14_Semple_Chap14.indd 533 12/7/2012 3:43:49 PM This page intentionally left blank 535 Chapter 15 Substance misuse The psychiatry of substance misuse 536 Substance use and misuse 538 Substance misuse disord ers 540 The dependence syndrome 542 Stages of change and harm reduction 544 Alcohol misuse 546 Alcohol as a drug 548 Screening for alcohol problems 550 Assessment of the patient with alcohol problems 552 Giving drinking advice 554 Planning treatment in alcohol misuse 556 A lcohol withdrawal syndromes 558 Management of alcohol withdrawal 560 Maintenance interventi ons in alcohol misuse 1: psychological methods 562 Maintenance interventions in alcohol misuse 2: pharmacological methods 564 Alcohol misuse disorders 1 566 Alcohol misuse disorders 2 568 Psychiatric comorbidity 570 W ernicke \200\223Korsakoff syndrome 572 Medical complications of alcohol misuse 574 Illegal drugs 576 Street slang associated with drug misuse 578 Opiates/opioids 580 Depressants 582 Stimulants 584 Hallucinogens 586 Other drugs 588 Assessment of the drug user 592 Planning t reatment in drug misuse 594 Substitute prescribing 1: principles 596 Substitute prescribing 2: opiates 598 Substitute prescribing 3: benzodiazepines 600 Monitoring of maintenance pre scribing 602 Psychotic illnesses and substance misuse 604 Legal issues related to drug and alcohol misuse 606 15_Semple_Chap15.indd 535 12/7/2012 3:47:55 PM CHAPTER 15 Substance misuse 536 The psychiatry of substance misuse The subspecialty of substance misuse is concerned with t he assessment and treatment of patients with problems arising from the misuse of harm- ful or addictive substances. These include: (1) alcohol, (2) illegal or \200\230street \200 \231 drugs, (3) prescription and over-the-counter medicines, and (4) volatile chemicals. Th e resultant problems include both mental and physical ill- nesses and family, housing, empl oyment, and legal dif \201 culties. Both psy- chological and pharmacological interventions are used in treatment, which may include detoxi \201 cation and substitute prescribing. The majority of medical interventions in patients with substance use problems are undertake n by GPs. In areas where there are no substance misuse specialists, more complex cases are seen by general psychiatrists, with management of the acute medical problems, including ove rdose and withdrawals, treated in the general hospital. All psychiatrists will have ample o pportunity to see and develop skills in treating patients with sub- stance misuse. Around the UK there is variable service provision for drug and alcohol misuse. Some service s will restrict themselves to the primary substance misuse, while others will address all m ental health needs. Specialists tend to work alongside voluntary and non-medical treatment agencies, many of which provide a good and vital service. Strong links between psychiatry/ substance use services and non-medical agencies should be fostered. Drug treatment services within the health care system make up only one part of the wider ra nge of centrally and locally funded and volunteer services for problem drug users. Within t he health service the majority of service provision is within primary care, who will have a variable degree of experience of (and enthusiasm for) such work. The availability of speci alist services will vary by area and setting (e.g. rural/urban) and may range from the spec ial interest of an individual psychiatrist or GP, to a specialist serv- ice with support st aff and dedicated facilities. Local pharmacists can also be a useful resource in supervisin g consumption of substitute drugs. Non-health care provision will also vary by setting, though may include: advice shops offer ing lea \202 ets and education about drugs and harm reduction strategies; self-help groups , some adhering to an Alcoholics Anonymous (AA)-style \200\230twelve-step approach \200 \231, usually involving peer sup- port from ex-users; and residential rehabilitation facili ties, offering detoxi- \201 cation and abstinence programs. The practitioner working in t he \201 eld of drug misuse should develop an awareness of these services and their referr al criteria and encourage a collaborative and co-ordinated approach to patient management. 