectively over a period of about 4 years. Results are based on N 0/2462 participants who completed the whole study period and for whom drug use behavior could be determined. Results: (1) Ecstasy users, compared with non-users, were at significantly increased risk of DSM-IV substance related disorders, including alcohol use disorders (52.6 vs. 15.6%; OR0/5.6, 95% CI 0/3.8 Á/8.1). Further, ecstasy users also had a higher risk of alcohol use disorders, when compared with users of other illicit substances (52.6 vs. 40.3%; OR 0/1.7, 95% CI 0/1.1 Á/2.4). (2) Ecstasy users had significantly higher rates for almost all DSM-IV mental disorders examined when compared with non-users (any non-substance use disorder: 68.7 vs. 44.5%; OR0/3.1, 95% CI0/2.1 Á/4.4) and compared with users of other illicit drugs (any non substance use disorder: 68.7 vs. 55.5%; OR 0/1.8, 95% CI 0/1.2 Á/2.6). (3) Ecstasy users also reported significantly higher rates of prescription medicine use, though they did not use more medical services than non-drug users. (4) Analyses of temporal patterns of ecstasy use and disorder onset revealed that the first use of ecstasy was secondary to the onset of DSM-IV mental disorders in the majority of cases. Still, subjects with mental disorders at baseline also showed a significantly increased risk for initiation of ecstasy use during the 4-year follow-up period. Conclusions: Care should be taken in cross sectional studies in interpreting mental disorder signs and symptoms merely as a consequence of ecstasy use, as ecstasy use might be associated with the use of multiple substances, and onset of mental disorder is more likely to precede rather than to follow use of ecstasy and related substances.

Research paper thumbnail of Role of Aggressivity on Reactivity and Craving before and after Cue Exposure in Recently Detoxified Alcoholics: Results from an Experimental Study

European Addiction Research, 2001

The role of aggressivity and cue exposure in induction of craving were investigated in a clinical... more The role of aggressivity and cue exposure in induction of craving were investigated in a clinical setting. Thirty abstinent alcoholic patients were divided into a low and a high aggressive group based on scores on the physical aggression subscale of the Buss-Durkee Hostility Inventory and exposed to alcohol cues. Craving was measured by means of the Alcohol Craving Questionnaire (ACQ) and Visual Analogue Scales (VAS). Important findings are: (1) main effects of aggressivity on ‘emotionality’, ‘purposefulness’ and ‘expectancy’ of ACQ were very significant; (2) on ‘drinking intention’ and ‘craving for alcohol’ of VAS, aggressivity and cue exposure showed a significant interaction; (3) the main effect of cue exposure on heart rate also reached a significance level of 0.007. The results were discussed in the context of the Classical, Operant Conditioning Theory, the Cognitive Craving Theory of Tiffany, Gilbert’s STAR Model, and the Self-Medication Hypothesis

Research paper thumbnail of Mental health, concurrent disorders, and health care utilization in homeless women

This study assessed lifetime and current prevalence rates of mental disorders and concurrent ment... more This study assessed lifetime and current prevalence rates of mental disorders and concurrent mental and substance use disorders in a sample of homeless women. Current suicide risk and recent health service utilization were also examined in order to understand the complex mental health issues of this population and to inform the development of new treatment strategies that better meet their specific needs. A cross-sectional survey of 196 adult homeless women in three different Canadian cities was done. Participants were assessed using DSM-IV-based structured clinical interviews. Current diagnoses were compared to available mental health prevalence rates in the Canadian female general population. Current prevalence rates were 63% for any mental disorder, excluding substance use disorders; 17% for depressive episode; 10% for manic episode; 7% for psychotic disorder; 39% for anxiety disorders, 28% for posttraumatic stress disorder; and 19% for obsessive-compulsive disorder; 58% had concurrent substance dependence and mental disorders. Lifetime prevalence rates were notably higher. Current moderate or high suicide risk was found in 22% of the women. Participants used a variety of health services, especially emergency rooms, general practitioners, and walk-in clinics. Prevalence rates of mental disorders among homeless participants were substantially higher than among women from the general Canadian population. The percentage of participants with moderate or high suicide risk and concurrent disorders indicates a high severity of mental health symptomatology. Treatment and housing programs need to be accompanied by multidisciplinary, specialized interventions that account for high rates of complex mental health conditions.

