Non-treatment-seeking heavy drinkers: effects of chronic cigarette smoking on brain structure

Associations Between the Wisconsin Inventory of Smoking Dependence Motives and Regional Brain Volumes in Adult Smokers

INTRODUCTION

The Wisconsin Inventory of Smoking Dependence Motives (WISDM-68) is a 68-item questionnaire to assess nicotine dependence as a multifactorial construct based on 13 theoretically derived smoking motives. Chronic smoking is associated with structural changes in brain regions implicated in the maintenance of smoking behavior; however, associations between brain morphometry and the various reinforcing components of smoking behavior remain unexamined. The present study investigated the potential association between smoking dependence motives and regional brain volumes in a cohort of 254 adult smokers.

AIMS AND METHODS

The WISDM-68 was administered to participants at the baseline session. Structural magnetic resonance brain imaging (MRI) data from 254 adult smokers (Mage = 42.7 ± 11.4) with moderate to severe nicotine dependence (MFTND = 5.4 ± 2.0) smoking for at least 2 years (Myears = 24.3 ± 11.8) were collected and analyzed with Freesurfer.

RESULTS

Vertex-wise cluster analysis revealed that high scores on the WISDM-68 composite, secondary dependence motives (SDM) composite, and multiple SDM subscales were associated with lower cortical volume in the right lateral prefrontal cortex (cluster-wise p's < .035). Analysis of subcortical volumes (ie, nucleus accumbens, amygdala, caudate, and pallidum) revealed several significant associations with WISDM-68 subscales, dependence severity (Fagerström Test for Nicotine Dependence), and overall exposure (pack-years). No significant associations between cortical volume and other nicotine dependence measures or pack-years were observed.

CONCLUSIONS

Results suggest that smoking motives may play a larger role in cortical abnormalities than addiction severity and smoking exposure per se, whereas subcortical volumes are associated with smoking motives, addiction severity, and smoking exposure.

IMPLICATIONS

The present study reports novel associations between the various reinforcing components of smoking behavior assessed by the WISDM-68 and regional brain volumes. Results suggest that the underlying emotional, cognitive, and sensory processes that drive non-compulsive smoking behaviors may play a larger role in gray matter abnormalities of smokers than smoking exposure or addiction severity.

Alcohol use disorder: Neuroimaging evidence for accelerated aging of brain morphology and hypothesized contribution to age-related dementia

Excessive alcohol use curtails longevity by rendering intoxicated individuals vulnerable to heightened risk from accidents, violence, and alcohol poisoning, and makes chronically heavy drinkers vulnerable to acceleration of age-related medical and psychiatric conditions that can be life threatening (Yoon, Chen, Slater, Jung, & White, 2020). Thus, studies of factors influencing age-alcohol interactions must consider the potential that the alcohol use disorder (AUD) population may not represent the oldest ages of the unaffected population and may well have accrued comorbidities associated with both AUD and aging itself. Herein, we focus on the aging of the brains of men and women with AUD, keeping AUD contextual factors in mind. Knowledge of the potential influence of the AUD-associated co-factors on the condition of brain structure may lead to identifying modifiable risk factors to avert physical declines and may reverse or arrest further AUD-related degradation of the brain. In this narrative review, we 1) describe quantitative, controlled studies of brain macrostructure and microstructure of adults with AUD, 2) consider the possibility of recovery of brain integrity through harm reduction with sustained abstinence or reduced drinking, and 3) speculate on the ramifications of accelerated aging in AUD as contributing to age-related dementia.

Associations between right inferior frontal gyrus morphometry and inhibitory control in individuals with nicotine dependence

BACKGROUND

The hyperdirect pathway - a circuit involved in executing inhibitory control (IC) - is dysregulated among individuals with nicotine dependence. The right inferior frontal gyrus (rIFG), a cortical input to the hyperdirect circuit, has been shown to be functionally and structurally altered among nicotine-dependent people who smoke. The rIFG is composed of 3 cytoarchitecturally distinct subregions: The pars opercularis, pars triangularis, and pars orbitalis. The present study assessed the relationship between rIFG subregion morphometry and inhibitory control among individuals with nicotine dependence.

METHODS

Behavioral and magnetic resonance brain imaging (MRI) data from 127 nicotine-dependent adults who smoke (MFTND = 5.4, ± 1.9; MCPD = 18.3, ± 7.0; Myears = 25.04, ± 11.97) (Mage = 42.9, ± 11.1) were assessed. Brain morphometry was assessed from T1-weighted MRIs using Freesurfer. IC was assessed with a response-inhibition Go/Go/No-Go (GGNG) task and a smoking relapse analog task (SRT).

RESULTS AND CONCLUSIONS

Vertex-wise analyses revealed that GGNG task scores were positively associated with cortical thickness and volume in the right pars triangularis (cluster-wise p = 0.006, 90% CI = 0.003 - 0.009; cluster-wise p = 0.040, 90% CI = 0.032 - 0.048), and the ability to inhibit ad lib smoking during the SRT was positively associated with cortical thickness in the right pars orbitalis (cluster-wise p = 0.011, 90% CI = 0.007 - 0.015). Our results indicate that cortical thickness of distinct rIFG subregions may serve as biomarkers for unique forms of IC deficits.

Effect of alcohol, tobacco, and cannabis co-use on gray matter volume in heavy drinkers

OBJECTIVE

Alcohol, tobacco, and cannabis are the three most frequently used drugs in the United States and co-use is common. Alcohol, tobacco, and cannabis use has been separately associated with altered brain structure, and alcohol and tobacco co-use results in decreases in gray matter volume. Less is known about the effect of alcohol and cannabis co-use, and alcohol, tobacco, and cannabis tri-use. Therefore, this study examined the effect of co- and tri-use on gray matter volume, a measure of brain cell density, in heavy drinkers.

METHOD

Heavy drinkers (n = 237; 152m/85f; age = 32.52; white = 111; black = 28; Latino = 9; American Indian = 2; Pacific Islander = 4; Asian = 59; mixed = 15; other = 9) were classified into four groups based on their alcohol, tobacco, and cannabis use: alcohol only users (n = 70), alcohol and tobacco co-users (n = 90), alcohol and cannabis co-users (n = 35), and alcohol, tobacco, and cannabis tri-users (n = 42). All participants completed a structural MRI scan. Voxel-based morphometry was conducted to evaluate the effect of co-use on gray matter volume, with alcohol only users as the reference group. Age, sex, and scanner were included as covariates.

RESULTS

Alcohol and tobacco co-users had significantly decreased left orbitofrontal gray matter volume relative to alcohol only users (Cohen's d = .79). There were no differences in gray matter volume between the alcohol only and alcohol and cannabis co-users, or between the alcohol only and tri-user groups.

CONCLUSION

The additive effect of tobacco co-use on gray matter volumes in heavy drinkers was limited and localized. The effect of tri-use of alcohol, tobacco, and cannabis may have interacted, such that overlapping cannabis and tobacco use masked volume differences present in separate co-using groups. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Integrating a brief alcohol intervention with tobacco addiction treatment in primary care: qualitative study of health care practitioner perceptions

BACKGROUND

Randomized trials of complex interventions are increasingly including qualitative components to further understand factors that contribute to their success. In this paper, we explore the experiences of health care practitioners in a province wide smoking cessation program (the Smoking Treatment for Ontario Patients program) who participated in the COMBAT trial. This trial examined if the addition of an electronic prompt embedded in a Clinical Decision Support System (CDSS)-designed to prompt practitioners to Screen, provide a Brief intervention and Referral to Treatment (SBIRT) to patients who drank alcohol above the amounts recommended by the Canadian Cancer Society guidelines-influenced the proportion of practitioners delivering a brief intervention to their eligible patients. We wanted to understand the factors influencing implementation and acceptability of delivering a brief alcohol intervention for treatment-seeking smokers for health care providers who had access to the CDSS (intervention arm) and those who did not (control arm).

METHODS

Twenty-three health care practitioners were selected for a qualitative interview using stratified purposeful sampling (12 from the control arm and 11 from the intervention arm). Interviews were 45 to 90 min in length and conducted by phone using an interview guide that was informed by the National Implementation Research Network's Hexagon tool. Interview recordings were transcribed and coded iteratively between three researchers to achieve consensus on emerging themes. The preliminary coding structure was developed using the National Implementation Research Network's Hexagon Tool framework and data was analyzed using the framework analysis approach.

RESULTS

Seventy eight percent (18/23) of the health care practitioners interviewed recognized the need to simultaneously address alcohol and tobacco use. Seventy four percent (17/23), were knowledgeable about the evidence of health risks associated with dual alcohol and tobacco use but 57% (13/23) expressed concerns with using the Canadian Cancer Society guidelines to screen for alcohol use. Practitioners acknowledged the value of adding a validated screening tool to the STOP program's baseline questionnaire (19/23); however, following through with a brief intervention and referral to treatment proved challenging due to lack of training, limited time, and fear of stigmatizing patients. Practitioners in the intervention arm (5/11; 45%) might not follow the recommendations from CDSS if these recommendations are not perceived as beneficial to the patients.