15_Semple_Chap15.indd 536 12/7/2012 3:47:55 PM THE PSYCHIATRY OF SUBSTANCE MISUSE 537 The skills required for those working in the \201 eld of substance misuse are: \200 Knowledge of the psychiatric symptoms and syndromes associated with substance misuse This i ncludes the effects of substance misuse on the brain, in causing psychiatric symptoms, and the effects of substance misuse on pre-existing mental and physical illness. Knowledge and understanding of the in \202 uence of psychological and social factors on substance misuse and relapse. Experience of interviewing and counseling methods Skills in interviewing and motivating patients who may have very ambivalent feelings about changing their behavior. Ex perience of available pharmacological and psychological treatment methods An area undergoin g constant development, where there is a need to keep abreast of changes in evidence. Aware ness of the culture and pattern of drug use within a community Patterns of drug use change over time, and the types and strengths of drugs available in a community will also change d ynamically. Information from police and the voluntary sector can be helpful here. Willingne ss to be involved with other agencies \201 eld of substance misuse is done by agencies ou tside the health care system. Practitioners should attempt to understand the work of these agencies, and refer to them where appropriate. Understanding of the natural history of subs tance misuse/addiction Substance misuse disorders can be chronic, and at times lifelong, wi th a relapsing/remitting course (like many psychiatric conditions). Taking a long-term appr oach is therefore essential. Ability to consider health in its wider context Substance misu se gives rise to health risks beyond the effect of the drug (e.g. drink driving deaths, HIV infection). In addition, it is a community problem leading to lost productivity, crime, ro ad accidents, violence, and family break-up. Consideration of change beyond change in an in dividual patient Patterns of substance misuse in a society are susceptible to political man ipulation (e.g. licensing hours, decriminalization, legalization, availability of treatment services). One role of substance misuse specialists is to understand these factors and to present the case for political change. Valuable work in the A non-judgemental approach. Sometimes there is a perception that drug or alcohol users are \200\230dif \201 cult \200\231 patients to treat. Bear in mind GMC guide- lines direct th at it is \200\230unethical for a doctor to withhold treatment from any patient on the basi s of a moral judgment that the patient \200\231s activities or lifestyle may have contribut ed to the conditions for which treatment was being sought \200\231. Note: for the purposes of this chapter, we refer to alcohol misuse and drug misuse separate ly and refer to them collectively as substance mis- use. Alcohol is of course a drug and sh ould be thought of as such, but we believe this terminology to be clearer and more understa ndable to patients. 15_Semple_Chap15.indd 537 12/7/2012 3:47:56 PM CHAPTER 15 Substance misuse 538 Substance use and misuse \200\230Humankind cannot bear very much reality \200\231 T.S. Eli ot \200\230The urge to escape, the longing to transcend themselves, if only for a few minutes , is and always has been one of the principal appetites of the soul. \200\231 Aldous Huxley People in all cultures, at all times throughout history, have sought out mood or perception -altering substances. 25% of adults smoke; 90% drink alcohol; 33% have lifetime experience of one illegal drug (mostly canna- bis). Society \200\231s attitude to substance use and to those with substance use problems has varied, from prohibition and condemnation to toleran ce and treatment. Within British society at the moment caffeine use is legal and accepted; alcohol and tobacco use are accepted with legal limitations; and other substances have seve re legal limitations \200\224some available only on prescription, others not at all. Despit e this, the harmful effects of alcohol dwarf those of other drugs. Many of the abused substances subsequently described have been used in their naturally occu rring form throughout history (e.g. the chewing of coca leaves by Peruvian Indians). There has been a tendency for the development of more potent drug preparations which contain a hi gher concentration of the active ingredient (e.g. freebase cocaine), and the development of routes of administration which produce more rapid and intense effects (e.g. IV use). This has generally been associated with an increase in the attendant problems. Patients presenting with drug misuse problems represent only a small percentage of those wh o take drugs. Little is known about the non- presenting drug users. Their numbers may be hi nted at by community surveys, but they are otherwise poorly studied. It is clear, however, that the normal route from use of to abstinence from a substance is the indi- vidual decidi ng to discontinue use and then doing so, without medical consultation or help. Reasons given for substance use are varied, and may change over the course of a patient \200\231s life. They include: a search for a \200\230high \200\231; a search for a repeat of initial pleasurable effects; cultural norm in some subcultures; self-medication for anxi ety, social phobia, insomnia, symptoms of psychotic illness, and to prevent development of withdrawal symptoms. There is evi- dence for increased vulnerability to substance use in th ose with a family history of substance misuse, and the role of environmental stressors in p erpetuating use cannot be underplayed. The pattern of risks associated with substance use varies with the sub- stance taken, the d ose and route of administration, and the setting. They include: acute toxicity; behavioral toxicity (e.g. jumping from height due to believing one can \202 y); toxic effects of dru g contaminants; secondary medical problems; secondary psychiatric problems; risk of develop ment of dependency; and negative social, occupational, marital, and forensic consequences. 