Effect of smoking on neuroleptics in schizophrenia

Modulation of mGlu5 reduces rewarding associative properties of nicotine via changes in mesolimbic plasticity: Relevance to comorbid cigarette smoking in psychosis

RATIONALE

Antipsychotic medications that are used to treat psychosis are often limited in their efficacy by high rates of severe side effects. Treatment success in schizophrenia is further complicated by high rates of comorbid nicotine use. Dopamine D2 heteroreceptor complexes have recently emerged as targets for the development of more efficacious pharmaceutical treatments for schizophrenia.

OBJECTIVE

The current study sought to explore the use of the positive allosteric modulator of the mGlu5 receptor 3-Cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl)benzamide (CDPPB) as a treatment to reduce symptoms related to psychosis and comorbid nicotine use.

METHODS

Neonatal treatment of animals with the dopamine D2-like receptor agonist quinpirole (NQ) from postnatal day (P)1-21 produces a lifelong increase in D2 receptor sensitivity, showing relevance to psychosis and comorbid tobacco use disorder. Following an 8-day conditioning paradigm, brain tissue in the mesolimbic pathway was analyzed for several plasticity markers, including brain derived neurotrophic factor (BDNF), phosphorylated p70 ribosomal S6 kinase (phospho-p70S6K), and cadherin-13 (Cdh13).

RESULTS

Pretreatment with CDPPB was effective to block enhanced nicotine conditioned place preference observed in NQ-treated animals. Pretreatment was additionally effective to block the nicotine-induced increase in BDNF and sex-dependent increases in cadherin-13 in the ventral tegmental area (VTA), as well as increased phospho-p70S6K in the nucleus accumbens (NAcc) shell found in NQ-treated animals.

CONCLUSION

In conjunction with prior work, the current study suggests positive allosteric modulation of the mGlu5 receptor, an emerging target for schizophrenia therapeutics, may be effective for the treatment of comorbid nicotine abuse in psychosis.

Tobacco use in schizophrenia: a study of cotinine concentrations in the saliva of patients and controls

Nicotine has been proposed to provide anxiety relief, oral gratification and self-medication of psychotic symptoms in psychiatric patients. In order to investigate the relations between psychopathology and tobacco use we measured the concentration of cotinine, the major metabolite of nicotine, in the saliva of psychiatric patients and healthy volunteers. In a sample of 42 schizophrenic patients we correlated smoking status, cotinine levels, symptom profiles (PANSS), and neuroleptic side effects (Simpson–Angus). Despite reporting the same amount of cigarettes consumed per day the saliva concentration of cotinine was significantly higher in patients with schizophrenia than in the controls. There were no significant differences in clinical characteristics between smoking and non-smoking schizophrenic patients, but smokers tended to be on higher drug doses. High cotinine concentrations correlated significantly with the negative symptoms Passive withdrawal and Social avoidance. The results indicate that the schizophrenic patients smoke cigarettes more intensely than other patients and healthy subjects. The correlation between high cotinine levels and negative symptomatology may reflect an attempt by schizophrenic patients to overcome the emotional withdrawal and thus the results may lend support to a self-medication hypothesis.

Cigarette smoking in long-term schizophrenia

Purpose

Cigarette smoking is a great health problem and prevalent among subjects with schizophrenia. Our aim was to investigate the prevalence and associations of cigarette smoking in patients with long-term schizophrenia.

Methods

Seven hundred and sixty schizophrenia patients were interviewed and their cigarette smoking was recorded.

Results

Smoking was more prevalent men than in women patients. In logistic regression analysis, male gender, duration of illness (DUI) from 10 to 19 years, being divorced or separated, lower education and high daily doses of neuroleptics (DDN) associated significantly with regular smoking. Heavy smoking associated, in men, with hospital treatment.

Conclusions

In schizophrenia patients, smoking is associated with long DUI, high DDN and institutional care. Interventions for cessation and/or reduction of cigarette smoking should be a part of the treatment for patients with schizophrenia.

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.

Selective noradrenaline reuptake inhibitors for schizophrenia

BACKGROUND

Schizophrenia is frequently a chronic and disabling illness with a heterogeneous range of symptoms. The positive symptoms usually respond to antipsychotics but the cognitive and negative symptoms of schizophrenia are difficult to treat with conventional antipsychotics and significantly impact on quality of life and social outcomes. Selective noradrenaline reuptake inhibitors (NRIs) increase prefrontal dopamine and noradrenaline levels without significantly affecting subcortical dopamine levels, making them an attractive candidate for treating cognitive and negative symptoms.

OBJECTIVES

To investigate the effects of selective noradrenaline reuptake inhibitors (NRIs), compared with a placebo or control treatment, for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Trials Register (up to 7 February 2017) which is based on regular searches of MEDLINE, Embase, CINAHL, BIOSIS, AMED, PubMed, PsycINFO, and registries of clinical trials. There are no language, date, document type, or publication status limitation for inclusion of records into the register. We inspected references of all included studies for further relevant studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing NRIs with either a control treatment or placebo for people with schizophrenia or related disorders (such as schizoaffective disorder) by any means of diagnosis. We included trials that met our selection criteria and provided useable information.

