Shorter interpuff interval is associated with higher nicotine intake in smokers with schizophrenia

Caffeine levels and dietary intake in smokers with schizophrenia and bipolar disorder

Caffeine is one of the most widely used psychoactive drugs in the United States. High rates of caffeine use have been observed in adult smokers as well as those with serious mental illness. The current secondary analysis aimed to extend previous findings demonstrating high caffeine intake in schizophrenia by examining dietary intake of caffeine and serum caffeine levels in outpatient smokers with schizophrenia (SCZ), bipolar disorder (BP) and control smokers with no psychiatric diagnoses (CON). Two hundred forty-eight adult smokers (SCZ=80; BP=80; CON=88) were included in the current study. Adult smokers with schizophrenia, bipolar disorder, and no psychiatric diagnoses were 40.85 (SD = 11.90) years old on average and all participants were current smokers (∼20 cigarettes per day). Twenty-four hour self-reported caffeine intake (in mg) was highest among individuals with bipolar disorder (median=195.3), followed by adults with schizophrenia (median=155.0) and controls (median=131.7). Participants with bipolar disorder also had the highest serum caffeine levels (in ng/ml; median=1725), followed by those with schizophrenia (median=1194) and controls (median=613.2).  These results provide additional evidence of high caffeine intake among adults with schizophrenia and extend findings by identifying even higher rates of caffeine use in those with bipolar disorder. The current study suggests that caffeine intake is higher among subgroups of patients with serious mental illness.

Study on the daily Ad Libitum smoking habits of active Korean smokers and their effect on urinary smoking exposure and impact biomarkers

INTRODUCTION

Understanding interactions of smoking topography with biomarkers of exposure to tobacco is essential for accurate smoking risk assessments.

METHODS

In this study, the smoking topography and the levels of tobacco smoke exposure urinary biomarkers of a sample of active Korean smokers were quantified and measured. The results were used to investigate the effect of daily activities and smoking time on the smoking topography. Moreover, correlations between the smoking topography parameters and biomarkers were assessed.

RESULTS

No significant effect of either the daily activities or time on the smoking topography of the subjects were observed. Synchronic correlations of the cigarette consumption per day (CPD) and the average flow per puff with both urinary cotinine and trans-3'-hydroxycotinine were significant. For the urinary nicotine metabolites, the peak levels appeared when the CPD was over 19 cigarettes per day and the average puff velocity was between 35 and 45 ml/s. Nevertheless, when the average flow was over 60 ml/s, the levels of cotinine and trans-3'-hydroxycotinine significantly dropped.

CONCLUSIONS

The findings of this study may be beneficial for further smoking risk assessments with contributions of both the smoking topography and biomarkers to provide current smokers with applicable cession programs.Clinical significanceSmoking habits and levels of urinary biomarkers of Korean smokers are investigated.People with a higher dependency on nicotine smoke cigarettes with slower puffs.Effects of daily activities or time on smoking topography were not significant.Correlations between smoking topography and urinary biomarkers were significant.Peak biomarker levels were observed under certain smoking topography conditions.

Comparison of smoking cessation program registration, participation, smoking cessation medication utilization and abstinence rates between smokers with and without schizophrenia, schizo-affective disorder or bipolar disorder

INTRODUCTION

People with serious mental illness (SMI) are three times more likely to smoke and be heavy smokers than smokers without SMI. Counseling combined with smoking cessation medication (SCM) is the recommended treatment. However until 2017, SCM prescription for SMI smokers was discouraged (FDA black box warning). This study compared use of smoking cessation programs (SCP) and SCM between smokers with and without SMI.

METHODS

Data regarding SCP and SCM use were extracted from the database of a large HMO that offers free Group and telephone SCP. SCP registration, participation, completion and abstinence rates between July 2013 and December 2019 were compared between smokers with and without SMI, controlling for demographic and health variables.

RESULTS

48,000 smokers registered for a SCP during the study period. Smokers with SMI were 1.8 times more likely to register for a SCP than smokers without SMI. Smokers without SMI were, however, 1.2 times more likely to start the SCP, 1.5 times more likely to complete the SCP and 1.6 times more likely to have quit by the end of the program. The strongest factors predicting abstinence were SCP completion and SCM use. Smokers with SMI were less likely to purchase SCM, although their purchase rate increased after the black box warning was lifted.

CONCLUSIONS

Smoking cessation programs and SCM use should be encouraged in the SMI population. Providing support during the quit attempt and adapting SCP to the needs of smokers with SMI, combined with SCM prescription promotion, should improve abstinence.

IMPLICATIONS

Smokers with serious mental illness (SMI) were more likely to seek professional help to quit smoking than non-SMI smokers, with over 30% achieving abstinence, discrediting healthcare professional beliefs that SMI smokers don't want to and cannot quit. Smoking cessation program (SCP) completion and smoking cessation medication (SCM) utilization were the strongest predictors of abstinence. SMI smokers were more likely to drop out of SCPs and less likely to use SCMs. Providing support during the quit attempt and adapting SCPs to the needs of smokers with SMI, combined with SCM prescription promotion, should improve abstinence.

A Single-Arm, Open-Label, Pilot, and Feasibility Study of a High Nicotine Strength E-Cigarette Intervention for Smoking Cessation or Reduction for People With Schizophrenia Spectrum Disorders Who Smoke Cigarettes

Introduction

An estimated 60%–90% of people with schizophrenia smoke, compared with 15%–24% of the general population, exacerbating the already high morbidity and mortality rates observed in this population.

Aims and Methods

This study aimed to assess the feasibility of using a new-generation high strength nicotine e-cigarette to modify smoking behavior in individuals with schizophrenia spectrum disorders who smoke cigarettes. A single-arm pilot study was conducted with 40 adults with schizophrenia spectrum disorders who smoked and did not intend to reduce or quit smoking. Participants were given a 12-week supply of a JUUL e-cigarette loaded with a 5% nicotine pod. The primary outcome was smoking cessation at week 12. Additional outcomes included: smoking reduction, continuous abstinence at week 24, adoption rate, adherence to the e-cigarette, feasibility, acceptability, and subjective effects.