15_Semple_Chap15.indd 538 12/7/2012 3:47:56 PM This page intentionally left blank CHAPTER 15 Substance misuse 540 Substance misuse disorders Acute intoxication The pattern of reversible physical and mental abnormalities caused by the direct effects of the substance. These are speci \201 c and c haracteristic for each substance (e.g. disinhibition and ataxia for alcohol, euphoria and v isual sensory distortions for LSD). Most substances have both pleasurable and unpleasant ac ute effects; for some, the balance of positive and negative effects is situation-, dose-, a nd route- dependent. At-risk use A pattern of substance use where the person is at increase d risk of harming their physical or mental health. This is not a discrete point but shades into both normal consumption and harmful use. At-risk use depends not only on absolute amou nts taken but also on the situations and associated behaviors (e.g. any alcohol use is risk y if associated with driving). Harmful use The continuation of substance use despite eviden ce of damage to the user \200\231s physical or mental health or to their social, occupation al, and familial well-being. This damage may be denied or minimized by the individual conce rned. Dependence The layman \200\231s \200\230addiction \200\231. Encompasses a range of f eatures initially described in connection with alcohol abuse (b p. 542), now recognized as a syndrome associated with a range of substances. Dependence includes both physical depende nce (the physical adaptations to chronic, regular use) and psychological dependence (the be havioral adaptations). In some drugs (e.g. hallucinogens), no physical dependence features are seen. Withdrawal Where there is physical dependence on a drug, abstinence will generall y lead to features of withdrawal. These are characteristic for each drug. Some drugs are no t associated with any withdrawals; some with mild symptoms only; and some with signi \201 cant withdrawal syndromes. Clinically signi \201 cant withdrawals are recognized in depend ence on alcohol, opiates, nicotine, BDZs, amfetamines, and cocaine. Symptoms of withdrawal are often the \200\230opposite \200\231 of the acute effects of the drug (e.g. agitation a nd insomnia on BDZ withdrawal). Complicated withdrawal Withdrawals can be simple, or compli cated by the development of seizures, delirium, or psychotic features. Substance-induced ps ychotic disorder Illness characterized by hallucinations and/or delusions occurring as a di rect result of substance- induced neurotoxicity. Psychotic features may occur during intoxi cation and withdrawal states, or develop on a background of harmful or dependent use. There may be diagnostic confusion between these patients and those with primary psychotic illnes s and comorbid substance misuse. Substance-induced illnesses will be associated in time wit h episodes of substance misuse, will occur more readily with speci \201 c substances (e.g. cocaine) and may have atypical clinical features (e.g. late \201 rst presentation with p sychosis, prominence of non-auditory hallucinations). 15_Semple_Chap15.indd 540 12/7/2012 3:47:56 PM SUBSTANCE MISUSE DISORDERS 541 Cognitive impairment syndromes Reversible cognitive de \201 cits occur during intoxication . Persisting impairment (in some cases amounting to dementia) caused by chronic substance u se is recognized for alcohol, volatile chemicals, BDZs, and, debatably, cannabis. Cognitive impairment is associated with heavy chronic harmful use/dependence and shows gradual deter ioration with continued use and either a halt in the rate of decline, or gradual improvemen t with abstinence. Residual disorders Several conditions exist (e.g. alcoholic hallucinosis , b p. 568; persisting drug-induced psychosis, b p. 604; LSD \202 ashbacks, b p. 586) whe re there are continuing symptoms despite continuing abstinence from the drug. Exacerbation of pre-existing disorder All other psychiatric illnesses, especially anxiety and panic diso rders, mood disorders, and psychotic illnesses may be associated with comorbid substance us e. Although this may result in exacerbation of the patient \200\231s symptoms and a decline in treatment effectiveness, it can be understood as a desire to self- medicate (e.g. alcoh ol taken as a hypnotic in depressive illness) or escape unpleasant symptoms (e.g. opiates t aken to \200\230blot out \200\231 derogatory auditory hallucinations). Sometimes there is debate about whether there is, for example, a primary mood disorder with secondary alcohol use or vise versa. Careful examination of the time course of the illness may reveal the ans wer. In any case, it is advisable to address substance misuse problems \201 rst, as this may produce secondary mood improvements and continuing substance misuse will limit antidepr essant treatment effectiveness. 