DATA COLLECTION AND ANALYSIS

We independently inspected all citations from searches, identified relevant abstracts, and independently extracted data from all included studies. For binary data we calculated risk ratio (RR), for continuous data we calculated mean difference (MD), and for cognitive outcomes we derived standardised mean difference (SMD) effect sizes, all with 95% confidence intervals (CI) and using a random-effects model. We assessed risk of bias for the included studies and used the GRADE approach to produce a 'Summary of findings' table which included our prespecified main outcomes of interest.

MAIN RESULTS

Searching identified 113 records. We obtained the full text of 48 of these records for closer inspection. Sixteen trials, randomising a total of 919 participants are included. The majority of trials included adults with schizophrenia or similar illness who were inpatients, and while they were poorly characterised, most appeared to include patients with a chronic presentation. The intervention NRI in nine of the 16 trials was reboxetine, with atomoxetine and viloxazine used in the remaining trials. 14 trials compared NRIs with placebo. Only two trials provided data to compare NRIs against an active control and both compared reboxetine to citalopram but at 4 weeks and 24 weeks respectively so they could not be combined in a meta-analysis.One trial was described as 'open' and we considered it to be at high risk of bias for randomisation and blinding, three trials were at high risk of bias for attrition, six for reporting, and two for other sources of bias. Our main outcomes of interest were significant response or improvement in positive/negative mental state, global state and cognitive functioning, average cognitive functioning scores, significant response or improvement in quality of life and incidence of nausea. All data for main outcomes were short term.NRIs versus placeboMental state results showed significantly greater rates of improvement in negative symptoms scores (1 RCT, n = 50; RR 3.17, 95% CI 1.52 to 6.58; very low quality evidence) with NRIs on the PANSS negative. No data were reported for significant response or improvement in positive symptoms, but average endpoint PANSS positive scores were available and showed no difference between NRIs and placebo (5 RCTs, n = 294; MD -0.16, 95% CI -0.96 to 0.63; low-quality evidence). Improvement in clinical global status was similar between groups (1 RCT, n = 28; RR 0.99, 95% CI 0.45 to 2.20; very low quality evidence). Significant response or improvement in cognitive functioning data were not reported. Average composite cognitive scores showed no difference between NRIs and placebo (4 RCTs, n = 180; SMD 0.04, 95% CI -0.28 to 0.36; low-quality evidence). Significant response or improvement in quality of life data were not reported, however average endpoint scores from the GQOLI-74 were reported. Those receiving NRIs had better quality of life scores compared to placebo (1 RCT, n = 114; MD 9.36, 95% CI 7.89 to 10.83; very low quality evidence). All-cause withdrawals did not differ between the treatment groups (8 RCTs, n = 401, RR 0.94 95% CI 0.63 to 1.39; moderate-quality evidence). Rates of nausea were not greater with NRIs (3 RCTs, n = 176; RR 0.49, 95% CI 0.10 to 2.41; low-quality evidence).

AUTHORS' CONCLUSIONS

Our results provide tentative very low quality evidence that compared to placebo, NRIs (specifically reboxetine) may have a benefit on the negative symptoms of schizophrenia. Limited evidence also suggests that NRIs have no effect on the positive symptoms of schizophrenia or cognitive functioning. NRIs appear generally well tolerated with no real differences in adverse effects such as nausea noted between NRIs and placebo. However, these results are based on short-term follow-up and are poor quality - there is need for more good-quality evidence. A large RCT of reboxetine over a longer period of time, focusing specifically on negative and cognitive symptoms as well as more detailed and comprehensive reporting of outcomes, including adverse events, is required.

Cigarette smoking and schizophrenia

It has been recognised for many years that patients with psychiatric illnesses, especially schizophrenia, smoke to excess. However, recently there has been a resurgence of interest in the high prevalence of nicotine addiction in patients with schizophrenia. It has become increasingly clear that heavy cigarette smoking is intimately associated with the schizophrenic illness and that this may have implications for the underlying neurobiology of schizophrenia.

Changes in BMI in hospitalized patients during treatment with antipsychotics, depending on gender and other factors

OBJECTIVE

To investigate the differences in body mass index (BMI) changes between men and women during hospitalization.

METHODS

The retrospective study monitored demographic and clinical data of 462 schizophrenic patients hospitalized 737 times between 2006 and 2011. BMI analysis was performed on patients on antipsychotic medication hospitalized longer than four days.

RESULTS

Patients with an initial BMI < 25 gained more weight than patients with a BMI > 25 (3.94% vs. 0.23%, men 4.02% vs. 0.69%, women 3.79% vs. -0.52%, always p < 0.001). Greater BMI gains were reported during the first hospitalization than during subsequent ones (3.94% vs. 1.66%, men 3.97% vs. 1.98%, women 3.88% vs. 1.18%, always p < 0.001). The comparison between men and women showed a higher increase in BMI in men 2.36% vs. 1.54%, p = 0.022. Men also gained significantly more weight than women on polytherapy (+2.55% vs. +1.37%) and during subsequent hospitalizations (1.98% vs. 1.18%). For treatment with various atypical antipsychotics (AP), no significant differences were found in weight changes between men and women; during treatment using a combination of multi-receptor AP and metabolically neutral aripiprazole, a significant increase of BMI occurred in men, but not in women (p = 0.018).

