Smoking in first-episode patients with schizophrenia

Responses to Tobacco Smoking-Related Health Messages in Young People With Recent-Onset Schizophrenia

Virtually no research has examined the responses of youth with recent-onset psychosis (ROP) to smoking-related health warnings. We examined predictors of response and tested hypotheses that participants with ROP would (a) assess warnings as less effective than a healthy comparison (HC) group, and (b) assess video warnings as more effective than pictures. ROP participants (n = 69) had <2 years of prior antipsychotic treatment; the HC group (n = 79) had no major mental illness. Participants viewed 10 pictorial warnings, 8 videos depicting similar messages, and were interviewed regarding tobacco use, health literacy, and smoking knowledge. We assessed response at baseline and at 4-week follow-up. ROP participants were more likely than HC to smoke tobacco (49.3% vs 10.1%) and had lower levels of health literacy and smoking-related knowledge. Cannabis was used by 46.4% of ROP participants. Effectiveness ratings were high for both picture and video warnings with no differences between media. ROP participants compared to HC and nonsmokers compared to smokers were more likely to perceive warnings as effective. Effectiveness was associated with negative affect and greater emotional arousal. We assessed 33 smokers at follow-up; 5 (15%) identified as nonsmokers, 15 (45%) made a quit attempt, and 16 (49%) reported that the warnings influenced their smoking. Results indicate that young people with psychotic disorders respond favorably to health warnings. Effective messages depict health consequences clearly, elicit negative emotions, and may impact smoking behavior. Future research is needed to understand the effects of mode of presentation and message comprehension on smoking behavior.

Does tobacco use cause psychosis? Systematic review and meta-analysis

BACKGROUND

Although the association between psychotic illness and cigarette smoking is well known, the reasons are unclear why people with psychosis are more likely to smoke than are the general population. We aimed to test several hypotheses. First, that daily tobacco use is associated with an increased risk of psychotic illness in both case-control and prospective studies. Second, that smoking is associated with an earlier age at onset of psychotic illness. Finally, that an earlier age at initiation of smoking is associated with an increased risk of psychosis. We also aimed to derive an estimate of the prevalence of smoking in patients presenting with their first episode of psychosis.

METHODS

We searched Embase, Medline, and PsycINFO and selected observational studies in which rates of smoking were reported in people with psychotic disorders, compared with controls. We calculated the weighted mean difference for age at onset of psychosis and age at initiation of smoking. For categorical outcomes, we calculated odds ratios from cross-sectional studies and risk ratios from prospective studies.

FINDINGS

Of 3717 citations retrieved, 61 studies comprising 72 samples met inclusion criteria. The overall sample included 14 555 tobacco users and 273 162 non-users. The prevalence of smoking in patients presenting with their first episode of psychosis was 0·57 (95% CI 0·52-0·62; p<0·0001). In case-control studies, the overall odds ratio for the first episode of psychosis in smokers versus non-smokers was 3·22 (95% CI 1·63-6·33), with some evidence of publication bias (Egger's test p=0·018, Begg's test p=0·007). For prospective studies, we calculated an overall relative risk of new psychotic disorders in daily smokers versus non-smokers of 2·18 (95% CI 1·23-3·85). Daily smokers developed psychotic illness at an earlier age than did non-smokers (weighted mean difference -1·04 years, 95% CI -1·82 to -0·26). Those with psychosis started smoking at a non-significantly earlier age than did healthy controls (-0·44 years, 95% CI -1·21 to 0·34).

INTERPRETATION

Daily tobacco use is associated with increased risk of psychosis and an earlier age at onset of psychotic illness. The possibility of a causal link between tobacco use and psychosis merits further examination.

FUNDING

NIHR Maudsley Biomedical Research Centre.