15_Semple_Chap15.indd 541 12/7/2012 3:47:56 PM CHAPTER 15 Substance misuse 542 The dependence syndrome This is a clinical syndrome describing the features of substance de pend- ence. It was described initially by Edwards and Gross1 as a provisional description o f alcohol dependence, but may be applied to the description of drug dependence. These featu res form the core of both ICD-10 and DSM-IV descriptions of substance dependence. \200 Primacy of drug-seeking behavior Also called \200\230salience \200\231 of drug use. The dr ug and the need to obtain it become the most important things in the person \200\231s life, taking priority over all other activities and interests. Thus drug use becomes more import ant than retaining job or relationships, remaining \201 nancially solvent and in good phy sical health, and may diminish moral sense leading to criminal activity and fraud. This dim inishes the \200\230holds \200\231 on a person \200\231s continued use. If he rates drug u se above health, then stern warnings about impending illness are likely to mean little. Nar rowing of the drug-taking repertoire a range of drugs to a single drug taken in preference to all others. The setting of drug use, the route of use, and the individuals with whom the drug is taken may also become stereotyped. Increased tolerance to the effects of the drug that more of the drug must be taken to achieve the same effects. They may also attempt to c ombat increasing tolerance by choosing a more rapidly acting route of administration (e.g. IV rather than smoked), or by choosing a more rapidly acting form (e.g. freebase cocaine ra ther than cocaine hydrochloride). In advanced dependence there may be a sudden loss of prev ious tolerance; the mechanism for this is unknown. Clinically, tolerance is exhibited by in dividuals who are able to display no or few signs of intoxication while at a blood level in which intoxication would be evident in a non-dependent individual. Loss of control of cons umption restrict further consumption once the drug is taken. Signs of withdrawal on attempt ed abstinence syndrome, characteristic for each drug, may develop. This may be only regular ly experienced in the mornings because at all other times the blood level is kept above the required level. Drug taking to avoid development of withdrawal symptoms The user learns to anticipate and avoid withdrawals (e.g. having the drug available on waking). Continued dru g use despite negative consequences The user persists in drug use even when threatened with signi \201 cant losses as a direct consequence of continued use (e.g. marital break-up, p rison term, loss of job). Rapid reinstatement of previous pattern of drug use after abstine nce Characteristically, when the user relapses to drug use after a period of abstinence, th ey are at risk of a return to the dependent pattern in a much shorter period than the time initially taken to reach dependent use. The user moves from The user \201 nds A subjective sense of inability to A withdrawal 1 Edwards G and Gross MM (1976) Alcohol dependence: provisional description of a clinical s yn- drome. Br Med J 1: 1058 \200\22361. 15_Semple_Chap15.indd 542 12/7/2012 3:47:56 PM This page intentionally left blank CHAPTER 15 Substance misuse 544 Stages of change and harm reduction Stages of change A model for understanding motivation a nd action towards change in harm- ful patterns of drug use was proposed by Prochaska and Di Clemente.1 Motivation is regarded as a prerequisite for and a precursor to action towards a bstinence or more controlled drug use. This model can be used when trying to tailor treatme nts to the individual. \200 Pre-contemplation exists, although this may be increasingly obvious to those around them. C ontemplation begins to look at both the positive and negative aspects of continued drug use . Decision drug use or attempt change. Action The point of motivation, where the user attem pts change. A variety of routes exist by which change may be attempted, which may or may no t include medical services. Maintenance improve those areas of life harmed by drug use. Rel apse gaining useful strategies to extend the maintenance period