CONCLUSIONS

Men appear to be more prone to weight gain than women.

How gender affects the pharmacotherapeutic approach to treating psychosis - a systematic review

INTRODUCTION

The effectiveness, effective dosages and side effect profiles of antipsychotic medication differ significantly between the sexes. Areas covered: We present a systematic review of gender-differences in the treatment of psychosis focusing on randomized, controlled trials and meta-analyses. Expert opinion: Despite many years of research, the database on gender-differences affecting the pharmacotherapeutic approach to treating psychosis is insufficient. Currently, the US National Institute of Health encouraged the enrolment of female participants in federally supported phase III clinical trials to increase the data available of female patients. Emerging evidence points to a superior antipsychotic response in women, with men requiring higher dosages. In general, women metabolize drugs differently, resulting in side effects occuring more frequently when compared to men. In any case, women require electrocardiograms or bone density scans as well as diabetes and cardiovascular workups when treated with antipsychotics. Dose adjustments during the menstrual cycle (e.g. to raise antipsychotic doses premenstrually) should be considered. First-generation antipsychotics, drugs that are known to prolong QTc interval and increase prolactin levels should be avoided in postmenopausal female patients. Furthermore, the effects of antipsychotics during pregnancy and breastfeeding have been investigated insufficiently, and more research is urgently needed.

The effect of nicotine dependence on psychopathology in patients with schizophrenia

Introduction. Our study aims to determine the prevalence of nicotine dependence and investigate the effect of nicotine dependence on psychopathology among schizophrenia patients. Methods. A cross-sectional study was carried out in an outpatient psychiatric clinic at a general hospital in Malaysia. 180 recruited subjects were administered the Malay version of Mini International Neuropsychiatric Interview (MINI), the Positive and Negative Symptom Scale (PANSS), and the Malay version of Fagerstrom Test for Nicotine Dependence (FTND-M) questionnaires. Results. The prevalence of nicotine dependence among the subjects was 38.1% (n = 69) and they were mainly composed of male gender, Malay ethnicity, being treated with atypical antipsychotics, and taking other illicit drugs or alcohol. Subjects with severe nicotine dependence scored less in the negative subscale of PANSS compared with the nonsmokers (P = 0.011). On performing the hierarchy multiple regressions, dependence status still significantly predicted negative scores after adjusting the confounders (t = −2.87, P = 0.005). Conclusion. The rate of nicotine use disorder among schizophrenia patients in this study is higher than that of the general population in Malaysia. The significant association between nicotine dependence and negative psychopathology symptoms will help the healthcare practitioners in their management of nicotine dependence among schizophrenia patients.

Prevalence and correlates of cigarette smoking among patients with schizophrenia in southeast Nigeria

OBJECTIVE

To determine the prevalence of cigarette smoking among patients with schizophrenia and to explore their sociodemographic and clinical characteristics.

METHOD

A cross-sectional descriptive study of 367 patients with schizophrenia. Instruments administered included sociodemographic questionnaire, Present State Examination: schizophrenia section to confirm schizophrenia diagnosis and Present State Examination: tobacco section to those that smoked.

RESULTS

A total of 189 females (51.5%) and 178 (48.5%) males were studied. The mean age of the participants was 34.1 ± 9.94 years. Two hundred and forty-one (65.7%) had never being married. Two hundred and three (55.3%) had secondary school education. A lifetime prevalence of 25.9% and a current smoking rate of 20.4% were reported. Ninety five (53.4%) of the males had smoked at least once in their lifetime. None of the females smoked. Among those that smoked, being unmarried (ϰ² = 6.51, P < 0.01) and unemployed (ϰ² = 5.11, P < 0.02) were associated with prescription of high doses of antipsychotics. Of those that smoked, the managing psychiatrist identified or documented only twenty-five (26.3%) of them (kappa = 0.80, P < 0.00).

CONCLUSION

The rate of smoking in Nigerian patients with schizophrenia is considerably less than is reported for their Western counterparts.

Effects of cigarette smoking on metabolism and effectiveness of systemic therapy for lung cancer

INTRODUCTION

Cigarette smoke associated polycyclic aromatic hydrocarbons can induce key drug-metabolizing enzymes of cytochrome P450 and isoforms of the glucuronyl transferases families. These enzymes metabolize several systemic therapies for lung cancer. Induction of these enzymes may lead to accelerated clearance with resultant impact on systemic therapy efficacy and toxicity in smokers compared with nonsmokers. This article reviews published literature regarding the influence of smoking as it relates to alteration of metabolism of systemic therapy in lung cancer.

METHODS

A structured search of the National Library of Medicine's PubMed/MEDLINE identified relevant articles. Data were abstracted and analyzed to summarize the findings.

RESULTS

Studies that analyzed pharmacokinetic data were prospective. Smokers receiving erlotinib exhibited rapid clearance, requiring a higher dose to reach equivalent systemic exposure compared with nonsmokers. Smokers receiving irinotecan also demonstrated increased clearance and lower systemic exposure. There was no difference in clearance of paclitaxel or docetaxel in smokers. Chemotherapy-associated neutropenia was worse in nonsmokers compared with smokers in patients treated with paclitaxel, docetaxel, irinotecan, and gemcitabine.

