Nicotine dependence in schizophrenia: clinical phenomena and laboratory findings

Relationship between functional connectivity and weight-gain risk of antipsychotics in schizophrenia

BACKGROUND

The mechanisms by which antipsychotic medications (APs) contribute to obesity in schizophrenia are not well understood. Because AP effects on functional brain connectivity may contribute to weight effects, the current study investigated how AP-associated weight-gain risk relates to functional connectivity in schizophrenia.

METHODS

Fifty-five individuals with schizophrenia (final N = 54) were divided into groups based on previously reported AP weight-gain risk (no APs/low risk [N = 19]; moderate risk [N = 17]; high risk [N = 18]). Resting-state functional magnetic resonance imaging (fMRI) was completed after an overnight fast ("fasted") and post-meal ("fed"). Correlations between AP weight-gain risk and functional connectivity were assessed at the whole-brain level and in reward- and eating-related brain regions (anterior insula, caudate, nucleus accumbens).

RESULTS

When fasted, greater AP weight-gain risk was associated with increased connectivity between thalamus and sensorimotor cortex (pFDR = 0.021). When fed, greater AP weight-gain risk was associated with increased connectivity between left caudate and left precentral/postcentral gyri (pFDR = 0.048) and between right caudate and multiple regions, including the left precentral/postcentral gyri (pFDR = 0.001), intracalcarine/precuneal/cuneal cortices (pFDR < 0.001), and fusiform gyrus (pFDR = 0.008). When fed, greater AP weight-gain risk was also associated with decreased connectivity between right anterior insula and ventromedial prefrontal cortex (pFDR = 0.002).

CONCLUSIONS

APs with higher weight-gain risk were associated with greater connectivity between reward-related regions and sensorimotor regions when fasted, perhaps relating to motor anticipation for consumption. Higher weight-gain risk APs were also associated with increased connectivity between reward, salience, and visual regions when fed, potentially reflecting greater desire for consumption following satiety.

The Prenatal Hypoxic Pathology Associated with Maternal Stress Predisposes to Dysregulated Expression of the chrna7 Gene and the Subsequent Development of Nicotine Addiction in Adult Offspring

INTRODUCTION

Previous studies have shown that fetal hypoxia predisposes individuals to develop addictive disorders in adulthood. However, the specific impact of maternal stress, mediated through glucocorticoids and often coexisting with fetal hypoxia, is not yet fully comprehended.

METHODS

To delineate the potential effects of these pathological factors, we designed models of prenatal severe hypoxia (PSH) in conjunction with maternal stress and prenatal intrauterine ischemia (PII). We assessed the suitability of these models for our research objectives by measuring HIF1α levels and evaluating the glucocorticoid neuroendocrine system. To ascertain nicotine dependence, we employed the conditioned place aversion test and the startle response test. To identify the key factor implicated in nicotine addiction associated with PSH, we employed techniques such as Western blot, immunohistochemistry, and correlational analysis between chrna7 and nr3c1 genes across different brain structures.

RESULTS

In adult rats exposed to PSH and PII, we observed increased levels of HIF1α in the hippocampus (HPC). However, the PSH group alone exhibited reduced glucocorticoid receptor levels and disturbed circadian glucocorticoid rhythms. Additionally, they displayed signs of nicotine addiction in the conditioned place aversion and startle response tests. We also observed elevated levels of phosphorylated DARPP-32 protein in the nucleus accumbens (NAc) indicated compromised glutamatergic efferent signaling. Furthermore, there was reduced expression of α7 nAChR, which modulates glutamate release, in the medial prefrontal cortex (PFC) and HPC. Correlation analysis revealed strong associations between chrna7 and nr3c1 expression in both brain structures.

CONCLUSION

Perturbations in the glucocorticoid neuroendocrine system and glucocorticoid-dependent gene expression of chrna7 associated with maternal stress response to hypoxia in prenatal period favor the development of nicotine addiction in adulthood.

An Exploration of Smoking Patterns Among People with Serious Mental Illness Attending an Outpatient Clinic in Qatar

BACKGROUND

Studies have shown that tobacco use is exceptionally high in people affected with serious mental illness (SMI). Many countries worldwide have observed a decrease in the prevalence of tobacco smoking; however, the smoking rates among people with SMI have declined much less than in those without mental illness. To date, no nationally representative data have examined the smoking patterns or the sociocultural factors that influence smoking among SMI people in Qatar.

METHODS

A retrospective medical chart review was conducted to collect patient demographics, psychiatric and medical comorbidities, medications, the most recently documented smoking status and if on tobacco cessation treatment. A descriptive and inferential analysis of the data was performed.

RESULTS

Of 346 patients included in the cohort, 196 (56.6%) had their smoking status documented, of which 72 (36.7%) were "currently smoking." Significantly more males than females were "current smokers" (62.9% versus 15.0%, respectively, p < 0.001). Significantly more patients with psychotic disorders than those with any other SMI were "current smokers", and this difference was statistically significant (p = 0.006). Positive and significant associations with current smoking were found for the male gender, psychotic disorders, and high levels (≥6.2 mmol/L) of total cholesterol. Only 12 (16.7%) of current smokers were receiving smoking cessation treatment.

CONCLUSION

More than half of a sample of people with SMI attending outpatient psychiatric services in Qatar had documented smoking status. Still, only a few current smokers were on smoking cessation treatment. Efforts are needed to implement smoking cessation strategies in this population.

Transgenerational evidence of increases in dopamine D2 receptor sensitivity in rodents: Impact on sensorimotor gating, the behavioral response to nicotine and BDNF

BACKGROUND/AIMS

Neonatal quinpirole (NQ) treatment to rats increases dopamine D₂ (DAD₂) receptor sensitivity in adult animals. We investigated if increased DAD₂ sensitivity would be passed to the next (F1) generation, and if these animals demonstrated sensorimotor gating deficits and enhanced behavioral responses to nicotine.

METHODS

Male and female rats were intraperitoneal (IP) administered quinpirole (1 mg/kg) or saline (NS) from postnatal day (P)1-21. Animals were either behaviorally tested (F0) or raised to P60 and mated, creating F1 offspring.

RESULTS

Experiment 1 revealed that F1 generation animals that were the offspring of at least one NQ-treated founder increased yawning behavior, a DAD₂-mediated behavioral event, in response to acute quinpirole (0.1 mg/kg). F1 generation rats also demonstrated increased striatal β arrestin-2 and decreased phospho-AKT signaling, consistent with increased G-protein independent DAD₂ signaling, which was equal to F0 NQ-treated founders, although this was not observed in all groups. RNA-Seq analysis revealed significant gene expression changes in the F1 generation that were offspring of both NQ-treated founders compared to F0 NQ founders and controls, with enrichment in sensitivity to stress hormones and cell signaling pathways. In Experiment 2, all F1 generation offspring demonstrated sensorimotor gating deficits compared to controls, which were equivalent to F0 NQ-treated founders. In Experiment 3, all F1 generation animals demonstrated enhanced nicotine behavioral sensitization and nucleus accumbens (NAcc) brain-derived neurotrophic factor (BDNF) protein. Further, F1 generation rats demonstrated enhanced adolescent nicotine conditioned place preference equivalent to NQ-treated founders conditioned with nicotine.

CONCLUSIONS

This represents the first demonstration of transgenerational effects of increased DAD₂ sensitivity in a rodent model.

Smoking Affects the Patterns of Metabolic Disorders and Metabolic Syndrome in Patients With First-Episode Drug-Naive Schizophrenia: A Large Sample Study Based on the Chinese Han Population

OBJECTIVE

Although metabolic disorders and smoking are common in schizophrenia, few studies have investigated the effects of smoking on metabolic disorders or metabolic syndrome (MetS) in schizophrenia patients, especially in first-episode drug-naïve (FEDN) patients. We sought to investigate the differences in metabolic disorders and MetS between smoking and nonsmoking FEDN schizophrenia patients.

METHODS

A total of 428 FEDN schizophrenia patients and 435 controls were recruited. Blood pressure, waist circumference, body mass index (BMI), lipid profiles, and glucose metabolism were measured. The psychopathology was evaluated by Positive and Negative Syndrome Scale.