CONCLUSIONS

The results of the study show that practitioners' beliefs were reflective of the current social norms around alcohol use and this influenced their decision to offer a brief alcohol intervention. Future interventions need to emphasize both organizational and sociocultural factors as part of the design. The results of this study point to the need to change social norms regarding alcohol in order to effectively implement interventions that target both alcohol and tobacco use in primary care clinics. Trial registration ClinicalTrials.gov NCT03108144. Retrospectively registered 11 April 2017, https://www.clinicaltrials.gov/ct2/show/NCT03108144.

High-intensity binge drinking is associated with cigarette smoking and e-cigarette use among US adults aged 40-64 years: Findings from the 2017 BRFSS survey

INTRODUCTION

This study aims to assess the association of cigarette smoking, including e-cigarette use, with level of binge drinking, especially high-intensity and extreme high-intensity binge drinking, among a nationally representative sample of middle-aged US adults.

METHODS

Data were derived from the 2017 Behavioral Risk Factor Surveillance System (BRFSS). The final sample consisted of 162748 respondents aged 40–64 years (48.7% male). Weighted distributions of sample characteristics were estimated by intensity of binge drinking. Pearson chi-squared tests were used to compare groups. Bivariate and multivariate logistic regressions were used to estimate crude and adjusted odds ratios to indicate the strength of the association between independent variables and each level of binge drinking.

RESULTS

In all, 2.3% and 0.7% of the sample reported high-intensity and extreme high-intensity binge drinking, respectively. Past-month high-intensity and extreme high-intensity binge drinking were reported in 36.3% and 45.0% of smokers, respectively. Mental distress was positively associated with both levels of high-intensity binge drinking; having multiple chronic health conditions was negatively associated with past-month high-intensity binge drinking. Smokers had 3.27 (95% CI: 2.69–3.98) and 4.14 (95% CI: 3.12–5.49) times greater odds of reporting past-month high-intensity and extreme high-intensity binge drinking, respectively. E-cigarette users had 1.56 (95% CI: 1.01–2.42) times increased odds of reporting past-month high-intensity binge drinking, but not extreme high-intensity binge drinking. The largest odds were seen among dual users reporting extreme high-intensity binge drinking (AOR=6.05; 95% CI: 3.78–9.68) in the past month.

CONCLUSIONS

Cigarette smoking and e-cigarette use were potentially strong risk factors for high-intensity binge drinking, with cigarette smoking associated with extreme high-intensity binge drinking.

Sex/gender differences in brain function and structure in alcohol use: A narrative review of neuroimaging findings over the last 10 years

Over the last 10 years, rates of alcohol use disorder (AUD) have increased in women by 84% relative to a 35% increase in men. Rates of alcohol use and high-risk drinking have also increased in women by 16% and 58% relative to a 7% and 16% increase in men, respectively, over the last decade. This robust increase in drinking among women highlights the critical need to identify the underlying neural mechanisms that may contribute to problematic alcohol consumption across sex/gender (SG), especially given that many neuroimaging studies are underpowered to detect main or interactive effects of SG on imaging outcomes. This narrative review aims to explore the recent neuroimaging literature on SG differences in brain function and structure as it pertains to alcohol across positron emission tomography, magnetic resonance imaging, and functional magnetic resonance imaging modalities in humans. Additional work using magnetic resonance spectroscopy, diffusion tensor imaging, and event-related potentials to examine SG differences in AUD will be covered. Overall, current research on the neuroimaging of AUD, alcohol consumption, or risk of AUD is limited, and findings are mixed regarding the effect of SG on neurochemical, structural, and functional mechanisms associated with AUD. We address SG disparities in the neuroimaging of AUD and propose a call to action to include women in brain imaging research. Future studies are crucial to our understanding of the neurobiological underpinnings of AUD across neural systems and the vulnerability for AUD among women and men.

Accuracy of self-reported hypertension: Effect of age, gender, and history of alcohol dependence

Patient awareness of medical conditions may influence treatment seeking and monitoring of these conditions. Accurate awareness of hypertension reported to clinicians evaluating patients for whom clinical history is limited, such as in emergency care, can aid in diagnosis by revealing whether measured hypertension is typical or atypical. Measurement of blood pressure in a laboratory study was assessed at rest, immediately before phlebotomy, and within 10 minutes after. The resting measure was used to determine the accuracy of self-reported hypertension in 283 adults. Parametric analyses were conducted to identify potential variables influencing accuracy of self-reported hypertension. Sensitivity, specificity, and the kappa coefficient of agreement were calculated to determine the influence of alcohol dependence (AD), sex, age, and cigarette smoking on hypertension awareness. Self-report was mildly sensitive, correctly identifying individuals with hypertension in approximately 37% of the cases, but was highly specific (95%) in identifying individuals without hypertension. Similar sensitivities were found in analyses separated by sex. Sensitivity was greater in those over age 55 (53%) in comparison with those <54, as well as in those who were not smoking. Comparison of those with and without a history of AD revealed that both groups show similar accuracy in reporting hypertension. Absence of hypertension can be accurately determined with self-report data in those without hypertension. A significant proportion of those with measured hypertension report an absence of hypertension.

The effect of a clinical decision support system on prompting an intervention for risky alcohol use in a primary care smoking cessation program: a cluster randomized trial

Background

Clinical decision support systems (CDSSs) may promote practitioner adherence to evidence-based guidelines. This study examined if the addition of a CDSS influenced practitioner delivery of a brief intervention with treatment-seeking smokers who were drinking above recommended alcohol consumption guidelines, compared with practitioners who do not receive a CDSS prompt.

Methods

This was a cluster randomized controlled trial conducted in primary health care clinics across Ontario, Canada, implementing the Smoking Treatment for Ontario Patients (STOP) smoking cessation program. Clinics randomized to the intervention group received a prompt when a patient reported consuming alcohol above the Canadian Cancer Society (CCS) guidelines; the control group did not receive computer alerts. The primary outcome was an offer of an appropriate educational alcohol resource, an alcohol reduction workbook for patients drinking above the CCS guidelines, and an abstinence workbook to patients scoring above 20 points in the AUDIT screening tool; the secondary outcome was patient acceptance of the resource. The tertiary outcome was patient abstinence from smoking, and alcohol consumption within CCS guidelines, at 6-month follow-up. Results were analyzed using a generalized estimation approach for fitting logistic regression using a population-averaged method.

Results

Two hundred and twenty-one clinics across Ontario were randomized for this study; 110 to the intervention arm and 111 to the control arm. From the 15,222 patients that enrolled in the smoking cessation program, 15,150 (99.6% of patients) were screened for alcohol use and 5715 patients were identified as drinking above the CCS guidelines. No statistically significant difference between groups was seen in practitioner offer of an educational alcohol resource to appropriate patients (OR = 1.19, 95% CI 0.88–1.64, p = 0.261) or in patient abstinence from smoking and drinking within the CCS guidelines at 6-month follow-up (OR = 0.93, 95% CI 0.71–1.22, p = 0.594). However, a significantly greater proportion of patients in the intervention group accepted the alcohol resource offered to them by their practitioner (OR = 1.48, 95% CI 1.01–2.16, p = 0.045).

Conclusion

A CDSS may not increase the likelihood of practitioners offering an educational alcohol resource, though it may have influenced patients’ acceptance of the resource.

Trial registration

This trial is registered with ClinicalTrials.gov, number NCT03108144, registered on April 11, 2017, “retrospectively registered”.

Electronic supplementary material

The online version of this article (10.1186/s13012-019-0935-x) contains supplementary material, which is available to authorized users.

Regional Brain Volume Changes in Alcohol-Dependent Individuals During Short-Term and Long-Term Abstinence

BACKGROUND

Widespread brain atrophy in alcohol-dependent individuals (ALC) has been consistently documented in pathological and magnetic resonance imaging (MRI) studies. Longitudinal MRI studies have shown that the regional brain volume losses in ALC are partially reversible during abstinence from alcohol. The goal of this study was to determine volume reductions in cortical and subcortical regions functionally important to substance use behavior and their changes during short-term (1 week to 1 month) and long-term abstinence (1 to 7 months) from alcohol. The regions of interest (ROIs) were as follows: anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex (OFC), insula, amygdala, and hippocampus.

METHODS

A total of 85 unique ALC were assessed at 1 week (n = 65), 1 month (n = 82), and 7 months (n = 36) of abstinence. In addition, 17 light/nondrinking healthy controls (CON) were assessed at baseline and follow-up over a 10-month interval. Regional brain volumes were derived from FreeSurfer. Cross-sectional statistical analyses using 1-way analysis of variance or Fisher's exact test were applied to identify group differences. Longitudinal statistical analyses using linear mixed models were applied to identify regional volume increases and nonlinear volume recovery trajectories.

RESULTS

We demonstrated significant regional volume reductions in ACC, DLPFC, and hippocampus. Older age was associated with smaller DLPFC and OFC, and higher average monthly drinking over 1 year prior to study was associated with smaller OFC. We also demonstrated significant volume increases of all ROIs except amygdala in ALC and significant nonlinear volume recovery trajectories of DLPFC, OFC, and insula.

CONCLUSIONS

Results showed significant volume reductions in key regions of the executive control, salience, and emotion networks in ALC at entry into treatment and significant volume increases during short-term and long-term abstinence that were nonlinear over the entire abstinence period for the DLPFC, OFC, and insula. This gray matter plasticity during alcohol abstinence may have important neurobiological and neurocognitive implications in ALC, and it may contribute to an individual's ability to maintain abstinence from alcohol at different phases.