Smoking topography and outcome expectancies among individuals with schizotypy

Compared to smokers in the general population, smokers with schizophrenia smoke more cigarettes per day and have higher nicotine dependence and biochemical indicators of nicotine intake. They also have more intense smoking topography and greater positive smoking expectancies. Little is known about the relationship between smoking and schizotypy, defined as the personality organization reflecting a vulnerability to schizophrenia-spectrum pathology. This study assessed schizotypy symptoms, smoking characteristics and behaviors, and smoking expectancies in young adults with psychometrically defined schizotypy and demographically matched controls without schizotypy. Smokers with schizotypy had higher nicotine dependence and smoked more cigarettes per week compared to control smokers. They were also more likely to endorse greater positive consequences (i.e., improved state enhancement, stimulation, social facilitation, taste/sensorimotor manipulation, reduced negative affect and boredom) and fewer negative consequences of smoking. Smokers with schizotypy and control smokers did not differ on smoking topography or carbon monoxide levels. This is the first known study to investigate relationships between these smoking-related variables in smokers with schizotypy. Individuals with schizotypy possessed certain smoking-related characteristics and smoking expectancies similar to those with schizophrenia. This offers preliminary insight into unique smoking-related factors among individuals with schizotypy and highlights the importance of continued research in this area.

Mechanisms underlying the comorbidity of tobacco use in mental health and addictive disorders

We discuss potential explanations for the high prevalence of tobacco use and tobacco dependence (TD) in people with mental health and addictive (MHA) disorders. The biopsychosocial basis for this comorbidity is presented, integrating evidence from epidemiologic and clinical studies. We also review evidence that suggests a shared vulnerability related to biological, genetic, and environmental factors may be the most parsimonious mechanism to explain the association between TD and MHA disorders. Finally, we review the examples of various MHA disorders that are associated with TD, and suggest avenues for new investigation that could aid in the development of rationale and more effective treatments for tobacco and MHA disorder comorbidities.

Atypical antipsychotics as noncompetitive inhibitors of alpha4beta2 and alpha7 neuronal nicotinic receptors

It has been suggested that the interaction of antipsychotic medications with neuronal nicotinic receptors may increase the cognitive dysfunction associated with schizophrenia and may explain why current therapies only partially address this core feature of the illness. In the present studies we compared the effects of the atypical antipsychotics quetiapine, clozapine and N-desmethylclozapine to those of the typical antipsychotics haloperidol and chlorpromazine on the alpha4beta2 and alpha7 nicotinic receptor subtypes. The binding of [(3)H]-nicotine to rat cortical alpha4beta2 receptors and [(3)H]-methyllycaconitine to rat hippocampal alpha7 receptors was not affected by any of the compounds tested. However, Rb(+) efflux evoked either by nicotine or the selective alpha4beta2 agonist TC-1827 from alpha4beta2 receptors expressed in SH-EP1 cells and nicotine-evoked [(3)H]-dopamine release from rat striatal synaptosomes were non-competitively inhibited by all of the antipsychotics. Similarly, alpha-bungarotoxin-sensitive epibatidine-evoked [(3)H]-norepinephrine release from rat hippocampal slices and acetylcholine-activated currents of alpha7 nicotinic receptors expressed in oocytes were inhibited by haloperidol, chlorpromazine, clozapine and N-desmethylclozapine. The inhibitory effects on nicotinic receptor function produced by the antipsychotics tested occurred at concentrations similar to plasma levels achieved in schizophrenia patients, suggesting that they may lead to clinically relevant effects on cognition.

Cognitive performance and cigarette smoking in first-episode psychosis

The purpose of this study is to describe possible differences in cognitive functioning between smoking and non-smoking patients with first-episode psychosis and to determine whether there is a better cognitive profile associated with smoking. We assessed 61 first-episode psychosis patients with a neuropsychological battery that included computerized measurements of attention, working memory, and executive functioning. Patients were grouped into two categories: non-smokers (0 cigarettes/day; n = 30) and smokers (>/=20 cigarettes/day; n = 31). No significant differences were detected in sociodemographic and clinical data between the two groups. For attention tasks, smokers exhibited shorter reaction times in the sustained attention test than non-smokers (P = 0.039) and needed less time to complete the Stroop interference test (P = 0.013). In the working memory task, smokers exhibited shorter reaction times (P = 0.029) and presented a significantly lower percentage of omission (P = 0.002) and commission errors (P = 0.020) than non-smokers. For executive functioning, no differences were detected between groups in performance on the Wisconsin Card Sorting Test. Results indicate that first-episode psychosis patients who are nicotine users have better cognitive functioning in the areas of attention and working memory than patients who are not nicotine users. This study supports the cognitive approach to the self-medication hypothesis, to explain the high rates of cigarette smoking among psychosis patients. These results may be relevant for developing new strategies involving nicotinic receptors for cognitive enhancement in psychosis.

