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Classification of alcohol and drug problems
Classification and Epidemiology
Classification of alcohol and drug problems
The development of classification systems There is a spectrum of substance use behaviours, and over the past century observers have taken various different approaches in understanding and describing them. Disease model – as early as the 1870s the concept of alcoholism as a disease was emerging but it was finally well described by Jellinek, a US physician, in the 1940s. Indeed, Alcoholics Anonymous (AA) continues to use the disease model in its 12-step approach and it is an integral part of the organization’s philosophy. The disease model allows individuals with substance-related problems to be diagnosed categorically and subsequently treated on the basis of the signs and symptoms they exhibit. Behavioural model – another view is of substance misuse as learned behaviour: an individual has learned to use the substance in the context of the society and culture in which he or she lives. This results in a more dimensional approach than the disease model and implies that cognitive–behavioural techniques may be taught to help an individual ‘unlearn’ substance-using behaviour.1 Socioeconomic model – sociologists have seen substance use as a product of the social and economic environment in which an individual finds himself. In the late 19th century, social hygienists identified a high prevalence of alcohol abuse among poorer people and sought to reduce it by education, resulting in the rise of the temperance movement.2,3 Since then, diagnostic systems that fail to take into account the social and cultural dimensions of substance misuse problems have been criticized.
Emily Finch Sarah Welch
Abstract Systems of classifying alcohol and drug problems have developed through the disease model of the 19th century, which allows categorical diagnosis and facilitated the 12-step approach to behavioural models and to socioeconomic models where substance use is seen as part of the environment in which an individual functions. DSM and ICD classified drug and alcohol use separately in their early versions, although they are now subject to the same criteria and both systems make a distinction between dependant and non-dependant use. DSM-IV and ICD-10 classify dependence as a cluster of cognitive, behavioural and physiological systems applicable across all substances. The criteria are broadly tolerance and withdrawal, impaired control and compulsion and salience and continued use despite harm. Dependence symptoms, substance-related problems and consumption form separate but related axes. Both DSM-IV and ICD-10 contain categories of abuse and harmful use respectively for substance users who do not meet the criteria for dependence. ICD-10 has a greater emphasis on the physical and psychological consequences of substance abuse. A substantial body of work on the validity of the dependence syndrome has generally found the dependence abuse model to be useful across the range of substances, although for cannabis the there are problems defining the withdrawal syndrome. Recent work to define DSM-V may change classification systems. Other forms of typology which are clinically useful also exist; for instance, the distinction between injecting and non-injecting drug users, and systems that detect substance-related problems rather than diagnostic criteria.
DSM and ICD classification Early classification systems viewed drug and alcohol use sep arately; indeed, DSM-I (published in 1952) classified alcoholism as one aspect of sociopathic personality disorder. The dependence syndrome was first proposed for alcohol use4 but was later applied to different substances (Table 1). The clinical description by Edwards and Gross gave equal weight to physical, psychological and behavioural factors such as: • impaired control over substance use • continued use despite harm • withdrawal symptoms • a way of life centred around the substance.
Keywords abuse; dependence; DSM-IV; harmful use; ICD-10
Emily Finch MD MRCPsych is a Consultant Psychiatrist and visiting Senior Lecturer at the South London and Maudsley NHS Trust and the Institute of Psychiatry, UK, and has clinical responsibility for the North Southwark community drug services as the Deputy Clinical Director. She is the National Treatment Agency Clinical team leader. Research interests include the outcome of treatment for opiate users, dual diagnosis, and coercive treatment. She lecturers and tutors on the MSc in clinical and public health of addiction. Conflicts of interest: none declared.
