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  1. PSY344 – Week 1
  2.   Schizophrenia literally means ‘Fragmented Mind’ or ‘split-mind’ due to the inability to differentiate fantasy and reality.  Schizophrenia is considered one of the mot complex, chronic and challening psychiatric disorders affecting how a person thinks, feels, behaves and severely distorts perception.  It represents a heterogenous syndrome of disorganized thoughts, delusions, hallucinations and impaired psychosocial functioning. Schizophrenia
  3.   While many factors have been associated with developing schizophrenia.  These include genetics, early environment, neurobiology and psychological and social processes.  An exact cause of the disease still cannot be accounted for. Etiology
  4.  Etiology
  5.   Viral Infections and Immune Disorders:  Schizophrenia may be triggered by environmental events, such as viral infections or immune disorders.  For instance, babies whose mothers get the flu while they are pregnant are at higher risk of developing schizophrenia later in life. People who are hospitalized for severe infections are also at higher risk.  Genetics:  Scientists recognize that the disorder tends to run in families and that a person inherits a tendency to develop the disease. Similar to some other genetically-related illnesses, schizophrenia may appear when the body undergoes hormonal and physical changes.  The risk of developing schizophrenia is increases to approximately 10% if a first-degree relative has the illness and to 3% if a second-degree relative has the illness. If both parents have schizophrenia, the risk of producing a schizophrenic offspring increases to approx 40%. 5 Etiology
  6.   The prevalence of schizophrenia ranges from 0.6% to 1.9%, with an average of approximately 1%  Schizophrenia most commonly has its onset in late adolescence or early adulthood and rarely occurs before adolescence or after the age of 40 years. The peak ages of onset are 20–38 years for males and 26– 32 years for females.  Slightly more men are diagnosed with schizophrenia than women and tend to be diagnosed later in life than men. Epidemiology
  7.  Epidemiology
  8.   Schizophrenia  Schizotypal (Personality) Disorder  Brief Psychotic Disorder  Schizophreniform Disorder  Schizoaffective Disorder  Substance Induced or Due To Another Medical Condition Types According to DSM
  9.   Schizophrenia breaks down into 3 categories of symptoms.  These are as follows:  Positive Symptoms  Negative Symptoms  Cognitive Deficits Symptom Types
  10.   Positive Symptoms refer to overt symptoms that shouldn’t be present. These include;  Hallucinations  Delusions  Disorganized Thoughts Positive Symptoms
  11.   Negative symptoms refer to a lack of characteristics that should be present. These can include;  Reduced speech even when encouraged to interact (alogia)  Lack of emotional and facial expressions (affective flattening)  Diminished ability to begin and sustain activities (avolition)  Decreased ability to find pleasure in everyday activities (anhedonia)  Social withdrawal (asocial) Negative Symptoms
  12.   Refers to difficulties with following aspects of cognition that can make it hard to live a normal life or sustain a job / living. These include deficiencies in;  Memory  Attention Cognitive Deficits
  13.   Delusions: False beliefs that are not based on reality.  Hallucinations: Involving seeing or hearing things that don’t exist.  Disorganized Speech and Thinking: Effective communication can be impaired and answers to questions may be partially or completely unrelated.  Catatonia: Purposeless abnormal motor activity or aggressive behaviour. Positive Symptoms Examples
  14.   Flat Effect: Reduced expression of emotions facial expression or voice tone.  Alogia: Reduced speech.  Avolition: Inability to begin and sustain activities.  Anhedonia: Inability to experience pleasure.  Asociality: Withdrawal from social contacts.  Reluctance to perform everyday tasks. Negative Symptoms Examples
  15.   Any visible cognitive impairment can be considered as a cognitive symptom category, the most commonly observed are;  Poor Execution Functioning: Inability to understand information to make decisions.  Poor Working Memory: Inability to use information immediately after learning. Cognitive Symptoms Examples
  16.  The Brain Associated with Schizophrenia
  17.   Dopamine Hypothesis:  Numerous Positron Emission Tomography (PET) studies have shown dopaminergic hyperactivity in the nucleus accumbens and dopaminergic hypofunction in the frontal temporal regions.  PET studies using D2-specific ligands provide data suggesting increased densities of D2 receptors in the nucleus accumbens.  PET studies assessing D1 function suggest that subpopulations of schizophrenics may have decreased densities of D1 receptors in the prefrontal cortex.  Thus positive symptoms are thought to result from overactivity in the mesolimbic dopaminergic pathway activating D2 receptors whereas negative symptoms may result from a decreased activity in the mesocortical dopaminergic pathway where D1 receptors predominate. Pathophysiology
  18.  Pathophysiology
  19.  Pathophysiology
  20.  Pathophysiology
  21.   Glutamate Hypothesis:  NMDA receptor hypofunction is thought to reduce the level of activity in mesocortical dopaminergic neurons. This would result in a decrease in dopamine release in the prefrontal cortex and thus give rise to negative symptoms of schizophrenia.  On the other hand, NMDA receptor hypofunction is thought to enhance activity in the mesolimbic dopaminergic pathway, perhaps because in this pathway the important NMDA receptors are those located on GABA interneurons.  Thus NMDA receptor hypofunction would result in reduced GABA inhibition (disinhibition) of mesolimbic dopaminergic neurons and thus give rise to enhanced dopamine release in limbic areas such as the nucleus accumbens. Pathophysiology