Research paper thumbnail of Smoking and Predictors of Nicotine Dependence in a Homeless Population

Nicotine & Tobacco …, Jan 1, 2011

To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and ... more To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and to investigate trends for demographic and clinical characteristics across different levels of nicotine dependence (nonsmokers vs. lowly dependent smokers vs. highly dependent smokers). A cross-sectional study of 489 homeless men and women in 3 Canadian cities. Each subject was assessed using structured clinical interviews and the Fagerström Test for Nicotine Dependence (FTND). Cochran-Armitage trend tests were applied to determine unadjusted trends in sociodemographic and clinical variables across levels of nicotine dependence. A generalized logit model was computed to adjust for potential confounding. The mean age was 37.9 years; 39.2% of the participants were women. About 80.8% were current smokers; the mean FTND score was 5.0. Although no significant differences were found between nonsmokers and smokers with low nicotine dependence, smokers with high nicotine dependence were only half as likely as nonsmokers to be Aboriginal, were 2.39 times more likely to have ever been incarcerated, and 2.44 times more likely to have current drug dependence. There were significant trends for the use of cocaine, opioids, and alcohol, with nonsmokers having the lowest and highly dependent smokers having the highest rates of using these substances. Available public health smoking cessation treatment opportunities should be made available within health care services for the homeless. There is also a need for developing and implementing tobacco dependence treatment programs, which are accessible and tailored to meet the needs of this specific population, accounting for polysubstance use and concurrent substance dependence and mental health disorders.

Research paper thumbnail of Is impulsivity in remitted bipolar disorder a stable trait? A meta-analytic review

Comprehensive psychiatry, 2014

To review scores on measures of impulsivity in remitted bipolar disorder. We used keywords "... more To review scores on measures of impulsivity in remitted bipolar disorder. We used keywords "impulsivity and bipolar" and "impulsivity and mania" to narrow down our search on Medline, EMBASE and Psychinfo to include those studies that had reported impulsivity scores using validated and reliable assessment measures in remitted bipolar disorder (both I and II). We searched all English language studies from 1990 to October 2012. Nineteen reports met the inclusion criteria and were reviewed by two abstractors independently. We generated weighted mean differences (WMDs) from pooled data using RevManager 5.0 from Cochrane analysis. The Barratt Impulsivity Scale (BIS) 11 was the instrument most commonly used. Nineteen studies met the inclusion criteria, of which 2 were excluded due to incomplete data. A WMD of 12.8 was observed for BIS 11 total scores, 4.3 on the motor component, 4.1 on the cognitive and 7.6 on the non-planning components of the BIS 11 respectively. Impu...

Research paper thumbnail of Stimulants and Cannabis Use Among a Marginalized Population in British Columbia, Canada: Role of Trauma and Incarceration

High rates of substance use, especially cannabis and stimulant use, have been associated with hom... more High rates of substance use, especially cannabis and stimulant use, have been associated with homelessness, exposure to trauma, and involvement with the criminal justice system. This study explored differences in substance use (cannabis vs. stimulants) and associations with trauma and incarceration among a homeless population. Data were derived from the BC Health of the Homeless Study (BCHOHS), carried out in three cities in British Columbia, Canada. Measures included sociodemographic information, the Maudsley Addiction Profile (MAP), the Childhood Trauma Questionnaire (CTQ), and the Mini International Neuropsychiatric Interview (MINI) Plus. Stimulant users were more likely to be female (43%), using multiple substances (3.2), and engaging in survival sex (14%). Cannabis users had higher rates of lifetime psychotic disorders (32%). Among the incarcerated, cannabis users had been subjected to greater emotional neglect (p < .05) and one in two cannabis users had a history of lifetime depressive disorders (p < .05). Childhood physical abuse and Caucasian ethnicity were also associated with greater crack cocaine use. One explanation for the results is that a history of childhood abuse may lead to a developmental cascade of depressive symptoms and other psychopathology, increasing the chances of cannabis dependence and the development of psychosis.

