Should criteria for drug dependence differ across drugs?

Electronic harm reduction interventions for drug overdose monitoring and prevention: A scoping review

BACKGROUND

Novel strategies are required to address rising overdose deaths across the globe. We sought to identify the breadth and depth of the existing evidence around electronic harm reduction (e-harm reduction) interventions that aimed to reduce the harms associated with substance use.

METHODS

We conducted a scoping review according to the PRISMA-ScR and PRISMA for Searching guidelines. A health sciences librarian systematically searched seven health databases from inception until January 20, 2023. Citation chaining and reference lists of included studies were searched to identify additional articles. Two reviewers independently screened, extracted and charted the data. Additionally, we conducted a gray literature search and environmental scan to supplement the findings.

RESULTS

A total of 51 studies met the criteria for inclusion (30 peer-reviewed articles and 21 non-peer reviewed). Most peer-reviewed studies were conducted in Western countries (USA = 23, Canada = 3, Europe = 3, China = 1) and among adult samples (adult = 27, youth/adults =1, unspecified = 2). Study designs were predominantly quantitative (n = 24), with a minority using qualitative (n = 4) or mixed methods (n = 2). Most e-harm reduction interventions were harm reduction (n = 15), followed by education (n = 6), treatment (n = 2), and combined/other approaches (n = 7). Interventions utilized web-based/mobile applications (n = 15), telephone/telehealth (n = 10), and other technology (n = 5).

CONCLUSIONS

While e-harm reduction technology is promising, further research is required to establish the efficacy and effectiveness of these novel interventions.

Validity of the DSM-5 tobacco use disorder diagnostics in adults with problematic substance use

BACKGROUND

DSM-5 tobacco use disorder (TUD) nosology differs from DSM-IV nicotine dependence (ND) by including craving and DSM-IV abuse criteria, a lower threshold (≥ 2 criteria), and severity levels (mild; moderate; severe). We assessed concurrent and prospective validity of the DSM-5 TUD diagnosis and severity and compared validity with DSM-IV ND diagnosis.

METHODS

The sample included U.S. adults with current problematic substance use and past year cigarette smoking (N = 396). Baseline assessment collected information on DSM-IV ND and DSM-5 TUD criteria, smoking-related variables, and psychopathology. Over the following 90 days, electronic daily assessments queried smoking and cigarette craving. Variables expected to be related to TUD were validators: cigarette consumption, cigarette craving scale, Fagerström Test for Nicotine Dependence, and psychiatric disorders. Regression models estimated the association of each validator with DSM-5 TUD and severity levels, and differential association between DSM-5 TUD and DSM-IV ND diagnoses.

RESULTS

DSM-5 TUD and DSM-IV ND were associated with most baseline validators (p-values < 0.05), with significantly stronger associations with DSM-5 TUD for number of days smoked (p = 0.023) and cigarette craving scale (p = 0.007). Baseline DSM-5 TUD and DSM-IV ND predicted smoking and craving on any given day during follow-up, with stronger associations for DSM-5 TUD (association difference [95% CI%]: any smoking, 0.53 [0.27, 0.77]; number of cigarettes smoked, 1.36 [0.89, 1.78]; craving scale, 0.19 [0.09, 0.28]). Validators were associated with TUD severity in a dose-dependent manner.

CONCLUSION

DSM-5 TUD diagnostic measures as operationalized here demonstrated concurrent and prospective validity. Inclusion of new criteria, particularly craving, improved validity and clinical relevance.

Item Response Theory analyses of DSM-5 substance use disorder criteria in French outpatient addiction clinic participants. How much is craving special?

BACKGROUND

To evaluate the dimensionality and psychometric validity of the 11 DSM-5 criteria for 5 substance use disorders, with a focus on craving, and taking into account age, gender and psychiatric comorbidities in a French sample of subjects seeking addiction treatment.

METHODS

This cross-sectional study, included participants with DSM-5 substance use disorders that sought treatment for at least one addiction from outpatient clinics. Diagnostic criteria were evaluated with the Mini international Neuropsychiatric Interview. In Current regular user (2 times per week), factor and 2-parameter IRT analysis was used to investigate the dimensionality and psychometric properties of the 11 DSM-5 SUD criteria. Differential Item and Test functioning (DIF and DTF) analysis were performed across sociodemographic characteristics and psychiatric disorders.

RESULTS

1359 participants (alcohol n = 787, opiates n = 131, cocaine n = 141, tobacco n = 1014, cannabis n = 504), were included (68% male; mean age 38.7). One-factor dimensionality was confirmed, except for tobacco. Craving criterion had the strongest factor loadings, lower difficulty (range, -1.29 to -0.67) and higher discrimination (range, 2.11-3.05), and no DIF compared to other criteria. The tobacco criteria set functioned differently by mood and anxiety disorders.

CONCLUSIONS

We confirmed the unidimensionality of the 11 SUD DSM-5 criteria and furthermore that craving was the most selective criterion because of its psychometric properties and no DIF compared to other criteria, regardless of the substance in this adult clinical sample. Unidimensionality of tobacco criteria was not confirmed, suggesting DSM-IV abuse criteria limitations as indicators of the construct.

An Item Response Theory Analysis of DSM-5 Heroin Use Disorder in a Clinical Sample of Chinese Adolescents

The study examined the dimensionality and psychometric properties of Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria for heroin use disorder in a clinical sample of Chinese adolescents using item response theory approach. We examined 168 adolescents aged 14.8–17.9 years, who were in treatment for heroin use disorder. A two-parameter logistic item response theory model was conducted to examine the severity and discrimination of DSM-5 criteria for heroin use disorder. Differential item functioning across age and ethnicity was assessed. Results supported the hypothesis that the DSM-5 criteria for heroin use disorder were arrayed an underlying unitary dimension of severity in clinical adolescents. All the items exhibited good discriminatory power in distinguishing between clinical adolescent heroin users. Although three criteria exhibited measurement non-invariance at the item level, the overall DSM-5 heroin use disorder diagnostic criteria set appears to achieve measurement invariance at the scale level.

An explanatory model for the concept of mental health in Iranian youth

Background: Mental health is considered as an integral and essential component of overall health. Its determinants and related factors are one of the most important research priorities, especially in adolescents and young people. Using a qualitative approach, the present study aimed to identify factors affecting the mental health of youth in Iran.

Methods: In 2017, following content analysis principles, and using semi-structured in-depth interviews, we conducted a qualitative study exploring the opinions of young people about mental health. A targeted sampling method was used, and participants were young volunteers aged 18 to 30 who were selected from Tehran province, Iran. Inclusion criteria for participants was willingness to participate in the study, and ability to express their experiences. Data collection was done with individual in-depth interviews. According to the explanatory model, the interviews were directed toward the concept of mental health and path of causality and auxiliary behaviors.