The dependence concept • Allows a non-judgemental approach • Focuses on treatment of the drink or drug problem • Predicts outcome • Is associated with higher consumption levels • Is associated with higher levels of substance-related problems • Indicates need for more intensive treatment (i.e. medically assisted detoxification) • Indicates need for abstinence (compared with controlled drinking) • Is flexible and describes a variety of clinical features • Is applicable to many different substances
Sarah Welch DPhil MRCPsych is a Consultant Psychiatrist in Substance Misuse for the Gloucestershire Partnership NHS Trust, UK. She qualified from Cambridge and Oxford Universities. She studied for her doctorate in Oxford and trained in psychiatry at the Bethlem and Maudsley Hospitals. She has held two consultant posts in substance misuse, one in the London Borough of Lambeth, and her current post in a contrasting rural area. She has a special interest in psychiatric comorbidity. Conflicts of interest: none declared.
PSYCHIATRY 5:12
Table 1
423
© 2006 Published by Elsevier Ltd.
Classification and Epidemiology
By the time ICD-9 and DSM-III were published (1978 and 1980, respectively), drug and alcohol dependence were subject to the same criteria and there was a distinction between dependent and non-dependent use.5 In the latest versions (ICD-10 (1992) and DSM-IV (1994)), there are few differences between the classification systems for both dependence and abuse (see Tables 2 and 3).6,7
all; for example, withdrawal symptoms are not applicable for hallucinogens. Tolerance and withdrawal Dependent individuals usually give an account of needing increasing amounts of the substance over time to produce the desired effect. This is especially seen in those abusing alcohol, opioids and stimulants, although there is substantial individual variation. Tolerance and withdrawal are both manifestations of a neuroadaptive state that develops in response to continuous and repeated exposure to the psychoactive substance. The development of tolerance and withdrawal is also affected by the environment in which the substance is taken, as demonstrated by substance users experiencing withdrawal symptoms when returning to a location where they have previously taken drugs.
Dependence: core concepts The dependence syndrome is a cluster of cognitive, behavioural and physiological symptoms, which are described in both DSMIV and ICD-10 (see Table 2). The two systems are similar in that all criteria are given the same weight and none are essential for the diagnosis. Both require that three criteria are met over a period of 12 months. A diagnosis of dependence can be applied to all classes of substance, including: • alcohol • opioids • cocaine and other stimulants (e.g. amphetamines) • benzodiazepines • hallucinogens • nicotine. The same criteria can used for all substances but some will be less relevant to certain substances or even not apply at
Impaired control and compulsion Substance users have difficulties setting limits on their use. This is often associated with unsuccessful attempts to cut down or give up the substance, as well as a persistent desire to stop using it. Salience and continued use despite harm Salience refers to the fact that individuals give the substance a higher priority than other interests or obligations. They will often
ICD-10 and DSM-IV classifications of the dependence syndrome ICD-10
DSM-IV
Evidence of tolerance such that increased doses of the psychoactive substance are required in order to achieve effects originally produced by lower doses
Tolerance as defined by either of the following: • need for markedly increased amounts of the substance to achieve intoxication or desired effect • markedly diminished effect with continued use of the same amount of substance
A physiological withdrawal state when substance use has ceased or been reduced, as evidenced by: • the characteristic withdrawal syndrome for the substance, or • use of the same (or a closely related) substance with the intention of relieving or avoiding withdrawal symptoms
Withdrawal as manifested by either of the following: • the characteristic withdrawal syndrome for the substance • the same (or closely related) substance is taken to relieve or avoid withdrawal symptoms
A strong desire or sense of compulsion to take the substance
No equivalent criterion
No equivalent criterion
There is a persistent desire or unsuccessful efforts to cut down or control substance use
Difficulties in controlling substance-taking behaviour in terms of its onset, termination or levels of use
The substance is often taken in larger amounts or over a longer period than was intended
Progressive neglect of alternative pleasures or interests because of psychoactive substance use
Important social, occupational or recreational activities are given up or reduced because of substance use
Increased amount of time necessary to obtain or take the substance or recover from its effects
A great deal of time is spent in activities necessary to obtain the substance, use the substance or recover from its effects
Persisting with substance use despite clear evidence of overtly harmful consequences. Efforts should be made to determine that the user was actually, or could be expected to be, aware of the nature and extent of the harm
The substance use is continued despite knowledge of having a persistent or recurrent physical and psychological problem likely to have been caused or exacerbated by the substance
Table 2
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© 2006 Published by Elsevier Ltd.