Differences in White Matter Microstructure and Connectivity in Nontreatment-Seeking Individuals with Alcohol Use Disorder

BACKGROUND

Diffusion-weighted imaging (DWI) has been widely used to investigate the integrity of white matter (WM; indexed by fractional anisotropy [FA]) in alcohol dependence and cigarette smoking. These disorders are highly comorbid, yet cigarette use has often not been adequately controlled in neuroimaging studies of alcohol-dependent populations. In addition, information on WM deficits in currently drinking, nontreatment-seeking (NTS) individuals with alcohol dependence is limited. Therefore, the aim of this work was to investigate WM microstructural integrity in alcohol use disorder by comparing matched samples of cigarette smoking NTS and social drinkers (SD).

METHODS

Thirty-eight smoking NTS and 19 smoking SD subjects underwent DWI as well as structural magnetic resonance imaging. After an in-house preprocessing of the DWI data, FA images were analyzed with tract-based spatial statistics (TBSS). FA obtained from the TBSS skeleton was tested for correlation with recent alcohol consumption.

RESULTS

Smoking NTS had lower FA relative to smoking SD, predominantly in the left hemisphere (p < 0.05, family-wise error rate corrected across FA skeleton). Across the full sample, FA and number of drinks per week were negatively related (ρ = -0.348, p = 0.008). Qualitative analyses of the structural connections through compromised WM as identified by TBSS showed differential connectivity of gray matter in NTS compared to SD subjects of left frontal, temporal, and parietal regions.

CONCLUSIONS

NTS subjects had lower WM FA than SD, indicating compromised WM integrity in the NTS population. The inverse relationship of entire WM skeleton FA with self-reported alcohol consumption supports previous evidence of a continuum of detrimental effects of alcohol consumption on WM. These results provide additional evidence that alcohol dependence is associated with reduced WM integrity in currently drinking NTS alcohol-dependent individuals, after controlling for the key variable of cigarette smoking.

Combining alcohol interventions with tobacco addictions treatment in primary care-the COMBAT study: a pragmatic cluster randomized trial

BACKGROUND

Tobacco and alcohol use present multiplicative risk for aerodigestive cancers. Reducing alcohol consumption improves smoking cessation outcomes and reduces cancer risk. Risky alcohol consumption and smoking are often treated separately despite concurrent treatment potentially leading to better outcomes for each. However, no rapidly scalable program exists for combined interventions in primary care clinics spread across wide geographic areas. This cluster randomized trial aims to report on the effects of a novel clinical decision support system (CDSS) on intervention rates by primary care practitioners addressing risky alcohol use in a smoking cessation program.

METHODS/DESIGN

We will be implementing a clinical decision support system (CDSS) in 221 primary care sites participating in the Smoking Treatment for Ontario Patients (STOP) program across Ontario, Canada. Sites will be blindly allocated to one of two clinical decision support systems guiding practitioners to provide a risky alcohol use intervention to smokers attempting to quit using nicotine replacement therapy (NRT). Risky alcohol use is defined as drinking above the Canadian Cancer Society's low-risk drinking guidelines. Primary analysis will measure the proportion of risky drinkers offered an alcohol intervention in each CDSS arm at baseline. Patients will be contacted by phone or email to track smoking cessation and alcohol consumption rates at 6- and 12-month follow-up.

DISCUSSION

Upon completion of the trial, the effect of different clinical decision support systems on practitioner behaviour, and on client tobacco and alcohol use, will be discussed. If the CDSS successfully promotes SBIRT for risky alcohol use in a primary care setting and/or improves patient-level outcomes, including smoking cessation rates and alcohol use reduction, this tool can be used as a model for other web-based behaviour change interventions integrated into primary care practice.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03108144.

The Differential Effects of Alcohol and Nicotine-Specific Nitrosamine Ketone on White Matter Ultrastructure

Aims

The chronic consumption of alcohol is known to result in neurodegeneration and impairment of cognitive function. Pathological and neuroimaging studies have confirmed that brain atrophy in alcoholics is mainly due to widespread white matter (WM) loss with neuronal loss restricted to specific regions, such as the prefrontal cortex. Neuroimaging studies of cigarette smokers also suggest that chronic inhalation of tobacco smoke leads to brain atrophy, although the neurotoxic component is unknown. As a high proportion of chronic alcoholics also smoke cigarettes it has been hypothesized that at least some alcohol-related brain damage is due to tobacco smoke exposure.

Methods

39 Long Evans rats were subjected to 8 weeks exposure to alcohol and/or 5 weeks co-exposure to nicotine-specific nitrosamine ketone (NNK), a proxy for tobacco smoke. Their frontal WM was then assayed with transmission electron microscopy.

Results

NNK and ethanol co-exposure had a synergistic effect in decreasing myelinated fibre density. Furthermore, NNK treatment led to a greater reduction in myelin sheath thickness than ethanol whereas only the ethanol-treated animals showed a decrease in unmyelinated fibre density.

Conclusion

These data suggest that NNK causes WM degeneration, an effect that is exacerbated by alcohol, but unlike alcohol, it has little impact on the neuronal components of the brain.

Structural Neuroimaging in Polysubstance Users

The simultaneous and/or concurrent use of licit and illicit substances (polysubstance use, PSU) is most common today. Structural magnetic resonance imaging (MRI) has been applied extensively to study individuals ostensibly using a single substance. These studies have produced a picture of regional gray matter and white matter alterations with each substance or class of substances. Very few studies measured regional brain morphometry in today's polysubstance users. This limited data suggest morphometric alterations with PSU that are not simply additive but often different from those of monosubstance users. Specifically, subcortical volume enlargements are observed that may be tied to mechanisms that also oppose volume reductions in cortical brain regions, thereby underestimating actual cortical atrophy. The complex actions of polysubstance use on brain structure and function need greater scrutiny with strong methodological approaches to inform more efficient treatment of polysubstance users.

Severity of alcohol dependence is negatively related to hypothalamic and prefrontal cortical gray matter density in heavy drinking smokers

BACKGROUND

While research has examined brain structure in individuals who use alcohol or nicotine, heavy drinking smokers comprise a unique subpopulation of substance users for whom less is known about the relationship between alcohol or nicotine use and structural brain abnormalities.

OBJECTIVES

The present study examined gray matter morphometry in a sample of 39 heavy drinking smokers (24 males, 15 females) in relation to alcohol and nicotine dependence and quantity of use.

METHODS

Traditional voxel-based morphometry techniques were employed for preprocessing of imaging data. One multiple regression analysis for alcohol and nicotine dependence severity and another for alcohol and nicotine quantity of use were conducted, while controlling for age, gender, and total intracranial volume (ICV).

RESULTS

Alcohol dependence severity was significantly negatively associated with gray matter density in the hypothalamus (p < 0.001, uncorrected) and the right superior frontal gyrus (p < 0.001, uncorrected), while controlling for nicotine dependence severity, age, gender, and ICV. There were no significant relationships observed with respect to nicotine dependence severity, the quantity of alcohol use, or the quantity of nicotine use variables and gray matter density.

CONCLUSIONS

These findings suggest that within heavy drinking smokers, alcohol dependence severity is significantly related to alterations in brain structure, while this effect is not seen for the quantity of alcohol or nicotine use, or severity of nicotine dependence. The current findings help clarify the contribution of alcohol and nicotine effects on brain structure, which could aid in understanding their neurocognitive consequences in heavy drinking smokers.

The effects of chronic smoking on the pathology of alcohol-related brain damage

Both pathological and neuroimaging studies demonstrate that chronic alcohol abuse causes brain atrophy with widespread white matter loss limited gray matter loss. Recent neuroimaging studies suggest that tobacco smoking also causes brain atrophy in both alcoholics and neurologically normal individuals; however, this has not been confirmed pathologically. In this study, the effects of smoking and the potential additive effects of concomitant alcohol and tobacco consumption were investigated in autopsied human brains. A total of 44 cases and controls were divided into four groups: 16 non-smoking controls, nine smoking controls, eight non-smoking alcoholics, and 11 smoking alcoholics. The volumes of 26 gray and white matter regions were measured using an established point-counting technique. The results showed trends for widespread white matter loss in alcoholics (p < 0.007) but no effect on gray matter regions. In contrast, smoking alone had no effect on brain atrophy and the combination of smoking and alcohol showed no additional effect. Neuronal density was analyzed as a more sensitive assay of gray matter integrity. Similar to the volumetric analysis, there was a reduction in neurons (29%) in the prefrontal cortex of alcoholics, albeit this was only a trend when adjusted for potential confounders (p < 0.06). There were no smoking or combinatorial effects on neuronal density in any of the three regions examined. These results do not support the hypothesis that smoking exacerbates alcohol-related brain damage. The trends here support previous studies that alcohol-related brain damage is characterized by focal neuronal loss and generalized white matter atrophy. These disparate effects suggest that two different pathogenic mechanisms may be operating in the alcoholic brain. Future studies using ultrastructural or molecular techniques will be required to determine if smoking has more subtle effects on the brain and how chronic alcohol consumption leads to widespread white matter loss.

Nicotine impact on the structure of adult male guinea pig auditory cortex

BACKGROUND

A growing body of evidence suggests that chronic cigarette smoking causes detrimental effects on brain morphology.

AIM OF WORK

To study the structural changes in auditory cortex region (Layer V), under the influence of nicotine.