Results: 21 young adults participated, who met the study inclusion criteria, of whom 12 participants were male. Their mean age was 24.4 ± 0.41 years and their education varied from primary school to Master’s degree. Mental health was considered as mental well-being and a sense of satisfaction and efficacy, not only the presence of a disease or mental disorder. Based on the opinions of the interviewees, three factors of personal characteristics, family and society are involved in mental health. Individual factors were associated with behavioral and physical problems. One of the most important issues was revealed as tensions in societal and family conflicts. Economic problems and unemployment of young people were also extracted from the social factor.

Conclusion: In Iran, social factors such as jobs for the unemployed and job security are considered as important determinants in the mental health of young people.

Anhedonia and the relative reward value of drug and nondrug reinforcers in cigarette smokers

Anhedonia-a psychopathologic trait indicative of diminished interest, pleasure, and enjoyment-has been linked to use of and addiction to several substances, including tobacco. We hypothesized that anhedonic drug users develop an imbalance in the relative reward value of drug versus nondrug reinforcers, which could maintain drug use behavior. To test this hypothesis, we examined whether anhedonia predicted the tendency to choose an immediate drug reward (i.e., smoking) over a less immediate nondrug reward (i.e., money) in a laboratory study of non-treatment-seeking adult cigarette smokers. Participants (N = 275, ≥10 cigarettes/day) attended a baseline visit that involved anhedonia assessment followed by 2 counterbalanced experimental visits: (a) after 16-hr smoking abstinence and (b) nonabstinent. At both experimental visits, participants completed self-report measures of mood state followed by a behavioral smoking task, which measured 2 aspects of the relative reward value of smoking versus money: (1) latency to initiate smoking when delaying smoking was monetarily rewarded and (2) willingness to purchase individual cigarettes. Results indicated that higher anhedonia predicted quicker smoking initiation and more cigarettes purchased. These relations were partially mediated by low positive and high negative mood states assessed immediately prior to the smoking task. Abstinence amplified the extent to which anhedonia predicted cigarette consumption among those who responded to the abstinence manipulation, but not the entire sample. Anhedonia may bias motivation toward smoking over alternative reinforcers, perhaps by giving rise to poor acute mood states. An imbalance in the reward value assigned to drug versus nondrug reinforcers may link anhedonia-related psychopathology to drug use.

Evaluating the Validity of Caffeine Use Disorder

Caffeine use disorder is included in the conditions for further study section of the DSM-5. Caffeine's profile of neurobiological, behavioral, and clinical effects is similar to other common substances that humans use recreationally. Extant data suggest that a clinically meaningful addictive disorder develops in some regular caffeine users, but this literature is incomplete and not yet sufficient to determine if and how best to define and treat caffeine use disorder. An overview of the literature relevant to determining the clinical importance of problematic caffeine use is followed by discussion of potential concerns and benefits associated with its classification as a mental disorder. Concerns about overdiagnosis and trivialization of other psychiatric syndromes are weighed against the public health benefits of increased awareness and development of interventions targeting problematic caffeine use. This discussion includes consideration of alternative diagnostic approaches, improvement of assessment practices, and the need for additional clinical and epidemiological research.

Commonalities and Differences Across Substance Use Disorders: Phenomenological and Epidemiological Aspects

BACKGROUND

Although psychoactive substances vary in many ways, they have important commonalties, particularly in their ability to lead to an addiction syndrome. The field lacks an updated review of the commonalities and differences in the phenomenology of alcohol, cannabis, tobacco, stimulants, opioids, hallucinogens, sedatives/tranquilizers, and inhalants and their related substance use disorders (SUDs).

METHODS

DSM-IV and DSM-5 SUD diagnostic criteria were reviewed, as was evidence from recent epidemiological and clinical research: psychometric studies (test-retest reliability, latent trait analysis); physiological indicators (tolerance, withdrawal); prevalence and age of onset. Information was incorporated from previous reviews, PubMed and Scopus literature searches, and data from large U.S. national surveys.

RESULTS

Empirical evidence in the form of test-retest reliability and unidimensionality supports use of the same DSM-IV dependence or DSM-5 SUD diagnostic criteria across substances. For most substances, the criteria sets were generally most informative in general population samples at moderate-to-severe levels of SUD. Across substances, 2 criteria (tolerance and use in hazardous situations) were identified as functioning differently in population subgroups. Since substances have different pharmacological effects, withdrawal is assessed using substance-specific symptoms, while tolerance is not; issues remain with the assessment of tolerance. Alcohol, tobacco, and cannabis were consistently identified as the substances with earliest onset of use, highest prevalence of lifetime use, and highest prevalence of lifetime disorder.

CONCLUSIONS

Despite differences between psychoactive substances, the generic DSM criteria set appears equally applicable across substances. Additional studies of tolerance and hazardous use will be useful for future nosologies. Alcohol, cannabis, and tobacco are the substances with the greatest public health impact due to the high prevalence and early onset of their use, and the potential all 3 substances have to lead to addiction.

Kinetic modelling for the assay of nortriptyline hydrochloride using potassium permanganate as oxidant

Kinetic methods for accurate determination of nortriptyline hydrochloride have been described. The methods are based on the oxidation of nortriptyline hydrochloride with KMnO4 in acidic and basic media. In acidic medium, the decrease in absorbance at 525.5 nm and in basic medium, the increase in absorbance at 608.5 nm were measured as a function of time. The variables affecting the reactions were carefully investigated and optimised. Kinetic models such as initial rate, rate constant, variable time and fixed time were employed to construct the calibration curves. The initial rate and fixed time methods were selected for quantification of nortriptyline hydrochloride. In acidic medium, the calibration curves showed a linear response over the concentration range 10-50 μg mL(-1) for initial rate and 10-60 μg mL(-1) for fixed time method (2 min). In basic medium, the calibration graphs were linear over the concentration range 10-100 μg mL(-1) for initial rate and fixed time methods (4 min). In acidic medium, the limits of detection for initial rate and fixed time methods (2 min) were 1.02 and 3.26 μg mL(-1), respectively. In basic medium, the limits of detection were found to be 1.67 and 1.55 μg mL(-1) for initial rate and fixed time methods (4 min), respectively. The initial rate and fixed time methods have been successfully applied to the determination of nortriptyline hydrochloride in commercial dosage form. Statistical comparison of the results of the proposed methods with those of reference method exhibited excellent agreement and there is no significant difference between the compared methods in terms of accuracy and precision.

Factor structure of early smoking experiences and associations with smoking behavior: valence or sensitivity model?