Results

Sixteen (40%) participants quit by the end of 12 weeks. For the whole sample, we observed an overall, sustained 50% reduction in smoking or smoking abstinence in 37/40 (92.5%) of participants and an overall 75% reduction in median cigarettes per day from 25 to six was observed by the end of the 12 weeks (p < .001).

Conclusions

A high strength nicotine e-cigarette has the potential to help people with schizophrenia spectrum disorders to quit or reduce smoking. Further research with a larger sample and a comparator group is needed. The results provide useful information and direction to augment the existing body of knowledge on smoking cessation for people with schizophrenia spectrum disorders.

Implications

Considering that most people with schizophrenia spectrum disorders continue smoking, alternative and efficient interventions to reduce or prevent morbidity and mortality are urgently needed. This study showed that adults who smoke and were not motivated to quit, when provided a new-generation e-cigarette with high nicotine content, demonstrated substantially decreased cigarette consumption without causing significant side effects. Although not specifically measured in this study, nicotine absorption in new-generation devices has been shown to be consistently superior compared with the first generation of e-cigarette devices, and this may help explain the lower quit rates in studies using earlier generation devices.

Management of Cardiovascular Health in People with Severe Mental Disorders

PURPOSE OF REVIEW

To review evidence regarding the association between bipolar disorder and schizophrenia, henceforth referred to as severe mental disorders (SMD), and cardiovascular morbidity and mortality, its mechanisms, and the interventions to reduce this burden.

RECENT FINDINGS

Much of the loss in life expectancy in people with SMD remains driven by cardiovascular mortality. Antipsychotics and mood stabilizers are associated with negative cardio-metabolic outcomes, but large inter-individual differences are observed, and not treating SMD might be associated with even greater cardiovascular mortality. Classical modifiable cardiovascular risk factors remained inadequately screened and, once identified, too seldom treated in people with SMD. After a myocardial infarction, aggressive tertiary prevention may be as effective in people with SMD as in the general population but is less prescribed. Reduced healthcare quality and increased prevalence of cardiovascular risk factors may not fully explain the excess cardiovascular mortality associated with SMDs, which themselves should be considered risk factors in risk calculators. Hazardous health behaviors, the cardio-metabolic adverse effects of medications, and a reduced access to quality healthcare remain priority targets for intervention.

Biopsychosocial mechanisms associated with tobacco use in smokers with and without serious mental illness

Smokers with serious mental illness (SMI) are less responsive to cessation treatments than those without SMI. In this study, we compared smokers with and without SMI on validated measures of biological and psychosocial factors associated with tobacco use. Smokers with (n = 58) and without SMI (n = 83) who were enrolled in parallel clinical trials were compared on measures of carbon monoxide (CO) exposure, nicotine exposure, tobacco-specific nitrosamine exposure, craving, smoking motives, affect, perceived stress, environmental exposure to smoke/smokers, respiratory symptoms, tobacco-related health risk perceptions, and whether they had received recent advice to quit smoking from a health care provider. Data were collected between 2013 and 2017 in Providence, Rhode Island, USA. Samples were compared using independent-sample t-tests and chi-squared tests. Smokers with SMI had higher CO, nicotine, and tobacco-specific nitrosamine exposure levels, greater cigarette dependence, higher craving, and higher scores on eight out of eleven smoking motives (p's < 0.05). Smokers with SMI reported more severe respiratory symptoms but lower perceived health risks of tobacco (p's < 0.05). These smokers were more likely to report having received advice to quit from a medical provider in the past 6 weeks (p < 0.05). Affect, stress, and exposure to smoke/smokers did not differ across samples. Our findings advance the understanding of the elevated smoking rates of people with SMI by comparing smokers with and without SMI on validated biopsychosocial measures. There is a need for interventions that reduce craving, reduce smoking motives, and increase risk awareness among smokers with SMI.

A qualitative study of the views about smoking, licensed cessation aids and e-cigarettes in people with schizophrenia spectrum disorders

Smoking prevalence remains high among people with a mental health condition compared to those without. Understanding people's motivation to quit and their views of smoking cessation support may help to develop future interventions. We conducted a qualitative study to explore the perceptions of 30 people with schizophrenia spectrum disorders who were current smokers, about smoking traditional cigarettes, the appeal of licensed medicines and e-cigarettes for smoking cessation or smoking reduction. The experiences of participants who were motivated to quit were compared with those who were not motivated to quit. Findings suggest traditional cigarettes were pleasurable and licensed cessation aids and e-cigarettes unappealing to participants who were unmotivated to quit. Whereas nicotine replacement products and e-cigarettes may be an appealing smoking cessation or reduction strategy for those motivated to quit. There is a need to find ways of making traditional cigarettes less appealing and alternative less harmful nicotine products (licensed and unlicensed) more appealing and accessible to this group of high risk smokers.

A meta-analysis of craving studies in schizophrenia spectrum disorders

OBJECTIVE

DSM-5 Substance Use Disorders (SUD) are frequent and debilitating comorbidities displayed by patients with schizophrenia spectrum disorders (SZ). One crucial feature of SUD is drug craving, an intense desire to consume a substance, commonly divided into reward and relief dimensions. Here, we conducted a meta-analysis of studies investigating craving in individuals with both SUD and SZ in order to examine whether these patients exhibit a distinct pattern of craving as compared to patients with SUD without SZ.

METHOD

Meta-analysis based on the PRISMA guidelines.