MATERIAL AND METHODS

Three animal groups (10 each) were used; group I (control) and groups IIa and IIb received 3 and 6mg/kg nicotine respectively. The specimens from the auditory cortex were examined using light and electron microscopy and morphometry.

RESULTS

Neurons and blood capillaries of the auditory cortex (layer V), were influenced by chronic nicotine treatment in a dose dependent manner. The neurons and their processes revealed disorganization and dissociation of microtubules. The neuronal cells nucleoli characteristically revealed large fibrillar centers detected by silver stain and ultrastructure. The blood capillaries revealed collapse, irregular lumen, thickened basal lamina, abnormal forms of nuclei and organization of microtubules. Neuroglia revealed marked reactivity. Morphometrically, there was a significant decrease in the thickness of the auditory cortex and the number of light neurons and a significant increase in the number of dark neurons in comparison to the control.

CONCLUSION

Nicotine affects the integrity of the auditory cortex possibly by reducing metabolic and transcription activities.

Cigarette Smoking and Risk of Alcohol Use Relapse Among Adults in Recovery from Alcohol Use Disorders

BACKGROUND

Individuals in recovery from alcohol use disorders (AUDs) frequently continue to smoke cigarettes. The purpose of this study was to examine the relationship between cigarette smoking status and risk of AUD relapse in adults with remitted AUDs among adults in the United States.

METHODS

Data were drawn from Wave 1 (2001 to 2002) and Wave 2 (2004 to 2005) of the National Epidemiologic Survey on Alcohol and Related Conditions. Analyses included the subsample of respondents who completed both waves of data collection reported a history of alcohol abuse and/or dependence prior to Wave 1 (N = 9,134). Relationships between Wave 1 cigarette smoking status (nonsmoker, daily cigarette smoker, and nondaily cigarette smoker) and Wave 2 alcohol use, abuse, and dependence were examined using logistic regression analyses. Analyses were adjusted for Wave 1 demographics; mood, anxiety, and substance use disorders; nicotine dependence; and AUD severity.

RESULTS

Both daily and nondaily cigarette smoking at Wave 1 were significantly associated with a lower likelihood of alcohol use and a greater likelihood of alcohol abuse and dependence at Wave 2 compared to Wave 1 nonsmoking. These relationships remained significant after adjusting for demographics, psychiatric disorders, substance use disorders, AUD severity, and nicotine dependence.

CONCLUSIONS

Among adults with remitted AUDs, daily and nondaily use of cigarettes was associated with significantly decreased likelihood of alcohol use and increased likelihood of alcohol abuse and alcohol dependence 3 years later. Concurrent treatment of cigarette smoking when treating AUDs may help improve long-term alcohol outcomes and reduce the negative consequences of both substances.

Serial longitudinal magnetic resonance imaging data indicate non-linear regional gray matter volume recovery in abstinent alcohol-dependent individuals

The trajectory of regional volume changes during the first year of sustained abstinence in those recovering from an alcohol use disorder is unclear because previous research typically employed only two assessment points. To better understand the trajectory of regional brain volume recovery in treatment-seeking alcohol-dependent individuals (ALC), regional brain volumes were measured after 1 week, 1 month and 7.5 months of sustained abstinence via magnetic resonance imaging at 1.5 T. ALC showed significant volume increases in frontal, parietal and occipital gray matter (GM) and white matter (WM), total cortical GM and total lobar WM, thalamus and cerebellum, and decreased ventricular volume over 7.5 months of abstinence. Volume increases in regional GM were significantly greater over 1 week to 1 month than from 1 month to 7.5 months of abstinence, indicating a non-linear rate of change in regional GM over 7.5 months. Overall, regional lobar WM showed linear volume increases over 7.5 months. With increasing age, smoking ALC showed lower frontal and total cortical GM volume recovery than non-smoking ALC. Despite significant volume increases, ALC showed smaller GM volumes in all regions, except the frontal cortex, than controls after 7.5 months of abstinence. ALC and controls showed no regional WM volume differences at any assessment point. In non-smoking ALC only, increasing regional GM and WM volumes were related to improving processing speed. Findings may indicate a differential rate of recovery of cell types/cellular components contributing to GM and WM volume during early abstinence, and that GM volume deficits persist after 7.5 months of sustained sobriety in this ALC cohort.

Heavy-Drinking Smokers' Treatment Needs and Preferences: A Mixed-Methods Study

The purpose of this mixed methods study was to describe the smoking and psychological characteristics of heavy-drinking smokers, their perceptions of smoking and drinking, and their smoking and alcohol treatment preferences to inform an integrated smoking and alcohol intervention. Heavy-drinking smokers (N=26) completed standardized surveys and participated in semi-structured focus group interviews. Participants reported a strong association between their smoking and drinking. Participants were more motivated to quit smoking than to reduce their drinking but perceived greater barriers to smoking cessation. Stress/negative affect was closely linked with both behaviors. They expressed overall enthusiasm for a smoking and alcohol intervention but had specific format and content preferences. Half preferred an integrated treatment format whereas others preferred a sequential treatment model. The most preferred content included personalized health feedback and a way to monitor health gains after behavior changes.

Cigarette smoking and thinning of the brain's cortex

Cigarette smoking is associated with cognitive decline and dementia, but the extent of the association between smoking and structural brain changes remains unclear. Importantly, it is unknown whether smoking-related brain changes are reversible after smoking cessation. We analyzed data on 504 subjects with recall of lifetime smoking data and a structural brain magnetic resonance imaging at age 73 years from which measures of cortical thickness were extracted. Multiple regression analyses were performed controlling for gender and exact age at scanning. To determine dose-response relationships, the association between smoking pack-years and cortical thickness was tested and then repeated, while controlling for a comprehensive list of covariates including, among others, cognitive ability before starting smoking. Further, we tested associations between cortical thickness and number of years since last cigarette, while controlling for lifetime smoking. There was a diffuse dose-dependent negative association between smoking and cortical thickness. Some negative dose-dependent cortical associations persisted after controlling for all covariates. Accounting for total amount of lifetime smoking, the cortex of subjects who stopped smoking seems to have partially recovered for each year without smoking. However, it took ~25 years for complete cortical recovery in affected areas for those at the mean pack-years value in this sample. As the cortex thins with normal aging, our data suggest that smoking is associated with diffuse accelerated cortical thinning, a biomarker of cognitive decline in adults. Although partial recovery appears possible, it can be a long process.

Alcohol use disorder with and without stimulant use: brain morphometry and its associations with cigarette smoking, cognition, and inhibitory control

OBJECTIVE

Little is known about the effects of polysubstance use and cigarette smoking on brain morphometry. This study examined neocortical brain morphometric differences between abstinent polysubstance dependent and alcohol-only dependent treatment seekers (ALC) as well as light drinking controls (CON), the associations of cigarette smoking in these polysubstance users (PSU), and morphometric relationships to cognition and inhibitory control.

METHODS

All participants completed extensive neuropsychological assessments and 4 Tesla brain magnetic resonance imaging. PSU and ALC were abstinent for one month at the time of study. Parcellated morphological data (volume, surface area, thickness) were obtained with FreeSurfer methodology for the following bilateral components: dorso-prefrontal cortex (DPFC), anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), and insula. Regional group differences were examined and structural data correlated with domains of cognition and inhibitory control.

RESULTS

PSU had significantly smaller left OFC volume and surface area and trends to smaller right DPFC volume and surface area compared to CON; PSU did not differ significantly from ALC on these measures. PSU, however, had significantly thinner right ACC than ALC. Smoking PSU had significantly larger right OFC surface area than non-smoking PSU. No significant relationships between morphometry and quantity/frequency of substance use, alcohol use, or age of onset of heavy drinking were observed. PSU exhibited distinct relationships between brain structure and processing speed, cognitive efficiency, working memory and inhibitory control that were not observed in ALC or CON.

CONCLUSION

Polysubstance users have unique morphometric abnormalities and structure-function relationships when compared to individuals dependent only on alcohol and light drinking controls. Chronic cigarette smoking is associated with structural brain irregularities in polysubstance users. Further elucidation of these distinctive characteristics could help inform the development of targeted and thus potentially more effective treatments in this large but understudied population.

Altered human brain anatomy in chronic smokers: a review of magnetic resonance imaging studies

Cigarette smoking is becoming more prevalent in developing countries, such as China, and is the largest single cause of preventable death worldwide. New emerging reports are highlighting how chronic cigarette smoking plays a role in neural dysfunctions, such as cognitive decline. Basic animal experimental studies have shown that rats undergo persistent pathological brain changes after being given chronic levels of nicotine. What is perhaps less appreciated is the fact that chronic cigarette smoking induces subtle anatomical changes in the human brain. Consequently, this chapter aims to summarize and integrate the existing magnetic resonance imaging studies on both gray- and white-matter marcostructural and microstructural changes. The reviewed studies demonstrate that chronic cigarette smoking results in discrete and localized alterations in brain region tissue (both the gray and white matter of different brain regions), which may, in part, be responsible for different neural dysfunctions. In addition, we further discuss the possible pathological and neurobiological mechanisms of these nicotinic effects on the brain tissue. We will also address the limitations of the current studies on this issue and identify opportunities for future research.