Research paper thumbnail of Annual Project Management Group Meeting

Research paper thumbnail of The Risk of Emergency Room Treatment Due to Overdose in Injection Drug Users

Journal of Addictive Diseases, 2009

This cohort study was conducted to identify risk factors for lifetime emergency room treatment du... more This cohort study was conducted to identify risk factors for lifetime emergency room treatment due to overdose in injection drug users. Data of 1049 patients on admission for opioid detoxification were analyzed. More than every third injection drug user (34.7%) experienced emergency room treatment due to an overdose. Using multiple logistic regression not living with a significant other drug user (odds ratio [OR] = 1.78, P = .002), history of suicide attempt (OR = 3.0, P = .000), daily use of barbiturates (OR = 2.17, P = .006) and cannabis (OR = 1.89, P = .001) were independently associated with emergency room treatment, whereas shorter duration of opioid use (OR = 0.23, P = .001) was independently associated with lack of emergency room treatment. Suicidal thoughts and multiple use of central nervous system depressants should be considered in injection drug users entering the emergency room due to an overdose. Emergency rooms should be seen as important places for offering further assistance (e.g., counselling) or referral to an addiction unit to drug users.

Research paper thumbnail of Homeless and incarcerated: An epidemiological study from Canada

International Journal of Social Psychiatry, 2014

Research paper thumbnail of The Opioid Peptides Enkephalin and β-Endorphin in Alcohol Dependence

Biological Psychiatry, 2008

Background-Experimental evidence indicates that the endogenous opioid system influences stress re... more Background-Experimental evidence indicates that the endogenous opioid system influences stress responses as well as reinforcing effects of addictive drugs. Because stress is an important factor contributing to drug dependence and relapse, we have now studied ethanol preference in enkephalin and β-endorphin deficient mice under baseline conditions and after stress exposure.

Research paper thumbnail of Impulsivity in remitted depression: A meta-analytical review

Asian Journal of Psychiatry, 2014

Research paper thumbnail of Mental disorder, service use, and barriers to care among 500 homeless people in 3 different urban settings

Social Psychiatry and Psychiatric Epidemiology, Jan 9, 2013

Research paper thumbnail of Columbia, Canada: Role of Trauma and Incarceration Stimulants and Cannabis Use Among a Marginalized Population in British

High rates of substance use, especially cannabis and stimulant use, have been associated with hom... more High rates of substance use, especially cannabis and stimulant use, have been associated with homelessness, exposure to trauma, and involvement with the criminal justice system. This study explored differences in substance use (cannabis vs. stimulants) and associations with trauma and incarceration among a homeless population. Data were derived from the BC Health of the Homeless Study (BCHOHS), carried out in three cities in British Columbia, Canada. Measures included sociodemographic information, the Maudsley Addiction Profile (MAP), the Childhood Trauma Questionnaire (CTQ), and the Mini International Neuropsychiatric Interview (MINI) Plus. Stimulant users were more likely to be female (43%), using multiple substances (3.2), and engaging in survival sex (14%). Cannabis users had higher rates of lifetime psychotic disorders (32%). Among the incarcerated, cannabis users had been subjected to greater emotional neglect ( p < .05) and one in two cannabis users had a history of lifeti...

Research paper thumbnail of Mental disorder, service use, and barriers to care among 500 homeless people in 3 different urban settings

Social Psychiatry and Psychiatric Epidemiology, 2013

Research paper thumbnail of Effects of Irritability on Craving before and after Cue Exposure in Abstinent Alcoholic Inpatients: Experimental Data on Subjective Response and Heart Rate

Neuropsychobiology, 2002

Objective: Irritability is often linked with problem drinking. The aim of this study is to examin... more Objective: Irritability is often linked with problem drinking. The aim of this study is to examine the possible influence of irritability on craving induced by a cue-exposure paradigm. Methods: 30 male abstinent alcoholic inpatients of the Psychiatric Hospital of Munich University, Germany gave answers to a series of personality questionnaires. Results of this study concerning the impact of aggressivity on craving for alcohol has recently been published. In this study, the subjects were subdivided into a low- and a high-irritable group based on their scores on the irritability subscale of the Buss-Durkee Hostility Inventory and were exposed to alcohol cues. Craving was measured by means of the Alcohol Craving Questionnaire (ACQ) and Visual Analogue Scales (VAS). The heart rate was also assessed throughout the whole process. ANCOVA for repeated measurement was employed to evaluate the data – irritability disposition as the between-subject factor and the experimental manipulation (abs...