The Early Smoking Experience (ESE) questionnaire is the most widely used questionnaire to assess initial subjective experiences of cigarette smoking. However, its factor structure is not clearly defined and can be perceived from two main standpoints: valence, or positive and negative experiences, and sensitivity to nicotine. This article explores the ESE's factor structure and determines which standpoint was more relevant. It compares two groups of young Swiss men (German- and French-speaking). We examined baseline data on 3,368 tobacco users from a representative sample in the ongoing Cohort Study on Substance Use Risk Factors (C-SURF). ESE, continued tobacco use, weekly smoking and nicotine dependence were assessed. Exploratory structural equation modeling (ESEM) and structural equation modeling (SEM) were performed. ESEM clearly distinguished positive experiences from negative experiences, but negative experiences were divided in experiences related to dizziness and experiences related to irritations. SEM underlined the reinforcing effects of positive experiences, but also of experiences related to dizziness on nicotine dependence and weekly smoking. The best ESE structure for predictive accuracy of experiences on smoking behavior was a compromise between the valence and sensitivity standpoints, which showed clinical relevance.

Validity of proposed DSM-5 diagnostic criteria for nicotine use disorder: results from 734 Israeli lifetime smokers

BACKGROUND

The fifth edition of the diagnostic and statistical manual of mental disorders (DSM-5) proposes aligning nicotine use disorder (NUD) criteria with those for other substances, by including the current DSM fourth edition (DSM-IV) nicotine dependence (ND) criteria, three abuse criteria (neglect roles, hazardous use, interpersonal problems) and craving. Although NUD criteria indicate one latent trait, evidence is lacking on: (1) validity of each criterion ; (2) validity of the criteria as a set ; (3) comparative validity between DSM-5 NUD and DSM-IV ND criterion sets ; and (4) NUD prevalence.

METHOD

Nicotine criteria (DSM-IV ND, abuse and craving) and external validators (e.g., smoking soon after awakening, number of cigarettes per day) were assessed with a structured interview in 734 lifetime smokers from an Israeli household sample. Regression analysis evaluated the association between validators and each criterion. Receiver operating characteristic analysis assessed the association of the validators with the DSM-5 NUD set (number of criteria endorsed) and tested whether DSM-5 or DSM-IV provided the most discriminating criterion set. Changes in prevalence were examined.

RESULTS

Each DSM-5 NUD criterion was significantly associated with the validators, with strength of associations similar across the criteria. As a set, DSM-5 criteria were significantly associated with the validators, were significantly more discriminating than DSM-IV ND criteria, and led to increased prevalence of binary NUD (two or more criteria) over ND.

CONCLUSIONS

All findings address previous concerns about the DSM-IV nicotine diagnosis and its criteria and support the proposed changes for DSM-5 NUD, which should result in improved diagnosis of nicotine disorders.

The reinforcement threshold for nicotine as a target for tobacco control

BACKGROUND

Cigarette smoking represents an enormous public health problem worldwide that leads to over 5 million deaths per year. The gradual reduction of the nicotine content of cigarettes below the threshold that is required to develop addiction is one strategy that might substantially reduce the number of addicted smokers and prevent adolescents from becoming addicted to nicotine (Benowitz and Henningfield, 1994). While the potential public health benefits of this approach are enormous, the guiding concepts and relevant empirical evidence needed to support the implementation of a nicotine reduction policy require a critical examination.

METHODS

The purpose of this paper is to briefly review the current concepts and research regarding nicotine reduction while also discussing the utility of the addictive threshold for nicotine in this approach. The accurate determination of the nicotine addiction threshold presents some conceptual challenges as there is a lack of consensus on how to best measure nicotine addiction. This difficulty can impede the progress for developing a science-based tobacco control policy. As an alternative, the nicotine reinforcement threshold is a relatively clear concept, and well-accepted methods and criteria are available to measure nicotine reinforcement.

RESULTS

However, there are many gaps in our current knowledge concerning the nicotine reinforcement threshold in humans. The threshold for nicotine reinforcement remains to be determined in controlled settings using different populations of current or potential tobacco users. In addition, the value of the nicotine reinforcement threshold in predicting tobacco use in real-world settings needs to be examined. The results of such studies will determine the potential utility of the estimated threshold for nicotine reinforcement in developing science-based tobacco control policies.

Nicotine don't get no respect: a replication test

INTRODUCTION

Although nicotine/tobacco use is the most prevalent, most deadly, and most treatable drug problem, a 1994 study by the author found that few scientific articles that generally discussed "drug/substance abuse/dependence/use" included nicotine as a focus. This analysis tested if this finding is still true in journals published in 2010-2011.

METHOD

A random sample (n = 100) of articles whose titles used the term "drug/substance abuse/dependence/use" or "addiction" and did not refer to specific drugs in the 2010-2011 issues of the 5 leading drug abuse/addiction journals.

RESULTS

One fourth (25%) of these articles included nicotine/tobacco dependence/use or smoking as a focus, whereas 82% included alcohol or an illicit drug as a focus (p < .001). Only 3 articles (4%) mentioned the exclusion of tobacco/nicotine dependence/use.

CONCLUSIONS

These results suggest most researchers consider nicotine/tobacco dependence/use to be different from other types of drug dependence. Whether nicotine is included when the term "drug/substance dependence/abuse/use" is used in a scientific article varies and could lead to confusion about the prevalence, harms, costs, treatment methods, etc. associated with drug use. The author recommends the use of the adjective "non-nicotine" when appropriate to avoid confusion.

Relationship of substance abuse to dependence in the U.S. general population

OBJECTIVE

The diagnostic categories of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, for substance abuse and dependence are commonly used in clinical work and research studies, but whether abuse and dependence represent two different syndromes has been debated. The purpose of this article is to investigate the relationship of substance abuse and dependence for cannabis, cocaine, stimulants and sedatives among lifetime users of these substances in the National Epidemiologic Survey on Alcohol and Related Conditions, a nationally representative survey conducted in 2001-2002.

METHOD

The multiple indicators multiple causes (MIMIC) model addresses three sets of relationships: those between (1) diagnostic criteria and latent factors, (2) latent factors and covariates, and (3) criteria and covariates. This approach allows for the detection of and compensation for noninvariance of the measurement of criteria across subgroups.

RESULTS

Compared with one-factor models, two-factor models (factors roughly corresponding to abuse and dependence) fit significantly better across all substances, with abuse and dependence factors highly correlated. The MIMIC model indicated that race/ethnicity, age, income, and marital status showed some differential relationships across substance groups, although most covariates showed similar associations to dependence and abuse factors. Noninvariance of criteria measurement by demographic covariates was most pronounced for cannabis abuse and dependence criteria.

CONCLUSIONS

The general relationship of abuse to dependence was consistent across substances. Results were equivocal on the value of retaining separate factors; therefore, investigating the relationships of specific genetic variants and treatment outcomes to dimensional indicators of abuse, dependence, and measures combining these criteria is warranted. Measurement of cannabis abuse and dependence criteria appears most affected by demographic characteristics.