Pharmacological Options for Smoking Cessation in Heavy-Drinking Smokers

There is a high prevalence of comorbid tobacco use and alcohol use disorder (AUD), affecting more than 6 million people in the US. Globally, tobacco and alcohol use rank fourth and fifth, respectively, for disability-adjusted life-years lost. Levels of alcohol use are higher in smokers than nonsmokers, and the prevalence of smoking is higher in heavy drinkers compared with nondrinkers. This relationship is driven by many different factors, including genetics, neurobiological mechanisms, conditioning processes, and psychosocial influences. Although this unique population tends to experience more negative health consequences, more severe AUD, and poorer response to treatment than those with either AUD or tobacco use disorder alone, there are currently no available treatment protocols tailored to this comorbid condition. In this review, we provide a comprehensive review of ongoing clinical research into smoking cessation options for heavy-drinking smokers (HDS) through an evaluation of the effect of promising novel pharmacotherapies as well as combination therapies, including varenicline, naltrexone, the combination of varenicline and naltrexone, and the combination of naltrexone and nicotine replacement therapy (NRT). These treatments are considered in light of the standard of care for smoking cessation, and seek to improve upon the available guidelines for this sizeable subgroup of smokers, namely those smokers who drink heavily.

Varenicline, low dose naltrexone, and their combination for heavy-drinking smokers: human laboratory findings

RATIONALE

Heavy-drinking smokers constitute a sizeable and hard-to-treat subgroup of smokers, for whom tailored smoking cessation therapies are not yet available.

OBJECTIVES

The present study used a double-blind, randomized, 2 × 2 medication design, testing varenicline alone (VAR; 1 mg twice daily), low dose naltrexone alone (L-NTX; 25 mg once daily), varenicline plus naltrexone, and placebo for effects on cigarette craving and subjective response to alcohol and cigarettes in a sample (n = 130) of heavy-drinking daily smokers (≥10 cigarettes/day).

METHODS

All participants were tested after a 9-day titration period designed to reach a steady state on the target medication. Testing was completed at 12 h of nicotine abstinence, after consuming a standard dose of alcohol (target breath alcohol concentration = 0.06 g/dl) and after smoking the first cigarette of the day.

RESULTS

The combination of VAR + L-NTX was superior to placebo, and at times superior to monotherapy, in attenuating cigarette craving, cigarette and alcohol "high," and in reducing ad-lib consumption of both cigarettes and alcohol during the 9-day medication titration period.

CONCLUSIONS

These preliminary findings indicate that clinical studies of the combination of VAR + L-NTX for heavy drinkers trying to quit smoking are warranted and may ultimately improve clinical care for this sizeable and treatment-resistant subgroup of smokers.

Decision-making deficits in patients diagnosed with disordered gambling using the Cambridge Gambling task: the effects of substance use disorder comorbidity

BACKGROUND

Disordered gambling (DG) has often been associated with impaired decision-making abilities, suggesting a dysfunction in the ventromedial prefrontal cortex (vmPFC).

AIMS

To our knowledge, no previous study has accurately considered the effect of substance use disorder (SUD) comorbidity (including nicotine dependence) on decision-making impairments in DG.

METHODS AND MATERIALS

We employed the Cambridge Gambling Task (CGT) to assess a big cohort of patients diagnosed with DG (N = 80) against matched healthy controls (HCs) (N = 108). The cohort included DG patients with nicotine and alcohol dependence, alcohol dependence only and 12 "pure" nonsmokers with only DG diagnosis.

RESULTS

Pure nonsmoking, nicotine dependent as well as alcoholic DGs with current nicotine dependence, demonstrated a decision making profile, characterized by poor decision-making abilities and failure to make right choices (rational), closely resembling that of patients with vmPFC damage.

DISCUSSION

This suggests that DGs with and without SUD comorbidity are equally affected in that domain of decision making abilities. Additionally, gambling diagnosis combined with alcohol and nicotine dependence involves a group of gambling patients with a relatively riskier decision making profile, showing that these patients apart from making irrational decisions take also more risks. Our findings highlight the importance of accounting for SUD comorbidities with useful implications for future research and therapy. Limitations of the current investigation are discussed.

Varenicline, naltrexone, and their combination for heavy-drinking smokers: preliminary neuroimaging findings

RATIONALE

Heavy drinking smokers constitute a sizeable and hard-to-treat subgroup of smokers, for whom tailored smoking cessation therapies are not yet available.

OBJECTIVE

The present study used a double-blind, randomized, 2 × 2 medication design, testing varenicline alone (VAR; 1 mg twice daily), naltrexone alone (NTX; 25 mg once daily), varenicline plus naltrexone, and placebo for effects on neural activation to cigarette cues in a sample (n = 40) of heavy drinking daily smokers (≥10 cigarettes/day).

METHODS

All participants were tested after a 10-12-day titration period designed to reach steady state on the target medication. Participants underwent functional neuroimaging (fMRI) for examination of brain responses to visual smoking-related (vs. neutral) cues.

RESULTS

Region of interest (ROI) analyses of brain responses to Cigarette vs. Neutral Cues indicated that the combination of VAR + NTX was associated with reduced activation of the bilateral anterior cingulate cortex as compared to placebo and to NTX alone. Exploratory whole-brain analyses also indicated significant differences in brain activation during cigarette cues in the active medications versus placebo condition. All medications suppressed left nucleus accumbens activation relative to placebo, suggesting the possibility that both medications, either alone or in combination, reduce neural signals associated with appetitive behavior.

CONCLUSIONS

Although preliminary, these neuroimaging findings indicate that clinical studies of the combination of VAR + NTX for heavy drinkers trying to quit smoking may be warranted.

White matter volume in alcohol use disorders: a meta-analysis

Atrophy of brain white matter (WM) often is considered a signature injury of alcohol use disorders (AUDs). However, investigations into AUD-related changes in WM volume have yielded complex findings that are difficult to synthesize in a narrative review. The objective of this study was to obtain an averaged effect size (ES) for WM volume reduction associated with AUD diagnosis and to test potential moderators of ES. Study inclusion criteria were: (1) English language; (2) peer reviewed; (3) published before December 2011; (4) use of magnetic resonance imaging (MRI); (5) human participants; (6) inclusion of AUD group; (7) inclusion of non-AUD comparison group; and (8) reporting or testing of total or cerebral WM volume. Moderators included study design, MRI methodology and AUD characteristics. Nineteen studies with a total of 1302 participants (70% male) were included, and calculated ESs were confirmed by the corresponding author for 12 studies. The magnitude of the averaged ES adjusted for small sample bias (Hedges' g) for WM reduction in AUDs was 0.304 (standard error = 0.134, range = -0.57-1.21). Hierarchical linear modeling indicated that the overall ES differed significantly from 0, t(18) = 2.257, P = 0.037, and that the distribution of the 19 ESs showed significant heterogeneity beyond sampling error, χ(2) (18) = 52.400, P < 0.001. Treatment-seeking status and length of abstinence were significant moderators of ES distribution. These results are suggestive of WM recovery with sustained abstinence and point to the need for further investigation of factors related to treatment-seeking status.

Brain structure in adolescents and young adults with alcohol problems: systematic review of imaging studies

AIMS

Alcohol-dependent people who are middle-aged or older have a widespread loss of cortical grey and white matter, particularly in the prefrontal cortex (PFC). We examine if brain abnormalities are detectable in alcohol use disorders before the fifth decade (i.e., <40), and the brain structural differences associated with alcohol abuse/dependence in adolescence.

METHODS

Case-control studies comparing brain structure in alcohol-abusing/-dependent individuals with normal controls in which the mean age of participants was <40 were identified using Medline, EMBASE and PsychInfo. Studies in which mean age was over and under 21 were considered separately.

RESULTS

Twelve papers fulfilled inclusion criteria, five in the adolescent (14-21) and seven in the young adult age range. Two independent groups reported hippocampal and prefrontal volume reductions in adolescents, although this was consistently observed only in females. In young adults (aged 21-40), there were grey matter deficits in the PFC in both sexes. Adult women appeared to, particularly, exhibit white matter differences, evident as reduced area of the corpus callosum. Hippocampal volume reduction was observed in one study of young adults study but not another.

CONCLUSION

The available data suggest that quantitative structural abnormalities of the brain are detectable in young alcohol abusers. There is overlap between the abnormalities seen in adolescents and young adults, although hippocampal volume loss is most consistently seen in the former group. The adolescent hippocampus may be particularly susceptible to alcohol, potentially because of an interaction between adolescent brain development and alcohol exposure.

Brain volumes and neuropsychological performance are related to current smoking and alcoholism history

BACKGROUND

Dual dependence on alcohol and nicotine is common, with many reports suggesting that more than 80% of alcoholics also smoke cigarettes. Even after cessation of alcohol consumption, many recovering alcoholics continue to smoke. In this exploratory study, we examined how current smoking and a history of alcoholism interacted in relation to brain volumes and neuropsychological performance.

METHODS

Participants were 14 abstinent long-term alcoholics (seven current smokers and seven nonsmokers), and 13 nonalcoholics (six current smokers and seven nonsmokers). The groups were equivalent in age, gender, education, and intelligence quotient. Two multiecho magnetization-prepared rapid acquisition with gradient echo (MP-RAGE) scans were collected for all participants using a 3T magnetic resonance imaging scanner with a 32 channel head coil. Brain volumes for each gray and white matter region of interest were derived using FreeSurfer. Participants completed a battery of neuropsychological tests measuring intelligence quotient, memory, executive functions, personality variables, and affect.

