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CONCURRENT PSYCHIATRIC & SUBSTANCE USE DISORDERS. PHM 462 November 11, 2004. Beth Sproule, Pharm.D. Learning Objectives. At the completion of this class, students will be able to: Consider the clinical implications of concurrent psychiatric and substance use disorders.
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CONCURRENT PSYCHIATRIC & SUBSTANCE USE DISORDERS PHM 462 November 11, 2004 Beth Sproule, Pharm.D.
Learning Objectives At the completion of this class, students will be able to: • Consider the clinical implications of concurrent psychiatric and substance use disorders. • Identify and describe the unique drug-related problems encountered by patients with concurrent psychiatric and substance use disorders.
Case Study Harry is a 35 year old man with a 10 year history of schizophrenia admitted for acute decompensation. He reported having low energy and the onset of hearing voices 2 weeks prior to admission. A long-time cocaine user, he reported increasing his use of cocaine on the weekends for the last few weeks.
Case Study • The psychiatric diagnosis is clear. What is the likely substance use disorder? • How common do you think this is?
Epidemiology Regier et.al. JAMA 1990;264(19):2511-2518.
Epidemiology Regier et.al. JAMA 1990;264(19):2511-2518.
Case Study The onset of increased cocaine use coincided with hearing the voices – what may that suggest with respect to the relationship between the disorders? How could the cocaine have affected the psychotic illness?
Possible Relationships The psychiatric disorder is induced by the substance use disorder. Examples: • psychosis from cocaine intoxication • anxiety from benzodiazepine withdrawal • anxiety from high doses of caffeine • Mania from amphetamine intoxication
DSM-IV Substance-Induced Persisting Disorders • Substance-Induced Persisting Dementia • alcohol, inhalants, sedative/hypnotics • Substance-Induced Persisting Amnestic Disorder • alcohol, sedative/hypnotics • Hallucinogen Persisting Perception Disorder • AKA “Flashbacks”
DSM-IVSubstance-Induced Disorders Evidence from history or examination that suggests a substance-induced disorder: • symptoms developed during or within 1 month of substance intoxication or withdrawal • presence of features atypical of psychiatric disorder (e.g., first manic episode after age 45) • substance-specific effects consistent with the disturbance
DSM-IVSubstance-Induced Disorders Evidence that suggests that the disturbance is better accounted for by non-substance-induced disorder: • symptoms precede the onset of substance use • symptoms persist for a period of time (e.g., about a month) after the cessation of acute withdrawal or severe intoxication • symptoms are in excess of what would be expected • family history
Possible Relationships The substance use disorder is causally dependent on the psychiatric disorder (i.e., functionally linked, “self-medication”). Example: • Panic disorder leads to dependence on benzodiazepines
Possible Relationships The psychiatric disorder and the substance use disorder have common risk factors. Example: • Personality disorders leading to substance abuse
Possible Relationships The psychiatric disorder and the substance use disorder are independent of each other. Example: • a simple phobia in an alcohol abuser
Case Study Albert is a 45 year old single male, employed in the service industry, although his job is in jeopardy due to absenteeism. His chief complaints are of anxiety, depression, insomnia, and stress related to his girlfriend threatening to leave. He describes symptoms of fatigue, difficulty concentrating and weight loss. Upon questioning it is determined that he has been drinking heavily (1.5 litres of wine daily) for 20 years. He says he was treated with benzodiazepines in the past for depression. He has had a brief inpatient stay in a psychiatric unit for ‘stress’. Albert refused to undergo acute alcohol withdrawal treatment. Instead a program of gradual withdrawal was agreed upon, with a target of 10% reduction weekly. Three weeks later Albert is still drinking the same amount. He says that although he wants to reduce his drinking he has been unable to due to his persistent feelings of low mood and anxiety.
Case Study • What is the likely substance use disorder? • What is the likely psychiatric disorder?
Tolerance Withdrawal More or longer than intended Unable to cut down or control use Great deal of time spent around substance use Important activities given up Use continues despite link to physical or psychological problem DSM-IV Substance Dependence 3 criteria leading to significant impairment/distress:
DSM-IV Major Depressive Episode and represents a change 5 symptoms for 2 weeks from previous functioning: • depressed mood • loss of interest/pleasure • appetite • sleep • psychomotor agitation • fatigue must include 1 of these • worthlessness • concentration • thoughts of death
Case Study • Does this patient require pharmacotherapy? • What DRPs would you anticipate in this patient?
Pharmacotherapy for Depression & Alcohol Dependence • TCAs - conflicting evidence whether both depressive symptoms and drinking respond • SSRIs • Fluoxetine – shown to reduce depressive symptoms and alcohol consumption • Sertraline – reduced drinking in alcohol-dependent patients without lifetime depression; reduced drinking in depressed, adolescent alcoholics • Combinations – naltrexone & SSRI
Drug-Related Problems in a Comorbid Population • Drug interactions • Medication compliance • Abuse/addiction potential of psychotherapeutic agent
Drug Interactions Combining prescribed psychotherapeutic drugs with: • Alcohol • Street drugs • Nicotine • OTC psychotropic drugs
Compliance Weiss RD et.al., Medication compliance among patients with bipolar disorder and substance use disorder. J Clin Psychiatry 1998;59:172-174. • n=44, 55% female, age 37 9 years • > 2/3 level of compliance: • lithium 67%, VA 73%, CBZ 67%, SSRIs 85% • Reasons for non-compliance: • side-effects, no need, wanted to use drugs/alcohol, hassle, forgot • may take higher doses than prescribed
Abuse of Psychiatric Medications • anticholinergic agents • benzodiazepines
Question Antipsychotic and antidepressant medications are not usually subject to abuse because: a) they are more strictly controlled than other drugs b)in general, they do not produce euphoria and may have unpleasant side-effects c) they are generally not prescribed on a long-term basis d) they are only available orally
Question Antipsychotic and antidepressant medications are not usually subject to abuse because: a) they are more strictly controlled than other drugs b) in general, they do not produce euphoria and may have unpleasant side-effects c) they are generally not prescribed on a long-term basis d) they are only available orally
Anticholinergic Agents Examples: • benztropine (Cogentin®) • procyclidine (Kemadrin®) • trihexyphenidyl (Artane®) • dimenhydrinate (Gravol®) • tricyclic antidepressants • abuse potential limited by relative mildness of euphoric effect and unpleasant side-effects
Benzodiazepines • Relatively low abuse liability compared to barbiturates, alcohol, opioids, stimulants • low inherent harmfulness and ease of availability increase potential for abuse • low dose versus high dose abuse or dependence