CONCLUSIONS

Systemic therapy for lung cancer has a narrow therapeutic index such that small changes in plasma concentrations or exposure in smokers may result in suboptimal therapy and poor outcomes. Smoking cessation must be emphasized at each clinical visit. However, prospective trials should take into consideration the effects of smoking history on drug pharmacokinetics and efficacy. The metabolizing enzyme phenotype in smokers may require individualized dose algorithms for specific agents.

Socio-demographic and clinical characteristics of heavy and non-heavy smokers among schizophrenia inpatients in a Chinese Han population

OBJECTIVE

Despite higher smoking rates in schizophrenia, few studies have explored the clinical-demographic correlates of different amounts of smoking exposure. Little is known about the association between smoking severity and clinical phenotypes in Chinese patients with schizophrenia.

MATERIALS AND METHODS

We investigated differences between heavy (≥1 pack/day) and non-heavy (<1 pack/day) smoking in 550 male inpatients with schizophrenia using clinician-administered questionnaires and the Fagerstrom Test for Nicotine Dependence. They also were rated on the Positive and Negative Symptom Scale (PANSS), the Simpson and Angus Extrapyramidal Symptom Rating Scale (SAES), and the Abnormal Involuntary Movement Scale (AIMS), as well as were assayed with laboratory tests and an electrocardiogram.

RESULTS

Heavy smoking prevalence was approximately 31 %. Compared to the non-heavy smokers, the heavy smokers were younger, more with paranoid subtype but less with disorganized subtype schizophrenia, smoked at an earlier age, fewer getting clozapine or all atypical antipsychotics together, and were taking larger doses of antipsychotic drugs. The heavy smokers scored significantly lower on the PANSS negative symptom subscore and total score, and also on the SAES and AIMS scores than the non-heavy smokers. In addition, heavy smokers displayed longer rate-corrected electrocardiographic QT intervals, but without any significant differences in other laboratory tests.

CONCLUSION

Our results suggest several clinical or demographic differences between the heavy and non-heavy smoking patients with schizophrenia in a Chinese population. Heavy smoking remains a general health risk for schizophrenia.

Use of cotinine urinalysis to verify self-reported tobacco use among male psychiatric out-patients

CONTEXT

There is a complex and significant correlation between respiratory disorders and psychiatric conditions. Reliability of self-reported tobacco use has been questioned in recent times.

AIMS

The current study aims at assessment of accuracy of self-reported tobacco use (both smoked and smokeless) among psychiatric out-patients.

SETTINGS AND DESIGN

We recruited 131 consecutive subjects from the out-patient psychiatry department of a tertiary care hospital.

MATERIALS AND METHODS

Male patients meeting the study criteria were approached for participation in the study. They were asked about their recent tobacco use history. Those reporting recent use were assessed for severity of dependence using Fagerstrom Test for Nicotine Dependence (FTND)-smoking and FTND-smokeless scales. Quantitative urine cotinine analysis was performed using the Enzyme Linked Immunesorbant Assay (ELISA) method. Based on this method, a (50 ng/ml) cut off score for urinary cotinine level for tobacco use was set.

STATISTICAL ANALYSIS USED

Concordance between the self-report of tobacco use and urinary cotinine level was assessed using the Cohen's kappa. Additionally, Pearson's correlation coefficient was used to examine the correlation between the FTND-smoking and FTND-smokeless scales and the urinary cotinine levels.

RESULTS

The values of Cohen's kappa suggest no significant concordance between the self-reported recent tobacco use and urinary cotinine levels for both smoking and smokeless tobacco forms. The discordance was present irrespective of a higher (550 ng/ml) or a lower (50 ng/ml) cut off score for a urinary cotinine level. Pearson's correlation coefficient failed to reveal any significant direct correlation between the FTND scores and urinary cotinine levels.

CONCLUSIONS

It is recommended to use biological markers such as urinary cotinine levels to corroborates the information provided by the patients.

Nicotine dependence and illness severity in schizophrenia

BACKGROUND

Reasons for the increased prevalence of cigarette smoking in schizophrenia are unclear. Studies assessing clinical symptoms have sampled heterogeneous populations, with discrepant findings.

AIMS

To examine the relationship between clinical features, social adjustment and nicotine dependence in a geographically defined population of people with schizophrenia.

METHOD

Cross-sectional clinical study of 131 people with schizophrenia in Nithsdale, Scotland.

RESULTS

Smokers were younger, mostly males and three times more likely to be unemployed. Those with severe nicotine dependence had greater scores on the positive subscale of the Positive and Negative Syndrome Scale (PANSS), and were prescribed higher doses of antipsychotic. Those with mild-moderate dependence had greater scores on the PANSS negative subscale. Greater symptom severity was associated with poorer social adjustment. Psychopathology and social adjustment were similar in quitters and never-smokers.

CONCLUSIONS

Our findings indicate an association between nicotine dependence, clinical symptoms and social adjustment in schizophrenia. Although causal links cannot be inferred, identifying the relationship between nicotine dependence and psychopathology may have some value in the management of smoking in schizophrenia. Further longitudinal studies are required to explore this relationship.