Research paper thumbnail of Is exposure to childhood maltreatment associated with adult psychological distress among adult intravenous drug user?

Mental Health and Substance Use, 2013

Research paper thumbnail of Factors associated with exposure to hepatitis B virus in injection drug users

Drug and Alcohol Dependence, 2006

This study was undertaken to describe factors associated with exposure to the hepatitis B virus (... more This study was undertaken to describe factors associated with exposure to the hepatitis B virus (HBV) in treated injection drug users to better aim prevention and care in high risk subgroups. The naturalistic study was conducted in Munich, Germany, and 1018 patients who ever shared needles admitted for opioid detoxification were included. Sociodemographic, drug and drug treatment related variables and the virological status (HCV, HIV) were included in the bivariate and multiple logistic regression analysis. Sera were tested positive for antibodies against HBc in 40.2%, against HCV in 60.9%, and against HIV in 4.7% of patients. Older age, living without partner, longer duration of IDU, positive drug treatment history, imprisonment, emergency treatment, daily alcohol consumption, type of opioid dependency, and being positive for anti-HCV or anti-HIV were significant individual factors associated with positive anti-HBc-serology. Using multiple logistic regression history of imprisonment and being positive for anti-HCV remained independently associated with positive anti-HBc-serology. HBV-infection in IDUs should alert for simultaneous HCV-infection. Contacts to the criminal justice system are to be used for HBV prevention programs, including vaccination when indicated. Prevention programs should be implemented early in or even before the begin of a drug career.

Research paper thumbnail of The Association Between Childhood Maltreatment Subtypes and Current Suicide Risk Among Homeless Men and Women

Child Maltreatment, 2012

This study explored self-reports of five childhood maltreatment (CM) subtypes and their associati... more This study explored self-reports of five childhood maltreatment (CM) subtypes and their associations with current suicide risk in a sample of 500 homeless persons. Participants completed the Childhood Trauma Questionnaire and the Mini-International Neuropsychiatric Interview. Individual, unique, and cumulative associations of CM subtypes and subtype combinations with suicide risk (no vs. low vs. moderate/high) were examined. In multivariate analyses, four of the five CM subtypes were associated with suicide risk in individual models, but not in a model that included all CM subtypes. The strongest associations were found for reports of multitype CM involving all five subtypes. Mental disorders and female sex were independently associated with suicide risk. Clinicians working with CM victims should be aware that homeless clients are likely to report multitype maltreatment and should assess a variety of CM experiences. Future studies need to further examine multitype maltreatment and s...

Research paper thumbnail of Smoking and predictors of nicotine dependence in a homeless population

To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and ... more To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and to investigate trends for demographic and clinical characteristics across different levels of nicotine dependence (nonsmokers vs. lowly dependent smokers vs. highly dependent smokers). A cross-sectional study of 489 homeless men and women in 3 Canadian cities. Each subject was assessed using structured clinical interviews and the Fagerström Test for Nicotine Dependence (FTND). Cochran-Armitage trend tests were applied to determine unadjusted trends in sociodemographic and clinical variables across levels of nicotine dependence. A generalized logit model was computed to adjust for potential confounding. The mean age was 37.9 years; 39.2% of the participants were women. About 80.8% were current smokers; the mean FTND score was 5.0. Although no significant differences were found between nonsmokers and smokers with low nicotine dependence, smokers with high nicotine dependence were only half as likely as nonsmokers to be Aboriginal, were 2.39 times more likely to have ever been incarcerated, and 2.44 times more likely to have current drug dependence. There were significant trends for the use of cocaine, opioids, and alcohol, with nonsmokers having the lowest and highly dependent smokers having the highest rates of using these substances. Available public health smoking cessation treatment opportunities should be made available within health care services for the homeless. There is also a need for developing and implementing tobacco dependence treatment programs, which are accessible and tailored to meet the needs of this specific population, accounting for polysubstance use and concurrent substance dependence and mental health disorders.