RESULTS

FEDN schizophrenia patients had a higher smoking rate than controls (23.8% vs 14.0%, P < .001). After adjusting for confounding variables, the prevalence of MetS, overweight, hypertension, hypertriglyceridemia, elevated insulin, and insulin resistance in smoking patients was higher than those in nonsmoking patients, while overweight and hypertension were higher in the smoking controls than in nonsmoking controls (all P < .05). In smoking patients, triglyceridemia, high-density lipoprotein cholesterol, and fasting blood glucose were the main contributing components to MetS, while in nonsmoking patients, waist circumference, systolic blood pressure, triglyceridemia, high-density lipoprotein cholesterol, and fasting blood glucose were the main contributing components to MetS. In smoking patients, BMI and homeostatic model assessment for insulin resistance were associated factors of MetS (both P < .05). In nonsmoking patients, sex, BMI, insulin, and homeostatic model assessment for insulin resistance were associated factors of MetS (all P < .05).

CONCLUSIONS

Our study indicates that smoking schizophrenia patients have a higher prevalence of MetS and metabolic disorders than nonsmoking patients. Moreover, smoking and nonsmoking patients have different contributing components and associated factors for MetS.

Cigarette smoking and schizophrenia: Mendelian randomisation study

BACKGROUND

The link between schizophrenia and cigarette smoking has been well established through observational studies. However, the cause-effect relationship remains unclear.

AIMS

We conducted Mendelian randomisation analyses to assess any causal relationship between genetic variants related to four smoking-related traits and the risk of schizophrenia.

METHOD

We performed a two-sample Mendelian randomisation using summary statistics from genome-wide association studies (GWAS) of smoking-related traits and schizophrenia (7711 cases, 18 327 controls) in East Asian populations. Single nucleotide polymorphisms (SNPs) correlated with smoking behaviours (smoking initiation, smoking cessation, age at smoking initiation and quantity of smoking) were investigated in relation to schizophrenia using the inverse-variance weighted (IVW) method. Further sensitivity analyses, including Mendelian randomisation-Egger (MR-Egger), weighted median estimates and leave-one-out analysis, were used to test the consistency of the results.

RESULTS

The associated SNPs for the four smoking behaviours were not significantly associated with schizophrenia status. Pleiotropy did not inappropriately affect the results.

CONCLUSIONS

Cigarette smoking is a complex behaviour in people with schizophrenia. Understanding factors underlying the observed association remains important; however, our findings do not support a causal role of smoking in influencing risk of schizophrenia.

The association between demographic characteristics, personality, and mental health of bus drivers in China: A structural equation model

BACKGROUND

The psychological status of drivers is related to adverse driving behaviors. Although there are several studies on the mental health and traffic accidents among bus drivers, related studies on the association between mental health and individual characteristics are scarce.

METHODS

Our report is on a cross-sectional study of bus drivers that took place between October 2014 and May 2016. A total of 596 bus drivers who worked for transportation companies and underwent occupational physical examinations at The Guangxi Zhuang Autonomous Region workers' Hospital during the study period were included. Demographic characteristics were collected by a self-designed demographic questionnaire. The Eysenck Personality Questionnaire (EPQ) and the Symptom Checklist 90-Revised (SCL-90-R) were used to evaluate the personality and mental health of bus drivers, and the results of the scales were compared with Chinese norms. The structural equation model was used to analyze the correlation among demographic characteristics, personality characteristics, and mental health.

RESULTS

Except for the lie dimension, the average scores of the driver's personality dimension were higher than the Chinese norm, and the means of somatization and phobia scores of bus drivers were also higher; obsessions-compulsions, interpersonal sensitivity, and depression scores were lower than those for the Chinese norms. The structural equations modeling revealed that the total effects coefficient of demographic characteristics on mental health was 0.68, and that of personality was 0.60. There were direct influences between demographic characteristics and personality characteristics, demographic characteristics and mental health, and personality characteristics and mental health; the standardized path coefficients were 0.60, 0.50, and 0.30, respectively. Smoking, drinking, and neuroticism were the main factors affecting the mental health of bus drivers; and the standardized path coefficients were 0.56, 0.54, and 0.90 respectively.

CONCLUSIONS

In this study, bus drivers were significantly more extroverted, psychotic, and neurotic than the general population; and they were more likely to suffer from somatization and phobia. The mental health of bus drivers was associated with some demographic and personality characteristics in the study. These findings provide a theoretical basis for the selection of bus drivers and intervention measures for drivers with high-risk driving tendencies, which is conducive to better guide road traffic safety construction and reduce the occurrence of road traffic injuries.

Cigarette Smoking and Schizophrenia: Etiology, Clinical, Pharmacological, and Treatment Implications

Recent data suggests that the prevalence of smoking in schizophrenia remains high. While reports suggest that smoking increases the risk of developing schizophrenia, the potential causative role of smoking in this relationship needs further investigation. Smokers with schizophrenia are more likely to have more intense positive symptoms and lower cognitive function, but diminished intensity of extrapyramidal side effects than nonsmoking patients with schizophrenia. They were also more likely to exhibit aggressive behaviour compared to nonsmokers, which could suggest higher levels of baseline aggression. The significant cost associated with regular tobacco expenditure can detract from investment in key domains. Large-scale trials have shown that pharmacotherapy for smoking cessation is effective and does not worsen the risk of developing neuropsychiatric symptoms compared to placebo. Electronic cigarette use among schizophrenia patients is high, and there is emerging evidence supportive of its efficacy. Future improvements include large-scale trials assessing the utility, efficacy, and safety of electronic cigarettes in schizophrenia patients.

The risk of physical multimorbidity in people with psychotic disorders: A systematic review and meta-analysis

BACKGROUND

The occurrence of multiple co-occurring chronic health conditions, known as multimorbidity, is associated with decreases in quality of life for patients and poses unique challenges for healthcare systems. Since people with psychotic disorders have an excess of physical health conditions compared to the general population, they may also be at a higher risk for multimorbidity. We conducted a systematic review and meta-analysis to quantify the prevalence and excess risk of multimorbidity among people with psychotic disorders, relative to those without psychosis.

METHODS

We searched the MEDLINE, EMBASE, and PsycINFO databases, and conducted forward and backward citation tracing of included studies. Studies published after 1990 were included if they reported the prevalence of multiple chronic physical health conditions among people with psychotic disorders. Data on the prevalence and relative risk of multimorbidity were meta-analyzed using random effects models.

RESULTS

Fourteen studies met the inclusion criteria, and eight were included in the meta-analysis. Each study used a different operational definition of multimorbidity, both for the number and types of chronic conditions, which resulted in a wide range in prevalence estimates (16% to 91%). People with psychotic disorders had an increased risk of multimorbidity (RR = 1.69, 95%CI = 1.37,2.08), relative to those without psychosis.

CONCLUSIONS

People with psychotic disorders are more likely to experience multimorbidity than those without psychotic disorders. Clinicians treating people with psychosis should closely monitor for a range of physical health conditions. Future research examining multimorbidity among people with psychiatric illness should employ consistent definitions to better enable cross-study comparisons.

Genetic Determinants of Gating Functions: Do We Get Closer to Understanding Schizophrenia Etiopathogenesis?

Deficits in the gating of sensory stimuli, i.e., the ability to suppress the processing of irrelevant sensory input, are considered to play an important role in the pathogenesis of several neuropsychiatric disorders, in particular schizophrenia. Gating is disrupted both in schizophrenia patients and their unaffected relatives, suggesting that gating deficit may represent a biomarker associated with a genetic liability to the disorder. To assess the strength of the evidence for the etiopathogenetic links between genetic variation, gating efficiency, and schizophrenia, we carried out a systematic review of human genetic association studies of sensory gating (suppression of the P50 component of the auditory event-related brain potential) and sensorimotor gating (prepulse inhibition of the acoustic startle response). Sixty-three full-text articles met the eligibility criteria for inclusion in the review. In total, 117 genetic variants were reported to be associated with gating functions: 33 variants for sensory gating, 80 variants for sensorimotor gating, and four variants for both sensory and sensorimotor gating. However, only five of these associations (four for prepulse inhibition-CHRNA3 rs1317286, COMT rs4680, HTR2A rs6311, and TCF4 rs9960767, and one for P50 suppression-CHRNA7 rs67158670) were consistently replicated in independent samples. Although these variants and genes were all implicated in schizophrenia in research studies, only two polymorphisms (HTR2A rs6311 and TCF4 rs9960767) were also reported to be associated with schizophrenia at a meta-analytic or genome-wide level of evidence. Thus, although gating is widely considered as an important endophenotype of schizophrenia, these findings demonstrate that evidence for a common genetic etiology of impaired gating functions and schizophrenia is yet unsatisfactory, warranting further studies in this field.