RESULTS

Sixteen relevant publications were identified by a systematic search of databases, which included 1219 individuals (589 SUD-SZ and 630 SUD-without-SZ). Of the 16 studies, 11 focused on tobacco, 3 on cannabis and 2 on cocaine. When considered across all studies, SUD-SZ had significantly higher scores than SUD-without-SZ for global craving with medium effect size (k_{number of studies} = 16, Zr = 0.20 [0.15, 0.26], equivalent d = 0.41, P < 0.001). Discrete patterns emerged for reward (k = 7, Zr = 0.10 [0.02, 0.17], equivalent d = 0.20, P < 0.05) and relief (k = 7, Zr = 0.25 [0.17, 0.33], d = 0.52, P < 0.001) craving, and the direct comparison revealed a significantly greater effect for relief than reward (χ²(1) = 7.40 P = 0.007).

CONCLUSION

These results suggest that SUD-SZ cases experience higher craving, more specifically for relief, in comparison to patients with SUD-without-SZ. These clinical findings can foster the development of tailored addiction therapies for this specific comorbid population.

Smoking Topography Characteristics During a 6-Week Trial of Very Low Nicotine Content Cigarettes in Smokers With Serious Mental Illness

INTRODUCTION

A nicotine-reduction policy could have major benefits for smokers with serious mental illness (SMI). However, potential unintended consequences, such as compensatory smoking, should be considered to ensure that such a policy does not negatively affect this population. The purpose of this secondary analysis was to examine the impact of smoking very low nicotine content (VLNC) cigarettes for 6 weeks on smoking topography characteristics, indicators of compensatory smoking, among smokers with SMI.

AIMS AND METHODS

After a baseline usual brand smoking phase, smokers with SMI (N = 58) were randomly assigned under double-blind conditions to receive either VLNC (0.4 mg nicotine per g tobacco) or normal nicotine content (NNC; 15.8 mg nicotine per g tobacco) research cigarettes for 6 weeks. During two study visits scheduled 6 weeks apart, participants smoked either their usual brand (baseline) or assigned study cigarettes (postrandomization) through a handheld smoking topography device. Univariate analysis of variance compared smoking topography indices with cigarette condition (VLNC vs. NNC) as the between-subjects factor with corresponding baseline topography results included as covariates.

RESULTS

At week 6, participants in the VLNC condition smoked fewer puffs per cigarette and had shorter interpuff intervals compared to participants in the NNC condition (ps < .05). There were no differences between research cigarette conditions at week 6 for cigarette volume, puff volume, puff duration, peak flow rate, or carbon monoxide boost.

CONCLUSIONS

Findings are consistent with acute VLNC cigarette topography studies and indicate that a nicotine-reduction policy is unlikely to lead to compensation among smokers with SMI.

IMPLICATIONS

Given the high smoking rates among people with SMI, understanding how a nicotine-reduction policy may affect this population is critically important. When considering the smoking topography results as a whole, smokers with SMI did not engage in compensatory smoking behavior when using VLNC cigarettes during a 6-week trial. Study findings suggest that compensatory smoking is not likely to occur among smokers with SMI if nicotine content is lowered to minimally addictive levels.

Tobacco smoking, related harm and motivation to quit smoking in people with schizophrenia spectrum disorders

This narrative review focuses on the topic of tobacco smoking amongst people with schizophrenia spectrum disorders. We searched PubMed, PsycInfo and Scopus databases for schizophrenia spectrum disorders and smoking and included articles about the epidemiology of tobacco smoking in people with schizophrenia spectrum disorders, examining the relationship between smoking and mental health. This narrative review describes that a higher prevalence, frequency and impact of both high nicotine dependence and its harmful effects in patients with schizophrenia spectrum disorders compared with those in the general population. Despite several existent theories, the reasons for high smoking rates, the high dependence on nicotine and severity of nicotine withdrawal symptoms are not fully understood. The main aim of this paper is to inform mental health personnel and particularly clinical and health psychologists about the impact and role of tobacco smoking for smokers with schizophrenia spectrum disorders.

Increased Connectivity Between the Nucleus Accumbens and the Default Mode Network in Patients With Schizophrenia During Cigarette Cravings

Objective: Compared to the general population, tobacco smoking cessation rates are lower in populations with schizophrenia. Unfortunately, the potential neurophysiologic mechanisms underlying these low cessation rates in schizophrenia have been seldom studied using functional neuroimaging. Recently, it has been shown that tobacco cravings are increased in smokers with schizophrenia compared to smokers with no comorbid psychiatric disorder. Given the critical role of the brain reward system in the neurobiology of addiction, we sought to examine the functional connectivity of core regions of this system in smokers with schizophrenia during the viewing of appetitive smoking cues. Methods: Smokers with (n = 18) and without (n = 24) schizophrenia were scanned using functional magnetic resonance imaging while viewing appetitive cigarette images. Functional connectivity analyses were performed using the bilateral nucleus accumbens as the seed regions. Results: Smokers with schizophrenia and smokers with no psychiatric comorbidity did not differ in subjective cravings in response to appetitive smoking cues. However, in smokers with schizophrenia relative to control smokers, we found an increased connectivity between the nucleus accumbens and regions involved in the default mode network (e.g., middle temporal gyrus and precuneus), which are involved in self-referential processes. Moreover, a positive correlation was observed between the left nucleus accumbens and left middle temporal gyrus connectivity and cigarette cravings across both groups of smokers. Conclusions: These results highlight a key role of the nucleus accumbens in cigarette craving in schizophrenia and suggest that the subjective valuation of cigarette cues is increased in this population. Similar neurofunctional studies on cravings for other psychoactive substances in schizophrenia are warranted.

