Truth or consequences in the diagnosis of substance use disorders

The cultural aspect: How to measure and interpret epidemiological data on alcohol-use disorders across cultures

AIMS

To examine the cultural impact on the diagnosis of alcohol-use disorders using European countries as examples.

DESIGN

Narrative review.

RESULTS

There are strong cultural norms guiding heavy drinking occasions and loss of control. These norms not only indicate what drinking behaviour is acceptable, but also whether certain behaviours can be reported or not. As modern diagnostic systems are based on lists of mostly behavioural criteria, where alcohol-use disorders are defined by a positive answer on at least one, two or three of these criteria, culture will inevitably co-determine how many people will get a diagnosis. This explains the multifold differences in incidence and prevalence of alcohol-use disorders, even between countries where the average drinking levels are similar. Thus, the incidence and prevalence of alcohol-use disorders as assessed by surveys or rigorous application of standardised instruments must be judged as measuring social norms as well as the intended mental disorder.

CONCLUSIONS

Current practice to measure alcohol-use disorders based on a list of culture-specific diagnostic criteria results in incomparability in the incidence, prevalence or disease burden between countries. For epidemiological purposes, a more grounded definition of diagnostic criteria seems necessary, which could probably be given by using heavy drinking over time.

Exploration of Core Symptoms for the Diagnosis of Alcohol Dependence in the ICD-10

BACKGROUND

The classification of alcohol use disorder has changed over the past century. Now, the conceptualization of alcohol dependence is still controversial. Accumulating evidence has shown the reliability and validity for the diagnosis of alcohol dependence in the ICD-10 and DSM-IV. However, the meaning and association of the respective diagnostic items, which are descriptive of representative symptoms, have hardly been examined. The core symptom of substance use disorder has been debated in various situations, but has never been elucidated logically.

METHODS

We consecutively registered 192 patients with alcohol-related problems who visited our hospital for the first time during a certain period. The relations and principal components among the checked items of the ICD-10 diagnostic criteria were examined statistically.

RESULTS

Three diagnostic items in the ICD-10 were strongly correlated with each other and were thought to form the core symptoms of alcohol dependence: "strong desire," "difficulties in controlling," and "neglect of pleasures." One major physical phenomenon, "withdrawal," seemed to complement the core symptoms in the diagnosis of alcohol dependence. Another physical phenomenon, "tolerance," was demonstrated to be a relatively independent item. The principal component analysis also demonstrated that the diagnostic item "difficulties in controlling" had the maximum component loading value, followed by 2 items, "neglect of pleasures" and "strong desire."

CONCLUSIONS

The core symptomatic elements in the diagnosis of alcohol dependence were statistically suggested in this study. Knowledge of the relations and components among the diagnostic items of alcohol dependence might also be applicable to other forms of substance use dependence and behavioral addiction.

Assessment of Withdrawal and Hangover is Confounded in the Alcohol Use Disorder and Associated Disabilities Interview Schedule: Withdrawal Prevalence is Likely Inflated

BACKGROUND

The Alcohol Use Disorder and Associated Disabilities Interview Schedule-IV (AUDADIS-IV) and AUDADIS-5 are diagnostic interviews used in major epidemiological and other studies of alcohol use disorder (AUD). Much of what we know regarding the prevalence of AUD in the United States is based upon this interview. However, past research and meta-analytic evidence suggest that differential operationalization of the AUD criteria across instruments can lead to differential endorsement of symptoms and resulting AUD diagnosis rates. In particular, studies employing the AUDADIS are observed to have markedly higher endorsement rates of withdrawal than other large epidemiological studies. One explanation for this is that when assessing withdrawal, the AUDADIS combines effects from the morning after drinking with those from the days following, thereby conflating hangover and withdrawal.

METHODS

This study addresses whether this operationalization confounds rates of endorsement when compared to simpler, less ambiguous hangover or withdrawal stems. To this aim, 497 college student drinkers were randomized into 1 of 3 stem conditions: (i) hangover (n = 164), (ii) withdrawal (n = 167), or (iii) combined AUDADIS-IV (n = 166).

RESULTS

Across conditions, participants were more likely to report the occurrence of each withdrawal symptom in the combined stem condition than in the explicit withdrawal stem condition, but not in the explicit hangover stem condition. Within the combined stem condition, probed symptoms were more likely to be reported as a result of a hangover.

CONCLUSIONS

The AUDADIS potentially results in false positives for withdrawal, arguably a pathognomonic symptom of alcoholism and, in turn, likely affects rates of the diagnosis of AUD.

How should prevalence of alcohol use disorders be assessed globally?