The genetics of addiction-a translational perspective

Addictions are serious and common psychiatric disorders, and are among the leading contributors to preventable death. This selective review outlines and highlights the need for a multi-method translational approach to genetic studies of these important conditions, including both licit (alcohol, nicotine) and illicit (cannabis, cocaine, opiates) drug addictions and the behavioral addiction of disordered gambling. First, we review existing knowledge from twin studies that indicates both the substantial heritability of substance-specific addictions and the genetic overlap across addiction to different substances. Next, we discuss the limited number of candidate genes which have shown consistent replication, and the implications of emerging genomewide association findings for the genetic architecture of addictions. Finally, we review the utility of extensions to existing methods such as novel phenotyping, including the use of endophenotypes, biomarkers and neuroimaging outcomes; emerging methods for identifying alternative sources of genetic variation and accompanying statistical methodologies to interpret them; the role of gene-environment interplay; and importantly, the potential role of genetic variation in suggesting new alternatives for treatment of addictions.

Greater prevalence of proposed DSM-5 nicotine use disorder compared to DSM-IV nicotine dependence in treated adolescents and young adults

AIMS

Compared to DSM-IV nicotine dependence, proposed DSM-5 nicotine use disorder (NUD) would lower the threshold from three to two symptoms, and increase the number of criteria used for diagnosis from seven to 11. The impact of the proposed changes on nicotine disorder prevalence and the concurrent validity of diagnostic criteria were examined.

DESIGN

Cross-sectional survey to compare DSM-IV and proposed DSM-5 algorithms.

SETTING AND PARTICIPANTS

Adolescent (n = 179) and young adult (n = 292) past-year cigarette users recruited from addictions treatment.

MEASUREMENTS

Semi-structured clinical interview to evaluate DSM-IV nicotine dependence, and 10 of the 11 proposed DSM-5 NUD criteria; 30-day time-line follow-back; and the Fagerström Test for Nicotine Dependence (FTND).

FINDINGS

Prevalence of proposed DSM-5 NUD (two-symptom threshold) was much higher (adolescents: 68.7%, young adults: 86.0%) than DSM-IV nicotine dependence (33.0% and 59.6%, respectively), although prevalence of DSM-5 severe NUD (four-symptom threshold) was similar to DSM-IV nicotine dependence. Concurrent validity analyses in both samples indicated consistent support for DSM-5 severe NUD diagnosis (four symptoms) but not for the moderate NUD (two symptoms) diagnosis, which had modest relations with only FTND score. IRT analyses indicated strong support for the new craving item, but not for the proposed interpersonal problems and hazardous use items.

CONCLUSIONS

The proposed DSM-5 nicotine use disorder criteria have substantial limitations when applied to adolescents and young adults, and appear to have low concurrent validity.

Primary outcome indices in illicit drug dependence treatment research: systematic approach to selection and measurement of drug use end-points in clinical trials

AIMS

Clinical trials test the safety and efficacy of behavioral and pharmacological interventions in drug-dependent individuals. However, there is no consensus about the most appropriate outcome(s) to consider in determining treatment efficacy or on the most appropriate methods for assessing selected outcome(s). We summarize the discussion and recommendations of treatment and research experts, convened by the US National Institute on Drug Abuse, to select appropriate primary outcomes for drug dependence treatment clinical trials, and in particular the feasibility of selecting a common outcome to be included in all or most trials.

METHODS

A brief history of outcomes employed in prior drug dependence treatment research, incorporating perspectives from tobacco and alcohol research, is included. The relative merits and limitations of focusing on drug-taking behavior, as measured by self-report and qualitative or quantitative biological markers, are evaluated.

RESULTS

Drug-taking behavior, measured ideally by a combination of self-report and biological indicators, is seen as the most appropriate proximal primary outcome in drug dependence treatment clinical trials.

CONCLUSIONS

We conclude that the most appropriate outcome will vary as a function of salient variables inherent in the clinical trial, such as the type of intervention, its target, treatment goals (e.g. abstinence or reduction of use) and the perspective being taken (e.g. researcher, clinical program, patient, society). It is recommended that a decision process, based on such trial variables, be developed to guide the selection of primary and secondary outcomes as well as the methods to assess them.

DSM criteria for tobacco use disorder and tobacco withdrawal: a critique and proposed revisions for DSM-5

AIMS

This paper aims to identify appropriate criteria for tobacco dependence assessment, evaluate relevant research and suggest revisions that may be incorporated into DSM-5.

METHODS

Desirable conceptual and psychometric features of tobacco dependence assessments were identified, including the types of outcomes against which such assessment should be validated. DSM-IV criteria were matched against these criteria and compared with other dependence measures.

RESULTS

DSM-IV criteria were found to be ambiguous, little used in tobacco research, and have relatively low predictive validity. Other dependence measures were found to have greater validity in the prediction of important dependence features such as relapse likelihood. Strength of urges to smoke on typical smoking days and during abstinence, markers of nicotine intake or frequency of smoking and latency to smoke soon after waking were found to be useful dependence measures.

CONCLUSION

The use and utility of DSM-5 will be enhanced by eliminating most DSM-IV criteria and adding new ones based on smoking pattern, smoking heaviness, and the severity of craving during periods of smoking and withdrawal.

The DSM Guided Cannabis Screen (DSM-G-CS): description, reliability, factor structure and empirical scoring with a clinical sample

Clinicians need cannabis-specific diagnostic screens compatible with DSM-IV-TR and proposed DSM-5. A clinical sample (n=174) completed the DSM-Guided-Cannabis Screen (DSM-G-CS) 21 and 11 criteria versions and three drug comparison measures. DSM-G-CS descriptive statistics, reliabilities, three factor analyses, and eight ROC and discriminant analyses evaluated construct validity and empirical scoring. DSM-G-CS reliabilities are .88 (21-items) and .85 (11-criteria). Factor analyses (FA) with varimax rotation derived six and three factors explaining 62% to 60% of variances for the DSM-G-CS 21 and 11 respectively, with ≥.400 loadings supporting retention of all items. Cannabis withdrawal subscale reliability .952 (10-items) and FA supported one factor composite item. ROC and discriminant analyses supports DSM-G-CS 1.5 to 2.5 scoring cutoffs as empirically sound, based upon sensitivity-specificity maximums, accuracy probabilities, confidence levels and correctly classified percentages, optimal with Marijuana Screening Inventory (MSI) comparisons. Results support DSM-G-CS construct validity, empirical scoring and compatibility with DSM-IV-TR cannabis abuse or dependence and proposed DSM-5 cannabis use disorder diagnostic models. Clinically, DSM-G-CS scores of two to three (or more) suggest probable cannabis-use disorder, deserving assessment to determine diagnostic accuracy.

A latent class analysis of DSM-IV and Fagerström (FTND) criteria for nicotine dependence

BACKGROUND

Nicotine dependence is associated with considerable morbidity and mortality. Two predominant classification systems, the Diagnostic and Statistical Manual (DSM-IV) and Fagerström Test for Nicotine Dependence (FTND), have been used to measure liability to nicotine dependence, yet few studies have attempted to simultaneously examine both sets of criteria.