Modeling nicotine regulation: A review of studies in smokers with mental health conditions

Smokers with mental health conditions (MHCs) lose approximately 15 years of life relative to non-smokers without MHCs, of which two-thirds are attributable to smoking. The Food and Drug Administration (FDA) recently announced a new regulatory strategy for tobacco that includes a reduction in the nicotine content of cigarettes sold in the US to a minimally-addictive level. This action could improve cessation rates in smokers with MHCs by reducing their dependence on nicotine. However, nicotine reduction also could have unintended negative consequences in smokers with MHCs. Thus, it is important to conduct randomized controlled trials to investigate the potential effects of nicotine reduction in smokers with MHCs. Several studies of the acute or extended effects of nicotine reduction in smokers with emotional disorders or serious mental illness have been recently completed or are underway. Studies to date indicate that when smokers with MHCs are switched, under randomized, double-blind conditions, to cigarettes with very low nicotine content, they reduce their cigarette intake, with minimal or no effects on withdrawal, psychiatric symptoms, or compensatory smoking. However, some deleterious effects of nicotine reduction on cognitive performance measures in smokers with schizophrenia have been observed, which are offset by providing concurrent nicotine replacement. We review these studies and provide suggestions for potentially increasing the effectiveness of a nicotine reduction strategy for reducing smoking in people with MHCs. The research described was conducted in the United States in 2010-2018.

iQOS: evidence of pyrolysis and release of a toxicant from plastic

OBJECTIVE

To evaluate performance of the I quit original smoking (iQOS) heat-not-burn system as a function of cleaning and puffing topography, investigate the validity of manufacturer's claims that this device does not burn tobacco and determine if the polymer-film filter is potentially harmful.

METHODS

iQOS performance was evaluated using five running conditions incorporating two different cleaning protocols. Heatsticks were visually and stereomicroscopically inspected preuse and postuse to determine the extent of tobacco plug charring (from pyrolysis) and polymer-film filter melting, and to elucidate the effects of cleaning on charring. Gas chromatography-mass spectrometry headspace analysis was conducted on unused polymer-film filters to determine if potentially toxic chemicals are emitted from the filter during heating.

RESULTS

For all testing protocols, pressure drop decreased as puff number increased. Changes in testing protocols did not affect aerosol density. Charring due to pyrolysis (a form of organic matter thermochemical decomposition) was observed in the tobacco plug after use. When the manufacturer's cleaning instructions were followed, both charring of the tobacco plug and melting of the polymer-film filter increased. Headspace analysis of the polymer-film filter revealed the release of formaldehyde cyanohydrin at 90°C, which is well below the maximum temperature reached during normal usage.

DISCUSSION

Device usage limitations may contribute to decreases in interpuff intervals, potentially increasing user's intake of nicotine and other harmful chemicals. This study found that the tobacco plug does char and that charring increases when the device is not cleaned between heatsticks. Release of formaldehyde cyanohydrin is a concern as it is highly toxic at very low concentrations.

The effects of nicotine in the neonatal quinpirole rodent model of psychosis: Neural plasticity mechanisms and nicotinic receptor changes

Neonatal quinpirole (NQ) treatment to rats increases dopamine D2 receptor sensitivity persistent throughout the animal's lifetime. In Experiment 1, we analyzed the role of α7 and α4β2 nicotinic receptors (nAChRs) in nicotine behavioral sensitization and on the brain-derived neurotrophic factor (BDNF) response to nicotine in NQ- and neonatally saline (NS)-treated rats. In Experiment 2, we analyzed changes in α7 and α4β2 nAChR density in the nucleus accumbens (NAcc) and dorsal striatum in NQ and NS animals sensitized to nicotine. Male and female Sprague-Dawley rats were neonatally treated with quinpirole (1mg/kg) or saline from postnatal days (P)1-21. Animals were given ip injections of either saline or nicotine (0.5mg/kg free base) every second day from P33 to P49 and tested on behavioral sensitization. Before each injection, animals were ip administered the α7 nAChR antagonist methyllycaconitine (MLA; 2 or 4mg/kg) or the α4β2 nAChR antagonist dihydro beta erythroidine (DhβE; 1 or 3mg/kg). Results revealed NQ enhanced nicotine sensitization that was blocked by DhβE. MLA blocked the enhanced nicotine sensitization in NQ animals, but did not block nicotine sensitization. NQ enhanced the NAcc BDNF response to nicotine which was blocked by both antagonists. In Experiment 2, NQ enhanced nicotine sensitization and enhanced α4β2, but not α7, nAChR upregulation in the NAcc. These results suggest a relationship between accumbal BDNF and α4β2 nAChRs and their role in the behavioral response to nicotine in the NQ model which has relevance to schizophrenia, a behavioral disorder with high rates of tobacco smoking.

A behavioral economic perspective on smoking persistence in serious mental illness

Serious mental illness (SMI) is associated with disproportionately high rates of cigarette smoking. The identification of factors that contribute to persistent smoking in people with SMI may lead to the development and adoption of tobacco control policies and treatment approaches that help these smokers quit. This commentary examines factors underlying smoking persistence in people with SMI from the perspective of behavioral economics, a discipline that applies economic principles to understanding drug abuse and dependence. Studies, conducted in the Northeastern US within the past 30years, that compare the reinforcing effects of nicotine and the costs of smoking in smokers with and without schizophrenia and depression are discussed, and interventions that may reduce the reinforcing efficacy of nicotine and increase the costs of smoking in people with SMI are described.

Smoking Topography Characteristics of Very Low Nicotine Content Cigarettes, With and Without Nicotine Replacement, in Smokers With Schizophrenia and Controls

INTRODUCTION

Reducing the nicotine content of cigarettes to a minimally addictive level has been proposed as a regulatory strategy for reducing tobacco dependence. However, smokers with schizophrenia (SS) may be prone to changing their smoking topography in efforts to compensate for the reduction in nicotine content. The aims of this study were to compare smoking topography characteristics of usual-brand and very low nicotine content (VLNC) cigarettes in SS and control smokers without psychiatric illness (CS), and to determine whether nicotine replacement reversed any changes in topography produced by VLNC cigarettes.

METHODS

Using a within-subjects, counter-balanced design, SS (n = 27) and CS (n = 23) smoked usual brand cigarettes, VLNC cigarettes while wearing placebo patches (VLNC + PLA), or VLNC cigarettes while wearing transdermal nicotine patches totaling 42mg (VLNC + NIC) during 5-hour ad libitum smoking sessions. Cigarettes were smoked through topography measurement devices.