Cigarette smoking in male patients with chronic schizophrenia in a Chinese population: prevalence and relationship to clinical phenotypes

The high prevalence of smoking in schizophrenia of European background may be related to smoking's reducing clinical symptoms and medication side effects. Because smoking prevalence and its associations with clinical phenotypes are less well characterized in Chinese than European patients with schizophrenia, we assessed these smoking behaviors using clinician-administered questionnaires and the Fagerstrom Test for Nicotine Dependence (FTND) in 776 Chinese male schizophrenia and 560 control subjects. Patients also were rated on the Positive and Negative Symptom Scale (PANSS), the Simpson and Angus Extrapyramidal Symptom Rating Scale (SAES), and the Abnormal Involuntary Movement Scale (AIMS). We found that the schizophrenia patients had a higher lifetime incidence of smoking (79% vs 63%), were more likely to be heavy smokers (61% vs 31%), and had lower smoking cessation rates (4% vs 9%) (all p<0.0001) than controls. Among the schizophrenia patients smoking prevalence increased with age, with the largest difference from controls in the age cohort of 55-75 years: 75% vs 46% (p<0.0001). Among the schizophrenia smokers 73% started to smoke before the onset of their illness by an average of 7.6 years. The patients with schizophrenia who were current smokers scored significantly lower on the PANSS negative symptom subscore (p<0.005), and on the SAES symptom scale (p<0.04; Bonferroni corrected p>0.05) than the non-smoking patients. These results suggest that Chinese males with schizophrenia smoke more frequently than the general population. Further, smokers with schizophrenia may display fewer negative symptoms and possibly less parkinsonism than non-smokers with schizophrenia.

Tobacco smoking in Egyptian schizophrenia patients with and without obsessive-compulsive symptoms

BACKGROUND

Nicotine dependence is common in schizophrenia patients but rare in patients with obsessive-compulsive disorder. Little is known, however, about smoking in schizophrenia patients with obsessive-compulsive symptoms (OCS) especially in a developing country, such as Egypt, that has the highest rate of tobacco consumption in the Middle East and North Africa.

OBJECTIVES

To test a hypothesis that nicotine dependence in schizophrenia patients with-OCS is lower than in those without-OCS.

RESULTS

Out of 87 consecutive schizophrenia patients attending a psychiatric out-patients clinic in Egypt, 34 patients (39%) had significant OCS, and a smoking rate (85.3%) not significantly lower than that of patients without-OCS (90.6%). Patients were reclassified by their Fagerström's scores into 3 groups of nicotine dependence: mild (37 patients), high (21 patients) and very high (29 patients). There were no differences between these groups in terms of YBOCS scores (F=0.324; p=0.724). When comparing PANSS scores of patients, with and without-OCS, those of the former group were higher on the positive symptoms (mean=24.2 versus 20.8; p=0.002), and anxiety/depression (mean=10.8 versus 10.1; p=0.03) but lower on the negative symptoms (mean=15.0 versus 19.4; p=0.000), disorganized thoughts (mean=14.5 versus 17.5; p=0.002), and uncontrolled hostility/excitement) (mean=7.5 versus 9.5; p=0.002). However, there was no significant between-group difference in the total PANSS scores.

CONCLUSIONS

The high and equal rates of smoking in patients with-, and without-OCS, and the lack of difference between YBOCS scores of mild, high and very high nicotine dependence groups undermined our initial hypothesis that nicotine dependence in schizophrenia patients with-OCS is lower than in those without them. Nevertheless, the finding of a distinctive PANSS scores, may support a suggestion that OCS in schizophrenia represent a distinct subtype or dimension.

A 12-week double-blind, placebo-controlled study of bupropion sr added to high-dose dual nicotine replacement therapy for smoking cessation or reduction in schizophrenia

The objective of this study was to examine whether there is a benefit of adding bupropion SR to high-dose combination nicotine replacement therapy (NRT) and weekly group cognitive behavioral therapy (CBT) for smoking reduction or cessation in schizophrenia. Fifty-one adult smokers with schizophrenia were randomly assigned to a 12-week trial of bupropion SR 300 mg/d or placebo added to transdermal nicotine patch, nicotine polacrilex gum, and CBT. The treatment goal was smoking cessation. The primary outcome measure was biochemically confirmed 7-day point-prevalence of 50% to 100% smoking reduction at week 12. Secondary outcomes were biochemically confirmed tobacco abstinence and change from baseline in expired air carbon monoxide (CO) and psychiatric symptoms. Subjects on bupropion + NRT had a greater rate of 50% to 100% smoking reduction at weeks 12 (60% vs. 31%; P = 0.036) and 24, a lower expired air CO in the treatment and follow-up periods, (F = 13.8; P < 0.001) and a greater continuous abstinence rate at week 8, before NRT taper, (52% vs. 19%; P = 0.014). However, relapse rates in subjects on bupropion + dual NRT were 31% during NRT taper (weeks 8-12) and 77% at the 12-month follow-up. Abstinence rates did not differ by treatment group at weeks 12 (36% vs. 19%), 24 (20% vs. 8%), or 52 (12% vs. 8%). Because abstinence rates were high during treatment with combination pharmacotherapy and relapse rates were very high during taper and after discontinuation of treatment, study of longer term treatment with combination pharmacotherapy and CBT for sustained abstinence is warranted in those who attain initial abstinence with this intervention.