Alcohol is a major risk factor for global burden of disease, and alcohol use disorders make up a considerable portion of this burden. Up to now, prevalence of alcohol use disorders has been estimated based on general population surveys with the Composite International Diagnostic Interview (CIDI) as the gold standard for assessment. However, three major problems have been identified with the current conceptualization of alcohol use disorders and its measurement via CIDI: cultural specificity of key criteria measured such as loss of control; lack of convergence of diagnoses identified by CIDI with clinically relevant diagnoses in primary health care; and impact of stigma on measurement. As a solution, it is proposed to measure alcohol use disorders via heavy drinking over time, with thresholds taken from the European Medicines Agency (60 and more grams on average per day of pure alcohol for men, and 40+ grams for women). Current data on level of drinking (per capita consumption) assessed via taxation and other means allow for a measure of less bias. If these thresholds are considered too low and there is more emphasis on need for specialized treatment, then thresholds for very heavy drinking can be taken as alternatively (100+, and 60+ grams per day pure alcohol for men and women, respectively). Copyright © 2016 John Wiley & Sons, Ltd.

Meta-analysis of DSM alcohol use disorder criteria severities: structural consistency is only 'skin deep'

BACKGROUND

Item response theory (IRT) analyses of alcohol use disorder (AUD) and other psychological disorders are a predominant method for assessing overall and individual criterion severity for psychiatric diagnosis. However, no investigation has established the consistency of the relative criteria severities across different samples.

METHOD

PubMed/Medline, PsycINFO, Web of Science and ProQuest databases were queried for entries relating to alcohol use and IRT. Study data were extracted using a standardized data entry sheet. Consistency of reported criteria severities across studies was analysed using generalizability theory to estimate generalized intraclass correlations (ICCs).

RESULTS

A total of 451 citations were screened and 34 papers (30 unique samples) included in the research synthesis. The AUD criteria set exhibited low consistency in the ordering of criteria using both traditional [ICC = 0.16, 95% confidence interval (CI) 0.06-0.56] and generalized (ICC = 0.18, 95% CI 0.15-0.21) approaches. These results were partially accounted for by previously studied factors such as age and type of sample (e.g. clinical v. community), but the largest source of unreliability was the diagnostic instrument employed.

CONCLUSIONS

Despite the robust finding of unidimensional structure of AUDs, inconsistency in the relative severities across studies suggests low replicability, challenging the generalizability of findings from any given study. Explicit modeling of well-studied factors like age and sample type is essential and increases the generalizability of findings. Moreover, while the development of structured diagnostic interviews is considered a landmark contribution toward improving psychiatric research, variability across instruments has not been fully appreciated and is substantial.

Determining optimal diagnostic criteria through chronicity and comorbidity

Purpose

Contemporary approaches to clinical diagnosis have not adequately exploited state-of-the-art empirical techniques in deriving diagnostic criterion sets that are statistically optimal based on 1) relevant external indicators and 2) replicability across data sets. We provide a proof of concept that optimal criterion sets can be derived with respect to alcohol use disorder (AUD) diagnosis that are both more efficient and precise than current systems.

Methods

Using data from the National Epidemiologic Survey on Alcohol and Related Conditions we selected chronicity (i.e. persistence) of AUD diagnosis and comorbidity of AUD with other disorders as validation criteria on which to optimize the size of the AUD criterion set and the threshold for AUD diagnosis. We used cross-validation and consensus approaches for choosing a final solution.

Results

Cross-validation did not produce a solution that replicated across random subsamples or differed from conventional diagnosis. Alternatively, consensus produced a more global solution that was associated with greater validity than “conventional” diagnosis.

Conclusion

Such methods, if applied to extant diagnostic criteria and algorithms can generate simpler and more reliable rules and hold promise for greatly reducing misclassification of individuals in both research and applied clinical contexts.

Identification of smokers, drinkers and risky drinkers by general practitioners

BACKGROUND

Identification of risky substance users by general practitioners (GPs) is important for providing brief interventions or to refer cases to specialized care, but detection rates of risky users are low, with alcohol users being identified less frequently than smokers.

METHODS

We compared GPs' assessment and patient self-report concerning tobacco use, number of cigarettes smoked daily, alcohol use, alcohol use disorder, and different risky use definitions of 8476 primary care patients from six European countries. Further, we carried out a logistic regression predicting the GPs perception of the patients' alcohol problems.

RESULTS

GPs identified 88.4% (95% confidence interval (CI): 87.1-89.6%; κ=0.84, 95% CI: 0.83-0.86) of all self-reported smokers but only 64.6% (95% CI: 63.2-65.9%; κ=0.35, 95% CI: 0.33-0.37) of all current drinkers, while they were unable to judge the drinking status of every ninth patient. The GPs' estimation of number of cigarettes smoked daily was slightly lower than the self-report (Δ=0.23 cigarettes/day, p<.001) but both measures were correlated with each other. Of all risky drinkers, defined as having alcohol-related problems or showing risky drinking patterns, 28.7% (95% CI: 25.9-31.4%; κ=0.34, 95% CI: 0.31-0.37) were perceived as having problems with alcohol by the GPs. Patients' self-reported health and social consequences, as well as drinking patterns predicted the GPs' perception of alcohol problems.