RESULTS

Across conditions, SS smoked more puffs per session and per cigarette, had higher cigarette volumes, and had shorter inter-puff intervals than CS (Ps < .01). During VLNC cigarette sessions, puff duration increased and time between puffs decreased, but participants smoked fewer puffs, resulting in a net decrease in cigarette and total session volume (Ps < .001). There were no significant interactions between group and condition.

CONCLUSIONS

These findings indicate that acute use of VLNC cigarettes does not increase intensity of smoking in SS, and support the feasibility of a nicotine reduction policy.

IMPLICATIONS

Reducing the nicotine in cigarettes to a minimally addictive level has been proposed as a means of reducing tobacco dependence. However, smokers, particularly those with schizophrenia (SS) may alter their puffing in an attempt to extract more nicotine from VLNC cigarettes. This study compared smoking topography of usual brand versus VLNC cigarettes, combined with placebo or transdermal nicotine patches, in SS and controls. Although some changes in topography were indicative of compensatory smoking, total puffs and total cigarette volume were reduced with VLNC cigarettes, indicating that acute VLNC cigarette use does not increase smoking in SS.

Smoking cessation and reduction in people with chronic mental illness

The high prevalence of cigarette smoking and tobacco related morbidity and mortality in people with chronic mental illness is well documented. This review summarizes results from studies of smoking cessation treatments in people with schizophrenia, depression, anxiety disorders, and post-traumatic stress disorder. It also summarizes experimental studies aimed at identifying biopsychosocial mechanisms that underlie the high smoking rates seen in people with these disorders. Research indicates that smokers with chronic mental illness can quit with standard cessation approaches with minimal effects on psychiatric symptoms. Although some studies have noted high relapse rates, longer maintenance on pharmacotherapy reduces rates of relapse without untoward effects on psychiatric symptoms. Similar biopsychosocial mechanisms are thought to be involved in the initiation and persistence of smoking in patients with different disorders. An appreciation of these common factors may aid the development of novel tobacco treatments for people with chronic mental illness. Novel nicotine and tobacco products such as electronic cigarettes and very low nicotine content cigarettes may also be used to improve smoking cessation rates in people with chronic mental illness.

Smoking topography in Korean American and white men: preliminary findings

This is the first study of Korean Americans' smoking behavior using a topography device. Korean American men smoke at higher rates than the general U.S.

POPULATION

Korean American and White men were compared based on standard tobacco assessment and smoking topography measures. They smoked their preferred brand of cigarettes ad libitum with a portable smoking topography device for 24 h. Compared to White men (N = 26), Korean American men (N = 27) were more likely to smoke low nicotine-yield cigarettes (p < 0.001) and have lower Fagerstrom nicotine dependence scores (p = 0.04). Koreans smoked fewer cigarettes with the device (p = 0.01) than Whites. Controlling for the number of cigarettes smoked, Koreans smoked with higher average puff flows (p = 0.05), greater peak puff flows (p = 0.02), and shorter interpuff intervals (p < 0.001) than Whites. Puff counts, puff volumes, and puff durations did not differ between the two groups. This study offers preliminary insight into unique smoking patterns among Korean American men who are likely to smoke low nicotine-yield cigarettes. We found that Korean American men compensated their lower number and low nicotine-yield cigarettes by smoking with greater puff flows and shorter interpuff intervals than White men, which may suggest exposures to similar amounts of nicotine and harmful tobacco toxins by both groups. Clinicians will need to consider in identifying and treating smokers in a mutually aggressive manner, irrespective of cigarette type and number of cigarette smoked per day.

Dementia praecox redux: a systematic review of the nicotinic receptor as a target for cognitive symptoms of schizophrenia

Most individuals with schizophrenia suffer some cognitive dysfunction: such deficits are predictive of longer-term functioning; and current dopamine-blocking antipsychotics have made little impact on this domain. There is a pressing need to develop novel pharmacological agents to tackle this insidious but most disabling of problems. The acetylcholinergic system is involved in cognitive and attentional processing, and its metabotropic and nicotinic receptors are widespread throughout the brain. Deficits in acetylcholinergic functioning occur in schizophrenia, and high rates of tobacco smoking have been posited to represent a form of self-medication. The nicotinic acetylcholine receptor (nAChR) has emerged as a putative target to improve cognitive deficits in schizophrenia, and this study systematically reviewed the emerging data. Nineteen studies were identified, covering three compound classes: agonists at the α7 and α 4β2 nAChRs, and positive allosteric modulators. Overall data are underwhelming: some studies showed significant improvements in cognition but as many studies had negative findings. It remains unclear if this represents drug limitations or nascent study methodology problems. The literature is particularly hindered by variability in inclusion of smokers, generally small sample sizes, and a lack of consensus on cognitive test batteries. Future work should evaluate longer-term outcomes, and, particularly, the effects of concomitant cognitive training.

Nicotine usage is associated with elevated processing speed, spatial working memory, and visual learning performance in youth at ultrahigh-risk for psychosis

Research has stressed a link between nicotine and cognition in schizophrenia but this has not been examined in youth at ultrahigh-risk (UHR) for psychosis. A total of 35 UHR and 32 control participants were assessed for naturalistic nicotine-use and administered a cognitive battery. Smoking was reported more frequently in the UHR group (46%) than controls (22%). Frequent smoking was associated with elevated cognitive performance in the UHR group, highlighting a need for experimental investigations.