RESULTS

COMPARED TO NONSMOKING NONALCOHOLICS, ALCOHOLICS WHO SMOKE (THE COMORBID GROUP) HAD VOLUMETRIC ABNORMALITIES IN: pre- and para-central frontal cortical areas and rostral middle frontal white matter; parahippocampal and temporal pole regions; the amygdala; the pallidum; the ventral diencephalic region; and the lateral ventricle. The comorbid group performed worse than nonsmoking nonalcoholics on tests of executive functioning and on visually-based memory tests. History of alcoholism was associated with higher neuroticism scores among smokers, and current smoking was associated with higher sensation seeking scores and lower extraversion scores among nonalcoholics.

CONCLUSION

Results from this exploratory study support and extend prior reports showing that alcoholism and smoking, alone and in combination, are associated with structural brain abnormalities and poorer performance on neuropsychological tests. Therefore, it is important to consider smoking status in alcoholism studies and vice versa.

Sex differences in decreased limbic and cortical grey matter volume in cocaine dependence: a voxel-based morphometric study

Structural neuroimaging studies have provided evidence of differences in local brain volume between cocaine-dependent and healthy control individuals. While sex differences in aetiology, course and brain dysfunction associated with chronic cocaine abuse have been previously documented, evidence of sex-specific differences in brain volume has not been examined thus far. This study examined sex-related differences in grey matter volume between cocaine-dependent and healthy control subjects using voxel-based morphometry. High-resolution T1 structural scans were obtained from 36 inpatient, treatment-engaged 3-week abstinent cocaine-dependent (CD) individuals. Fifty healthy control subjects were also scanned. Segmentation and registration were performed in SPM8, using New Segment and DARTEL, respectively. The whole-brain statistical analysis was conducted in SPM8 using random field-based cluster-size testing and family-wise error rate correction for multiple comparisons. CD patients were found to have less grey matter volume in anterior prefrontal cortex, including frontopolar and orbitofrontal cortices, and a posterior region surrounding the parietal-occipital sulcus. Female CD patients had less grey matter volume than female controls in left inferior frontal gyrus, insula, superior temporal gyrus and hippocampus. Male CD patients had less grey matter in a superior cortical region that included the precentral gyrus and the mid-cingulate. These sex differences in lower grey matter volume add to the evidence from functional neuroimaging for sex-specific differences in the neurophysiological changes associated with chronic cocaine use.

Gray-matter volume in methamphetamine dependence: cigarette smoking and changes with abstinence from methamphetamine

BACKGROUND

Group differences in brain structure between methamphetamine-dependent and healthy research participants have been reported, but findings in the literature present discrepancies. Although most methamphetamine-abusing individuals also smoke cigarettes, the effects of smoking on brain structure have not been distinguished from those of methamphetamine. Changes with abstinence from methamphetamine have also been relatively unexplored. This study, therefore, attempted to account for effects of smoking and brief abstinence from methamphetamine on gray-matter measures in methamphetamine-dependent research participants.

METHODS

Gray matter was measured using voxel-based morphometry in three groups: 18 control nonsmokers, 25 control smokers, and 39 methamphetamine-dependent smokers (methamphetamine-abstinent 4-7 days). Subgroups of methamphetamine-dependent and control participants (n=12/group) were scanned twice to determine change in gray matter over the first month of methamphetamine abstinence.

RESULTS

Compared with Control Nonsmokers, Control Smokers and Methamphetamine-dependent Smokers had smaller gray-matter volume in the orbitofrontal cortex and caudate nucleus. Methamphetamine-dependent Smokers also had smaller gray-matter volumes in frontal, parietal and temporal cortices than Control Nonsmokers or Smokers, and smaller gray-matter volume in insula than control nonsmokers. Longitudinal assessment revealed gray matter increases in cortical regions (inferior frontal, angular, and superior temporal gyri, precuneus, insula, occipital pole) in methamphetamine-dependent but not control participants; the cerebellum showed a decrease.

CONCLUSIONS

Gray-matter volume deficits in the orbitofrontal cortex and caudate of methamphetamine-dependent individuals may be in part attributable to cigarette smoking or pre-morbid conditions. Increase in gray matter with methamphetamine abstinence suggests that some gray-matter deficits are partially attributable to methamphetamine abuse.

A voxel-based morphometry study comparing problem gamblers, alcohol abusers, and healthy controls

BACKGROUND

Alcohol use disorders (AUDs) are associated with smaller grey matter volumes in cortical and subcortical brain regions which are related to cognitive impairments often found in these disorders. Similar cognitive impairments have been found in patients suffering from problem gambling behaviour. However, in contrast to AUDs, gambling behaviour does not entail brain exposure to toxic agents. Although there are many clinical, neuropsychological, and neurobiological similarities between PG and substance use disorders it has not yet been established whether pathological gambling, similar to alcohol use disorders, is associated with abnormal regional grey matter volumes.

METHODS

With whole-brain voxel-based morphometry we compared a group of 40 treatment seeking problem gamblers, 36 subjects with an alcohol use disorder, and 54 healthy controls to evaluate potential group differences in regional grey matter volumes, corrected for age, IQ, smoking status, and total intracranial volume (TIV).

RESULTS

Significantly smaller grey matter volumes in left superior frontal cortex, left precentral cortex, right insula, right putamen, left thalamus, bilateral superior parietal cortex and right supramarginal cortex were present in subjects with an alcohol use disorder compared to healthy controls and problem gamblers. No significant grey matter volume differences were present between problem gamblers and healthy controls.

CONCLUSION

In conclusion, we replicated previous findings of smaller grey matter volumes in subjects with an alcohol use disorder and found no significant morphological brain abnormalities in problem gamblers.

Cigarette smoking and white matter microstructure in schizophrenia

The majority of patients with schizophrenia smoke cigarettes. Both nicotine use and schizophrenia have been associated with alterations in brain white matter microstructure as measured by diffusion tensor imaging (DTI). The purpose of this study was to examine fractional anisotropy (FA) in smoking and non-smoking patients with schizophrenia and in healthy volunteers. A total of 43 patients (28 smoking and 15 non-smoking) with schizophrenia and 40 healthy, non-smoking participants underwent DTI. Mean FA was calculated in four global regions of interest (ROIs) (whole brain, cerebellum, brainstem, and total cortical) as well as in four regional ROIs (frontal, temporal, parietal and occipital lobes). The non-smoking patient group had a significantly higher intellectual quotient (IQ) compared with the patients who smoked, and our results varied according to whether IQ was included as a covariate. Without IQ correction, significant between-group effects for FA were found in four ROIs: total brain, total cortical, frontal lobe and the occipital lobe. In all cases the FA was lower among the smoking patient group, and highest in the control group. Smoking patients differed significantly from non-smoking patients in the frontal lobe ROI. However, these differences were no longer significant after IQ correction. FA differences between non-smoking patients and controls were not significant. Among smoking and non-smoking patients with schizophrenia but not healthy controls, FA was correlated with IQ. In conclusion, group effects of smoking on FA in schizophrenia might be mediated by IQ. Further, low FA in specific brain areas may be a neural marker for complex pathophysiology and risk for diverse problems such as schizophrenia, low IQ, and nicotine addiction.

Brain morphology at entry into treatment for alcohol dependence is related to relapse propensity

BACKGROUND

We examined whether any differences in brain volumes at entry into alcohol dependence treatment differentiate subsequent Abstainers from Relapsers.

METHODS

Individuals in alcohol dependence treatment (n = 75) underwent magnetic resonance imaging approximately 6 ± 4 days after their last alcoholic drink, and 40 age-matched nonsmoking light drinkers (LD) were studied as control subjects. At follow-up 7.8 ± 2.6 months later, 23 alcoholics (31%) had abstained from drinking and 52 (69%) had relapsed. Deformation morphometry compared Relapsers, Abstainers, and LD.

RESULTS

Compared with LD, future Abstainers had smaller brain tissue volumes in the left amygdala, hippocampal head, and entorhinal cortex and bilaterally in the thalamus and adjacent subcortical white matter (WM) and had larger volume in the left lateral orbitofrontal region. Compared with LD, future Relapsers had smaller brain tissue volumes in the right middle temporal, occipital, and superior frontal WM. Compared with future Abstainers, future Relapsers had smaller tissue volumes primarily in bilateral orbitofrontal cortex and surrounding WM. Results were virtually unaffected after controlling for common comorbidities.

CONCLUSIONS

At entry into alcohol dependence treatment, the brain structure of future Relapsers differs from that of future Abstainers. Future Relapsers have smaller brain volumes in regions of the mesocorticolimbic reward system that are critically involved in impulse control, emotional regulation, craving, and evaluation and anticipation of stimulus salience and hedonics. Structural abnormalities of this circuitry might confer greater risk for resumption of hazardous drinking after treatment and might contribute to the definition of a neurobiological relapse risk profile in alcohol dependence.