Does smoking reduce akathisia? Testing a narrow version of the self-medication hypothesis

BACKGROUND

The self-medication hypothesis proposes that schizophrenia patients smoke to decrease their schizophrenia symptoms or antipsychotic side effects, but they usually start smoking before their illness and heavy smoking is not consistently associated with fewer symptoms or side effects. A narrow version of the self-medication hypothesis, heavy smoking reduces akathisia, is explored.

METHOD

The sample included 250 outpatients with DSM-IV schizophrenia assessed with the Positive and Negative Syndrome Scale (PANSS) and the Barnes Akathisia Scale. Prevalences were 69% (173/250) for smoking, 39% (98/250) for heavy smoking (> or =30 cigarettes/day), 7% (17/250) for akathisia (Barnes Global score>1), 14% (35/250) for a broader akathisia definition (Barnes Global score>0) and 20% for excited symptoms (>1 on the PANSS factor score).

RESULTS

Heavy smoking was not associated with akathisia (41% of patients with akathisia were heavy smokers versus 39% of patients without akathisia; chi2=0.3, df=1, p=0.86), even after correcting for confounding factors and/or using a broader akathisia definition. Heavy smoking was associated with excited schizophrenia symptoms (possibly reflecting agitation). Particularly in patients taking lower doses of typical antipsychotics, excited symptoms, with or without akathisia, were strongly associated with heavy smoking and appear to interact with patients' reports of smoking's calming effect as the main reason for smoking.

CONCLUSION

The self-medication hypothesis does not explain increased smoking and heavy smoking in schizophrenia. Moreover, heavy smoking may be associated with more disturbed brain homeostatic mechanisms. Prospective studies need to explore whether temporary increases in cigarette smoking may be associated with periods of higher agitation, with or without akathisia.

Nicotine use in schizophrenia: the self medication hypotheses

The behavioural and cognitive effects of nicotine in schizophrenia have received much interest in recent years. The rate of smoking in patients with schizophrenia is estimated to be two- to four-fold the rate seen in the general population. Furthermore such patients favour stronger cigarettes and may also extract more nicotine from their cigarettes than other smokers. The question has been raised whether the widespread smoking behaviour seen in this patient group is in fact a manifestation of a common underlying physiology, and that these patients smoke in an attempt to self-medicate. We present an overview of the explanations for elevated rates of smoking in schizophrenia, with particular emphasis on the theories relating this behaviour to sensory gating and cognitive deficits in this disorder that have been viewed as major support for the self-medication hypotheses.

Gender and the use of neuroleptics in schizophrenia

INTRODUCTION

The oestrogen hypothesis proposes that the lower need for neuroleptic drugs in female schizophrenia patients is caused by the antidopaminergic effect of oestrogens, and that when oestrogen production decreases at menopause, the need for neuroleptic drugs increases in female schizophrenia patients.

SUBJECTS AND METHOD

The oestrogen hypothesis was tested in a sample of 4338 schizophrenia patients (DSM III R), who were discharged from hospital and followed up for 3 years. Prescribed daily doses of neuroleptics (DDN) were recorded and converted to chlorpromazine equivalents.

RESULTS

Males had higher DDN than females. When the age at first admission (AFA) was controlled, DDNs were higher in males than in females in all age groups. In addition to AFA, DDNs were associated with duration of illness (DUI), education, smoking and clinical status as well as with concurrently prescribed antidepressants, anti-manics, sedatives and hypnotics, but these factors did not explain the gender differences in DDN.

CONCLUSIONS

The results did not support the original oestrogen hypothesis. It is proposed that testosterone secretion may explain why male schizophrenia patients are prescribed higher DDNs than female patients. Ageing processes in the central nervous system (CNS) may explain why DDNs decrease after middle age in both genders.

Effects of smoking and cytochrome P450 2D6*10 allele on the plasma haloperidol concentration/dose ratio

OBJECTIVE

This study was carried out to evaluate the influence of CYP2D6 polymorphism and smoking on the plasma clearance of haloperidol (HAL) levels, accounting for the antipsychotic dose, body weight, and coadministration of other drugs.

METHODS

Subjects were 110 Japanese patients (66 male, 44 female) diagnosed with schizophrenia, dementia, or mood disorder and treated orally with HAL. Venous blood was obtained from each patient to determine the HAL concentration/dose (C/D) ratio (plasma concentration of HAL divided by the daily dose of HAL per body weight) and for CYP2D6 genotyping.

RESULTS

There was no significant difference in the HAL C/D ratio between nonsmokers and smokers. In patients with a non-2D6*10 homozygous genotype, smokers had a significantly lower HAL C/D ratio than nonsmokers, whereas smokers with a 2D6*10 homozygous genotype had a significantly higher HAL C/D ratio than those with a non-2D6*10 homozygous genotype.

CONCLUSION

Our results suggest that the effect of smoking on the HAL C/D ratio depends on the CYP2D6*10 genotype.