Gender differences in characteristics and outcomes of smokers diagnosed with psychosis participating in a smoking cessation intervention

While research has identified gender differences in characteristics and outcomes of smokers in the general population, no studies have examined this among smokers with psychosis. This study aimed to explore gender differences among 298 smokers with psychosis (schizophrenia, schizoaffective and bipolar affective disorder) participating in a smoking intervention study. Results revealed a general lack of gender differences on a range of variables for smokers with psychosis including reasons for smoking/quitting, readiness and motivation to quit, use of nicotine replacement therapy, and smoking outcomes including point prevalence or continuous abstinence, and there were no significant predictors of smoking reduction status according to gender at any of the follow-up time-points. The current study did find that female smokers with psychosis were significantly more likely than males to report that they smoked to prevent weight gain. Furthermore, the females reported significantly more reasons for quitting smoking and were more likely to be driven by extrinsic motivators to quit such as immediate reinforcement and social influence, compared to the male smokers with psychosis. Clinical implications include specifically focussing on weight issues and enhancing intrinsic motivation to quit smoking for female smokers with psychosis; and strengthening reasons for quitting among males with psychosis.

Elevation of dopamine induced by cigarette smoking: novel insights from a [11C]-+-PHNO PET study in humans

Positron emission tomography (PET) has convincingly provided in vivo evidence that psychoactive drugs increase dopamine (DA) levels in human brain, a feature thought critical to their reinforcing properties. Some controversy still exists concerning the role of DA in reinforcing smoking behavior and no study has explored whether smoking increases DA concentrations at the D3 receptor, speculated to have a role in nicotine's addictive potential. Here, we used PET and [(11)C]-(+)-PHNO ([(11)C]-(+)-4-propyl-3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4]oxazin-9-ol) to test the hypothesis that smoking increases DA release (decreases [(11)C]-(+)-PHNO binding) in D2-rich striatum and D3-rich extra-striatal regions and is related to craving, withdrawal and smoking behavior. Ten participants underwent [(11)C]-(+)-PHNO scans after overnight abstinence and after smoking a cigarette. Motivation to smoke (smoking topography), mood, and craving were recorded. Smoking significantly decreased self-reported craving, withdrawal, and [(11)C]-(+)-PHNO binding in D2 and D3-rich areas (-12.0 and -15.3%, respectively). We found that motivation to smoke (puff rate) predicted magnitude of DA release in limbic striatum, and the latter was correlated with decreased craving and withdrawal symptoms. This is the first report suggesting that, in humans, DA release is increased in D3-rich areas in response to smoking. Results also support the preferential involvement of the limbic striatum in motivation to smoke, anticipation of pleasure from cigarettes and relief of withdrawal symptoms. We propose that due to the robust effect of smoking on [(11)C]-(+)-PHNO binding, this radiotracer represents an ideal translational tool to investigate novel therapeutic strategies targeting DA transmission.

A systematic review and analysis of data reduction techniques for the CReSS smoking topography device

Introduction: Characterising smoking behaviour in an objective and ecologically valid manner is integral to understanding health complications associated with tobacco use. Smoking topography (ST) provides a representation of the physical attributes of smoking. However, there is no clear guidance on ST data exclusion and reduction techniques and the impact of different techniques.

Methods: A search was conducted using MEDLINE, PubMed, and Scopus and limited to studies published between 2001‒2012. The search identified 23 studies using the CReSS device.

Results: Few studies reported data reduction (n = 9) and exclusion (n = 4) criteria. Four data reduction techniques emerged and were applied to an existing dataset (n = 193, Mage = 38.98, FTND = 5.19, mean 17.23 cigarettes/day). Using repeated measures ANOVA, there were significant (p < 0.05) differences among all techniques for puff volume, peak flow, puff duration and interpuff interval, which were attenuated upon controlling for puff count.

Conclusions: This review highlights the inconsistency in the literature regarding the disclosure of smoking topography data treatment and provides clear evidence that outcomes vary depending on the technique used. Greater transparency is needed and consideration should be given by researchers to the potential impact of methodological decisions on study findings.

Chronic nicotine attenuates phencyclidine-induced impulsivity in a mouse serial reaction time task

Schizophrenia is a disorder characterized by positive, negative, and cognitive symptoms. While positive symptoms can be effectively treated with typical antipsychotic medication, which generally affects the dopaminergic system, negative and cognitive symptoms, including attentional deficits and impulsive behavior, are less sensitive to standard treatments. It has further been well documented that schizophrenic patients use tobacco products at a rate much higher than the general population, and this persists despite treatment. It has been argued this behavior may be a form of self-medication, to alleviate some symptoms of schizophrenia. It has further been posited that prefrontal glutamatergic hypofunction may underlie some aspects of schizophrenia, and in accordance with this model, systemic phencyclidine has been used to model the disease. We employed a modified 5-choice serial reaction time test, a paradigm that is often used to investigate many of the treatment-resistant symptoms of schizophrenia including impulsivity, selective attention, and sustained attention/cognitive vigilance, to determine the medicinal effects of nicotine. We demonstrate that chronic oral, but not acute injections of nicotine can selectively attenuate phencyclidine-induced increases in impulsivity without affecting other measures of attention. This suggests that nicotine use by schizophrenics may provide some relief of distinct symptoms that involve impulsive behaviors.

Effects of smoking abstinence on cigarette craving, nicotine withdrawal, and nicotine reinforcement in smokers with and without schizophrenia

INTRODUCTION

Schizophrenia is associated with a high prevalence of cigarette smoking. The aims of this study were to compare smokers with schizophrenia (SS) and control smokers without psychiatric illness (CS) on (a) cigarette craving and nicotine withdrawal symptom severity during a 72-hr smoking abstinence period; (b) nicotine reinforcement, before and after abstinence; and (c) latency to smoking lapse following abstinence. We also explored mediators of smoking lapse in SS and CS.

METHODS

SS (n = 28) and CS (n = 27) underwent a nicotine versus denicotinized cigarette puff choice task before and after a 72-hr period of smoking abstinence that was experimentally controlled by providing cash reinforcement contingent on biochemical verification of abstinence. Twenty-four hours after the second choice task, participants could receive a low-value reinforcer if they had continued to abstain since the previous day. Those who remained abstinent were recontacted a week later to determine time of their smoking lapse.

RESULTS

SS reported more severe cigarette craving and nicotine withdrawal symptoms throughout the 72-hr abstinence period, had greater nicotine preference after abstinence, and lapsed back to smoking significantly sooner than CS. The relationship between group and smoking lapse latency was mediated by baseline depression and nicotine withdrawal symptom severity but not by effects of abstinence on craving or nicotine reinforcement.