Negative affect among daily smokers: A systematic review and meta-analysis

BACKGROUND

Negative Affect (NA), as a personality trait is a tendency towards experiencing a more negative emotion. The body of research suggests that NA encourages smoking relapse and smoking as a reason for NA reduction, though. The likelihood of this connection does not seem to be bright yet. The present study critically reviews researches to synthesize the existing literature to determine the strength of this linkage.

METHODS

Key-word related research was systematically searched in PubMed, PsychINFO, Science Direct and Google Scholar for studies conducted from 1980 to 2019, followed by, the assessment and selection of retrieved studies based on defined inclusion criteria. A random-effects meta-analysis model was used to examine the prospective relationship between NA and smoking. Meta-regression was also used to dig for possible explanations of heterogeneity. Furthermore a multi-moderators model and sub-group analyses examined the moderating factors.

RESULTS

Forty effect-sizes comprising 12 cross-sectional studies, 28 longitudinal studies and 24,913 participants were included in the meta-analysis. The forest plot of the pooled correlation effect size in the random model indicates a significant effect size of the relationship between NA and smoking (r = 0.11; 95%CI 0.071-0.15, P = 0.001) in the meta-analysis with high heterogeneity (Q = 473.916; df=39; P = 0.001; I²=91.77%). Also, the pooled effect size was obtained as 0.143 (95%CI 0.071-0.214) for light-to-moderate and 0.112 (95%CI 0.057-0.166) for moderate-to-heavy smokers, with the effect size ranging from 0.061 to 0.195 which was significant among all subtypes, though this trend seem higher among adolescents, males, and longitudinal studies than in adults, females, and cross-sectional studies.

LIMITATIONS

The review was limited to English articles, and the heterogeneity of the studies were high.

CONCLUSION

These results support the notion that NA was positively and weakly linked to smoking and this linkage is stronger in light-to-moderate smokers, males, and adolescents. Theoretical and clinical implications are discussed with the aim of extending future directions on NA and smoking.

Effects of Smoking Status on Remission and Metabolic and Cognitive Outcomes in Schizophrenia Patients Treated with Clozapine

BACKGROUND

Even though clozapine is the recommended last-resort antipsychotic, many patients fail to respond and show treatment-refractory psychotic symptoms. Smoking has been suggested as a possible risk factor for poor clozapine response, hampering remission and negatively impacting somatic outcomes.

METHODS

Our aim was to test whether smoking status is associated with remission rates and other symptomatic and somatic outcomes. We therefore assessed remission rates according to The Remission in Schizophrenia Working Group (RSWG) criteria, and metabolic and cognitive outcomes among patients with schizophrenia-spectrum disorders treated with clozapine for at least 6 months. For analyses, we grouped our cohort into 3 groups according to clozapine treatment duration (6 months, 2 years, 5 years).

RESULTS

One hundred five patients were included in our analyses and grouped according to their clozapine treatment duration. In the 6-months analyses, patients who smoked were significantly more likely to be younger of age (p=0.002) despite on average shorter duration of clozapine treatment (p=0.041) and significantly more likely to be treated with mood-stabilizing co-medication (p=0.030) compared to nonsmokers. Remission rates (p=0.490), as well as a set of metabolic and cognitive variables did not differ between the 2 groups. A related pattern could be observed for the 2- and 5-years analyses.

CONCLUSIONS

Smoking behavior among clozapine-treated schizophrenia patients might delineate a cohort with an earlier onset of the disease. Nevertheless, most findings comparing disease-specific and clinical outcomes among smokers and nonsmokers were negative. Further research is needed to identify strategies to overcome insufficient remission rates in this patient group.

Increased dopamine availability magnifies nicotine effects on cognitive control: A pilot study

INTRODUCTION AND OBJECTIVES

The ability to adapt to new task demands flexibly and to stabilise performance in the presence of distractors is termed cognitive control and is mediated by dopaminergic and cholinergic neurotransmission. We aimed to test the hypothesis that the effect of the cholinergic agonist nicotine on cognitive control depends on baseline dopamine levels.

METHODS

Thirty-eight healthy non-smokers (16 males; M_age=24.05 years) performed a cognitive control task including distractor and switch trials twice. Subjects were split into two parallel groups. One group received 2 g of L-tyrosine two hours prior to testing to manipulate dopamine availability experimentally, while the other group received placebo on both days. One hour later, both groups received in a within-subject design: on one day, a 7 mg nicotine patch; on the other day, a matched placebo. Response time costs for distractor and switch trials served as measures of cognitive stability and flexibility.

RESULTS

Nicotinic modulation reduced response time costs in switch trials and increased costs in distractor trials (nicotine×condition, p=0.027) with a trend-wise interaction between nicotine, L-tyrosine and trial type (nicotine×L-tyrosine×condition, p=0.068), which was due to stronger nicotine effects under L-tyrosine.

CONCLUSIONS

Our data provide preliminary evidence that nicotine has opponent effects on cognitive stability and flexibility. Subjects who received the dopamine precursor L-tyrosine were more prone to nicotine effects on behaviours, which are improvements in cognitive flexibility at the cost of decreased cognitive stability.

Targeted Intervention to Reduce Smoking among People with Severe Mental Illness: Implementation of a Smoking Cessation Intervention in an Inpatient Mental Health Setting

Background and Objectives: Smoking and smoking-related harms are highly prevalent among people with severe mental illness. Targeted smoking cessation programs are much needed in this population. This pilot study aimed to assess the effectiveness of implementing smoking cessation system change interventions within an acute inpatient mental health unit. Materials and Methods: Design: Pre-post intervention study. System change interventions for smoking cessation were delivered over a three-month period (05 March 2018-04 June 2018) on an acute inpatient mental health unit. Participants (n = 214) were all individuals receiving care as inpatients during the three-month intervention. Outcomes assessed pre- and post-intervention were: (i) recording of patient smoking status in medical notes, (ii) number of inpatients offered smoking cessation medication, and iii) number of violent incidents reported. Results: Recording of smoking status significantly increased from 1.9% to 11.4% (X² = 14.80; p ≤ 0.001). The proportion of inpatients offered smoking cessation treatment significantly increased from 11.0% to 26.8% (X² = 16.01; p ≤ 0.001). The number of violent incidents decreased by half, which was not statistically significant. Conclusion: Evidence-based smoking cessation interventions can be successfully implemented on an inpatient mental health unit. Modest gains were made in routine screening for smoking and in smoking cessation treatment prescription. Future studies should prioritize effective participatory collaboration with staff to optimize effectiveness of interventions and should include additional strategies such as brief intervention training and smoking cessation treatments such as varenicline and buproprion in addition to nicotine replacement therapy (NRT).

Identification of 34 genes conferring genetic and pharmacological risk for the comorbidity of schizophrenia and smoking behaviors

The prevalence of smoking is significantly higher in persons with schizophrenia (SCZ) than in the general population. However, the biological mechanisms of the comorbidity of smoking and SCZ are largely unknown. This study aimed to reveal shared biological pathways for the two diseases by analyzing data from two genome-wide association studies with a total sample size of 153,898. With pathway-based analysis, we first discovered 18 significantly enriched pathways shared by SCZ and smoking, which were classified into five groups: postsynaptic density, cadherin binding, dendritic spine, long-term depression, and axon guidance. Then, by using an integrative analysis of genetic, epigenetic, and expression data, we found not only 34 critical genes (e.g., PRKCZ, ARHGEF3, and CDKN1A) but also various risk-associated SNPs in these genes, which convey susceptibility to the comorbidity of the two disorders. Finally, using both in vivo and in vitro data, we demonstrated that the expression profiles of the 34 genes were significantly altered by multiple psychotropic drugs. Together, this multi-omics study not only reveals target genes for new drugs to treat SCZ but also reveals new insights into the shared genetic vulnerabilities of SCZ and smoking behaviors.