CONCLUSIONS

GPs were more accurate in identifying smokers than drinkers. Concerning risky drinkers, GPs failed to diagnose a sizeable proportion but were able to detect other drinkers whom common recognition approaches had not recognized.

The harmful dysfunction model of alcohol use disorder: revised criteria to improve the validity of diagnosis and prevalence estimates

AIMS

To formulate harmful dysfunction (HD) diagnostic criteria for alcohol use disorder (AUD) and test whether they increase validity relative to standard DSM criteria, as evidenced by lowered prevalence, increased validator levels including service use, severity and family history and enhanced specificity.

DESIGN

DSM-IV AUD, DSM-IV dependence, DSM-5 AUD and HD AUD definitions were compared on eight validity related tests using nationally representative community data.

SETTING

United States.

PARTICIPANTS

National Epidemiologic Survey of Alcoholism and Related Conditions (NESARC) respondents, aged 18-54 years (wave 1, n = 29 673; wave 2, n = 24 244).

MEASURES

NESARC DSM-IV and DSM-5 criteria were taken from published studies. Whereas DSM-5 diagnosis requires any two AUD symptoms, HD criteria were constructed from NESARC items to require symptoms of both impaired-control dysfunction [withdrawal, drink to prevent/stop withdrawal, cannot stop/reduce drinking, or craving (wave 2 only)] and harm (sacrificed important activities, problems caring for home/family, job/school problems, health problems, psychological problems or problems with family/friends). Validators included service use, severity and family history, among others. Specificity was tested using a teen transient drinker criterion group.

FINDINGS

Compared with DSM-5 AUD (DSM-IV results were similar), HD criteria yielded lower prevalence (95% confidence intervals): HD life-time 6.7% (6.2, 7.2%), 1-year 2.3% (2.0, 2.5%); and DSM-5 life-time 38.2% (36.5, 39.9%), 1-year 12.4% (11.7, 13.1%). HD AUD was higher than DSM-5 on pathology validators, including: life-time alcohol-related service use: HD 41.0% (38.1, 43.9%), DSM-5 11.5% (10.7, 12.3%); severity (number of life-time alcohol symptoms): HD 20.8 (20.4, 21.2), DSM-5 10.6 (10.4, 10.8); and family history of alcohol problems: HD 50.1% (47.3, 52.9), DSM-5 32.8% (31.6, 34.0). HD criteria eliminated 83% of a DSM-5 teen transient drinker false-positives criterion group.

CONCLUSIONS

Prevalence estimates of alcohol use disorder are lowered and diagnostic validity improved when using 'harmful dysfunction' diagnostic criteria compared with standard DSM criteria, partly by reducing misdiagnosis of teenage transient drinkers.

Gendered Pathways: Violent Childhood Maltreatment, Sex Exchange, and Drug Use

OBJECTIVE

Recent work has emphasized the role of violent victimization, along with risky contexts like sex exchange, in pathways to problems of externalizing and substance use in women. Nonetheless, few studies have empirically tested gender differences involving the roles of adversity factors (e.g., childhood violent maltreatment, sex exchange) in drug use patterns. The present study tested a model of gender differences in relationships between childhood physical and sexual abuse, sex exchange, and two indicators of drug use: engagement and symptoms of disorder.

METHOD

We recruited an ethnically-diverse sample of 304 (130 women) adults with recent histories of violence and/or drug use, who completed a substance use diagnostic interview, the Childhood Trauma Questionnaire, and a sex exchange questionnaire.

RESULTS

First, structural equation modeling revealed that childhood sexual and physical abuse were related to increased drug engagement in women and men, respectively, above the influence of early childhood contextual variables (e.g., neighborhood, family) and age. Second, sexual abuse was related to sex exchange, which in turn was related to drug use symptoms in women but not men.

CONCLUSIONS

These data provide empirical support for distinct trauma-related pathways to drug use problems in men and women, which has implications for gendered explanations and prevention approaches.

Limits of Current Approaches to Diagnosis Severity Based on Criterion Counts: An Example with DSM-5 Alcohol Use Disorder

Within DSM-5, some diagnoses are now associated with a severity gradient based on the number of diagnostic criteria satisfied. Reasons for questioning the validity of this approach include the implicit assumptions of equal criterion severity and strict additivity of criteria combinations. To assess the implications of heterogeneity of criterion configurations on severity grading, we examined the association between all observed combinations of DSM-5 alcohol use disorder criteria endorsement, at each level of number of criteria endorsed, and multiple validity measures among 22,177 past-year drinkers from Wave 2 of the NESARC. Substantial variability of implied severity across criteria combinations was observed at each level of endorsement, with nontrivial overlap in implied severity across criterion counts. Findings suggest severity indices are at best imprecise and, potentially, misleading. These problems are likely inherent in traditional polythetic approaches to diagnosis and almost certainly applicable to other disorders. Approaches for improving severity grading are proposed.