Brain grey matter deficits in smokers: focus on the cerebellum

Structural cerebral deficiencies in smokers have been well characterized by morphometric investigations focussing on cortical and subcortical structures. Although the role of the cerebellum is increasingly noted in mental and addiction disorders, no reports exist regarding cerebellar alterations in smokers employing a methodology specifically designed to assess the cerebellar morphology. We acquired high-resolution MRI scans from 33 heavy smokers and 22 never-smokers and used a voxel-based morphometry (VBM) approach utilizing the Spatially Unbiased Infratentorial (SUIT) toolbox (Diedrichsen 2006) to provide an optimized and fine-grained exploration of cerebellar structural alterations associated with smoking. Relative to never-smokers, smokers showed significant reductions of grey matter volume in the right cerebellum Crus I. The grey matter volume in Crus I correlated negatively with the amount of nicotine dependence as assessed by means of the Fagerström scale. Since Crus I has been identified as the cognitive division of the cerebellum, the structural deficit may in part mediate cognitive deficits previously reported in smokers. Of note, the dependence-related magnitude of the volume deficit may support the notion that the cerebellum is substantially involved in core mechanisms of drug dependence.

Vitamin E decreased the activity of acetylcholinesterase and level of lipid peroxidation in brain of rats exposed to aged and diluted sidestream smoke

INTRODUCTION

The biological systems of both smoker and passive smoking suffer changes caused by toxic compounds from cigarette smoke such as inflammation, lipid peroxidation, and deficiency of vitamin E. The aim of the present study was to evaluate the effect of vitamin E on acetylcholinesterase (AChE) activity and the lipid peroxidation level in the brain of rats in the model of exposure to aged and diluted sidestream smoke (ADSS).

METHODS

Adult male Wistar rats (200-300 g) were exposed to ADSS for 4 weeks and treated with vitamin E (50 mg/kg/day) loaded by gavage. In the first, second, third, and fourth weeks, animals were concomitantly exposed to the smoke of 1, 2, 3, and 4 cigarettes/day, respectively. The duration of each exposure was 15 min, daily.

RESULTS

For rats exposed to ADSS, the AChE activity and lipid peroxidation level increased in the striatum, cerebral cortex, and cerebellum. In contrast, the activity of AChE and the level of lipid peroxidation decreased in the smoke group treated with vitamin E.

CONCLUSIONS

The results suggest that the rats exposed to ADSS and treated with vitamin E significantly reduced the raised activity of AChE and level lipid peroxidation from the brain structures studied. The study, therefore, concludes that vitamin E could be considered as a therapeutic agent in this type of exposure.

Alcohol and the human brain: a systematic review of different neuroimaging methods

BACKGROUND

Imaging techniques have been in widespread use in the scientific community for more than 3 decades. They facilitate noninvasive, in vivo studies of the human brain in both healthy and diseased persons. These brain-imaging techniques have contributed significantly to our understanding of the effects of alcohol abuse and dependence on structural and functional changes in the human brain. A systematic review summarizing these contributions has not previously been conducted, and this is the goal of the current paper.

METHODS

The databases PubMed, PsycINFO, and PSYNDEX were searched using central key words. Fulfilling the inclusion criteria were 140 functional and structural imaging studies, together comprising data from more than 7,000 patients and controls. The structural imaging techniques we considered were cranial computerized tomography and various magnetic resonance imaging-based techniques, including voxel-based morphometry, deformation-based morphometry, diffusion tensor magnetic resonance imaging, and diffusion-weighted magnetic resonance imaging. The functional methods considered were magnetic resonance spectroscopy, positron emission tomography, single photon emission computed tomography, and functional magnetic resonance imaging.

RESULTS

Results from studies using structural imaging techniques have revealed that chronic alcohol use is accompanied by volume reductions of gray and white matter, as well as microstructural disruption of various white matter tracts. These changes are partially reversible following abstinence. Results from functional imaging methods have revealed metabolic changes in the brain, lower glucose metabolism, and disruptions of the balance of neurotransmitter systems. Additionally, functional imaging methods have revealed increased brain activity in the mesocorticolimbic system in response to alcohol-themed pictures relative to nondrug-associated stimuli, which might be of predictive value with regard to relapse.

CONCLUSIONS

There has been tremendous progress in the development of imaging technologies. Use of these technologies has clearly demonstrated the structural and functional brain abnormalities that can occur with chronic alcohol use. The study of the alcoholic brain provides an heuristic model which furthers our understanding of neurodegenerative changes in general, as well as their partial reversibility with sustained abstinence. Additionally, functional imaging is poised to become an important tool for generating predictions about individual brain functioning, which can then be used as a basis for personalized medicine.

A preliminary investigation of varenicline for heavy drinking smokers

RATIONALE

Varenicline, an approved smoking cessation pharmacotherapy, also shows promise as a potential treatment for alcohol dependence. However, varenicline has not been tested in heavy drinkers, and it remains to be determined whether varenicline could reduce alcohol craving and consumption in smokers who are trying to quit smoking.

OBJECTIVES

We conducted a preliminary study to examine the effect of varenicline on drinking behavior and the effects of extended varenicline pretreatment on smoking.

METHODS

Thirty heavy drinking smokers received smoking cessation counseling and were randomly assigned to receive either an extended 4-week pretreatment with varenicline 2 mg daily or the usual 1-week pretreatment. Those in the extended pretreatment group received active medication for 8 weeks (i.e., 4 weeks of active pre-treatment followed by 4 weeks of active treatment), and participants in the usual pretreatment group received active medication after a placebo lead in (i.e., 3 weeks of placebo followed by active medication for 5 weeks).

RESULTS

Participants who received varenicline during the first 3 weeks reported significantly greater reductions in alcohol craving and numerically fewer heavy drinking days compared to those who received placebo, and these differences persisted during the open-label phase. Extended pretreatment was associated with numerically greater reductions in cigarette smoking over the entire study period. There were no differences, however, in smoking abstinence rates following the smoking quit date between the two groups.

CONCLUSIONS

Findings from this preliminary study suggest that varenicline may be a promising strategy for concurrently reducing heavy drinking and promoting smoking changes in heavy drinkers.

Reduced thickness of medial orbitofrontal cortex in smokers

BACKGROUND

Structural deficiencies within the prefrontal cortex might be related to drug-taking behavior that prevails in smokers. Cortical thickness has been found to be a structural modulator of cerebral function and cognition and a subtle correlate of mental disorders. However, to date an analysis of cortical thickness in smokers compared with never-smokers has not been undertaken.

METHODS

We acquired high-resolution magnetic resonance imaging scans from 22 smokers and 21 never-smokers and used FreeSurfer to model the gray-white and pial surfaces for each individual cortex to compute the distance between these surfaces to obtain a measure of cortical thickness. The main cortical folds were aligned across individuals with FreeSurfer's surface-based averaging technique to compare whole brain differences in cortical thickness between smokers and never-smokers.

RESULTS

Relative to never-smokers, smokers showed greater cortical thinning in the left medial orbitofrontal cortex (mOFC). Cortical thickness measures extracted from mOFC correlated negatively with the amount of cigarettes consumed/day and the magnitude of lifetime exposure to tobacco smoke.

CONCLUSIONS

The brains of smokers are structurally different from those of never-smokers in a dose-dependent manner. The cortical thinning in mOFC in smokers relative to never-smokers might imply dysfunctions of the brain's reward, impulse control, and decision-making circuits. Related behavioral correlates are suggested to be relevant for smoking initiation and maintenance.

Quitting smoking and change in alcohol consumption in the International Tobacco Control (ITC) Four Country Survey

Although frequent heavy drinking has been associated with decreased odds of quitting smoking, the extent to which smoking cessation is associated with decreased alcohol consumption is less clear. The present study examined over a 2-year period whether individuals who quit smoking for at least 6 months, compared to those making a quit attempt but continuing to smoke and to those not making any attempt to quit smoking, showed greater reductions in drinking frequency, average weekly quantity of alcohol consumption, and frequency of heavy drinking. Data were drawn from the International Tobacco Control Four Country Survey, a prospective cohort study of smokers in Australia, Canada, the UK, and the US. A total of 3614 participants provided alcohol data at one study wave and were re-interviewed 2 years later regarding smoking and alcohol use. Consistent with prior studies, individuals who drank heavily (4+/5+ drinks for women and men, respectively) more than once a week had especially low rates of quitting smoking. There was little evidence, however, that those who achieved sustained smoking cessation made greater reductions in drinking compared to those who continued to smoke. These results were consistent across countries and sexes and did not differ significantly by heaviness of smoking. Results indicate that quitting smoking, in and of itself, does not lead to meaningful changes in alcohol use. Therefore, interventions and policies directed towards increasing smoking cessation are unlikely to affect rates of hazardous drinking unless they include specific elements that address alcohol consumption.

Transcallosal white matter degradation detected with quantitative fiber tracking in alcoholic men and women: selective relations to dissociable functions

INTRODUCTION

Excessive alcohol consumption can adversely affect white matter fibers and disrupt transmission of neuronal signals. Here, we examined six anatomically defined transcallosal white matter fiber bundles and asked whether any bundle was specifically vulnerable to alcohol, what aspect of white matter integrity was most affected, whether women were more vulnerable than men, and whether evidence of compromise in specific bundles was associated with deficits in balance, sustained attention, associative learning, and psychomotor function, commonly affected in alcoholics.

METHODS

Diffusion tensor imaging quantitative fiber tracking assessed integrity of six transcallosal white matter bundles in 87 alcoholics (59 men, 28 women) and 88 healthy controls (42 men, 46 women). Measures included orientational diffusion coherence (fractional anisotropy, FA) and magnitude of diffusion, quantified separately for axial (longitudinal; lambdaL) and radial (transverse; lambdaT) diffusivity. The Digit Symbol Test and a test of ataxia were also administered.