Research paper thumbnail of M: The association between childhood maltreatment subtypes and current suicide risk amonghomeless men and women

This study explored self-reports of five childhood maltreatment (CM) subtypes and their associati... more This study explored self-reports of five childhood maltreatment (CM) subtypes and their associations with current suicide risk in a sample of 500 homeless persons. Participants completed the Childhood Trauma Questionnaire and the Mini-International Neuropsychiatric Interview. Individual, unique, and cumulative associations of CM subtypes and subtype combinations with suicide risk (no vs. low vs. moderate/high) were examined. In multivariate analyses, four of the five CM subtypes were associated with suicide risk in individual models, but not in a model that included all CM subtypes. The strongest associations were found for reports of multitype CM involving all five subtypes. Mental disorders and female sex were independently associated with suicide risk. Clinicians working with CM victims should be aware that homeless clients are likely to report multitype maltreatment and should assess a variety of CM experiences. Future studies need to further examine multitype maltreatment and s...

Research paper thumbnail of Mental disorders in ecstasy users: a prospective-longitudinal investigation

Drug and Alcohol Dependence, 2002

Objectives: To investigate the relationship between ecstasy use and mental disorders in a represe... more Objectives: To investigate the relationship between ecstasy use and mental disorders in a representative sample of adolescents and young adults. Method: Data for this investigation were drawn from the Early Developmental Stages of Psychopathology (EDSP) study, an epidemiological Á/longitudinal study in which 14 Á/24 year-olds were examined prospectively over a period of about 4 years. Results are based on N 0/2462 participants who completed the whole study period and for whom drug use behavior could be determined. Results: (1) Ecstasy users, compared with non-users, were at significantly increased risk of DSM-IV substance related disorders, including alcohol use disorders (52.6 vs. 15.6%; OR0/5.6, 95% CI 0/3.8 Á/8.1). Further, ecstasy users also had a higher risk of alcohol use disorders, when compared with users of other illicit substances (52.6 vs. 40.3%; OR 0/1.7, 95% CI 0/1.1 Á/2.4). (2) Ecstasy users had significantly higher rates for almost all DSM-IV mental disorders examined when compared with non-users (any non-substance use disorder: 68.7 vs. 44.5%; OR0/3.1, 95% CI0/2.1 Á/4.4) and compared with users of other illicit drugs (any non substance use disorder: 68.7 vs. 55.5%; OR 0/1.8, 95% CI 0/1.2 Á/2.6). (3) Ecstasy users also reported significantly higher rates of prescription medicine use, though they did not use more medical services than non-drug users. (4) Analyses of temporal patterns of ecstasy use and disorder onset revealed that the first use of ecstasy was secondary to the onset of DSM-IV mental disorders in the majority of cases. Still, subjects with mental disorders at baseline also showed a significantly increased risk for initiation of ecstasy use during the 4-year follow-up period. Conclusions: Care should be taken in cross sectional studies in interpreting mental disorder signs and symptoms merely as a consequence of ecstasy use, as ecstasy use might be associated with the use of multiple substances, and onset of mental disorder is more likely to precede rather than to follow use of ecstasy and related substances.