Schizophrenia and pregnancy: a national register-based follow-up study among Finnish women born between 1965 and 1980

To assess psychosocial and somatic risk factors related to pregnancy, and pregnancy-related complications or disorders in women with schizophrenia compared to population controls. In this register-based cohort study, we identified all Finnish women who were born in 1965-1980 and diagnosed with schizophrenia in psychiatric care before 31 December 2013. For each case, five age- and place-of-birth matched controls were randomly selected. They were followed from the day when the disorder was diagnosed in specialized health care till the end of 2013. The mean follow-up time was 14.0 + 6.91 vs. 14.3 + 6.89 years. Altogether, 1162 singleton pregnancies were found among affected women and 4683 among controls. Affected women were significantly older and more often single; their body mass index before pregnancy was significantly higher, and they smoked significantly more often both in the beginning of pregnancy and after the first trimester than controls. They showed a significantly higher odds for pathologic oral glucose tolerance test (odds ratio (OR) 1.66, 95% confidence interval (95% CI) 1.27-2.17), initiation of insulin treatment (OR 1.84, 95% CI 1.15-2.93), fast fetal growth (OR 1.62, 95% CI 1.03-2.52), premature contractions (OR 2.42, 95% CI 1.31-4.49), hypertension (OR 1.81, 95% CI 1.01-3.27), and pregnancy-related hospitalizations (OR 1.97, 95% CI 1.66-2.33). Suspected damage to the fetus from alcohol/drugs was significantly more common among affected women than controls. Women with schizophrenia have higher prevalence of psychosocial and somatic risk factors related to pregnancy, as well as pregnancy-related complications and disorders than non-affected women.

A retrospective cohort study of the prevalence of anxiety and agitation in schizophrenic smokers and the unmet needs of smoking cessation programs

Achieving abstinence in schizophrenic smokers using a combination of medications and cognitive behavioral therapy is feasible; however, abstinence rates are significantly lower compared to the general population and studies are scanty. Additionally, maintaining sustained abstinence and preventing relapse is a major limiting factor and represents key tasks in managing tobacco dependence in schizophrenic patients. Several theories have been postulated to explain the higher tendency of tobacco use among schizophrenic individuals. Schizophrenic patients may use nicotine as a "self-medication" strategy to improve negative symptoms of schizophrenia. However, studies suggest that although nicotine may act as an anxiolytic acutely, chronic use of nicotine may lead to increased anxiety with the possibility of increased catecholamines, which is confirmed with the prevalence of tachycardia and hypertension in smokers in general. On this basis, the main objective of our present study was to assess anxiety in schizophrenic smoking and nonsmoking patients by comparing the number of anxiety and agitation episodes and evaluating the amount of antianxiety/antiagitation medication used by each group. A separate objective was to document the unmet needs of smoking cessation programs in treating schizophrenic patients. Consequently, in the present retrospective cohort study, it was observed that schizophrenic smokers tend to have higher anxiety episodes and utilize as-needed medications at a higher frequency compared to nonsmokers for the relief of anxiety and agitation symptoms. Further research is warranted to examine these results on a larger scale.

Coping Strategies for Oral Health Problems by People with Schizophrenia

BACKGROUND

Persons with schizophrenia are particularity susceptible to poor oral health. Symptoms of schizophrenia often affect oral health behaviors and lifestyle. The aim was to explore coping strategies used by people with schizophrenia in oral health in order to understand and to best involve them in the management of their own oral health in daily life.

MATERIALS AND METHODS

This is systematic review reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statements. We included cross-sectional and longitudinal quantitative and qualitative studies that 1) examined coping strategies regarding oral health in persons with schizophrenia or 2) examined coping strategies were used in dental care. We included studies conducted with at least one PWS aged 18 years old more and without restriction on sex, socioeconomic status, or language.

RESULTS

The 8 studies included suggest that coping strategies depends on complex translation processes that can be either personal (e.g., psychological symptomatology, neuropsychological functioning to adversely affect hope, self-esteem, self-stigma, self-determination, sense of coherence, and resilience) and/or environmental factors (e.g., peer support and efficacy of rehabilitations programs). We further identified that the main factor influencing coping strategies was dental stress situation.

CONCLUSIONS

This review suggests that coping strategies play a crucial role in the recovery process for oral health of PWS. Translation processes in oral health should be more explored in the future to clarify the capacity of PWS to cope with essential self-care in oral health on daily life.

A Genetic Model of Impulsivity, Vulnerability to Drug Abuse and Schizophrenia-Relevant Symptoms With Translational Potential: The Roman High- vs. Low-Avoidance Rats

The bidirectional selective breeding of Roman high- (RHA) and low-avoidance (RLA) rats for respectively rapid vs. poor acquisition of active avoidant behavior has generated two lines/strains that differ markedly in terms of emotional reactivity, with RHA rats being less fearful than their RLA counterparts. Many other behavioral traits have been segregated along the selection procedure; thus, compared with their RLA counterparts, RHA rats behave as proactive copers in the face of aversive conditions, display a robust sensation/novelty seeking (SNS) profile, and show high impulsivity and an innate preference for natural and drug rewards. Impulsivity is a multifaceted behavioral trait and is generally defined as a tendency to express actions that are poorly conceived, premature, highly risky or inappropriate to the situation, that frequently lead to unpleasant consequences. High levels of impulsivity are associated with several neuropsychiatric conditions including attention-deficit hyperactivity disorder, obsessive-compulsive disorder, schizophrenia, and drug addiction. Herein, we review the behavioral and neurochemical differences between RHA and RLA rats and survey evidence that RHA rats represent a valid genetic model, with face, construct, and predictive validity, to investigate the neural underpinnings of behavioral disinhibition, novelty seeking, impulsivity, vulnerability to drug addiction as well as deficits in attentional processes, cognitive impairments and other schizophrenia-relevant traits.

Tobacco smoking and schizophrenia: re-examining the evidence

Tobacco smoking among people with mental illnesses can be explained by biological, psychological and social factors. The prevalence of smoking in people diagnosed with schizophrenia is higher than in people with other mental disorders and in the general population. This article explores three current hypotheses that explain this higher prevalence of smoking in schizophrenia. The first, the self-medication hypothesis, is increasingly countered by a growing body of evidence indicating that smokers experience more severe symptoms of schizophrenia. Numerous researchers have already identified smoking as a possible risk factor for the development of schizophrenia, which is the second hypothesis. The third hypothesis (shared genetic vulnerability) identifies certain genes that confer vulnerability for both schizophrenia and nicotine dependence. Understanding the reasons behind the higher prevalence of smoking among people with schizophrenia is vital in planning effective primary, secondary and tertiary smoking prevention for these individuals.

LEARNING OBJECTIVES

At the end of this article, readers will be able to: •

Effects of Cigarette Smoking and Clozapine Treatment on 20-Year All-Cause & Cardiovascular Mortality in Schizophrenia

To estimate 20-year mortality risk in people with schizophrenia treated with second-generation antipsychotics (SGA) and examine the effects of cigarette smoking on mortality. Of the 1199 individuals with schizophrenia in the study, estimated 20-year all-cause mortality risk by Kaplan Meier Curve was 30% and leading causes of death included 27% cardiovascular disease, 13% cancer, 12% non-HIV infection, 5% respiratory causes, 20% other causes and 18% had unknown cause of death. For all-cause mortality, we found that white race and male sex were significant risk factors (HR = 1.5, p = 0.002 and HR = 1.33, p = 0.033, respectively). For cardiovascular mortality risk, we showed that cigarette smokers and white race were at higher risk (HR = 1.86, p = 0.017 and HR = 1.71, p = 0.045, respectively). Cardiovascular mortality risk at 20-years is 11%. Kaplan-Meier Survival Curve showed a statistical difference for smokers and non-smokers in cardiovascular mortality over the 20-year follow-up (Log rank chi-square = 5.35, df = 1, p = 0.02). 20-year all-cause mortality risk for individuals with schizophrenia was found to be 30% with cardiovascular disease as a leading cause. Cigarette smokers and white race were associated with an increased risk of death. Regarding cardiovascular mortality specifically, cigarette smoking increased risk by 86% over a 20-year period. Clozapine was neither a risk factor for all-neither cause nor cardiovascular mortality. This data suggests that long-term cardiovascular mortality continues to be increased in schizophrenia for those who are or have been cigarette smokers.

A Cluster-Randomized Clinical Trial Testing the Effectiveness of the Addressing Tobacco Through Organizational Change Model for Improving the Treatment of Tobacco Use in Community Mental Health Care: Preliminary Study Feasibility and Baseline Findings

INTRODUCTION

People with mental illness are more likely to smoke and less likely to receive tobacco treatment than the general population. The Addressing Tobacco Through Organizational Change (ATTOC) approach supports organizational change to increase tobacco treatment in this population. We describe preliminary study feasibility and baseline behaviors and attitudes among clients and staff regarding tobacco treatment, and assesse correlates of treatment of smoking.