METHODS

Using a sample of 624 regular smoking individuals who are offspring of Vietnam Era Twin fathers ascertained for an offspring of twin study, we applied latent class analysis to the 7 DSM-IV and the 6 FTND criteria to classify individuals by their nicotine dependence symptom profiles. Post-hoc across-class comparisons were conducted using a variety of smoking-related variables and aspects of psychopathology. Whether a single class identified offspring at high genetic and environmental vulnerability was also investigated.

RESULTS

The cross-diagnosis kappa was .30. A 4-class solution fit these data best. The classes included a low DSM-low FTND class and a high DSM-high FTND class; a moderate DSM-moderate FTND class, which was distinguished by moderate levels of smoking and intermediate levels of comorbid psychopathology; and a light smoking-moderate FTND class consisting primarily of lighter smokers with a more recent onset of regular smoking. High genetic and environmental vulnerability to nicotine dependence was noted in all classes with no statistically significant across-class differences.

CONCLUSIONS

In general, the DSM-IV and FTND criteria performed similarly to define a continuum of risk for nicotine dependence. The emerging class of light smokers should be further investigated to assess whether they transition to another class or remain as such.

Food dependence in rats selectively bred for low versus high saccharin intake. Implications for "food addiction"

The "food addiction" concept implies that proneness to drug dependence and to food dependence should covary. The latter was studied in low- (LoS) and high- (HiS) saccharin-consuming rats, who differ in drug self-administration (HiS>LoS) and withdrawal (LoS>HiS). Sugary food intake in the first 1-2 h was higher in HiS than LoS rats. Sugar intake predicted startle during abstinence only among LoS rats. These results may suggest bingeing-proneness in HiS rats and withdrawal-proneness among LoS rats. However, intake escalation and somatic withdrawal did not differ between lines. Further study with selectively bred rats, with attention to definitions and measures, is warranted.

A systematic review of the Diagnostic and Statistical Manual diagnostic criteria for nicotine dependence

The Diagnostic and Statistical Manual diagnostic criteria for nicotine dependence (DSM-ND) are based on the proposition that dependence is a syndrome that can be diagnosed only when a minimum of 3 of the 7 proscribed features are present. The DSM-ND criteria are an accepted research measure, but the validity of these criteria has not been subjected to a systematic evaluation. To systematically review evidence of validity and reliability for the DSM-ND criteria, a literature search was conducted of 16 national and international databases. Each article with original data was independently reviewed by two or more reviewers. In total, 380 potentially relevant articles were examined and 169 were reviewed in depth. The DSM-ND criteria have seen wide use in research settings, but sensitivity and specificity are well below the accepted standards for clinical applications. Predictive validity is generally poor. The 7 DSM-ND criteria are regarded as having face validity, but no data support a 3-symptom ND diagnostic threshold, or a 4-symptom withdrawal syndrome threshold. The DSM incorrectly states that daily smoking is a prerequisite for withdrawal symptoms. The DSM shows poor to modest concurrence with all other measures of nicotine dependence, smoking behaviors and biological measures of tobacco use. The data support the DSM-ND criteria as a valid measure of nicotine dependence severity for research applications. However, the data do not support the central premise of a 3-symptom diagnostic threshold, and no data establish that the DSM-ND criteria provide an accurate diagnosis of nicotine dependence.

Delineating the psychic structure of substance abuse and addictions: should anxiety, mood and impulse-control dysregulation be included?

Current "official" nosology (e.g. DSM IV) is largely limited to physical manifestations of addiction that can be objectively observed and are suited to the maintaining of an "atheoretical" perspective. However, addicted subjects display additional psychiatric symptoms that affect their well-being and social functioning and, in accordance with DSM IV, are typically relegated to the domain of psychiatric "comorbidity." We contend that the relationship of these psychiatric symptoms with addiction is very close, as demonstrated by the high frequency of association observed. We further assert that substance use may modify pre-existing psychic structures such as temperament and related subthreshold conditions and lead to addiction as a specific mental disorder, inclusive also of symptoms pertaining to mood/anxiety, or impulse-control dimensions. The present contribution addresses the weaknesses of the current DSM-based nosology of addiction-related mental comorbidity. We highlight the overlap of the biological substrates and the neurophysiology of addictive processes and psychiatric symptoms associated with addiction, and propose the inclusion of specific mood, anxiety, and impulse-control dimensions in the psychopathology of addictive processes. We postulate that addiction reaches beyond the mere result of drug-elicited effects on the brain and cannot be peremptorily equated only with the use of drugs despite the adverse consequences produced. We infer that mood, anxiety and impulse-control dysregulation is at the very core of both the origins and clinical manifestations of addiction and should be incorporated into the nosology of the same, emphasising how addiction is a relapsing chronic condition in which psychiatric manifestations play a crucial role. To conclude, addictionology cannot be severed from its psychopathological connotations, in view of the undeniable presence of symptoms, of their manifest contribution to the way addicted patients feel and behave, and to the role they play in maintaining the continued use of substances.

Exploring the role of a nicotine quantity-frequency use criterion in the classification of nicotine dependence and the stability of a nicotine dependence continuum over time

INTRODUCTION

This study investigated (a) the utility of a cigarette quantity-frequency (QF) use criterion as an indicator for nicotine dependence (ND) and (b) the stability of the ND continuum of severity over time.

METHOD

Data from individuals who smoked cigarettes in the year prior to both time points of the National Epidemiologic Survey on Alcohol and Related Conditions were analyzed (n = 6,185). The Alcohol Use Disorder and Associated Disabilities Interview Schedule DSM-IV Version (AUDADIS-IV) assessed for DSM-IV ND and nicotine use. Three QF criteria were created to represent daily consumption of > or = 5 cigarettes, > or = 10 cigarettes, or > or = 20 cigarettes. Confirmatory factor analysis and item response theory analysis were used to explore the latent structure of ND. Differential item functioning (DIF) analysis investigated the stability of the ND continuum over time.

RESULTS

A one-factor model, representing the DSM-IV conceptualization of ND, was an acceptable fit to the data at both time points. The inclusion of QF criteria decreased the fit of the one-factor model of ND. DIF in the severity and discrimination parameters of the diagnostic criteria was evident across the time points of the survey.

DISCUSSION

Although QF of cigarette use is related to ND, it appears to be a separate construct. Researchers using the AUDADIS-IV should be aware that the characteristics of the DSM-IV ND criteria do vary slightly across time, even though the changes appear to be relatively small and of minor clinical or practical significance.