on the user \200\231s next attempt. The user does not recognize that problem use The user may accept that there is a problem and The point at which the user decides on whether to continue A stage of maintaining gains made and attempting to A return to previous behavior, but with the possibility of Harm reduction Harm reduction is a method of managing drug users in which it is accepted th at steps can be taken to reduce the mortality and morbidity for the user without necessaril y insisting on abstinence from drugs. This approach gained currency during the 1980s in an attempt to halt the projected AIDS epidemic. The majority of patients will present before a bstinence is a real- istic or achievable goal for them. Optimum care for this group of pati ents will involve engaging them with the service, exploring and encouraging motivation to c hange, and suggesting harm reduction strategies. Examples of such strategies include: \200 \200 \200 \200 Advice directed at use of safer drugs or routes of administration. Advice regarding safer i njecting practice ( Advice regarding safe sex. Prescription of maintenance opiates (substit ution prescribing) or BDZs. Assessment and treatment of comorbid physical or mental illness . Engagement with other sources of help (e.g. social work, housing). b p. 583). \200 Drug misuse is a community problem. Some aspects of harm reduction include consideration of reduction of morbidity to the community more gen- erally. Prescription of methadone may re duce criminality in a dependent indi- vidual, with consequent community bene \201 t. Equal ly, there is a responsibility with the prescriber to consider the potential for community h arm via leakage and accidental overdose when monitoring the prescription of any drug. 1 Prochaska JO and DiClemente CC (1986) Towards a comprehensive model of change. In Miller WR and Heather N (eds), Treating addictive behaviors: processes of change, pp. 3 \200\22327 . New York: Plenum Press. 15_Semple_Chap15.indd 544 12/7/2012 3:47:56 PM This page intentionally left blank CHAPTER 15 Substance misuse 546 Alcohol misuse In the UK, roughly 93% of men and 87% of women drink alcohol. Minimal alcoho l consumption can of course be pleasurable, socially enjoyable, and associated with health bene \201 ts (reduction in deaths from coronary artery disease). There is a tendency to vi ew most people as normal drinkers and a subset as vulnerable to the development of alcohol problems. In fact on a population level, increasing the overall alcohol consumption (e.g. b y reducing the real price of alcohol) tends to increase the total number of problem drinker s. Alcohol consumption in the community is roughly normally distributed with a long \200\230t ail \200\231 to the right. The distinction between normal and heavy drinking is arbitrary. On both a population and individual level, increased consumption is associated with increas ed risk of harm of all kinds. However, the fact that normal drinkers heavily outnumber heav y drink- ers means that, despite their lower rates of problems, greater numbers of alcohol- related problems occur in normal rather than heavy drinkers. This gives rise to the so-call ed \200\230prevention paradox \200\231 \200\224that to signi \201 cantly reduce overall a lcohol related morbidity we must look to reduce prob- lems in normal rather than heavy drin kers. This applies more to problems such as drink driving and drink-related trauma rather t han to medical com- plications of heavy use such as liver cirrhosis. The term \200\230alcoholic \200\231 is often used by patients themselves and is the prefer red term of Alcoholics Anonymous. It has unfortunately acquired a pejorative meaning to the general public, and images of the \200\230down and out \200\231 or \200\230skid row \200 \231 alcoholic, drinking strong drink from brown paper bags, have damaged this word \200 \231s use in clinical contexts. It is not used in DSM-IV or ICD-10 where the preference is to make the diagnosis of alcohol depend- ence or harmful use (abuse in DSM-IV). A history of alcohol use Alcohol has been used in all societies throughout recorded history , with documentary evidence of brewing and wine making as early as 3000 BC. The intoxicatin g effects of alcohol were most probably discovered inde- pendently in many cultures around the time of the evolution of agriculture, possibly on noting fermentation in fruit. Ancient peoples produced alco- holic beverages from a wide variety of materials including fruits, berries, honey, corn, barley, wheat, sugar cane, and potatoes. The use of alco- hol by indi viduals has been variously regarded, from complete tolerance through to outright prohibitio n. Alcohol has always had a place in the lifestyles and formal rituals of many peoples around the world. It was used as an intoxicant in religious