METHODS

Preliminary accrual, engagement, and baseline data are reported from a cluster-randomized trial comparing ATTOC to usual care. Feasibility, thus far, was the rate of site and participant accrual and engagement (eg, participants remaining in the trial). Correlates of assessing smoking, advising cessation, and providing treatment were assessed.

RESULTS

Site and participant accrual is 80% (8/10) and 86% (456/533), and engagement is 100% and 82%. "Staff asking about smoking" was reported by 63% of clients and 38% of staff; "staff advising cessation" was reported by 57% of clients and 46% of staff; staff report "assisting clients with any medication" at most 22% of the time, whereas at most 18% of clients report receiving a cessation medication; 59% of clients want tobacco treatment, but 36% of staff think that it is part of their job. "Staff assisting with medications" is related to more training, believing treating smoking is part of their job, and believing patients are concerned about smoking (ps < .05).

CONCLUSIONS

This trial of training in tobacco treatment within mental health care is feasible thus far; self-reported rates of tobacco treatment are low and associated with clinician attitudes and barriers.

IMPLICATIONS

Evaluation of ways to help address tobacco use treatment in community mental health care is feasible and needed, including the use of technical assistance and training guided by an organizational change approach.

Nicotine dependence in community-dwelling Chinese patients with schizophrenia

Background

Smoking is a serious public health problem. Patients with schizophrenia usually have a higher prevalence of smoking than the general population, but the level of nicotine dependence is seldom studied, especially for patients living in the communities.

Aims

This study aimed to examine the level of nicotine dependence in Chinese community-dwelling patients with schizophrenia and explored its associated sociodemographic and clinical factors.

Methods

A total of 621 patients with schizophrenia treated in the primary care centres of Guangzhou were consecutively recruited. The level of nicotine dependence was assessed with the Chinese version of the Fagerström Test for Nicotine Dependence (FTND).

Results

148 patients with schizophrenia were current smokers, and the mean (SD) score of FTND was 5.06 (2.55) for all the current smokers. The prevalence of nicotine addiction was 48.0% (95% CI: 40.0%-56.0%) in patients with current smoking. The patients with schizophrenia had a significantly higher level of nicotine dependence than the Chinese general population. Multiple linear regression analysis revealed that male gender, being unemployed, having a family history of psychiatric disorders, having major medical conditions, first illness episode and less severe positive symptoms were significantly associated with a higher level of nicotine dependence.

Conclusion

Community-dwelling patients with schizophrenia in China, especially male patients, had a higher level of nicotine dependence than the general population.

Prevalence and Correlates of Electronic Cigarette Use Among a Clinical Sample of Polysubstance Users in Kentucky: Long Live the Cigarette?

BACKGROUND

E-cigarette use has increased in the US, yet, in some regions rates of cigarette use remain high.

PURPOSE

To describe the prevalence and features of lifetime and past-year e-cigarette use among a clinical sample of polysubstance users in Kentucky, and to determine significant associations of past-year e-cigarette use.

RESULTS

Of the final sample (N  =  497), 83.5% reported having ever used e-cigarettes and 97.2% reported having ever used cigarettes. These rates surpass those found among Kentucky's general population. Compared to those who did not report e-cigarette use, e-cigarette users were more likely to be younger ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mover><mml:mrow><mml:mi>x</mml:mi></mml:mrow><mml:mo>¯</mml:mo></mml:mover></mml:math> = 33.4 vs. 43.6, p<.001) and White (88.2.1% vs. 62.5%, p = .001). E-cigarette users showed higher rates for lifetime incarceration (91.1% vs. 72.8%, p = .001) and past-year arrest (75.0% vs. 47.5%, p = .001). This group also presented with more severe substance use history and lower mean age for illicit drug use initiation ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mover><mml:mrow><mml:mi>x</mml:mi></mml:mrow><mml:mo>¯</mml:mo></mml:mover></mml:math> = 13.8 vs. 16.4, p  =  .001). Approximately 65% of the sample reported past-year e-cigarette use and 96.6% reported past-year cigarette use. Logistic regression indicated that being younger (AOR = .973, p = .030), White (AOR = 1.92, .046), having a past-year arrest (AOR = 1.73, p = .047) and having used cigarettes (AOR = 8.93, p = .001) or kratom (AOR = 3.04, p = .025) within the past year were significantly associated with past-year e-cigarette use.

CONCLUSIONS

E-cigarette use was related to more severe drug-using patterns. Rates of dual tobacco use among this sample are high, particularly among younger individuals. In ecological contexts where cigarette use remains normative, it is likely that dual use will persist for nicotine-dependent, polysubstance-using individuals.

Association between lower estimated premorbid intelligence quotient and smoking behavior in patients with schizophrenia

Aim

We aimed to investigate the involvement of premorbid intelligence quotient in higher prevalence of smoking in patients with schizophrenia.

Methods

Participants included 190 patients with schizophrenia (mean ± standard deviation age: 37.7 ± 10.8 years; 88 males and 102 females) and 312 healthy individuals (mean ± standard deviation age: 38.1 ± 13.8; 166 males and 146 females), matched for age, sex, and ethnicity (Japanese). Premorbid intelligence quotient was estimated using the Japanese Adult Reading Test and distress symptoms were assessed using the Hopkins Symptom Check List. Current smoking information was collected according to self-declarations.

Results

As expected, the smoking rate was higher, while mean education level and Japanese Adult Reading Test scores were significantly lower, in patients with schizophrenia than in healthy individuals (p < 0.01). The mean education level and Japanese Adult Reading Test scores were significantly lower in the smoker group than in the non-smoker group in both patients and healthy individuals (p < 0.05). In the patient group alone, Hopkins Symptom Check List subscale and total scores were significantly higher in the smoker group than in the non-smoker group (p < 0.05). A multivariate regression analysis showed that the Japanese Adult Reading Test score was a significant and negative predictor for smoking (p < 0.001, odds ratio = 0.97; 95% confidence interval: 0.96–0.99).

Conclusion

Our results suggest that lower estimated premorbid intelligence quotient is an important variable in elucidating smoking behavior in humans and may be associated with higher prevalence of smoking in patients with schizophrenia.

•

Lower premorbid intelligence quotient (IQ) was observed in patients with schizophrenia who were smokers.

•

Lower education level was observed in patients with schizophrenia who were smokers.

•

Lower premorbid IQ and education level were also seen in smokers in the healthy group.

•

Distress symptoms were higher in smokers with schizophrenia.

•

In total, premorbid IQ was a negative predictor for smoking.

Neuropharmacology of attention

Early philosophers and psychologists defined and began to describe attention. Beginning in the 1950's, numerous models of attention were developed. This corresponded with an increased understanding of pharmacological approaches to manipulate neurotransmitter systems. The present review focuses on the knowledge that has been gained about these neurotransmitter systems with respect to attentional processing, with emphasis on the functions mediated within the medial prefrontal cortex. Additionally, the use of pharmacotherapies to treat psychiatric conditions characterized by attentional dysfunction are discussed. Future directions include developing a more comprehensive understanding of the neural mechanisms underlying attentional processing and novel pharmacotherapeutic targets for conditions characterized by aberrant attentional processing.

Prevalence of smoking in a psychiatric hospital and its relationship with respiratory symptoms and the prevalence of COPD

Purpose

Psychiatric patients present an elevated rate of smoking, and the smoking habit is related to a high morbidity and mortality in this collective. The aim of this study was to determine the prevalence of smoking in patients admitted for psychiatric disorders and its relationship with respiratory disease, the prevalence of COPD, and alterations in the quality of life.

Patients and methods

A cross-sectional, observational study was conducted and detailed information on smoking and respiratory symptomatology was obtained. The study participants underwent the following tests: spirometry with bronchodilator test, Fagerström test, determination of physical activity using the LCADL questionnaire, and evaluation of quality of life with the EuroQoL-5 Dimensions EQ-5D questionnaire.