  22.  Pathophysiology
  23.   5-HT (Hydroxytryptamine (Serotonin)) Hypothesis:  Serotoninergic receptors are present on dopaminergic axons and it is known that stimulation of these receptors will decrease DA release in prefrontal cortex.  Patients with schizophrenia with abnormal brain scans have higher whole blood 5-HT concentrations and these concentrations are correlated with increased ventricular size.  Atypical antipsychotics with potent 5-HT2 receptor antagonist effects reverse worsening of symptomatology induced by 5-HT agonists in patients with schizophrenia. Pathophysiology
  24.   Depression:  Depression afflicts approximately half of schizophrenic patients. Sadly, it is not always recognized or treated. It can significantly add to the suffering of the person. Additionally, comorbid depression increases the risk of suicide in schizophrenic.  Anxiety:  Many individuals with schizophrenia also have an anxiety disorder, such as social anxiety disorder, PTSD, generalized anxiety disorder, OCD or panic disorder. In fact, research suggests between 30% and 85% of people with schizophrenia have had an anxiety disorder at some point in time.  Suicide:  Suicide is one of the primary causes of death for individuals with schizophrenia. There are several factors which contribute to suicide risk in schizophrenia which include psychotic symptoms, such as voices telling the person to kill himself, substance abuse, recent diagnosis of schizophrenia and comorbid depression Complications
  25.   Substance Abuse and Smoking:  Substance abuse is a form of self-medication for many people with psychiatric disorders. Unfortunately, when patients use substances such as alcohol or street drugs it can make their symptoms worse. They are also less likely to continue taking their medications when they abuse substances.  Violence:  While the media often depicts schizophrenic patients as violent, they are not necessarily more prone to violence than the general population. That being said, some factors can increase the risk of violent behavior in individuals with schizophrenia, such as delusions or command hallucinations, a history or violent acts or using alcohol or drugs.  Self-injury:  Self-injury, especially bizarre types of self-mutilation, is not uncommon with schizophrenia. Hallucinations and delusions can cause them to harm themselves in ways which can be very serious, such as attempting to remove a finger or other body part. Complications
  26.   Diagnostic Criteria of Schizophrenia:  Includes the criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM-V-TR), published by the American Psychiatric Association.  Medical History:  A thorough medical history is the first step in the diagnosis of schizophrenia. This may be done to find other problems that could be causing symptoms and to check for any related complications.  Blood Tests and Imaging:  A Complete Blood Count (CBC) test is helpful to monitor general health and rule out other conditions that may have been responsible for the symptoms. A blood test can provide accurate information about the involvement of recreational drugs. In some cases, certain imaging techniques such as Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) scan may aid in the diagnosis. Diagnosis
  27.   A doctor or mental health professional checks mental status by observing appearance, demeanor and asking about thoughts, moods and awareness. A person may be diagnosed if they have at least 2 of the following symptoms usually over a month:  Delusions  Hallucinations  Disorganised behaviour  Disorganised speech and thought processes  Catatonic behaviour, presenting as strong daze or hyperactivity  Negative symptoms, impaired normal function Psychiatric Evaluation
  28.   There is no known cure for Schizophrenia. Fortunately, there are effective treatments that can reduce symptoms, decrease the likelihood that new episodes of psychosis will occur, shorten the duration of psychotic episodes, and in general, offer the majority of people the possibility of living more productive and satisfying lives.  With the proper medications and supportive counseling, the ability of schizophrenic persons to live and function relatively well in society is excellent. Prognosis
  29.   Hospitalization:  During crisis periods or times of severe symptoms, hospitalization may be necessary to ensure safety, proper nutrition, adequate sleep and basic hygiene.  Psychosocial Interventions:  Individual Therapy: Psychotherapy may help to normalize thought patterns. Also, learning to cope with stress and identify early warning signs of relapse can help people to manage their illness.  Social Skills Training: This focuses on improving communication, social interactions and improving the ability to participate in daily activities.  Family Therapy: This provides support and education to patient families.  Vocational Rehabilitation and Supported Employment: This focuses on helping people with schizophrenia prepare for, find and keep jobs. Management Hospitalization