Classification and Epidemiology
Validity of the dependence syndrome
ICD-10 and DSM-IV criteria for harmful use and substance abuse
As the early development of the concept of the dependence syndrome focused on alcohol, it is not surprising that the present definitions of dependence sometimes seem to ‘fit’ alcohol better than some other commonly misused substances. There has been relatively little controversy regarding the use of this framework for opioid use, given the readily observed increase in tolerance to opioids among regular users and the characteristic physiological signs of withdrawal. Such features are also clearly recognizable in long-term users of benzodiazepines. However, the relevance of the concept of dependence to drugs such as cocaine, amphetamines, cannabis and nicotine has been less certain. Studies examining the content validity of the classificatory systems have often focused on treatment samples with extreme levels of symptomatology, and have been complicated by the effects of polydrug use. However, a large study of alcohol, opioid, cocaine and cannabis users conducted by the World Health Organization (WHO) in 12 countries,8 using both treatment and non-treatment settings, found the dependence and abuse constructs to be broadly generalizable across all four categories of substance. The study supported the organization of criteria into two diagnostic categories (dependence and abuse) for alcohol, opioids and cannabis, but found that cocaine users better fitted a unidimensional model. This study also showed that within some user populations, specific criteria played a greater or lesser role in defining the latent construct. For example, the experience of withdrawal played a stronger role in defining dependence among opioid users than among users of the other substances; experien cing increased tolerance and using more than they intended were prominent criteria among cocaine users. In practice, different features of the syndrome may therefore carry different ‘weight’ for different substances. The WHO study did not address classification of nicotine-use disorders. However, a separate investigation on a smaller sample of daily smokers also found that a two-factor model best fitted the observed data, though the two factors were described as ‘general dependence’ and ‘failed cessation’.9 Recent research on long-term cannabis use has provided further support for the validity of a dependence syndrome as applied to cannabis users,10,11 although the definition of a clear withdrawal syndrome remains undetermined.12 DSM-V is now being planned. As part of that process consideration is being given to changes such as the reintroduction of the word ‘addiction’ and the addition of a dimensional element to the classification of substance use disorders.13,14
ICD-10 criteria for harmful use A pattern of psychoactive substance abuse that is causing damage to health, either physical or mental. The diagnosis requires that actual damage should have been caused to the mental or physical health of the user. Socially negative consequences, or the disapproval of others are not in themselves evidence of harmful use DSM-IV criteria for substance abuse • Recurrent substance use resulting in a failure to fulfil major role obligations at work, school or home • Recurrent substance abuse in situations in which it is physically hazardous • Recurrent substance-related legal problems • Continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance Table 3
describe previous hobbies or interests that they have stopped doing since increasing their substance use. The criterion of continued use despite harmful consequences can be applied only if the person is aware of the causal relationship between the substance use and the resulting harm.
The relationship between dependence, consumption and problems Dependence symptoms, substance-related problems and consumption form separate but related axes. However, the relationship between them may not be a simple one; for example, one problem drinker may have high levels of daily consumption, dependence symptoms and few alcohol-related problems, while another may binge-drink large amounts of alcohol at weekends only, have few dependence symptoms yet have serious alcoholrelated problems, such as violence when drunk.
Abuse and harmful use: core concepts ‘Substance abuse’ (DSM-IV) and ‘harmful use’ (ICD-10) describe substance users who have problems related to their substance use but who do not meet the criteria for dependence (see Table 3). The two diagnostic systems differ substantially. • DSM-IV emphasizes the negative social consequences of the substance use. • ICD-10 specifically excludes socially negative consequences and emphasizes physical and mental consequences. The result is that ICD-10 harmful use is a more socially stable syndrome that can exist across different cultures. An individual who is drinking heavily and is socially stable but develops liver disease may fulfil criteria for harmful use but not abuse, while a cocaine user arrested after causing a car crash may fulfil criteria for abuse but not harmful use.
