Noeline Latt

Thiamine in the treatment of Wernicke encephalopathy in patients with alcohol use disorders

Wernicke encephalopathy is an acute, reversible neuropsychiatric emergency due to thiamine deficiency. Urgent and adequate thiamine replacement is necessary to avoid death or progression to Korsakoff syndrome with largely irreversible brain damage. Wernicke Korsakoff syndrome refers to a condition where features of Wernicke encephalopathy are mixed with those of Korsakoff syndrome. Although thiamine is the cornerstone of treatment of Wernicke encephalopathy, there are no universally accepted guidelines with regard to its optimal dose, mode of administration, frequency of administration or duration of treatment. Currently, different dose recommendations are being made. We present recommendations for the assessment and treatment of Wernicke encephalopathy based on literature review and our clinical experience.

Epidemiology of alcoholic liver disease

Although mortality from alcoholic liver disease has declined in some Western countries in recent years, elsewhere it is increasing and overall it remains a major health problem. Deaths are predominantly seen in patients with alcoholic hepatitis or cirrhosis, and when they occur in patients with fatty liver are usually unrelated to liver disease. Progression to cirrhosis is correlated with the severity of fatty liver and particularly with the presence of alcoholic hepatitis. Mortality from cirrhosis is strongly correlated with per capita alcohol consumption. The decline in cirrhosis mortality rates seen recently is related in part to decreases in per capita consumption, but probably also to the growth of self-help organizations which facilitate abstinence from alcohol. Recent studies suggest there is not an invariable dose-response relationship between alcohol intake and the severity of liver disease and that alcohol has a permissive effect which allows other aetiological factors to operate. Factors that influence susceptibility to alcoholic liver disease include gender (women develop alcoholic cirrhosis more readily than men), concomitant hepatitis C infection and possibly hepatitis B infection. It is uncertain whether HLA status or immune mechanisms are implicated. The systematic use of screening tests for hazardous consumption combined with early intervention therapies offers a good prospect of reducing morbidity and mortality from alcoholic liver disease.

Hepatitis C in injecting drug-using women during and after pregnancy.

Background : A high proportion of female injecting drug users (IDU) have evidence of hepatitis C virus (HCV) infection. We undertook a prospective study of patients attending a clinic for pregnant IDU to determine the impact of pregnancy on the course of HCV infection and whether pregnancy is affected by HCV infection.

Alcohol and substance use by patients with psychosis presenting to an emergency department: changing patterns.

Objectives: The aim of this study was to determine the incidence of alcohol and other substance use in patients presenting to an emergency department with acute psychiatric illnesses and to clarify the role of urine drug screens. Method: This was an unblinded prospective (observational) cohort study incorporating retrospective review of patient medical records, history of alcohol and substance use, results of urine drug screens and blood alcohol concentrations. Results: Of 196 acute psychotic patients, 104 were diagnosed with schizophrenia and 92 with “other psychosis”. Results of urine drug screens were consistent with self-reported use of substances and only identified an additional 5% of substance users. Cannabis was the commonest illicit substance used by both groups of patients, followed by psychostimulants, mainly amphetamines. Younger males were more likely to use psychostimulants and to present with violence. Conclusions: Patients with co-existing mental health problems and substance use present a major problem for our emergency departments. Cannabis was the most common substance used. Youth, male gender and psychostimulant use are associated with violent presentations. A comprehensive history of alcohol and substance use is important to implement appropriate dual diagnosis treatment. Urine drug screening is recommended for patients who do not admit to substance use.