Research paper thumbnail of Role of Aggressivity on Reactivity and Craving before and after Cue Exposure in Recently Detoxified Alcoholics: Results from an Experimental Study

European Addiction Research, 2001

The role of aggressivity and cue exposure in induction of craving were investigated in a clinical... more The role of aggressivity and cue exposure in induction of craving were investigated in a clinical setting. Thirty abstinent alcoholic patients were divided into a low and a high aggressive group based on scores on the physical aggression subscale of the Buss-Durkee Hostility Inventory and exposed to alcohol cues. Craving was measured by means of the Alcohol Craving Questionnaire (ACQ) and Visual Analogue Scales (VAS). Important findings are: (1) main effects of aggressivity on ‘emotionality’, ‘purposefulness’ and ‘expectancy’ of ACQ were very significant; (2) on ‘drinking intention’ and ‘craving for alcohol’ of VAS, aggressivity and cue exposure showed a significant interaction; (3) the main effect of cue exposure on heart rate also reached a significance level of 0.007. The results were discussed in the context of the Classical, Operant Conditioning Theory, the Cognitive Craving Theory of Tiffany, Gilbert’s STAR Model, and the Self-Medication Hypothesis

Research paper thumbnail of Mental health, concurrent disorders, and health care utilization in homeless women

This study assessed lifetime and current prevalence rates of mental disorders and concurrent ment... more This study assessed lifetime and current prevalence rates of mental disorders and concurrent mental and substance use disorders in a sample of homeless women. Current suicide risk and recent health service utilization were also examined in order to understand the complex mental health issues of this population and to inform the development of new treatment strategies that better meet their specific needs. A cross-sectional survey of 196 adult homeless women in three different Canadian cities was done. Participants were assessed using DSM-IV-based structured clinical interviews. Current diagnoses were compared to available mental health prevalence rates in the Canadian female general population. Current prevalence rates were 63% for any mental disorder, excluding substance use disorders; 17% for depressive episode; 10% for manic episode; 7% for psychotic disorder; 39% for anxiety disorders, 28% for posttraumatic stress disorder; and 19% for obsessive-compulsive disorder; 58% had concurrent substance dependence and mental disorders. Lifetime prevalence rates were notably higher. Current moderate or high suicide risk was found in 22% of the women. Participants used a variety of health services, especially emergency rooms, general practitioners, and walk-in clinics. Prevalence rates of mental disorders among homeless participants were substantially higher than among women from the general Canadian population. The percentage of participants with moderate or high suicide risk and concurrent disorders indicates a high severity of mental health symptomatology. Treatment and housing programs need to be accompanied by multidisciplinary, specialized interventions that account for high rates of complex mental health conditions.

Research paper thumbnail of Smoking and Predictors of Nicotine Dependence in a Homeless Population

Nicotine & Tobacco …, Jan 1, 2011

To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and ... more To assess prevalence rates of tobacco use and dependence in a sample of homeless individuals and to investigate trends for demographic and clinical characteristics across different levels of nicotine dependence (nonsmokers vs. lowly dependent smokers vs. highly dependent smokers). A cross-sectional study of 489 homeless men and women in 3 Canadian cities. Each subject was assessed using structured clinical interviews and the Fagerström Test for Nicotine Dependence (FTND). Cochran-Armitage trend tests were applied to determine unadjusted trends in sociodemographic and clinical variables across levels of nicotine dependence. A generalized logit model was computed to adjust for potential confounding. The mean age was 37.9 years; 39.2% of the participants were women. About 80.8% were current smokers; the mean FTND score was 5.0. Although no significant differences were found between nonsmokers and smokers with low nicotine dependence, smokers with high nicotine dependence were only half as likely as nonsmokers to be Aboriginal, were 2.39 times more likely to have ever been incarcerated, and 2.44 times more likely to have current drug dependence. There were significant trends for the use of cocaine, opioids, and alcohol, with nonsmokers having the lowest and highly dependent smokers having the highest rates of using these substances. Available public health smoking cessation treatment opportunities should be made available within health care services for the homeless. There is also a need for developing and implementing tobacco dependence treatment programs, which are accessible and tailored to meet the needs of this specific population, accounting for polysubstance use and concurrent substance dependence and mental health disorders.