PSYCHIATRY 5:12
Other forms of classification As well as the two main international systems of classification (ICD-10 and DSM-IV) there are other typologies, both formal and informal, which are used in research and clinical settings to describe and attempt to understand problems relating to substance misuse. For example, a distinction is often made between injecting drug users and those who do not inject. This distinction can be made separately from the concepts of dependence and abuse, and is of practical significance since injecting drug users are at risk of a wide range of physical complications unrelated to 425
© 2006 Published by Elsevier Ltd.
Classification and Epidemiology
drug use by other routes. Other approaches concentrate more on classifying problems related to substance use, and are useful in planning and prioritizing interventions. This has led to the development of instruments such as the Alcohol Problems Questionnaire,15,16 which assess problems rather than diagnostic criteria. Such instruments can be used separately from or in conjunction with instruments that assess dependence. ◆
7 American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). 4th edn. Washington, DC: American Psychiatric Association, 1994. 8 Nelson CB, Rehm J, Bedirhan Ustun T, et al. Factor structures of DSM-IV substance disorder criteria endorsed by alcohol, cannabis, cocaine and opiate users: results from the WHO reliability and validity criteria. Addiction 1999; 94: 843–55. 9 Johnson EO, Breslau N, Anthony JC. The latent dimensionality of DIS/DSM-III-R nicotine dependence: exploratory analyses. Addiction 1996; 91: 583–88. 10 Swift W, Hall W, Copeland J. One-year follow-up of cannabis dependence of long-term users in Sydney, Australia. Drug Alcohol Depend 2000; 59: 309–18. 11 Swift W, Hall W, Teeson M. Characteristics of DSM-IV and ICD-10 cannabis dependence among Australian adults: results from the National Survey of Mental Health and Well-being. Drug Alcohol Depend 2001; 63: 147–53. 12 Smith NT. A review of the published literature into cannabis withdrawal symptoms in human users. Addiction 2002; 97: 621–32. 13 O’Brien CP, Volkow N, Li T-K. What’s in a word? Addiction versus dependence in DSM-V. Am J Psychiatry 2006; 163: 764–65. 14 Helzer JE, van den Brink W, Guth SE. Should there be both categorical and dimensional criteria for the substance use disorders in DSM V. Addiction 2006; 101: 17–22. 15 Drummond DC. The relationship between alcohol dependence and alcohol-related problems in a clinical population. Br J Addict 1990; 85: 357–66. 16 Williams BTR, Drummond DC. The Alcohol Problems Questionnaire: reliability and validity. Drug Alcohol Depend 1994; 35: 239–43.
References 1 Heather N, Robertson I. Problem drinking. Oxford: Oxford University Press, 1989. 2 Berridge V. Dependence: historical concepts and constructs. In: Edwards G, Lader M, eds. The nature of drug dependence. Oxford: Oxford University Press, 1990. 3 Edwards G, Marshall EJ, Cook CCH. The treatment of drinking problems: a guide for the helping professions. 4th edn. Cambridge: Cambridge University Press, 2003. 4 Edwards G, Gross MM. Alcohol dependence: provisional description of a clinical syndrome. Br Med J 1976; 1: 1058–61. 5 Marshall EJ. Alcohol dependence and alcohol problems. In: Gelder MG, López-Ibor Jr. JJ, Andreasen NC, eds. New Oxford textbook of psychiatry. Oxford: Oxford University Press, 2000. 6 World Health Organization. International Classification of Diseases (ICD-10). 10th edn. Geneva: World Health Organization, 1992.