Results

Two hundred seventy-six patients (mean age 56.8 years) were included: 155 with schizophrenia (87.7% smokers), 46 with depressive or anxiety disorders (54.3% smokers), and 49 and 25 with intellectual disability and dementia (43.2% smokers), respectively. The mean Fagerström test score was 5.75 points. Smokers presented with cough (47.6%), expectoration (41.4%), and chronic bronchitis (36.6%). The prevalence of COPD in the total population was 28.9%. The EQ-5D and LCADL scores were better in smokers because of their younger age and lesser psychiatric involvement. A high prevalence of smoking was observed in the psychiatric population studied, and 28.9% were diagnosed with COPD.

Conclusion

Smokers presented many more respiratory symptoms and chronic bronchitis but did not present a worse quality of life or physical activity due to their younger age and milder psychiatric involvement.

[General medical care in French psychiatric units for inmates: A national survey]

OBJECTIVES

The UHSA (UHSA) are French psychiatric units for inmates which admit detainees suffering from a psychiatric disorder requiring full-time hospital care. Non-psychiatric pathologies are overrepresented in patients with psychiatric disorders but also in detainees. As a result, patients hospitalized in UHSA are largely exposed to non-psychiatric conditions, and exploring the organization of general medical care for these patients appears very relevant. The aim of this study is to review the general medical care in all French UHSA.

METHODS

A descriptive study was carried out through a survey of the nine facilities.

RESULTS

All UHSA benefit from the intervention of a general practitioner. The physical clinical examination, the biological assessment and the electrocardiogram are systematically performed at the patient's admission in 7, 5 and 9 establishments, respectively. However, the offer of general medical care in UHSA seems disparate and sometimes insufficient. Specialized consultations are regularly requested during hospitalizations, but no establishment benefits from a telemedicine system or specialized consultations on site. The extraction of the patient to the general hospital is therefore systematic when such a consultation is needed. But the number of penitentiary escorts per day is limited. In 6 UHSA, medical extractions are thus regularly canceled by the penitentiary administration, sometimes without a medical opinion. Finally, the patient's regular physician is only contacted in 3 UHSA during hospitalizations.

CONCLUSION

Based on these results, ways of improving the organization of general medical care in UHSA are proposed through four main axes: the structure and general organization; the general medical care; the link with the healthcare partners and the articulation with the penitentiary administration.

Minimal effects of prolonged smoking abstinence or resumption on cognitive performance challenge the "self-medication" hypothesis in schizophrenia

One prominent, long-standing view is that individuals with schizophrenia smoke cigarettes more than the general population to "self-medicate" cognitive deficits and other symptoms. This study tested the self-medication hypothesis by examining the effects of smoking abstinence and resumption on cognition in patients with schizophrenia. Nicotine-dependent smokers with schizophrenia (n=26) were trained on a cognitive battery and then hospitalized to achieve and maintain confirmed abstinence from smoking for ~1 week. Cognition was tested while smoking as usual (baseline), one day after smoking cessation (early abstinence), ~1 week later (extended abstinence), and within ~3 weeks of resuming smoking (resumption). The test battery included measures of processing speed, attention, conflict resolution, verbal memory, working memory, verbal fluency, and executive function to evaluate multiple cognitive domains affected by schizophrenia. Positive and negative symptoms of schizophrenia, depressive symptoms, and dyskinesia were also measured at baseline and after prolonged abstinence. There were no significant changes in global cognitive test performance with smoking cessation, abstinence, or resumption. There were small decreases in a measure of processing speed and delayed verbal recall with abstinence, but these findings failed to survive adjustments for multiple comparisons. Surprisingly, in this within subject "On-Off-Off-On" design, there were no significant effects of early or prolonged abstinence from smoking on cognitive and behavioral measures in smokers with schizophrenia. The results of this study challenge the widely held "self-medication" hypothesis of smoking and schizophrenia, question the extent of pro-cognitive effects of smoking and nicotine in schizophrenia, and support encouraging smoking cessation in schizophrenia.

Smoking by people with mental illness and benefits of smoke-free mental health services

Smoking is the largest single cause of preventable illness in the UK. Those with mental health problems smoke significantly more and are therefore at greater risk. The new Health Act (2006) will require mental health facilities in England to be completely smoke-free by 1st July 2008. This article reviews the current literature regarding how smoking affects both the physical and mental well-being of people with mental health problems. It also considers the effects of smoke-free policy in mental health settings.

Getting a Handle on Neuropharmacology by Targeting Receptor-Associated Proteins

Targeted therapy for neuropsychiatric disorders requires selective modulation of dysfunctional neuronal pathways. Receptors relevant to CNS disorders typically have associated proteins discretely expressed in specific neuronal pathways; these accessory proteins provide a new dimension for drug discovery. Recent studies show that targeting a TARP auxiliary subunit of AMPA receptors selectively modulates neuronal excitability in specific forebrain pathways relevant to epilepsy. Other medicinally important ion channels, gated by glutamate, γ-aminobutyric acid (GABA), and acetylcholine, also have associated proteins, which may be druggable. This emerging pharmacology of receptor-associated proteins provides a new approach for improving drug efficacy while mitigating side effects.

Schizophrenia-associated methylomic variation: molecular signatures of disease and polygenic risk burden across multiple brain regions

Genetic association studies provide evidence for a substantial polygenic component to schizophrenia, although the neurobiological mechanisms underlying the disorder remain largely undefined. Building on recent studies supporting a role for developmentally regulated epigenetic variation in the molecular aetiology of schizophrenia, this study aimed to identify epigenetic variation associated with both a diagnosis of schizophrenia and elevated polygenic risk burden for the disease across multiple brain regions. Genome-wide DNA methylation was quantified in 262 post-mortem brain samples, representing tissue from four brain regions (prefrontal cortex, striatum, hippocampus and cerebellum) from 41 schizophrenia patients and 47 controls. We identified multiple disease-associated and polygenic risk score-associated differentially methylated positions and regions, which are not enriched in genomic regions identified in genetic studies of schizophrenia and do not reflect direct genetic effects on DNA methylation. Our study represents the first analysis of epigenetic variation associated with schizophrenia across multiple brain regions and highlights the utility of polygenic risk scores for identifying molecular pathways associated with aetiological variation in complex disease.

Prevalence of smoking in patients with bipolar disorder, major depressive disorder and schizophrenia and their relationships with quality of life

Few studies have compared the prevalence of smoking between patients with bipolar disorder, major depressive disorder (MDD) and schizophrenia. This study examined the prevalence of smoking and its relationships with demographic and clinical characteristics, and quality of life (QOL) in patients with these psychiatric disorders. A total of 1,102 inpatients were consecutively screened. Psychopathology and QOL were measured with standardized instruments. The prevalence of current smoking in the whole sample was 16.7%; 17.5% in bipolar disorder, 10.6% in MDD and 18.5% in schizophrenia. The rates of smoking in bipolar disorder (p = 0.004, OR = 2.5, 95%CI: 1.3–4.7) and schizophrenia (p = 0.03, OR = 2.0, 95%CI: 1.06–3.8) were significantly higher than in MDD, while no difference was found between bipolar disorder and schizophrenia. Smokers had a higher mental QOL than non-smokers (p = 0.007) in MDD, but no difference was found in the other two groups. Male gender, living alone, higher personal income, older age of onset, health insurance coverage, and first episode was significantly associated with smoking in one or more diagnostic groups. Smoking appears more common in bipolar disorder and schizophrenia than in MDD in China. The figures in all disorders were lower than that reported in most of other countries.

Repeated Nicotine Strengthens Gamma Oscillations in the Prefrontal Cortex and Improves Visual Attention

Nicotine has strong addictive as well as procognitive properties. While a large body of research on nicotine continues to inform us about mechanisms related to its reinforcing effects, less is known about clinically relevant mechanisms that subserve its cognitive-enhancing properties. Understanding the latter is critical for developing optimal strategies for treating cognitive deficits. The primary brain region implicated in cognitive functions improved by nicotine is the prefrontal cortex (PFC). Here we assessed the impact of nicotine on unit activity and local field potential oscillations in the PFC of behaving rats. An acute dose of nicotine produced a predominantly inhibitory influence on population activity, a small increase in gamma oscillations, and a decrease in theta and beta oscillations. After a daily dosing regimen, a shift to excitatory-inhibitory balance in single-unit activity and stronger gamma oscillations began to emerge. This pattern of plasticity was specific to the gamma band as lower frequency oscillations were suppressed consistently across daily nicotine treatments. Gamma oscillations are associated with enhanced attentional capacity. Consistent with this mechanism, the repeat dosing regimen in a separate cohort of subjects led to improved performance in an attention task. These data suggest that procognitive effects of nicotine may involve development of enhanced gamma oscillatory activity and a shift to excitatory-inhibitory balance in PFC neural activity. In the context of the clinical use of nicotine and related agonists for treating cognitive deficits, these data suggest that daily dosing may be critical to allow for development of robust gamma oscillations.