rituals, as a celebration, as a gift, as a greeting, and to mark births and deaths. For almost as long as alcohol use is recorded there are recorded attempts at control on its use by the authorities. In AD 92 the Roman e mperor Domitian attempted to restrict wine production and its distribution and sale. Simila r restrictions were attempted at various times by other leaders, sometimes accompanied by m oral disapproval of drinking or drunkenness in particular. In medieval Britain, ale was a s taple part of the diet and was consumed in huge quantities, while drunkenness, particularly among 15_Semple_Chap15.indd 546 12/7/2012 3:47:56 PM ALCOHOL MISUSE 547 the clergy, was frowned upon by the Christian churches. Consumption of wine, however, conti nued to play a role in Christian worship. After initially preaching moderation, Mohammed la ter forbade the use of alcohol to fol- lowers of his religion, possibly as a way of differe ntiating his converts from the Christians around them. The process of natural fermentation of alcohol by yeasts can produce beverages of up to 13% proof: above this concentration the yeast dies. Stronger concentrations of alcohol are pro duced by the process of distilla- tion which was discovered in the Middle East in 1000 AD. Public consump- tion of distilled liquor became prevalent in the eighteenth century and the accompanying social problems together with the conservative attitudes of the emerging Prot estant clergy led to a developing moral disapproval of alcohol consumption. In the mid-eighteenth century, as part of a continuing military and trade dispute with Fran ce, the British government imposed heavy taxes on French wine imports and encouraged the di stillation of cheap domestic spirits \200\224in particular, gin. This change in the drinkin g practice in the gen- eral population from low- to high-strength alcohol produced signi \201 cant alcohol-related problems in the general public, immortalized in the litho- graphs of the \200\230gin palaces \200\231 by George Cruikshank. In an effort to control the pro blem the government passed laws to restrict the time and place at which alcohol could be so ld and began to levy increasing taxes on dis- tilled spirits. This had the positive effect of reducing consumption but the negative effect of introducing a government interest in con tinuing con- sumption. The late eighteenth-century writings of Benjamin Rush describe habit ual drunkenness as a \200\230disease of the mind \200\231. Eighteenth-century America saw the development of an increasingly widespread temperance mov ement (those signing a pledge \200\230TA \200\231 for total abstinence becoming known as t eetotallers). The temperance movement lobbied for a complete ban on alcohol consumption, an d succeeded in 1921 following the passing of the 18th amendment to the US Constitution whic h provided for prohibition. The period of 11 years until the repeal of prohibition in the 2 1st amendment did indeed see a reduction in social problems and mortality; however, its unp opularity, widespread \202 outing of the law, and the \202 ourishing of illegal activit y in gangsterism led to its repeal. Today, in most Western countries, alcohol use is widely tolerated and socially accepted. In terestingly, moral disapproval of drinking during preg- nancy and drinking while driving a motor vehicle has resulted in substantial decreases in these activities. Despite improvemen t in these limited areas, most Western countries have seen an increase in absolute consumpt ion and alcohol-related medical harm compounded by an increasing passion for drug misuse. 15_Semple_Chap15.indd 547 12/7/2012 3:47:56 PM CHAPTER 15 Substance misuse 548 Alcohol as a drug Preparations The active ingredient in alcoholic drinks is ethyl alcohol w hich makes up a variable percentage of the volume. The \202 avour of drinks comes from \200\230congeners \200\231 \200\224the additional organic substances derived from the brewi ng materials. Pattern of use Of all drugs, alcohol has the widest range of patterns of use, ranging from yearly light consumption to continuous consumption throughout the waking hour s. Drug actions The effects of alcohol on the CNS were traditionally described as being due to non-speci \201 c effects on neuronal cell wall \202 uidity and permeability. It is n ow believed that in addition to these general effects there are neurotransmitter-speci \201 c effects, including: enhancement of GABA-A transmission (anxiolytic effects), release of dopamine in the mesolimbic system (euphoriant and \200\230reward \200\231 effects), an d inhibition of NMDA-mediated glutaminergic transmission (amnesic effects). Ethyl alcohol i s oxidized by alcohol dehydrogenase (ADH) to acetaldehyde, which in turn is oxidized by ace taldehyde dehydrogenase (ALDH) to carbon dioxide and water. 