PSYCHIATRY 5:12
426
© 2006 Published by Elsevier Ltd.
Classification of alcohol and drug problems
The development of classification systems There is a spectrum of substance use behaviours, and over the past century observers have taken various different approaches in understanding and describing them. Disease model – as early as the 1870s the concept of alcoholism as a disease was emerging but it was finally well described by Jellinek, a US physician, in the 1940s. Indeed, Alcoholics Anonymous (AA) continues to use the disease model in its 12-step approach and it is an integral part of the organization’s philosophy. The disease model allows individuals with substance-related problems to be diagnosed categorically and subsequently treated on the basis of the signs and symptoms they exhibit. Behavioural model – another view is of substance misuse as learned behaviour: an individual has learned to use the substance in the context of the society and culture in which he or she lives. This results in a more dimensional approach than the disease model and implies that cognitive–behavioural techniques may be taught to help an individual ‘unlearn’ substance-using behaviour.1 Socioeconomic model – sociologists have seen substance use as a product of the social and economic environment in which an individual finds himself. In the late 19th century, social hygienists identified a high prevalence of alcohol abuse among poorer people and sought to reduce it by education, resulting in the rise of the temperance movement.2,3 Since then, diagnostic systems that fail to take into account the social and cultural dimensions of substance misuse problems have been criticized.
Emily Finch Sarah Welch
Abstract Systems of classifying alcohol and drug problems have developed through the disease model of the 19th century, which allows categorical diagnosis and facilitated the 12-step approach to behavioural models and to socioeconomic models where substance use is seen as part of the environment in which an individual functions. DSM and ICD classified drug and alcohol use separately in their early versions, although they are now subject to the same criteria and both systems make a distinction between dependant and non-dependant use. DSM-IV and ICD-10 classify dependence as a cluster of cognitive, behavioural and physiological systems applicable across all substances. The criteria are broadly tolerance and withdrawal, impaired control and compulsion and salience and continued use despite harm. Dependence symptoms, substance-related problems and consumption form separate but related axes. Both DSM-IV and ICD-10 contain categories of abuse and harmful use respectively for substance users who do not meet the criteria for dependence. ICD-10 has a greater emphasis on the physical and psychological consequences of substance abuse. A substantial body of work on the validity of the dependence syndrome has generally found the dependence abuse model to be useful across the range of substances, although for cannabis the there are problems defining the withdrawal syndrome. Recent work to define DSM-V may change classification systems. Other forms of typology which are clinically useful also exist; for instance, the distinction between injecting and non-injecting drug users, and systems that detect substance-related problems rather than diagnostic criteria.
DSM and ICD classification Early classification systems viewed drug and alcohol use sep arately; indeed, DSM-I (published in 1952) classified alcoholism as one aspect of sociopathic personality disorder. The dependence syndrome was first proposed for alcohol use4 but was later applied to different substances (Table 1). The clinical description by Edwards and Gross gave equal weight to physical, psychological and behavioural factors such as: • impaired control over substance use • continued use despite harm • withdrawal symptoms • a way of life centred around the substance.
Keywords abuse; dependence; DSM-IV; harmful use; ICD-10
Emily Finch MD MRCPsych is a Consultant Psychiatrist and visiting Senior Lecturer at the South London and Maudsley NHS Trust and the Institute of Psychiatry, UK, and has clinical responsibility for the North Southwark community drug services as the Deputy Clinical Director. She is the National Treatment Agency Clinical team leader. Research interests include the outcome of treatment for opiate users, dual diagnosis, and coercive treatment. She lecturers and tutors on the MSc in clinical and public health of addiction. Conflicts of interest: none declared.