Early treatment-related changes in diabetes and cardiovascular disease risk markers in first episode psychosis subjects

OBJECTIVE

To examine prospective changes in cardiovascular disease (CVD) and type-2 diabetes risk factors in young adult first episode psychotic (FEP) patients treated with second generation antipsychotic medications.

METHODS

At baseline, fasting serum and anthropometric measures were obtained from 45 FEP patients and 41 healthy adults (controls) of similar age, ethnicity and sex; sixteen of the FEP patients remained on the same antipsychotic medication and were available for a second blood draw at 24 weeks of treatment. Serum was assayed for glucose, insulin, triglycerides, total cholesterol and high and low density lipoproteins (HDL, LDL), adiponectin, leptin, interleukin 6, E-selectin and VCAM-1. Wilcoxon nonparametric tests were used to compare risk markers between the FEP and control group at baseline and to evaluate pre-post treatment changes within the FEP group.

RESULTS

At baseline, the distributions of risk marker values were similar between the two groups and the percentages of FEP patients and healthy controls who were overweight/obese, dyslipidemic, hyperglycemic, and hyperinsulinemic did not differ. At 24 weeks, compared to baseline, FEP patients showed significant increases in BMI (p=0.0002), glucose (p=0.0449), insulin (p=0.0161), cholesterol (p=0.0129), leptin (p=0.0215), and E-selectin (p=0.0195), and a decrease in adiponectin (p=0.0371).

CONCLUSIONS

Among patients with first episode psychosis, 6-month treatment with second generation antipsychotics is associated with the exacerbation of pre-existing and emergence of new CVD and diabetes risk factors.

Medications Development for the Treatment of Nicotine Dependence in Individuals with Schizophrenia

The development of medications for the treatment of nicotine dependence in patients with schizophrenia is a public health priority due to its high prevalence rates, devastating medical consequences, and difficulty to treat. It has been hypothesized that the high prevalence of nicotine dependence among patients with schizophrenia may be due to a shared neurobiological vulnerability. This shared vulnerability has been evidenced in reports showing that nicotine improves neuropsychological deficits associated with schizophrenia such as in the P50 evoked auditory potentials, spatial working memory, and attention. The common pathophysiologic pathways of smoking and schizophrenia may serve as the basis for the pharmacological evaluation of medications for the treatment of these concurrent disorders. Currently, little research of medications for the treatment of this comorbidity has been conducted. Studies have evaluated the efficacy of smoking cessation medications in patients with schizophrenia. These include the nicotine replacement therapy (patch, nasal spray) and sustained release bupropion. Others have evaluated the anti-smoking effect of medications (e.g., clozapine, haloperidol) used for the treatment of schizophrenia. In both cases, the results have not been conclusive. Newer smoking cessation approaches such as varenicline, selegiline, rimonabant, and nicotine vaccine, among others, have yet to be tested in this population. The purpose of this article is to review the results of the studies conducted to date and propose some potential pharmacotherapies based on the current knowledge of the pathophysiology of both disorders.

Co-morbidity of smoking in patients with psychiatric and substance use disorders

This article reviews cigarette smoking in patients with psychiatric disorders (PD) and substance use disorders (SUD). Rates of smoking are approximately 23% in the U.S. population but approximately two- to four-fold higher in patients with PD and SUD. Many remaining smokers have had repeated smoking cessation failures, possibly due to the presence of co-morbid PD and SUDs. There is modest, evidence-based support for effective treatment interventions for nicotine addiction in PD and SUD. Further research is needed to increase our understanding of nicotine addiction in PD and SUD and develop more effective treatment interventions.