CONCLUSIONS

Overall, these results indicate that negative affect is a key contributor to poor smoking cessation outcomes among those with schizophrenia.

Cigarette rod length and its impact on serum cotinine and urinary total NNAL levels, NHANES 2007-2010

INTRODUCTION

Research suggests that smokers of slim, long, or ultralong cigarettes may have a perception of reduced harm from their own brand. This study compared serum cotinine and urinary total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanonol (NNAL) levels among smokers of regular-sized (68-72mm), king-sized (79-88mm), and long (94-101mm) or ultralong (110-121mm) cigarettes.

METHODS

Nationally representative data from the 2007-2008 and 2009-2010 National Health and Nutrition Examination Survey were analyzed for 3,699 current smokers aged ≥20 years. Biomarker levels were summarized using geometric means (GMs). Multivariate linear regression analyses were performed to assess the effect of cigarette rod length on log-transformed serum cotinine and creatinine-adjusted urinary total NNAL levels.

RESULTS

The GM of serum cotinine level was higher among smokers of long/ultralong cigarettes (263.15ng/ml) compared with smokers of regular-sized (173.13ng/ml) or king-sized (213.79ng/ml) cigarettes. Similarly, the GM of creatinine-adjusted NNAL levels was higher among smokers of long/ultralong cigarettes (0.48ng NNAL/mg of creatinine) compared with smokers of regular-sized (0.34ng NNAL/mg of creatinine) or king-sized (0.33ng NNAL/mg of creatinine) cigarettes. After adjusting for potential confounders, mean cotinine and NNAL levels were both significantly higher among smokers of long/ultralong cigarettes compared with levels observed in smokers of either regular-sized or king-sized cigarettes. However, no significant differences were observed between smokers of regular-sized and king-sized cigarettes in mean levels of cotinine or NNAL.

CONCLUSIONS

Significantly elevated tobacco biomarker levels were observed among smokers of long/ultralong cigarettes compared with smokers of regular-sized or king-sized cigarettes. This underscores the need to educate the public about the dangers of all tobacco products.

A test of the cognitive self-medication hypothesis of tobacco smoking in schizophrenia

BACKGROUND

Heavier tobacco smoking among people with schizophrenia (SCZ) has been suggested to reflect self-medication of cognitive deficits. The idea that cognitive-enhancing effects of nicotine are a primary motivator of tobacco consumption in SCZ and that abstinence would deprive SCZ of such beneficial effects might explain hesitation among providers to pursue smoking cessation in SCZ. This study tested predictions of the cognitive self-medication hypothesis.

METHODS

In three counterbalanced sessions, 17 SCZ and 17 healthy control subjects (HCS), all smokers, were tested under ad libitum smoking or 3.5 hours after abstaining and receiving a nicotine (14 mg/24 hours) or placebo patch.

RESULTS

Attention task performance was improved by transdermal nicotine relative to placebo, with intermediate performance by ad libitum smoking. These effects were of similar size in SCZ and HCS and did not reflect remediation of functions disproportionately impaired in SCZ. Although more SCZ reported that the need to concentrate influenced their smoking, this was not reflected by the actual behavior of these patients. Self-reported ability to concentrate changed with nicotine status in HCS but not SCZ, suggesting insensitivity of SCZ to nicotine-derived performance benefits. Nicotine plasma concentrations after ad libitum smoking were not associated with performance benefits but instead with the propensity to experience nicotine withdrawal upon abstinence. This association was seen selectively in SCZ, suggesting a possible reason for heavier smoking.

CONCLUSIONS

These findings suggest that subjective or objective attentional benefits are unlikely the primary driving force of tobacco consumption in SCZ and should not discourage providers from supporting quit attempts.

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.

Task persistence predicts smoking cessation in smokers with and without schizophrenia

Smokers attempting to quit should benefit from persisting in cognitive and behavioral coping in order to achieve and maintain abstinence. Task persistence, which describes the act of persisting in a difficult or effortful task, is likely to be required in the face of distressing smoking cues, urges to smoke, or other nicotine withdrawal symptoms. This study examined whether task persistence (also called distress tolerance) could prospectively predict smoking cessation in a mixed sample of smokers with and without schizophrenia. Smokers with schizophrenia or schizoaffective disorder (n = 71) and nonpsychiatric smokers (n = 78) seeking treatment at state-funded tobacco dependence treatment clinics completed tests of task persistence before their target quit date, and then provided tobacco use data over the 6 months after their quit date. Findings from generalized estimating equations support the hypothesis that task persistence as measured by a mirror-tracing task predicts smoking cessation while controlling for important covariates such as psychiatric diagnosis, nicotine dependence, and confidence in ability to quit. These findings add to the literature by corroborating reports suggesting that task persistence may make important contributions to smoking cessation success, and by indicating that the contribution of task persistence to smoking cessation is similar for smokers with schizophrenia and nonpsychiatric smokers. These results suggest that efforts to target task persistence in smoking cessation counseling protocols may be warranted.

Nicotine intake and smoking topography in smokers with bipolar disorder

OBJECTIVES

Cigarette smoking behavior in bipolar disorder (BPD), including the effects of mood-stabilizing medications, has not been well characterized.

METHODS

We compared serum nicotine, nicotine metabolite levels, and smoking topography in 75 smokers with BPD to 86 control smokers (CON). For some comparisons, an additional control group of 75 smokers with schizophrenia (SCZ) were included.