Susceptibility to neuroleptic-induced parkinsonism--age and increased substantia nigra echogenicity as putative risk factors

OBJECTIVE

Patients treated by neuroleptics often develop neuroleptic-induced parkinsonism (NIP) to a varying extent. The reasons for this are discussed controversially in the literature. Previous transcranial sonography (TCS) findings of the substantia nigra (SN) in patients with idiopathic Parkinson's disease suggest a correlation of echogenicity with nigrostriatal dysfunction.

METHOD

One hundred psychiatric patients receiving neuroleptics were included. They underwent clinical examination for NIP (Simpson and Angus-scale) and, independently, TCS of the SN. History of smoking habits and medication were taken from the patient's chart.

RESULTS

We found a significant positive association of the prevalence of NIP with age (P < 0.01) and the echogenic area of the SN (P < 0.05). Neither type nor dosage of the neuroleptics was found to have any significant impact on the occurrence of NIP. Smokers displayed lower prevalence of NIP (P < 0.05) and lower EPS scores (P < 0.01).

CONCLUSIONS

These findings suggest that age and increased size of SN echogenicity are possible risk factors for NIP. In contrast, smoking seems to have a certain protecting effect.

Nithsdale Schizophrenia Surveys 24: sexual dysfunction. Case-control study

BACKGROUND

That sexual dysfunction occurs in schizophrenia is not in doubt. Previous studies have had weaknesses such as the use of selected populations or the absence of a control group.

AIMS

To measure rates of sexual dysfunction in people with schizophrenia compared with the general population.

METHOD

Sexual dysfunction was assessed by a self-completed gender-specific questionnaire. Ninety-eight (73%) of 135 persons with schizophrenia and 81 (71%) of 114 persons recruited as controls returned the questionnaire.

RESULTS

At least one sexual dysfunction was reported by 82% of men and 96% of women with schizophrenia. Male patients reported less desire for sex, were less likely to achieve and maintain an erection, were more likely to ejaculate more quickly and were less satisfied with the intensity of their orgasms. Female patients reported less enjoyment than the control group. Sexual dysfunction in female patients was associated with negative schizophrenic symptoms and general psychopathology. There was no association between sexual dysfunction and type of antipsychotic medication.

CONCLUSIONS

People with schizophrenia report much higher rates of sexual dysfunction than do the general population. Men and women with schizophrenia have a different pattern of sexual dysfunction.

Smoking in patients receiving psychotropic medications: a pharmacokinetic perspective

Many psychiatric patients smoke, and are believed to be heavier smokers than those without psychiatric disorders. Cigarette smoking is one of the environmental factors that contributes to interindividual variations in response to an administered drug. Polycyclic aromatic hydrocarbons (PAHs) present in cigarette smoke induce hepatic aryl hydrocarbon hydroxylases, thereby increasing metabolic clearance of drugs that are substrates for these enzymes. PAHs have been shown to induce 3 hepatic cytochrome P450 (CYP) isozymes, primarily CYP1A1, 1A2 and 2E1. Drug therapy can also be affected pharmacodynamically by nicotine. The most common effect of smoking on drug disposition in humans is an increase in biotransformation rate, consistent with induction of drug-metabolising enzymes. Induction of hepatic enzymes has been shown to increase the metabolism and to decrease the plasma concentrations of imipramine, clomipramine, fluvoxamine and trazodone. The effect of smoking on the plasma concentrations of amitriptyline and nortriptyline is variable. Amfebutamone (bupropion) does not appear to be affected by cigarette smoking. Smoking is associated with increased clearance of tiotixene, fluphenazine, haloperidol and olanzapine. Plasma concentrations of chlorpromazine and clozapine are reduced by cigarette smoking. Clinically, reduced drowsiness in smokers receiving chlorpromazine, and benzodiazepines, compared with nonsmokers has been reported. Increased clearance of the benzodiazepines alprazolam, lorazepam, oxazepam, diazepam and demethyl-diazepam is found in cigarette smokers, whereas chlordiazepoxide does not appear to be affected by smoking. Carbamazepine appears to be minimally affected by cigarette smoke, perhaps because hepatic enzymes are already stimulated by its own autoinductive properties. Cigarette smoking can affect the pharmacokinetic and pharmacodynamic properties of many psychotropic drugs. Clinicians should consider smoking as an important factor in the disposition of these drugs.

Effects of smoking during antipsychotic withdrawal in patients with chronic schizophrenia