Long term effects of smoking cessation in hospitalized schizophrenia patients

BACKGROUND

The prevalence of smoking in patients with schizophrenia is higher than that in the general population and is an important medical issue. Short-term smoking cessation tends to worsen psychiatric symptoms in patients with schizophrenia but decreases sympathetic nervous system activity and improves plasma cholesterol levels in healthy people. Few studies have assessed the long-term effects of smoking cessation in patients with schizophrenia.

METHODS

Subjects were 70 Japanese patients with schizophrenia (38 smokers, 32 non-smokers). We compared the following clinical parameters between the two groups at baseline (before smoking cessation) and in each group separately between baseline and at three years after smoking cessation: autonomic nervous system activity, plasma cholesterol levels, body weight, drug therapy, and Global Assessment of Functioning scores. We also compared the mean changes in clinical parameters throughout this study between the groups at both time points. Autonomic nervous system activity was assessed by power spectral analysis of heart rate variability.

RESULTS

Parasympathetic nervous system activity and the doses of antiparkinsonian drugs in smokers were significantly higher than those in non-smokers at baseline. Smoking cessation was associated with significantly decreased sympathetic nervous system activity and decreased doses of antipsychotics and antiparkinsonian drugs at three years after smoking cessation. However, there was no significant difference in the mean change in clinical factors scores, except for Global Assessment of Functioning scores, between smokers and non-smokers at three years after smoking cessation.

CONCLUSIONS

Our results suggest that smoking reduces both autonomic nervous system activity and the effectiveness of drug therapy with antipsychotics and antiparkinsonian drugs in patients with schizophrenia, but that both factors could be ameliorated over the long term by smoking cessation. Taken together with the findings of previous studies, smoking cessation in patients with schizophrenia has many long-term positive physiological effects.

Investigating causality in associations between smoking initiation and schizophrenia using Mendelian randomization

Smoking is strongly associated with schizophrenia. Although it has been widely assumed that this reflects self-medication, recent studies suggest that smoking may be a risk factor for schizophrenia. We performed two-sample bi-directional Mendelian randomization using summary level genomewide association data from the Tobacco And Genetics Consortium and Psychiatric Genomics Consortium. Variants associated with smoking initiation and schizophrenia were combined using an inverse-variance weighted fixed-effects approach. We found evidence consistent with a causal effect of smoking initiation on schizophrenia risk (OR 1.73, 95% CI 1.30-2.25, p < 0.001). However, after relaxing the p-value threshold to include variants from more than one gene and minimize the potential impact of pleiotropy, the association was attenuated (OR 1.03, 95% CI 0.97-1.09, p = 0.32). There was little evidence in support of a causal effect of schizophrenia on smoking initiation (OR 1.01, 95% CI 0.98-1.04, p = 0.32). MR Egger regression sensitivity analysis indicated no evidence for pleiotropy in the effect of schizophrenia on smoking initiation (intercept OR 1.01, 95% CI 0.99-1.02, p = 0.49). Our findings provide little evidence of a causal association between smoking initiation and schizophrenia, in either direction. However, we cannot rule out a causal effect of smoking on schizophrenia related to heavier, lifetime exposure, rather than initiation.

Interventions to encourage uptake of cancer screening for people with severe mental illness

BACKGROUND

Adults with severe mental illness (i.e. schizophrenia or other related psychotic disorders and bipolar disorder) can be at greater risk of cancer than those without severe mental illness (SMI). Early detection of cancer through screening is effective in improving patient outcomes including death. However, people with SMI are less likely than others to take up available cancer screening.

OBJECTIVES

To determine the effectiveness of interventions targeted at adults with SMI, or their carers or health professionals, and aimed at increasing the uptake of cancer screening tests for which the adults with SMI are eligible.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Trials Register (October 25, 2012; December 19, 2014; April 07, 2015; July 04, 2016).

SELECTION CRITERIA

All randomised controlled trials (RCTs) of interventions, targeted towards adults with SMI or their carers or health professionals, to encourage uptake of cancer screening tests for which the adults with SMI were eligible.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts and assessed these against the inclusion criteria.

MAIN RESULTS

We did not find any trials that met the inclusion criteria.

AUTHORS' CONCLUSIONS

A comprehensive search showed that currently there is no RCT evidence for any method of encouraging cancer screening uptake in people with SMI. No specific approach can therefore be recommended. High-quality, large-scale RCTs are needed urgently to help address the disparity between people with SMI and others in cancer screening uptake.

Varenicline for smoking cessation and reduction in people with severe mental illnesses: systematic review and meta-analysis

AIMS

To determine the effectiveness and safety of varenicline in treating tobacco dependence in patients with severe mental illness.

DESIGN

A systematic review and meta-analysis of randomised controlled trials that compared varenicline with a placebo or an alternative intervention for smoking cessation or reduction.

SETTING

Both in- and out-patient settings in any country.

PARTICIPANTS

Adult patients aged 18 years and over with any type of severe mental illness. The systematic review included eight studies comprising 398 participants.

MEASURES

Primary outcome measures were (1) smoking cessation, (2) smoking reduction measured by changes in the number of cigarettes smoked per day and (3) number of psychiatric adverse events, which were collected at the end of treatment.

FINDINGS

The random-effect pooled estimates from the five studies that reported smoking-related outcomes found that varenicline is statistically superior to placebo in smoking cessation [risk ratios 4.33; 95% confidence interval (CI) = 1.96-9.56], and smoking reduction was higher in varenicline groups (mean reduced daily cigarettes was 6.39; 95% CI = 2.22-10.56). There is no significant difference regarding neuropsychiatric and other adverse events.

CONCLUSIONS

Varenicline appears to be significantly more effective than placebo in assisting with smoking cessation and reduction in people with severe mental illness. There appears to be no clear evidence that varenicline was associated with an increased risk of neuropsychiatric or other adverse events compared with placebo.

Blood Levels of Monoamine Precursors and Smoking in Patients with Schizophrenia

Smoking is highly prevalent in patients with schizophrenia and exerts a negative impact on cardiovascular mortality in these patients. Smoking has complex interactions with monoamine metabolism through the ability of cigarette smoke to suppress Type 1 T helper cell (Th1) type immunity, the immunophenotype that is implicated in phenylalanine hydroxylase (PAH) dysfunction and tryptophan (Trp) breakdown to kynurenine (Kyn) via indoleamine 2,3-dioxygenase. Nicotine also induces tyrosine hydroxylase (TH) gene expression, leading to increased synthesis of catecholamines. Furthermore, there is evidence for PAH dysfunction in schizophrenia. This study aimed to compare the plasma levels of selected monoamine precursors and their metabolites in smokers vs. non-smokers in a large sample of patients with schizophrenia. We measured plasma phenylalanine (Phe), tyrosine (Tyr), Trp, and Kyn levels using high-performance liquid chromatography and calculated Phe:Tyr and Kyn:Trp ratios in 920 patients with schizophrenia. Analysis of variance and linear regression analyses were used to compare these endpoints between three groups of patients with schizophrenia: (1) current smokers, (2) past smokers, and (3) non-smokers. There were significant differences among the three groups with regards to Tyr levels [F_(2,789) = 3.77, p = 0.02], with current smokers having lower Tyr levels when compared with non-smokers (p = 0.02). Kyn levels and Kyn:Trp ratio were different among the three groups [F_(2,738) = 3.17, p = 0.04, F_(2,738) = 3.61, p = 0.03] with current smokers having lower Kyn levels (p = 0.04) and higher Kyn:Trp ratio (p = 0.02) when compared with past smokers. These findings need to be replicated with protocols that include healthy controls to further elucidate the neurobiological underpinnings of altered Tyr and Kyn levels in smokers. Results do suggest potential molecular links between schizophrenia and smoking that may represent biomarkers and treatment targets for reducing an important modifiable cause of general morbidity and mortality in patients with schizophrenia.

History of major depression as a barrier to health behavior changes after a chronic disease diagnosis

OBJECTIVE

To examine whether changes in smoking, drinking, and physical activity after a chronic disease diagnosis differ between middle-aged and older adults with and without a history of major depression.