The dependence concept • Allows a non-judgemental approach • Focuses on treatment of the drink or drug problem • Predicts outcome • Is associated with higher consumption levels • Is associated with higher levels of substance-related problems • Indicates need for more intensive treatment (i.e. medically assisted detoxification) • Indicates need for abstinence (compared with controlled drinking) • Is flexible and describes a variety of clinical features • Is applicable to many different substances
Sarah Welch DPhil MRCPsych is a Consultant Psychiatrist in Substance Misuse for the Gloucestershire Partnership NHS Trust, UK. She qualified from Cambridge and Oxford Universities. She studied for her doctorate in Oxford and trained in psychiatry at the Bethlem and Maudsley Hospitals. She has held two consultant posts in substance misuse, one in the London Borough of Lambeth, and her current post in a contrasting rural area. She has a special interest in psychiatric comorbidity. Conflicts of interest: none declared.
PSYCHIATRY 5:12
Table 1
423
© 2006 Published by Elsevier Ltd.
Classification and Epidemiology
By the time ICD-9 and DSM-III were published (1978 and 1980, respectively), drug and alcohol dependence were subject to the same criteria and there was a distinction between dependent and non-dependent use.5 In the latest versions (ICD-10 (1992) and DSM-IV (1994)), there are few differences between the classification systems for both dependence and abuse (see Tables 2 and 3).6,7
all; for example, withdrawal symptoms are not applicable for hallucinogens. Tolerance and withdrawal Dependent individuals usually give an account of needing increasing amounts of the substance over time to produce the desired effect. This is especially seen in those abusing alcohol, opioids and stimulants, although there is substantial individual variation. Tolerance and withdrawal are both manifestations of a neuroadaptive state that develops in response to continuous and repeated exposure to the psychoactive substance. The development of tolerance and withdrawal is also affected by the environment in which the substance is taken, as demonstrated by substance users experiencing withdrawal symptoms when returning to a location where they have previously taken drugs.
Dependence: core concepts The dependence syndrome is a cluster of cognitive, behavioural and physiological symptoms, which are described in both DSMIV and ICD-10 (see Table 2). The two systems are similar in that all criteria are given the same weight and none are essential for the diagnosis. Both require that three criteria are met over a period of 12 months. A diagnosis of dependence can be applied to all classes of substance, including: • alcohol • opioids • cocaine and other stimulants (e.g. amphetamines) • benzodiazepines • hallucinogens • nicotine. The same criteria can used for all substances but some will be less relevant to certain substances or even not apply at
Impaired control and compulsion Substance users have difficulties setting limits on their use. This is often associated with unsuccessful attempts to cut down or give up the substance, as well as a persistent desire to stop using it. Salience and continued use despite harm Salience refers to the fact that individuals give the substance a higher priority than other interests or obligations. They will often
ICD-10 and DSM-IV classifications of the dependence syndrome ICD-10
DSM-IV
Evidence of tolerance such that increased doses of the psychoactive substance are required in order to achieve effects originally produced by lower doses
Tolerance as defined by either of the following: • need for markedly increased amounts of the substance to achieve intoxication or desired effect • markedly diminished effect with continued use of the same amount of substance
A physiological withdrawal state when substance use has ceased or been reduced, as evidenced by: • the characteristic withdrawal syndrome for the substance, or • use of the same (or a closely related) substance with the intention of relieving or avoiding withdrawal symptoms
Withdrawal as manifested by either of the following: • the characteristic withdrawal syndrome for the substance • the same (or closely related) substance is taken to relieve or avoid withdrawal symptoms
A strong desire or sense of compulsion to take the substance
No equivalent criterion
No equivalent criterion
There is a persistent desire or unsuccessful efforts to cut down or control substance use
Difficulties in controlling substance-taking behaviour in terms of its onset, termination or levels of use
The substance is often taken in larger amounts or over a longer period than was intended
Progressive neglect of alternative pleasures or interests because of psychoactive substance use
Important social, occupational or recreational activities are given up or reduced because of substance use
Increased amount of time necessary to obtain or take the substance or recover from its effects
A great deal of time is spent in activities necessary to obtain the substance, use the substance or recover from its effects
Persisting with substance use despite clear evidence of overtly harmful consequences. Efforts should be made to determine that the user was actually, or could be expected to be, aware of the nature and extent of the harm
The substance use is continued despite knowledge of having a persistent or recurrent physical and psychological problem likely to have been caused or exacerbated by the substance
Table 2
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© 2006 Published by Elsevier Ltd.