Abuse liability assessment of tobacco products including potential reduced exposure products

The harm produced by tobacco products is a result of frequent use of a highly toxic product. Reducing the adverse public health impact of tobacco products might be most effectively achieved by reducing the likelihood of their use and the toxicity of the products. Products that retain some characteristics of cigarettes but have been altered with the intention of reducing toxicity have been referred to as modified risk tobacco products or potential reduced exposure products (MRTP/PREP). Evaluation of their content, emission, and toxicity is discussed in other articles in this special issue. Here, we discuss the methodology that has been used to examine the likelihood of abuse or addiction. Abuse liability assessment (ALA) methodology has been used by the Food and Drug Administration (FDA) and other drug regulatory agencies world-wide for decades to assess the risks posed by a wide variety of pharmacologically active substances. ALA is routinely required among other evaluations of safety during the pre-market assessment of new drugs, and is continually adapted to meet the challenges posed by new drug classes and drug formulations. In the 2009 law giving FDA regulation over tobacco products, FDA is now required to evaluate new tobacco products including MRTP/PREPs to determine their risk for abuse and toxicity at the population level. This article describes the traditional tools and methods of ALA that can be used to evaluate new tobacco and nicotine products including MRTP/PREPs. Such ALA data could contribute to the scientific foundation on which future public policy decisions are based.

Are differences in guidelines for the treatment of nicotine dependence and non-nicotine dependence justified?

Despite the many similarities between nicotine dependence and other drug dependences, national guidelines for their treatment differ in several respects. The recent national guideline for the treatment of nicotine dependence has (i) less emphasis on detailed assessment; (ii) less emphasis on treatment of psychiatric comorbidity; (iii) less acceptance of reduction of use as an initial treatment goal; (iv) greater emphasis on pharmacological interventions; and (v) less emphasis on psychosocial treatment than national guidelines for non-nicotine dependences. These treatment differences may occur because (i) nicotine does not cause behavioral intoxication; (ii) psychiatric comorbidity is less problematic with nicotine dependence; (iii) psychosocial problems are less severe with nicotine dependence; and (iv) available pharmacotherapies for nicotine dependence are safer, more numerous and more easily available. However, it is unclear whether these treatment differences are, in fact, justifiable because of the scarcity of empirical tests. We suggest several possible empirical tests.

Smokers' beliefs about the inability to stop smoking

We recruited 367 current daily smokers via the Internet and randomized them to rate the causes of an inability to stop smoking, inability to stop problem alcohol use, or inability to lose excess weight in a fictional scenarios. Most smokers attributed inability to stop smoking to addiction (88%), habit (88%) and stress (62%). Surprisingly, equal numbers of smokers agreed and disagreed that inability to stop smoking was due to lack of willpower or motivation. Most disagreed that it was due to biological factors, denial, family/upbringing, genetics, mental disease, personality problem, psychological problems, or weakness of character. Many expected correlations among perceived causes were not found; e.g. endorsement of addiction was not inversely related to endorsement of willpower. Most smokers endorsed treatment. Higher ratings of addiction were related to endorsing treatment, and higher ratings of motivation were related to endorsing no need for treatment; however, these relationships were of small magnitude. Ratings of almost all the causes varied across the three problems; e.g. ratings of addiction were greater for smoking than for problem alcohol use. In summary, smokers appear to view the inability to stop smoking as multicausal; however, their views of causes are only weakly related to attitudes towards treatment. Given the several unexpected findings, qualitative research into smokers' conceptualizations about smokers' inability to stop smoking is indicated.

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.

The construct and measurement equivalence of cocaine and opioid dependences: a National Drug Abuse Treatment Clinical Trials Network (CTN) study

INTRODUCTION

Although DSM-IV criteria are widely used in making diagnoses of substance use disorders, gaps exist regarding diagnosis classification, use of dependence criteria, and effects of measurement bias on diagnosis assessment. We examined the construct and measurement equivalence of diagnostic criteria for cocaine and opioid dependences, including whether each criterion maps onto the dependence construct, how well each criterion performs, how much information each contributes to a diagnosis, and whether symptom-endorsing is equivalent between demographic groups.

METHODS

Item response theory (IRT) and multiple indicators-multiple causes (MIMIC) modeling were performed on a sample of stimulant-using methadone maintenance patients enrolled in a multisite study of the National Drug Abuse Treatment Clinical Trials Network (CTN) (N=383). Participants were recruited from six community-based methadone maintenance treatment programs associated with the CTN and major U.S. providers. Cocaine and opioid dependences were assessed by DSM-IV Checklist.

RESULTS

IRT modeling showed that symptoms of cocaine and opioid dependences, respectively, were arrayed along a continuum of severity. All symptoms had moderate to high discrimination in distinguishing drug users between severity levels. "Withdrawal" identified the most severe symptom of the cocaine dependence continuum. MIMIC modeling revealed some support for measurement equivalence.

CONCLUSIONS

Study results suggest that self-reported symptoms of cocaine and opioid dependences and their underlying constructs can be measured appropriately among treatment-seeking polysubstance users.

An item response theory modeling of alcohol and marijuana dependences: a National Drug Abuse Treatment Clinical Trials Network study

OBJECTIVE

The aim of this study was to examine psychometric properties of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), diagnostics criteria for alcohol and marijuana dependences among 462 alcohol users and 311 marijuana users enrolled in two multisite trials of the National Drug Abuse Treatment Clinical Trials Network.

METHOD

Diagnostic questions were assessed by the DSM-IV checklist. Data were analyzed by the item response theory and the multiple indicators-multiple causes method procedures.

RESULTS

Criterion symptoms of alcohol and marijuana dependences exhibited a high level of internal consistency. All individual symptoms showed good discrimination in distinguishing alcohol or marijuana users between high and low severity levels of the continuum. In both groups, "withdrawal" appeared to measure the most severe symptom of the dependence continuum. There was little evidence of measurement nonequivalence in assessing symptoms of dependence by gender, age, race/ethnicity, and educational level.

CONCLUSIONS

These findings highlight the clinical utility of the DSM-IV checklist in assessing alcohol- and marijuana dependence syndromes among treatment-seeking substance users.

Test of the role of nicotine dependence in the relation between posttraumatic stress disorder and panic spectrum problems

Posttraumatic stress disorder (PTSD) frequently co-occurs with panic spectrum problems. Relatively little empirical work has tested possible mechanisms accounting for this association. Nicotine dependence often ensues subsequent to PTSD onset and research suggests smoking high numbers of cigarettes daily may lead to panic problems. The current study tested the hypotheses that nicotine dependence partially mediates the relations between PTSD and both panic attacks and panic disorder within a nationally representative sample of 5,692 (3,020 women; M(Age) = 45, SD = 18) adults from the National Comorbidity Survey-Replication. Results were consistent with hypotheses. These findings support the theory suggesting smoking among people with PTSD may be involved in the development of panic problems.

Randomized controlled trial of a brief intervention for problematic prescription drug use in non-treatment-seeking patients

AIMS

Dependence on or problematic use of prescription drugs (PD) is estimated to be between 1 and 2% in the general population. In contrast, the proportion of substance-specific treatment in PD use disorders at 0.5% is comparatively low. With an estimated prevalence of 4.7%, PD-specific disorders are widespread in general hospitals compared to the general population. Brief intervention delivered in general hospitals might be useful to promote discontinuation or reduction of problematic prescription drug use.

DESIGN

A randomized, controlled clinical trial.