RESULTS

Alcoholism negatively affected callosal FA and lambdaT of all but the sensory-motor bundle. Women showed no evidence for greater vulnerability to alcohol than men. Multiple regression analyses confirmed a double dissociation: higher diffusivity in sensory-motor and parietal bundles was associated with poorer balance but not psychomotor speed, whereas higher diffusivity in prefrontal and temporal bundles was associated with slower psychomotor speed but not balance.

CONCLUSIONS

This study revealed stronger alcohol effects for FA and radial diffusivity than axial diffusivity, suggesting myelin degradation, but no evidence for greater vulnerability to alcohol in women than men. The presence of brain-behavior relationships provides support for the role of alcoholism-related commissural white matter degradation as a substrate of cognitive and motor impairment. Identification of a double dissociation provides further support for the role of selective white matter integrity in specific domains of performance.

The effect of alcohol and nicotine abuse on gene expression in the brain

Alcohol intake at levels posing an acute heath risk is common amongst teenagers. Alcohol abuse is the second most common mental disorder worldwide. The incidence of smoking is decreasing in the Western world but increasing in developing countries and is the leading cause of preventable death worldwide. Considering the longstanding history of alcohol and tobacco consumption in human societies, it might be surprising that the molecular mechanisms underlying alcohol and smoking dependence are still incompletely understood. Effective treatments against the risk of relapse are lacking. Drugs of abuse exert their effect manipulating the dopaminergic mesocorticolimbic system. In this brain region, alcohol has many potential targets including membranes and several ion channels, while other drugs, for example nicotine, act via specific receptors or binding proteins. Repeated consumption of drugs of abuse mediates adaptive changes within this region, resulting in addiction. The high incidence of alcohol and nicotine co-abuse complicates analysis of the molecular basis of the disease. Gene expression profiling is a useful approach to explore novel drug targets in the brain. Several groups have utilised this technology to reveal drug-sensitive pathways in the mesocorticolimbic system of animal models and in human subjects. These studies are the focus of the present review.

Addressing tobacco use disorder in smokers in early remission from alcohol dependence: the case for integrating smoking cessation services in substance use disorder treatment programs

Despite the declining overall rate of cigarette smoking in the general population in the United States, the prevalence of smoking is estimated to be as high as 80% among treatment-seeking alcoholics. The serious adverse health effects of tobacco and heavy alcohol use are synergistic and recent evidence suggests that smoking slows the process of cognitive recovery following alcohol abstinence. In addition, substantial evidence shows that treatment for tobacco dependence does not jeopardize alcohol abstinence. In this paper, we focus on the impact and treatment implications of tobacco dependence among treatment-seeking alcoholics through a review of five areas of research. We begin with brief reviews of two areas of research: studies investigating the genetic and neurobiological vulnerability of comorbid tobacco and alcohol dependence and studies investigating the consequences of comorbid dependence on neurobiological and cognitive functioning. We then review literature on the effects of smoking cessation on drinking urges and alcohol use and the effectiveness of smoking cessation interventions with alcoholic smokers. Finally, we offer recommendations for research with an emphasis on clinical research for enhancing smoking cessation outcomes in this population.

Smoking, nicotine and neuropsychiatric disorders

Tobacco smoking is an extremely addictive and harmful form of nicotine (NIC) consumption, but unfortunately also the most prevalent. Although disproportionately high frequencies of smoking and its health consequences among psychiatric patients are widely known, the neurobiological background of this epidemiological association is still obscure. The diverse neuroactive effects of NIC and some other major tobacco smoke constituents in the central nervous system may underlie this association. This present paper summarizes the pharmacology of NIC and its receptors (nAChR) based on a systematic review of the literature. The role of the brain's reward system(s) in NIC addiction and the results of functional and structural neuroimaging studies on smoking-related states and behaviors (i.e. dependence, craving, withdrawal) are also discussed. In addition, the epidemiological, neurobiological, and genetic aspects of smoking in several specific neuropsychiatric disorders are reviewed and the clinical relevance of smoking in these disease states addressed.

Degradation of association and projection white matter systems in alcoholism detected with quantitative fiber tracking

BACKGROUND

Excessive alcohol use can cause macrostructural tissue shrinkage with regional preference for frontal systems. The extent and locus of alcoholism's effect on white matter microstructure is less known.

METHODS

Quantitative fiber tracking derived from diffusion tensor imaging (DTI) assessed the integrity of samples of 11 major white matter bundles in 87 alcoholics (59 men, 28 women) and 88 healthy control subjects (42 men, 46 women). Fiber integrity was expressed as fractional anisotropy (FA) and apparent diffusion coefficient (ADC), quantified separately for longitudinal diffusivity (lambdaL), a putative index of axonal integrity, and transverse diffusivity (lambdaT), a putative index of myelin integrity.

RESULTS

Alcoholism affected FA and diffusivity, particularly lambdaT, of several fiber bundles. Frontal and superior sites (frontal forceps, internal and external capsules, fornix, and superior cingulate and longitudinal fasciculi) showed greatest abnormalities in alcoholics relative to control subjects. More posterior and inferior bundles were relatively spared. Lifetime alcohol consumption correlated with regional DTI measures in alcoholic men but not women. When matched for alcohol exposure, alcoholic women showed more DTI signs of white matter degradation than alcoholic men in several fiber bundles. Among all alcoholics, poorer performance on speeded tests correlated with DTI signs of regional white matter degradation.

CONCLUSIONS

This survey of multiple brain fiber systems revealed a differential pattern of alcoholism's effect on regional FA and diffusivity with functional consequences attributable in part to compromised fiber microstructure with prominence in signs of myelin degradation. Sex-based differences suggest that women are at enhanced risk for alcoholism-related degradation in selective white matter systems.

Addressing heavy drinking in smoking cessation treatment: a randomized clinical trial

Heavy alcohol use frequently co-occurs with cigarette smoking and may impede smoking cessation. This clinical trial examined whether smoking cessation treatment that incorporates brief alcohol intervention can improve smoking cessation outcomes (7-day verified point prevalence abstinence) and reduce drinks consumed per week. Heavy drinkers seeking smoking cessation treatment were assigned by urn randomization to receive, along with 8 weeks of nicotine replacement therapy, either a 4-session standard smoking cessation treatment (ST, n = 119) or standard treatment of equal intensity that incorporated brief alcohol intervention (ST-BI, n = 117). Across follow-ups over 26 weeks, participants in ST-BI reported approximately 20% fewer drinks per week (p < .027) and greater smoking abstinence (adjusted odds ratio = 1.56; 95% confidence interval = 1.01, 2.43) than did those in ST; however, effects on smoking were primarily evident at 2 weeks after quit date and were essentially absent by 16 weeks. The effect of ST-BI on smoking outcome was most robust among moderately heavy drinkers compared with that on very heavy drinkers. Integrating brief alcohol intervention into smoking cessation treatment appears feasible, but further development is needed to yield lasting effects on smoking.

Magnetic resonance imaging studies of cigarette smoking

This chapter reviews studies that have applied magnetic resonance imaging (MRI) toward a better understanding of the neurobiological correlates and consequences of cigarette smoking and nicotine dependence. The findings demonstrate that smokers differ from nonsmokers in regional brain structure and neurochemistry, as well as in activation in response to smoking-related stimuli and during the execution of cognitive tasks. We also review functional neuroimaging studies on the effects of nicotine administration on brain activity, both at rest and during the execution of cognitive tasks, independent of issues related to nicotine withdrawal and craving. Although chronic cigarette smoking is associated with poor cognitive performance, acute nicotine administration appears to enhance cognitive performance and increase neural efficiency in smokers.

Diffusion abnormalities in adolescents and young adults with a history of heavy cannabis use

BACKGROUND

There is growing evidence that adolescence is a key period for neuronal maturation. Despite the high prevalence of marijuana use among adolescents and young adults in the United States and internationally, very little is known about its impact on the developing brain. Based on neuroimaging literature on normal brain developmental during adolescence, we hypothesized that individuals with heavy cannabis use (HCU) would have brain structure abnormalities in similar brain regions that undergo development during late adolescence, particularly the fronto-temporal connection.

METHOD

Fourteen young adult males in residential treatment for cannabis dependence and 14 age-matched healthy male control subjects were recruited. Patients had a history of HCU throughout adolescence; 5 had concurrent alcohol abuse. Subjects underwent structural and diffusion tensor magnetic resonance imaging. White matter integrity was compared between subject groups using voxelwise and fiber tractography analysis.

RESULTS

Voxelwise and tractography analyses revealed that adolescents with HCU had reduced fractional anisotropy, increased radial diffusivity, and increased trace in the homologous areas known to be involved in ongoing development during late adolescence, particularly in the fronto-temporal connection via arcuate fasciculus.

CONCLUSIONS

Our results support the hypothesis that heavy cannabis use during adolescence may affect the trajectory of normal brain maturation. Due to concurrent alcohol consumption in five HCU subjects, conclusions from this study should be considered preliminary, as the DTI findings reported here may be reflective of the combination of alcohol and marijuana use. Further research in larger samples, longitudinal in nature, and controlling for alcohol consumption is needed to better understand the pathophysiology of the effect of cannabis on the developing brain.