Classification and Epidemiology
Validity of the dependence syndrome
ICD-10 and DSM-IV criteria for harmful use and substance abuse
As the early development of the concept of the dependence syndrome focused on alcohol, it is not surprising that the present definitions of dependence sometimes seem to ‘fit’ alcohol better than some other commonly misused substances. There has been relatively little controversy regarding the use of this framework for opioid use, given the readily observed increase in tolerance to opioids among regular users and the characteristic physiological signs of withdrawal. Such features are also clearly recognizable in long-term users of benzodiazepines. However, the relevance of the concept of dependence to drugs such as cocaine, amphetamines, cannabis and nicotine has been less certain. Studies examining the content validity of the classificatory systems have often focused on treatment samples with extreme levels of symptomatology, and have been complicated by the effects of polydrug use. However, a large study of alcohol, opioid, cocaine and cannabis users conducted by the World Health Organization (WHO) in 12 countries,8 using both treatment and non-treatment settings, found the dependence and abuse constructs to be broadly generalizable across all four categories of substance. The study supported the organization of criteria into two diagnostic categories (dependence and abuse) for alcohol, opioids and cannabis, but found that cocaine users better fitted a unidimensional model. This study also showed that within some user populations, specific criteria played a greater or lesser role in defining the latent construct. For example, the experience of withdrawal played a stronger role in defining dependence among opioid users than among users of the other substances; experien cing increased tolerance and using more than they intended were prominent criteria among cocaine users. In practice, different features of the syndrome may therefore carry different ‘weight’ for different substances. The WHO study did not address classification of nicotine-use disorders. However, a separate investigation on a smaller sample of daily smokers also found that a two-factor model best fitted the observed data, though the two factors were described as ‘general dependence’ and ‘failed cessation’.9 Recent research on long-term cannabis use has provided further support for the validity of a dependence syndrome as applied to cannabis users,10,11 although the definition of a clear withdrawal syndrome remains undetermined.12 DSM-V is now being planned. As part of that process consideration is being given to changes such as the reintroduction of the word ‘addiction’ and the addition of a dimensional element to the classification of substance use disorders.13,14
ICD-10 criteria for harmful use A pattern of psychoactive substance abuse that is causing damage to health, either physical or mental. The diagnosis requires that actual damage should have been caused to the mental or physical health of the user. Socially negative consequences, or the disapproval of others are not in themselves evidence of harmful use DSM-IV criteria for substance abuse • Recurrent substance use resulting in a failure to fulfil major role obligations at work, school or home • Recurrent substance abuse in situations in which it is physically hazardous • Recurrent substance-related legal problems • Continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance Table 3
describe previous hobbies or interests that they have stopped doing since increasing their substance use. The criterion of continued use despite harmful consequences can be applied only if the person is aware of the causal relationship between the substance use and the resulting harm.
The relationship between dependence, consumption and problems Dependence symptoms, substance-related problems and consumption form separate but related axes. However, the relationship between them may not be a simple one; for example, one problem drinker may have high levels of daily consumption, dependence symptoms and few alcohol-related problems, while another may binge-drink large amounts of alcohol at weekends only, have few dependence symptoms yet have serious alcoholrelated problems, such as violence when drunk.
Abuse and harmful use: core concepts ‘Substance abuse’ (DSM-IV) and ‘harmful use’ (ICD-10) describe substance users who have problems related to their substance use but who do not meet the criteria for dependence (see Table 3). The two diagnostic systems differ substantially. • DSM-IV emphasizes the negative social consequences of the substance use. • ICD-10 specifically excludes socially negative consequences and emphasizes physical and mental consequences. The result is that ICD-10 harmful use is a more socially stable syndrome that can exist across different cultures. An individual who is drinking heavily and is socially stable but develops liver disease may fulfil criteria for harmful use but not abuse, while a cocaine user arrested after causing a car crash may fulfil criteria for abuse but not harmful use.