98% of alcohol metabolism takes place in the liver. Approximately 1 unit (or 8g) of alcohol can be metabolized per hour. I llicitly brewed alcohol may contain methanol, which is broken down to formaldehyde, which h as marked toxic effects on the retina. Acute effects Alcohol is absorbed rapidly from mouth , stomach, and small intestine, and from a single consumption maximum blood levels are obta ined in 760min. Absorption is slowed by the presence of food in the stomach and is speeded up by taking effervescent drinks. Alcohol is hydrophilic and is widely distributed througho ut the body organs including the brain, placenta, lungs, and kidneys. Blood alcohol concent ration (BAC) is consistent throughout the body with the exception of fat and can be estimat ed from breath samples. In normal drinkers BAC correlates with the subjective and the obser vable CNS effects of alcohol. Heavy drinkers may have a high BAC with limited outward signs of intoxication due to the development of tolerance. Because of their different body fat d istribution, women will have a higher BAC than men following the same oral intake. Initial symptoms of alcohol intoxication are subjective elevation of mood, increased socialization, and disinhibition. Continuing consumption, intended to prolong these effects, can lead to lability of mood, impaired judgment, aggressiveness, slurred speech, unsteady gait, and ata xia. Societal factors The prevalence of alcohol-related harm increases with the mean popula tion consumption. This mean consumption is increased by increased availability of alcohol, increased societal tolerance of drinking, decreased restrictions on the sale of alcohol, an d a decreased \200\230real price \200\231 of alcohol. Price is the most in \202 uential f actor in demand, the real price of a pint of beer or bottle of whisky having dropped consid erably since the war. Where societies forbid all alcohol consumption (e.g. prohibition Amer ica, Islamic counties), there is a decrease in alcohol-related problems but an increase in the level of personality abnormality in those who continue to drink. 15_Semple_Chap15.indd 548 12/7/2012 3:47:56 PM ALCOHOL AS A DRUG 549 Risk factors Heavy drinking is more common in men, in lower socio- economic groups, in thos e with lower educational levels, and in the young. Some professions are also associated wit h heavy drinking and drink-related harm. These include drinks industry workers (easy availa bility and effect of heavy drinkers seeking out jobs here); traveling salesmen (boredom, pe riods away from home, acceptance of drinking on the job); doctors (stress, freedom from dir ect supervision, reluctance to seek help with incipient problems). Genetics First-degree re latives of alcoholics have double the risk of alcohol problems themselves. Signi \201 cant ly higher rates in identical compared with fraternal twins (although not 100% concordance). Children of alcoholics have increased risk of development of alcohol problems themselves e ven when adopted into families without alcohol problems. A metabolically relatively inactiv e form of ALDH is common in Southeast Asian people, leading to accumulation of acetaldehyde and an unpleasant \200\230 \202 ushing \200\231 reaction in affected individuals who tak e alcohol. This may account for the signi \201 cantly lower rate of alcohol problems found in affected individuals. No causative genes for alcoholism have been identi \201 ed and i t is expected that it will show polygenic inheritance. Problem drinkers contain a signi \201 cant subgroup of individuals with dissocial personality traits which predisposes to al coholism, and is itself heritable. Medical complications Acute toxicity occurs at levels ov er 300mg% (see b p. 566), with clouding of consciousness and coma, risk of aspiration, hypo glycaemia, and acute renal failure. Associated with a wide range of chronic medical problem s (b p. 574). Psychiatric complications Harmful use and dependent use (b p. 566) distinguis hed by the presence of withdrawals on abstinence; withdrawals may be complicated by seizure s and development of an acute confusional state \200\224delirium tremens (b p. 558); acute alcohol-induced amnesia; alcoholic hallucinosis (b p. 568); alcohol-induced delusional diso rder (b p. 568); Wernicke \200\223Korsakoff syndrome (b p. 572); pathological jealousy (b p . 569); alcohol-related cognitive impairment and alcoholic dementia (b p. 568); alcohol mis use is also associated with development of, or exacerbation of, anxiety/depressive symptoms and with deliberate self-harm and suicidal behavior. Interventions Advice and \200\230bri ef interventions \200\231 regarding safer drinking patterns in those with \200\230at risk \200\231 or harmful use (b p. 566); strategies towards encouraging and maintaining abstinen ce in those with dependency and those with established medical or psychiatric damage; medic ally managed detoxi \201 cation (b p. 560); psychological and pharmacological support of a bstinence or changed drinking pattern (b pp. 562 \200\2235). 