A number of studies have shown that patients with schizophrenia smoke more than other psychiatric patients and more than the general population. Also, medicated schizophrenics who smoke present more positive symptoms of schizophrenia than non-smokers. The objective of the present study was to assess the effect of smoking on ratings of psychopathology for 30 days following discontinuation of antipsychotic medication. The subjects were 101 treatment-resistant patients with schizophrenia who had been admitted to the inpatient service of Neuroscience Research Hospital (NRH), National Institute of Mental Health, between 1982 and 1994 to undergo studies involving discontinuation of antipsychotic medication. Patients were rated independently on a daily basis on the 22-item Psychiatric Symptom Assessment Scale (PSAS), an extended version of the Brief Psychiatric Rating Scale (BPRS). At baseline, ratings for Verbal Positive, Paranoia and Loss of Function were higher in smokers (n=65) than non-smokers (n=36), but a statistically significant difference was observed only for the Verbal Positive cluster. Analysis by gender revealed that male non-smokers had the lowest psychopathology ratings at baseline. There were no differences in Anxiety/depression, Behavior Positive, Deficit Symptoms or Mannerisms (a measure for abnormal involuntary movements). Following medication discontinuation, repeated-measure analysis demonstrated a 'time' effect for all the variables studied and a 'group' (smokers vs. non-smokers) effect for Verbal Positive, Paranoia, and Loss of Function. Post-hoc comparisons at individual time points showed significantly higher ratings for smokers at week 1 for Paranoia. No differences were observed at later time points. In conclusion, at baseline, smokers had more positive symptoms and were apparently more functionally impaired than non-smokers. This difference was no longer evident after a 30 day medication discontinuation period.

Addiction and schizophrenia

Epidemiologic studies in the general population and those based on the clinical assessment of schizophrenic populations have revealed a high degree of overlap between schizophrenia and addictive disorders. The abuse of psychoactive substances (including alcohol) throughout life is so frequent (50%) that the possibility of a specific link inevitably arises. Various hypotheses have been suggested to explain the high co-morbidity between schizophrenia and addiction: 1) The social-environmental hypothesis has been developed but studies have provided poor evidence to validate it. 2) The possible shared biological vulnerability between schizophrenia and addictions led researchers to explore common genetic determinants and study the involvement of the dopaminergic and opioid systems in the aetiology of both schizophrenia and the abuse of and dependence on psychoactive drugs. 3) Finally, the theory of self-medication suggests that schizophrenics may be attempting to counter the deficit linked to their disorders by using the substances they take or their dependency-type behaviour to cope with their emotional problems. The clinical profile of schizophrenic addicts does seem to display some distinctive features, such as the high level of depressive co-morbidity, very high nicotine and alcohol dependence, with a very poor prognosis. These patients are difficult to manage; the possibility of pharmacologic interactions between the substances they are taking and neuroleptic medication calls for prudence, and their compliance is also poor. Addictive disorders in schizophrenics are currently a topic of active research intended to lead to identifying specific treatments. The early identification of addictive disorders in schizophrenics should make it possible to limit their development and improve the prognosis.

Smoking habits, current symptoms, and premorbid characteristics of schizophrenic patients in Nithsdale, Scotland

OBJECTIVE

Previous studies of smoking habits of schizophrenic patients have found rates as high as 88%. The authors report the smoking habits of all known schizophrenic patients within a discrete geographical area and compare them with the smoking habits of a general population sample.

METHOD

All known schizophrenic patients in Nithsdale in South-West Scotland (N = 168) were invited to complete a questionnaire on smoking habits. Also assessed were mental state, drug-related side effects, and premorbid childhood personality and social adjustment.

RESULTS

One hundred thirty-five of the 168 patients returned the questionnaires. The rate of smoking among the patients was 58% (N = 78), compared with 28% in the general population. Sixty-eight percent of the patients who smoked (N = 53) had 25 or more cigarettes per day. The mean age at starting smoking was 17 years in both patients and normal subjects. Ninety percent of the patients who smoked (N = 70) started smoking before the onset of schizophrenia. Patients who smoked were younger than nonsmokers, and more of them were male. They had had more hospitalizations, and more were in contact with psychiatric services. More were receiving intramuscular antipsychotic medication. Smokers had poorer childhood social adjustment. Among the female patients, there was a positive correlation between age at starting smoking and age at onset of schizophrenia.

CONCLUSIONS

The rate of smoking and level of nicotine addiction are greater in schizophrenic patients than in the general population. Smoking may be a marker for the neurodevelopmental form of the illness and may be another environmental risk factor for schizophrenia in vulnerable individuals.

Smoking attitudes, beliefs, and readiness to change among acute and long term care inpatients with psychiatric diagnoses

The present study represents an initial assessment of barriers and motives for quitting, health risk knowledge, and readiness to change in a hospitalized acute and long term care population with psychiatric diagnoses, and dual diagnoses of substance abuse and psychiatric disorders. Ninety-two patients residing in admissions, long term care, and mentally impaired/chemically addicted (MICA) units of a VA Medical Center were interviewed by nursing staff. Among the 78% of patients who smoke (smokers), 68% believed smoking was harmful and quitting would benefit their health. The majority of smokers were in Precontemplation (53%) or Contemplation (24%). Smokers in the MICA unit were more similar to the general population in smoking related beliefs and were more likely than other smokers to be in Preparation. These results indicate a need for educational and motivational enhancement interventions for the majority of smokers hospitalized for psychiatric disorders.

Smoking and cognitive deficits in schizophrenia: a pilot study

The cross-sectional study assessed the associations among smoking status, number of cigarettes smoked per day, and psychiatric symptoms in 88 chronic schizophrenic outpatients with a stable psychic condition. Among the 49 smokers, the number of cigarettes smoked per day was associated with the severity of cognitive symptoms of the Positive and Negative Syndrome Scale. The authors suggest that smoking may alleviate cognitive deficits in schizophrenia by increasing dopaminergic neurotransmission in the prefrontal areas of the brain.