PSYCHIATRY 5:12
Other forms of classification As well as the two main international systems of classification (ICD-10 and DSM-IV) there are other typologies, both formal and informal, which are used in research and clinical settings to describe and attempt to understand problems relating to substance misuse. For example, a distinction is often made between injecting drug users and those who do not inject. This distinction can be made separately from the concepts of dependence and abuse, and is of practical significance since injecting drug users are at risk of a wide range of physical complications unrelated to 425
© 2006 Published by Elsevier Ltd.
Classification and Epidemiology
drug use by other routes. Other approaches concentrate more on classifying problems related to substance use, and are useful in planning and prioritizing interventions. This has led to the development of instruments such as the Alcohol Problems Questionnaire,15,16 which assess problems rather than diagnostic criteria. Such instruments can be used separately from or in conjunction with instruments that assess dependence. ◆
7 American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). 4th edn. Washington, DC: American Psychiatric Association, 1994. 8 Nelson CB, Rehm J, Bedirhan Ustun T, et al. Factor structures of DSM-IV substance disorder criteria endorsed by alcohol, cannabis, cocaine and opiate users: results from the WHO reliability and validity criteria. Addiction 1999; 94: 843–55. 9 Johnson EO, Breslau N, Anthony JC. The latent dimensionality of DIS/DSM-III-R nicotine dependence: exploratory analyses. Addiction 1996; 91: 583–88. 10 Swift W, Hall W, Copeland J. One-year follow-up of cannabis dependence of long-term users in Sydney, Australia. Drug Alcohol Depend 2000; 59: 309–18. 11 Swift W, Hall W, Teeson M. Characteristics of DSM-IV and ICD-10 cannabis dependence among Australian adults: results from the National Survey of Mental Health and Well-being. Drug Alcohol Depend 2001; 63: 147–53. 12 Smith NT. A review of the published literature into cannabis withdrawal symptoms in human users. Addiction 2002; 97: 621–32. 13 O’Brien CP, Volkow N, Li T-K. What’s in a word? Addiction versus dependence in DSM-V. Am J Psychiatry 2006; 163: 764–65. 14 Helzer JE, van den Brink W, Guth SE. Should there be both categorical and dimensional criteria for the substance use disorders in DSM V. Addiction 2006; 101: 17–22. 15 Drummond DC. The relationship between alcohol dependence and alcohol-related problems in a clinical population. Br J Addict 1990; 85: 357–66. 16 Williams BTR, Drummond DC. The Alcohol Problems Questionnaire: reliability and validity. Drug Alcohol Depend 1994; 35: 239–43.
References 1 Heather N, Robertson I. Problem drinking. Oxford: Oxford University Press, 1989. 2 Berridge V. Dependence: historical concepts and constructs. In: Edwards G, Lader M, eds. The nature of drug dependence. Oxford: Oxford University Press, 1990. 3 Edwards G, Marshall EJ, Cook CCH. The treatment of drinking problems: a guide for the helping professions. 4th edn. Cambridge: Cambridge University Press, 2003. 4 Edwards G, Gross MM. Alcohol dependence: provisional description of a clinical syndrome. Br Med J 1976; 1: 1058–61. 5 Marshall EJ. Alcohol dependence and alcohol problems. In: Gelder MG, López-Ibor Jr. JJ, Andreasen NC, eds. New Oxford textbook of psychiatry. Oxford: Oxford University Press, 2000. 6 World Health Organization. International Classification of Diseases (ICD-10). 10th edn. Geneva: World Health Organization, 1992.
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© 2006 Published by Elsevier Ltd.