Diagnosis and Classification of Substance Use Disorders

Substance use and misuse exist at a hierarchy of disorders. Some forms of substance use, e.g., alcohol, are non-harmful or at least very low risk, while others, such as the prescription of benzodiazepines, are medically appropriate in certain circumstances. However, alcohol, certain prescribed (and pharmacy) medications, and illicit drugs have an inherent capacity to cause dependence (addiction) and a range of physical, psychological, and social harms. A hierarchy of diagnoses exists to describe various levels of substance use disorders. Repetitive substance use, which confers the risk of harmful consequences because of its known effects, is termed “hazardous use” or “risky use”. These terms are used widely by many national authorities and medical and health care organizations. “Substance abuse” is a Diagnostic and Statistical Manual of Mental Disorders, 4th Edition term denoting a maladaptive and repetitive pattern of substance use that causes essentially social and personal problems. “Harmful use” is an International Statistical Classification of Diseases and Related Health Problems, 10th Revision term denoting repetitive substance use that actually causes physical or psychiatric harm. The existence of social problems is in itself insufficient for the diagnosis of harmful use. At the top of the hierarchy in both the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition and the International Statistical Classification of Diseases and Related Health Problems, 10th Revision is a substance dependence syndrome defined as a psychobiological syndrome that comprises impaired control over substance use, tolerance, and withdrawal symptoms and is characterized by continued use of the substance despite harmful consequences. The term “dependence syndrome” has replaced older terms such as “alcoholism” and “addiction”, although there is a move presently to reinstate addiction as a diagnostic term. Underlying the dependence syndrome is a set of profound and enduring neurobiological changes in the reward, stress, and control systems in the midbrain and lower forebrain. I liken the dependence syndrome to a powerful internal “driving force” that drives the person’s use of that substance in a self-perpetuating way. Separate from these diagnoses, which refer to repeated substance use and are the “core” substance use disorders, are the numerous complications, including substance-induced mood disorders, anxiety disorders, psychotic disorders, and many neuropsychiatric impairments and physical diseases. Diagnosis is based on a set of specific diagnostic criteria that reflect the particular pattern of substance use and the psycho-physiological attributes and mental and other consequences of the condition. Clinical diagnosis of these disorders is based on clinical knowledge and training, and there are several diagnostic interview schedules, together with screening and assessment instruments, that contribute to the diagnosis. Schedules quantifying various forms of substance use also are available; laboratory tests reflecting the physiological effects of alcohol or that detect the presence of a drug or its metabolites also contribute to the diagnosis but do not specifically indicate which one. Cerebral imaging techniques are increasingly powerful demonstrations of the physiological processes of dependence but are not yet at the stage where they can contribute directly to making a diagnosis. The same applies to various genetic and other physiological tests. However, these may well have clinical diagnostic value with their further development in the years ahead.

Specific clinical situations

One of the most common sources of pain is postoperative pain. A large amount of the evidence presented so far in this document is based on studies of pain relief in the postoperative setting. However, many of the management principles derived from these studies can be applied to the management of acute pain in general, as outlined in this and other sections that follow.

L’obiettivo della Medicina delle dipendenze

L’utilizzo di sostanze psicoattive ha da millenni un ruolo integrante nella storia dell’uomo, ma con differenze notevoli sia per quanto riguarda la natura delle sostanze usate sia per i motivi del loro impiego. Esistono in natura migliaia di sostanze e queste sono state sostituite, negli ultimi 200 anni, da composti sintetici, prodotti per scopi medicinali o s empli cemente edonistici. In tutto il mondo, il 48% della popolazione adulta totale (ca. 2 miliardi di persone) consuma alcolici almeno occasionalmente; il 33% (ca. 1,3 miliardi di persone) fuma tabacco, principalmente in forma di sigaretta, e il 5% (ca. 200 milioni di persone) usa sostanze illecite. Sempre piu il quadro dei comportamenti associati all’utilizzo di sostanze include il consumo di sostanze multiple, spesso con effetti farmacologici diversi.

Situazioni cliniche specifiche

L’esperienza dell’insonnia e soggettiva: chi la vive presenta difficolta ad addormentarsi, frequenti e prolungati risvegli durante la notte e risveglio al mattino presto; cio e molto comune fra i pazienti che abusano di sostanze e che sono in astinenza. In effetti, circa il 60% dei pazienti dipendenti da alcol soffre di insonnia prima di smettere di bere e, con ogni probabilita, e ricorso all’alcol come automedicazione per cercare di dormire; anche i soggetti dipendenti da oppioidi con disturbi del sonno utilizzano benzodiazepine o alcolici come aiuto per addormentarsi. La comorbidita fra abuso di sostanze e depressione e frequente, e gli effetti di entrambe le condizioni sul sonno si sommano.

Valutazione e diagnosi: principi generali

La valutazione e il primo passo nella diagnosi e nella gestione di pazienti con problemi connessi all’alcol e altre droghe. La valutazione permette lo sviluppo di una relazione terapeutica e consente al medico di dimostrare preoccupazione per il paziente e per i problemi che deve affrontare e quindi e essa stessa parte del processo terapeutico.

Farmaci sedativo-ipnotici

I farmaci sedativo-ipnotici inducono una depressione del SNC agendo sui recettori del sistema GABA-A, il principale sistema inibitore cerebrale. Numerosi sedativo-ipnotici sono disponibili su prescrizione o, in alcuni paesi, possono essere acquistati in farmacia o (illecitamente) da spacciatori o su internet.