SETTING

Internal, surgical and gynaecological wards of a general and a university hospital.

PARTICIPANTS

One hundred and twenty-six patients fulfilling criteria for either regular use of PD (more than 60 days within the last 3 months) or dependence on or abuse of PD, respectively, were allocated randomly to two conditions.

INTERVENTION

Subjects received two counselling sessions based on Motivational Interviewing plus an individualized written feedback (intervention group, IG) or a booklet on health behaviour (control group, CG).

MEASUREMENTS

The outcome was measured as reduction (>25%) and discontinuation of PD intake in terms of defined daily dosages (DDD).

FINDINGS

After 3 months, more participants in the IG reduced their DDD compared to the participants in the CG (51.8% versus 30%; chi(2) = 6.17; P = 0.017). In the IG 17.9%, in the CG 8.6% discontinued use of PD (chi(2) = 2.42; P = 0.17). Conclusions Brief intervention based on Motivational Interviewing is effective in reducing PD intake in non-treatment-seeking patients.

How should we revise diagnostic criteria for substance use disorders in the DSM-V?

This article reviews literature on the validity and performance characteristics of the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) diagnostic criteria for substance use disorders (SUDs) and recommends changes in these criteria that should be considered for the next edition of the DSM (DSM-V). Substantial data indicate that DSM-IV substance abuse and substance dependence are not distinct categories and that SUD criteria are best modeled as reflecting a unidimensional continuum of substance-problem severity. The conceptually and empirically problematic substance abuse diagnosis should be abandoned in the DSM-V, with substance dependence defined by a single set of criteria. Data also indicate that various individual SUD criteria should be revised, dropped, or considered for inclusion in the DSM-V. The DSM-V should provide a framework that allows the integration of categorical and dimensional approaches to diagnosis. Important areas for further research are noted.

Individual differences in nicotine dependence, withdrawal symptoms, and sex predict transient fMRI-BOLD responses to smoking cues

Exposure to smoking cues increases craving for cigarettes and can precipitate relapse. Whereas brain imaging studies have identified a distinct network of brain regions subserving the processing of smoking cues, little is known about the influence of individual difference factors and withdrawal symptoms on brain cue reactivity. Multiple regression analysis was used to evaluate relations between individual difference factors and withdrawal symptoms and event-related blood oxygen level-dependent responses to visual smoking cues in a sample of 30 smokers. Predictors were self-report nicotine dependence (Fagerström test of nicotine dependence, FTND), prescan withdrawal symptoms (craving and negative affect), and sex. The unique variance of each predictor was examined after controlling for each of the others. Positive associations were observed between FTND and reactivity to cues in right anterior cingulate and orbitofrontal cortex (OFC) whereas negative associations were observed between prescan craving and reactivity in ventral striatum. Higher negative affect or being male was associated with greater reactivity in left hippocampus and left OFC. Women exhibited greater cue reactivity than men in regions including the cuneus and left superior temporal gyrus. Individual difference factors and withdrawal symptoms were uniquely associated with brain reactivity to smoking cues in regions subserving reward, affect, attention, motivation, and memory. These findings provide further evidence that reactivity to conditioned drug cues is multiply determined and suggest that smoking cessation treatments designed to reduce cue reactivity focus on each of these variables.

Older versus younger treatment-seeking smokers: differences in smoking behavior, drug and alcohol use, and psychosocial and physical functioning

Quitting smoking benefits older individuals, yet few recent studies have described older smokers. The goal of this paper was to test a series of hypotheses about differences between smokers aged 50 years or older (50+) and those younger than age 50 (<50) presenting to the same treatment facility during 2002-2004 for participation in two randomized clinical trials: one exclusively for smokers aged 50+, and a second open to smokers aged 18 or older. As predicted, smokers aged 50+ were more tobacco dependent, had better psychological functioning, and had poorer physical functioning than those aged <50. Contrary to predictions, we found no differences in motivation to quit cigarette smoking or in alcohol use. Women aged 50+ were less likely to report marijuana use than women aged <50, and less likely than men to receive a positive diagnosis for alcohol abuse. Despite higher scores on measures of tobacco dependence, older smokers were less likely to be diagnosed as tobacco dependent or as having tobacco withdrawal using DSM-IV criteria. Rates of DSM-IV alcohol abuse and dependence were high in both age groups but were higher for smokers aged <50. We found no striking differences between studies in reasons for exclusion, but in both the proportion of individuals excluded due to current antidepressant use was high. Implications for the assessment and treatment of older adults are discussed.

Evaluating the validities of different DSM-IV-based conceptual constructs of tobacco dependence

AIM

To compare the concurrent and predictive validities of two subsets of DSM-IV criteria for nicotine dependence (tolerance and withdrawal; withdrawal; difficulty controlling use; and use despite harm) to the concurrent and predictive validity of the full DSM-IV criteria.

DESIGN

Analysis of baseline and outcome data from three randomized clinical trials of cigarette smoking treatment.

SETTING

San Francisco, California.

PARTICIPANTS

Two samples of cigarette smokers (n = 810 and 322), differing with regard to baseline characteristics and treatment received, derived from three randomized clinical trials.

MEASUREMENTS

DSM-IV nicotine dependence criteria were measured at baseline with a computerized version of the Diagnostic Interview Schedule for DSM-IV (DIS-IV). Additional baseline measures included the Fagerström Test of Nicotine Dependence (FTND), number of cigarettes smoked per day, breath carbon monoxide (CO) level, the Minnesota Nicotine Withdrawal Scale (MNWS), the Michigan Nicotine Reinforcement Questionnaire (M-NRQ) and the Profile of Mood States (POMS). Seven-day point-prevalence abstinence was assessed at week 12.

FINDINGS

Full DSM-IV criteria displayed greater concurrent validity than either of the two subsets of criteria. However, DSM-IV symptoms accounted for only a nominal amount of the variance in baseline smoking-related characteristics and were unrelated to smoking abstinence at week 12. Cigarettes smoked per day was the only significant predictor of abstinence at week 12.

CONCLUSIONS

Although the findings do not provide a compelling alternative to the full set of DSM-IV nicotine dependence criteria, its poor psychometric properties and low predictive power limit its clinical and research utility.

Psychometric properties of DSM assessments of illicit drug abuse and dependence: results from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC)

BACKGROUND

DSM-IV criteria for illicit drug abuse and dependence are largely based on criteria developed for alcohol use disorders and there is a lack of research evidence on the psychometric properties of these symptoms when applied to illicit drugs.

METHOD

This study utilizes data on abuse/dependence criteria for cannabis, cocaine, stimulants, sedatives, tranquilizers, opiates, hallucinogens and inhalants from the National Epidemiological Survey on Alcohol and Related Conditions (NESARC, n=43 093). Analyses included factor analysis to explore the dimensionality of illicit drug abuse and dependence criteria, calculation of item difficulty and discrimination within an item response framework and a descriptive analysis of 'diagnostic orphans': individuals meeting criteria for 1-2 dependence symptoms but not abuse. Rates of psychiatric disorders were compared across groups.