Research paper thumbnail of Is impulsivity in remitted bipolar disorder a stable trait? A meta-analytic review

Comprehensive psychiatry, 2014

To review scores on measures of impulsivity in remitted bipolar disorder. We used keywords "... more To review scores on measures of impulsivity in remitted bipolar disorder. We used keywords "impulsivity and bipolar" and "impulsivity and mania" to narrow down our search on Medline, EMBASE and Psychinfo to include those studies that had reported impulsivity scores using validated and reliable assessment measures in remitted bipolar disorder (both I and II). We searched all English language studies from 1990 to October 2012. Nineteen reports met the inclusion criteria and were reviewed by two abstractors independently. We generated weighted mean differences (WMDs) from pooled data using RevManager 5.0 from Cochrane analysis. The Barratt Impulsivity Scale (BIS) 11 was the instrument most commonly used. Nineteen studies met the inclusion criteria, of which 2 were excluded due to incomplete data. A WMD of 12.8 was observed for BIS 11 total scores, 4.3 on the motor component, 4.1 on the cognitive and 7.6 on the non-planning components of the BIS 11 respectively. Impu...

Research paper thumbnail of Stimulants and Cannabis Use Among a Marginalized Population in British Columbia, Canada: Role of Trauma and Incarceration

High rates of substance use, especially cannabis and stimulant use, have been associated with hom... more High rates of substance use, especially cannabis and stimulant use, have been associated with homelessness, exposure to trauma, and involvement with the criminal justice system. This study explored differences in substance use (cannabis vs. stimulants) and associations with trauma and incarceration among a homeless population. Data were derived from the BC Health of the Homeless Study (BCHOHS), carried out in three cities in British Columbia, Canada. Measures included sociodemographic information, the Maudsley Addiction Profile (MAP), the Childhood Trauma Questionnaire (CTQ), and the Mini International Neuropsychiatric Interview (MINI) Plus. Stimulant users were more likely to be female (43%), using multiple substances (3.2), and engaging in survival sex (14%). Cannabis users had higher rates of lifetime psychotic disorders (32%). Among the incarcerated, cannabis users had been subjected to greater emotional neglect (p < .05) and one in two cannabis users had a history of lifetime depressive disorders (p < .05). Childhood physical abuse and Caucasian ethnicity were also associated with greater crack cocaine use. One explanation for the results is that a history of childhood abuse may lead to a developmental cascade of depressive symptoms and other psychopathology, increasing the chances of cannabis dependence and the development of psychosis.

Research paper thumbnail of Annual Project Management Group Meeting

Research paper thumbnail of The Risk of Emergency Room Treatment Due to Overdose in Injection Drug Users

Journal of Addictive Diseases, 2009

This cohort study was conducted to identify risk factors for lifetime emergency room treatment du... more This cohort study was conducted to identify risk factors for lifetime emergency room treatment due to overdose in injection drug users. Data of 1049 patients on admission for opioid detoxification were analyzed. More than every third injection drug user (34.7%) experienced emergency room treatment due to an overdose. Using multiple logistic regression not living with a significant other drug user (odds ratio [OR] = 1.78, P = .002), history of suicide attempt (OR = 3.0, P = .000), daily use of barbiturates (OR = 2.17, P = .006) and cannabis (OR = 1.89, P = .001) were independently associated with emergency room treatment, whereas shorter duration of opioid use (OR = 0.23, P = .001) was independently associated with lack of emergency room treatment. Suicidal thoughts and multiple use of central nervous system depressants should be considered in injection drug users entering the emergency room due to an overdose. Emergency rooms should be seen as important places for offering further assistance (e.g., counselling) or referral to an addiction unit to drug users.

Research paper thumbnail of Homeless and incarcerated: An epidemiological study from Canada

International Journal of Social Psychiatry, 2014

Research paper thumbnail of The Opioid Peptides Enkephalin and β-Endorphin in Alcohol Dependence

Biological Psychiatry, 2008

Background-Experimental evidence indicates that the endogenous opioid system influences stress re... more Background-Experimental evidence indicates that the endogenous opioid system influences stress responses as well as reinforcing effects of addictive drugs. Because stress is an important factor contributing to drug dependence and relapse, we have now studied ethanol preference in enkephalin and β-endorphin deficient mice under baseline conditions and after stress exposure.

Research paper thumbnail of Impulsivity in remitted depression: A meta-analytical review

Asian Journal of Psychiatry, 2014