RESULTS

There were no differences between the BPD and CON groups in baseline smoking characteristics or serum nicotine or cotinine levels. Fifty-one smokers with BPD (68.9%) were taking one of the following mood stabilizers: valproic acid, lamotrigine, carbamazepine, oxcarbazepine, lithium, or topiramate. The 3-hydroxycotinine-to-cotinine ratio, a marker of cytochrome P450 2A6 (CYP2A6) metabolic activity, was significantly higher in BPD versus CON and versus SCZ (0.68 versus 0.49 versus 0.54; p =0.002). The difference between groups, however, was no longer significant when the analysis was repeated with those taking hepatic enzyme-inducing drugs (carbamazepine, oxcarbazepine, and topiramate) included as a covariate. The time between puffs, or interpuff interval (IPI), was shorter in BPD versus CON by an average of 3.0sec (p<0.05), although this was no longer significant when we removed smokers from the analysis of those taking hepatic enzyme inducers.

CONCLUSIONS

Smokers with BPD are not different from CON on most measures of nicotine intake and smoking topography. We found an increased rate of nicotine metabolism in smokers taking mood stabilizers that are hepatic enzyme inducers, including carbamazepine, oxcarbazepine, and topiramate. Smokers with rapid nicotine metabolism might be expected to smoke more intensely to compensate for the more rapid disappearance of nicotine from the blood and brain, and may have more difficulty in quitting smoking, although this requires further study.

Separate and combined effects of very low nicotine cigarettes and nicotine replacement in smokers with schizophrenia and controls

INTRODUCTION

The prevalence of smoking among people with schizophrenia in the United States is about 3 times that of the general population. Novel approaches are needed to reduce rates of smoking-related morbidity and mortality among these smokers.

METHODS

This study used a within-subjects design to investigate the separate and combined effects of sensorimotor replacement for smoking (very low nicotine content [VLNC] cigarettes vs. no cigarettes) and transdermal nicotine replacement (42 mg nicotine [NIC] vs. placebo [PLA] patches) in smokers with schizophrenia (SS; n = 30) and control smokers without psychiatric illness (CS; n = 26). Each session contained a 5-hr controlled administration period in which participants underwent the following conditions, in counterbalanced order: VLNC + NIC, VLNC + PLA, no cigarettes + NIC, no cigarettes + PLA, usual-brand cigarettes + no patches. Next, participants completed measures of cigarette craving, nicotine withdrawal, smoking habit withdrawal, and cigarette subjective effects, followed by a 90-min period of ad libitum usual-brand smoking.

RESULTS

Smoking VLNC cigarettes during the controlled administration periods reduced cigarette craving, nicotine withdrawal symptoms, habit withdrawal symptoms, and usual-brand smoking in SS and CS relative to the no cigarette conditions. VLNC cigarettes were well accepted by both groups and did not affect psychiatric symptom levels in SS. Transdermal nicotine significantly reduced cigarette craving but did not affect usual-brand smoking.

CONCLUSIONS

These findings suggest that reducing the nicotine content of cigarettes to nonaddictive levels may be a promising approach for reducing nicotine dependence among people with schizophrenia.

Rapid smoking may not be aversive in schizophrenia

INTRODUCTION

Aversive smoking has been investigated as a smoking cessation technique that involves rapid smoking in a clinic or laboratory and typically involves (a) puffing every 6-10 s or (b) smoking 3 or more cigarettes sequentially in 8-20 min. Rapid smoking usually results in dizziness, sore throat, nausea, and other unpleasant feelings.

METHODS

To explore rapid smoking, 161 smokers (75 with schizophrenia [SS]; 86 controls [CON]) were assessed in a single day (24 ± 2 hr), ad libitum smoking topography session using the Clinical Research Support System micro portable topography device.

RESULTS

SS smoked significantly more cigarettes in the 24-hr period versus CON and the time between puffs, or interpuff interval (IPI) was shorter in SS versus CON by an average of 6.5 s (p < .001). The median IPI was also significantly shorter in SS versus CON (9.3 vs.15.7 s; p < .001). SS were twice as likely to have IPIs ≤ 6 s than CON (OR = 2.32, 95% CI = 1.68, 3.20; p < .001). SS were also more likely to smoke 3 or more cigarettes in any 20 min during a 24-hr topography session (OR = 2.32, 95% CI = 1.03, 2.44; p < .001). Rapid smoking was associated with baseline characteristics of smoking more cigarettes per day, higher Fagerström score, and higher carbon monoxide level but not with serum cotinine values or trans-3'-hydroxycotinine/cotinine ratios.

CONCLUSIONS

Using either definition, SS exhibit patterns of rapid smoking that they seemingly do not experience as aversive, since it reflects their naturalistic pattern of smoking, outside of the laboratory.

Genetics of schizophrenia and smoking: an approach to studying their comorbidity based on epidemiological findings

The association between schizophrenia and tobacco smoking has been described in more than 1,000 articles, many with inadequate methodology. The studies on this association can focus on: (1) current smoking, ever smoking or smoking cessation; (2) non-psychiatric controls or controls with severe mental illness (e.g., bipolar disorder); and (3) higher smoking frequency or greater usage in smokers. The association with the most potential for genetic studies is that between ever daily smoking and schizophrenia; it may reflect a shared genetic vulnerability. To reduce the number of false-positive genes, we propose a three-stage approach derived from epidemiological knowledge. In the first stage, only genetic variations associated with ever daily smoking that are simultaneously significant within the non-psychiatric controls, the bipolar disorder controls and the schizophrenia cases will be selected. Only those genetic variations that are simultaneously significant in the three hypothesis tests will be tested in the second stage, where the prevalence of the genes must be significantly higher in schizophrenia than in bipolar disorder, and significantly higher in bipolar disorder than in controls. The genes simultaneously significant in the second stage will be included in a third stage where the gene variations must be significantly more frequent in schizophrenia patients who did not start smoking daily until their 20s (late start) versus those who had an early start. Any genetic approach to psychiatric disorders may fail if attention is not given to comorbidity and epidemiological studies that suggest which comorbidities are likely to be explained by genetics and which are not. Our approach, which examines the results of epidemiological studies on comorbidities and then looks for genes that simultaneously satisfy epidemiologically suggested sets of hypotheses, may also apply to the study of other major illnesses.