METHODS

Individual-level data came from 1996 to 2010 waves of the U.S. Health and Retirement Study. Chronic disease diagnosis was ascertained from self-reports of physician diagnosed diseases. Major depression was assessed by the short-form Composite International Diagnostic Interview. Mixed-effects logistic regressions were performed to estimate the potential moderating effect of a history of major depression.

RESULTS

Baseline major depression was associated with a more than 3-fold increase (OR=4.48, 95% CI=2.27-8.86) in the odds of smoking and 37% decrease (OR=0.63, 95% CI=0.52-0.75) in the odds of staying physically active, but not with odds of excessive drinking. After a chronic disease diagnosis, the odds of smoking was reduced by 75% (OR=0.25, 95% CI=0.20-0.32), the odds of excessive drinking was reduced by 47% (OR=0.53, 95% CI=0.47-0.61), and the odds of staying physically active was reduced by 30% (OR=0.70, 95% CI=0.63-0.78). There was a significant interaction effect for smoking such that the decline in the odds of smoking was smaller among adults with a history of major depression.

CONCLUSION

Chronic disease diagnosis may be an important teachable moment for health behavior change, but the behavior changing effect may be smaller for those with a history of major depression especially when it comes to smoking.

Metabolomic Profiling of Post-Mortem Brain Reveals Changes in Amino Acid and Glucose Metabolism in Mental Illness Compared with Controls

Metabolomic profiling was carried out on 53 post-mortem brain samples from subjects diagnosed with schizophrenia, depression, bipolar disorder (SDB), diabetes, and controls. Chromatography on a ZICpHILIC column was used with detection by Orbitrap mass spectrometry. Data extraction was carried out with m/z Mine 2.14 with metabolite searching against an in-house database. There was no clear discrimination between the controls and the SDB samples on the basis of a principal components analysis (PCA) model of 755 identified or putatively identified metabolites. Orthogonal partial least square discriminant analysis (OPLSDA) produced clear separation between 17 of the controls and 19 of the SDB samples (R2CUM 0.976, Q2 0.671, p-value of the cross-validated ANOVA score 0.0024). The most important metabolites producing discrimination were the lipophilic amino acids leucine/isoleucine, proline, methionine, phenylalanine, and tyrosine; the neurotransmitters GABA and NAAG and sugar metabolites sorbitol, gluconic acid, xylitol, ribitol, arabinotol, and erythritol. Eight samples from diabetic brains were analysed, six of which grouped with the SDB samples without compromising the model (R2 CUM 0.850, Q2 CUM 0.534, p-value for cross-validated ANOVA score 0.00087). There appears on the basis of this small sample set to be some commonality between metabolic perturbations resulting from diabetes and from SDB.

Cigarette and waterpipe smoking among adult patients with severe and persistent mental illness in Bahrain: a comparison with the National Non-communicable Diseases Risk Factors Survey

BACKGROUND

Smoking has been associated with several types of mental illness namely schizophrenia, depression, bipolar disorders with a prevalence of smoking twice that of the general population. The study objective was to ascertain whether waterpipe tobacco smoking (WTS), cigarette smoking and all types of tobacco smoking are more common among Bahraini patients with severe and persistent mental illness (SPMI) than the general population.

METHODS

A cross-sectional study was conducted on 222 adult SPMI both in- and out- patients who attended the Psychiatric Hospital in Bahrain. A 29-item questionnaire, which included sociodemographic variables, pattern and history of psychiatric illness and a comprehensive smoking history, was used. Comparative smoking data were obtained from the Bahraini National Non-communicable Diseases Risk Factors Survey.

RESULTS

The prevalence of smoking of tobacco among SPMI patients was 30.2 % compared to 19.9 % in the general population. The corresponding values for cigarette smoking were 25.2, 13.8 %, respectively and for WTS, 11.3, 8.4 %, respectively. SPMI patients were 1.7 (95 % CI 1.3, 2.4 %) times more likely to be smokers, 2.1 (95 % CI 1.5, 2.9 %) times, cigarette smokers and 1.4 (95 % CI 0.9, 1.9 %) times WTS than the general population. SPMI patients smoked at a younger age and consumed more cigarettes than the general population. The mean age started smoking was lower among men than women, similar for cigarettes, and higher for WTS.

CONCLUSIONS

The prevalence of smoking among patients with SPMI in Bahrain is twice that of the general population. The findings of the study have implications on the provision of healthcare to mentally ill patients in the country.

Does Cannabis Cause, Exacerbate or Ameliorate Psychiatric Disorders? An Oversimplified Debate Discussed

There have been extensive policy shifts in the legality of recreational and therapeutic use of cannabis in the United States, as well as a steady increase in the number of people using the drug on a regular basis. Given these rapid societal changes, defining what is known scientifically about the consequences of cannabis use on mental health takes on added public health significance. The purpose of this circumspectives piece is to discuss evidence of cannabis' effects on two psychiatric conditions: post-traumatic stress disorder and psychotic disorders. Dr Haney and Dr Evins will discuss two viewpoints regarding the benefit and harm of cannabis use for these conditions, while outlining what remains unproven and requires further testing to move the field forward.

Effects of transcranial direct current stimulation (tDCS) on cognition, symptoms, and smoking in schizophrenia: A randomized controlled study

Schizophrenia is characterized by cognitive deficits which persist after acute symptoms have been treated or resolved. Transcranial direct current stimulation (tDCS) has been reported to improve cognition and reduce smoking craving in healthy subjects but has not been as carefully evaluated in a randomized controlled study for these effects in schizophrenia. We conducted a randomized double-blind, sham-controlled study of the effects of 5 sessions of tDCS (2 milliamps for 20minutes) on cognition, psychiatric symptoms, and smoking and cigarette craving in 37 outpatients with schizophrenia or schizoaffective disorder who were current smokers. Thirty subjects provided evaluable data on the MATRICS Consensus Cognitive Battery (MCCB), with the primary outcome measure, the MCCB Composite score. Active compared to sham tDCS subjects showed significant improvements after the fifth tDCS session in MCCB Composite score (p=0.008) and on the MCCB Working Memory (p=0.002) and Attention-Vigilance (p=0.027) domain scores, with large effect sizes. MCCB Composite and Working Memory domain scores remained significant at Benjamini-Hochberg corrected significance levels (α=0.05). There were no statistically significant effects on secondary outcome measures of psychiatric symptoms (PANSS scores), hallucinations, cigarette craving, or cigarettes smoked. The positive effects of tDCS on cognitive performance suggest a potential efficacious treatment for cognitive deficits in partially recovered chronic schizophrenia outpatients that should be further investigated.

Assessing the synergy between cholinomimetics and memantine as augmentation therapy in cognitive impairment in schizophrenia. A virtual human patient trial using quantitative systems pharmacology

While many drug discovery research programs aim to develop highly selective clinical candidates, their clinical success is limited because of the complex non-linear interactions of human brain neuronal circuits. Therefore, a rational approach for identifying appropriate synergistic multipharmacology and validating optimal target combinations is desperately needed. A mechanism-based Quantitative Systems Pharmacology (QSP) computer-based modeling platform that combines biophysically realistic preclinical neurophysiology and neuropharmacology with clinical information is a possible solution. This paper reports the application of such a model for Cognitive Impairment In Schizophrenia (CIAS), where the cholinomimetics galantamine and donepezil are combined with memantine and with different antipsychotics and smoking in a virtual human patient experiment. The results suggest that cholinomimetics added to antipsychotics have a modest effect on cognition in CIAS in non-smoking patients with haloperidol and risperidone and to a lesser extent with olanzapine and aripiprazole. Smoking reduces the effect of cholinomimetics with aripiprazole and olanzapine, but enhances the effect in haloperidol and risperidone. Adding memantine to antipsychotics improves cognition except with quetiapine, an effect enhanced with smoking. Combining cholinomimetics, antipsychotics and memantine in general shows an additive effect, except for a negative interaction with aripiprazole and quetiapine and a synergistic effect with olanzapine and haloperidol in non-smokers and haloperidol in smokers. The complex interaction of cholinomimetics with memantine, antipsychotics and smoking can be quantitatively studied using mechanism-based advanced computer modeling. QSP modeling of virtual human patients can possibly generate useful insights on the non-linear interactions of multipharmacology drugs and support complex CNS R&D projects in cognition in search of synergistic polypharmacy.