RESULTS

Results favor a uni-dimensional construct for abuse/dependence on each of the eight drug classes. Factor loadings, item difficulty and discrimination were remarkably consistent across drug categories. For each drug category, between 29% and 51% of all individuals meeting criteria for at least one symptom did not receive a formal diagnosis of either abuse or dependence and were therefore classified as 'orphans'. Mean rates of disorder in these individuals suggested that illicit drug use disorders may be more adequately described along a spectrum of severity.

CONCLUSIONS

While there were remarkable similarities across categories of illicit drugs, consideration of item difficulty suggested that some alterations to DSM regarding the relevant severity of specific abuse and dependence criteria may be warranted.

Reevaluating the nicotine delivery kinetics hypothesis

RATIONALE

The view of smoking as an addiction to nicotine implies that nicotine is an addictive drug and a primary reinforcer. However, nicotine other than in tobacco does not appear to be very rewarding for smokers. This potential anomaly to the nicotine addiction thesis is resolved by the proposition that the reward associated with smoking depends on "high-nicotine boli." According to the nicotine delivery kinetics hypothesis, smoked nicotine reaches the brain in 5-10 s in high concentrations, which provide reinforcing "hits" of nicotine to the brain.

OBJECTIVES

Because of its essential role in the nicotine addiction thesis, this review set out to examine the current empirical basis of the nicotine delivery kinetics hypothesis.

MATERIALS AND METHODS

We reviewed studies that bear on two questions: First, does nicotine from cigarettes reach the brain significantly faster than from other nicotine delivery devices? Second, is there a relationship between delivery kinetics and any rewarding effects of nicotine?

RESULTS

There is little empirical support for the nicotine delivery kinetics hypothesis. Several studies found that arterial nicotine levels associated with smoking are much lower than predicted by the nicotine delivery kinetics thesis and not higher than with other nicotine delivery devices. More importantly, comparisons of nicotine delivery devices with varying speeds of delivery do not suggest any correlation between nicotine delivery profile and subjective reward.

CONCLUSIONS

This review indicates that the wide endorsement of the nicotine delivery kinetics hypothesis is unjustified. Critical research is required to resolve the anomalies within the nicotine addiction theory of smoking.

Euphoriant effects of nicotine in smokers: fact or artifact?

RATIONALE

The claim that nicotine in cigarettes is euphoriant to smokers is largely based on two studies (Pomerleau and Pomerleau, Psychopharmacology, 108:460-465, 1992; Tobacco Control, 3:374, 1994) in which smokers were instructed to respond to sensations of rush, buzz, or high while smoking low-nicotine or regular cigarettes. However, the assumption that these sensations are pleasurable was not tested and may have biased the results.

OBJECTIVES

The aim of this study was to re-examine the claim that smoked nicotine is euphoriant to smokers.

METHODS

Study 1 surveyed the frequency and pleasantness of the smoking-related sensations of rush, buzz, and high in a sample of smokers. Study 2 replicated Pomerleau and Pomerleau (Psychopharmacology, 108:460-465, 1992) with two sets of instruction. One set, as in the original study, defined these sensations as pleasurable, whereas the other defined them as unpleasant.

RESULTS

Study 1 found that whereas rush and high were perceived as pleasant, buzz was unpleasant to most smokers. Study 2 found that under both sets of instructions, smokers reported more sensations when smoking the regular, as compared to the low-nicotine cigarette. Additionally, the sensations of rush, buzz, and high were rated as more pleasant under the pleasant instructions as compared to the unpleasant instructions. Finally, in the pleasant instructions condition, many participants reported having pressed the button to indicate a pleasurable sensation despite having actually experienced that sensation as unpleasant.

CONCLUSIONS

Our results suggest that the findings of Pomerleau and Pomerleau (Psychopharmacology, 108:460-465, 1992; Tobacco Control, 3:374, 1994) may have been biased by the experimental instructions and cannot be taken as evidence that smoked nicotine is euphoriant to smokers.

Characteristics of nosologically informative data sets that address key diagnostic issues facing the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-V) and International Classification of Diseases, eleventh edition (ICD-11) substance use disorders workgroups

AIMS

Over the past two decades, many nosological issues have been addressed by the Diagnostic and Statistical Manual of Mental Disorders (DSM) and International Classification of Diseases (ICD) substance use disorders workgroups. Even with those efforts, there are key issues that have not been resolved and must be revisited, or addressed de novo, by the workgroups. These lingering points are broad, due to the array of substances classified under the diagnostic umbrella of substance use disorders. They include substantive issues ranging from dimensional approaches, similar criteria for each substance, cut-points and thresholds, distinct abuse and dependence classifications, new criteria and drugs, to less substantive ones, such as the adjectives used to describe the severity of the behaviors.

RESULTS

This paper describes the characteristics of the data sets that will be needed to resolve the key nosological issues. Ten points are described: (1) data must be true to nomenclature under study; (2) flexible regarding rearrangements of scoring algorithms; (3-4) able to assess substances individually and retain former versions of the criteria; (5) not rely on shortened versions; (6) utilize samples that are generalizable; (7) make diagnoses with transparent algorithms; (8) combine mixed methods for corroborating data; (9) utilize assessments that collect reliable and valid diagnoses and criteria; and (10) stretch the limits by allowing for new discoveries.

CONCLUSIONS

This paper describes each of these and gives examples of the limitations and strengths of data for the purpose of defining a useful, unified concept of addictive behaviors.

Are specific dependence criteria necessary for different substances: how can research on cannabis inform this issue?

AIMS

Research on cannabis dependence is used to comment on the similarities and differences among the substance dependence disorders, and to address the issue of whether specific versus generic substance dependence diagnostic criteria might offer the most fruitful approach to diagnosis. If cannabis dependence can be diagnosed and characterized adequately using the extant generic Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) dependence criteria, then one could argue that these diagnostic guidelines are valid and of high utility for substances with more well-accepted dependence syndromes.

METHODS

A brief, selective critical review of research on cannabis withdrawal and on the validity and internal consistency of cannabis dependence as assessed via DSM criteria for cannabis dependence was performed.

RESULTS

Findings from these reports indicate that cannabis dependence is much more similar to than different from other types of substance dependence, even with regard to withdrawal. The generic DSM-IV dependence criteria can be applied fairly well to cannabis, and yield findings similar to that observed with other substance dependence disorders. However, across substances, the generic criteria may not discriminate cases in a manner consistent with the underlying constructs of abuse and dependence, and cross-substance differences probably exist in the general dependence severity level and specific symptom profiles.

CONCLUSIONS

The use of generic DSM-IV criteria appears to work as well for cannabis dependence as for other substances, yet the more important question might be as to whether we can do better by developing more sophisticated generic criteria or by using substance specific criteria.