15_Semple_Chap15.indd 549 12/7/2012 3:47:57 PM CHAPTER 15 Substance misuse 550 Screening for alcohol problems Diseases related to alcohol abuse are common, signi \201 ca nt, and amenable to improvement by early detection and intervention. Screening is there- fo re indicated. There are low rates of detection in primary care and hos- pital settings, whi ch may be improved by increased vigilance, increased awareness of alcohol problems, awarene ss of routes of referral, asking routine alcohol-screening questions (e.g. CAGE \200\224see Box 15.1), paying special attention to at-risk groups. Many patients give reasonably accur ate drinking histories if asked, although some may underestimate consump- tion. A combinati on of clinical history, screening measure, and a biomarker is the optimal approach to detec tion. Disorders suggesting underlying alcohol abuse Hepatitis; cryptogenic (i.e. medically unexplained) cirrhosis; seizures \200\224particularly late onset; gastritis; anemia; unexpl ained raised MCV or deranged LFTs; cardiomyopathy; accidents, particularly repeated and poo rly explained; TB; head injury; hypertension persisting despite apparently adequate treatme nt; treatment resistance in other psychiatric conditions; impotence in men. Breath testing Blood alcohol concentration (BAC) measures recent alcohol consumption, in mg alcohol per 10 0mL blood (mg%). Correlates well with breath alcohol measured by breathalyzer (see Table 15 .1). Useful in assessing recent drinking (e.g. in supervised detox regimes) and as an objec tive measure of intoxication (e.g. in A&E). Discrepancy between high BAC and lack of appare nt intoxication suggests tolerance. This measurement is dependent on adequate technique, an d reasonable co-operation from the patient. Blood tests Elevated red cell mean corpuscular volume (MCV), gamma glutamyl transferase (G-GT), and carbohydrate-de \201 cient transferri n (CDT) are markers for excess alcohol consumption. They are best used to monitor consumpti on in patients at follow-up. Not sensitive/speci \201 c enough for routine screening purpo ses. \200 MCV months due to 120-day lifespan of RBC. False positive in B12 and folate de \201 ciency . Sensitivity 20 \200\22350%, speci \201 city 55 \200\223100%. Remains raised for 3 \200\223 6 G \200 GT Sensitivity 20 \200\22390%, speci \201 city 55 \200\223100%. Raised for 2 \200\2233wks. Other LFTs are less speci \201 c for alcoholic-related liver damage. False positive in li ver diseases of other cause, obesity, diabetes, smoking, and medication (e.g. anticonvulsan ts), and may remain raised in chronic alcoholic liver disease despite abstinence. CDT Sensi tivity 70%, speci \201 city 95%. Increased levels in response to heavy drinking (7 \200 \22310 days), 2 \200\2233wks to return to normal, can be used to monitor relapse. More expe nsive than G-GT and not available in all areas. Urinary tests Urinary ethyl glucoronide (an alcohol metabolite) has been proposed as a meas ure of alcohol intake, being sensitive to ingestion of 1 or 2 drinks, remaining elevated fo r several days. It has still to be used routinely, though has been used in forensic setting s. 15_Semple_Chap15.indd 550 12/7/2012 3:47:57 PM SCREENING FOR ALCOHOL PROBLEMS 551 Hair testing Testing of hair for ethyl glucoronide or fatty acid ethyl esters has been prop osed as a method for detecting alcohol use over prior months, though requires further resea rch and validation. Box 15.1 CAGE questionnaire A brief screening questionnaire for identi \201 cation of at-risk drinking: C: Have you ev er felt you should Cut back on your drinking? A: Has anyone ever Annoyed you by criticizing your drinking? G: Have you ever felt Guilty about your drinking? E: Have you ever had a dr ink early in the morning as an Eye-opener? More than two positive responses suggests possib le at-risk drinking and should prompt further assessment. Note: the \200\230Cage +2 \200 \231 adds two additional questions: 1. 2. What is the most alcohol you have drunk in a single day? What is the most alcohol you have drunk in a single week? Table 15.1 Breath and blood alcohol levels Breath alcohol reading (mcg%) BAC (mg%) 0.35 80 0.52 120 0.70 160 0.87 200 1.05 240 1.40 320 1.75 400 A breathalyzer allows an objective measurement of the breath alcohol and hence an approxima tion of the BAC. Breath alcohol reading should form part of the routine assessment of a pat ient presenting with alcohol problems and of patients in follow-up (e.g. supervised detox), rather than being prompted by suspicion of inaccuracy of oral report. 15_Semple_Chap15.indd 551 12/7/2012 3:47:57 PM CHAPTER 15 Substance misuse 552