  30.   Electroconvulsive Therapy:  For adults with schizophrenia who do not respond to drug therapy, electroconvulsive therapy (ECT) may be considered. ECT may be helpful for someone who also has depression.  The indications for ECT in schizophrenia are:  Catatonic stupor & uncontrolled catatonic excitement.  Acute exacerbations not controlled with drugs.  Risk of suicide, homicide or danger of physical assault.  Cognitive Behavioural Therapy:  CBT aims to help to identify the thinking patterns that are causing to have unwanted feelings & behavior and learn to replace this thinking with more realistic and useful thoughts.  Most people require between 8 and 20 sessions of CBT over the space of 6 to 12 months. CBT sessions usually last for about an hour. Management Hospitalization
  31.   Clinical Management:  The APA guidelines treatment recommendations for patient with schizophrenia divide the treatment into 3 phases:  Acute Phase (Initial Presentation) 4 to 8 weeks: Defined by acute psychotic episode.  Stabilization Phase (Early symptom remission) as long as 3 months: Constitutes a time – limited transition to continuing treatment.  Stable Phase (Maintenance treatment): Involves stable treatment. Management Hospitalization
  32.  APA Guidelines and Treatment Goals for Schizophrenia
  33.   Typical or Classical or 1st Generation Antipsychotics:  A. Phenoziazins:  1. With aliphatic amine side chain:  Chlorpromazine, Triflupromazine  2. With Piperidine side chain:  Thioridazine  3. With Piperazine side chain:  Trifluoperazine, Fluphenazine  B. Butyrophenones:  Haloperidol, Trifluperidol, Penfluridol  C. Thiohaxanes:  Flupenthixol, Thiothixene  D. Other heterocyclics:  Pimozide, Loxapine Antipsychotics, Neuroleptic and Major Tranquilizers
  34.   Clozapine  Olanzapine  Quetiapine  Aripiprazole  Risperidone  Amisulpride  Ziprasidone Atypical or Novel or 2nd Generation Antipsychotics
  35.  Treatment Algorithm
  36.   Stage 1:  Treatment only applies only to those patients experiencing their first episode of schizophrenia.  Stage 2 and 3:  Recommends either First Generation Antipsychotics or Second Generation Antipsychotics, with the exception of clozapine. Because of safety concerns and the need for white blood cell (WBC) monitoring, it is recommended that patients be tried on one newer Second Generation Antipsychotics and one other Second Generation Antipsychotics or First Generation Antipsychotics as monotherapy before proceeding to a trial of clozapine.  Clozapine has superior efficacy in decreasing suicidal behavior, and it should also be considered as a higher treatment option in the suicidal patient (stage 3). Clozapine can also be considered earlier in treatment in patients with a history of violence or comorbid substance abuse. Treatment Algorithm
  37.   Stage 4, 5 and 6:  Includes clozapine and augmentation with either a FGA, SGA, or electroconvulsive therapy (ECT). Combination treatment at this stage is supported by limited controlled and equivocal evidence.  In general, patients who experience poor improvement with clozapine do not respond well with other antipsychotic monotherapies (Stage 5).  Stage 6 combination pharmacotherapy interventions should be implemented with time limited, careful evaluation of a patient’s symptom response and discontinuation of the combination if improvement does not occur.  If partial or poor adherence contributes to inadequate clinical improvement, then long-acting or depot injectable antipsychotics should be considered.  Risperidone microspheres is the only available long-acting injectable SGA, and long-acting FGAs include fluphenazine decanoate and haloperidol decanoate. Treatment Algorithm
  38.   All anti psychotics (except clozapine-like atypical) have potent dopamine D2 receptor blocking action.  Antipsychotic action of typical neuroleptic is believed to produced by competitive blockade of postsynaptic D2 receptors in mesolimbic system.  Initially D2 presynaptic receptors are also blocked, which increases, synthesis and release of dopamine, so its metabolites like HVA and DOPAC level is increase in blood and urine.  But on prolonged use, there is a feedback inhibition of DA release, due to increased DA concentration in synaptic cleft, which result in decrease turnover and release.  Atypical neuroleptics drug also block D2 receptor in nigrostriatal pathway and explain the unwanted exrapyramidal side effects (EPS). Typical Antipsychotics
  39.   Blockage of D2 receptor in CTZ is responsible for antiemetic effects.  Neuroleptics consistently increase prolactin release by blocking the inhibitory action of DA on pituitary lactotropes. This may result in galactorrhoea and gynaecomastia  Typical antipsychotic drugs Have varying degree of other receptor blocking activity: Clorpromazine: α1 = 5-HT2 > D2 = D4 > D1 > M1 Thioridazine: α1 > D2 > M1 = 5-HT2 > D1 Haloperidole: D2 > α1 > D4 > 5-HT2 > D1 Primozide: D2 > 5-HT2 > D4  These drugs produce hypotension due to high α blocking property.  Chlorpromazine potent a local anaesthetic as procaine but is not used for this purpose because irritant action. Typical Antipsychotics
  40.   These newer atypical antipsychotic medications are general prefered because they pose a lower risk of serious adverse effects than do typical antipsychotics.  These drugs have a moderate to high D2 antagonism and high 5-HT2A antagonism. Clozapine have low D2 antagonism and high 5-HT2A antagonism.  Exception of aripiprazole, all atypical antipsychotics have higher 5-HT2A antagonism than D2 receptor antagonism.  Blockade of 5-HT2A receptor leads to release of dopamine in prefrontal cortex responsible for decrease in negative symptoms while modest D2 receptor blockade in limbic system responsible for decrease in positive symptoms. Atypical Antipsychotics
  41.   At least 60% to 65% occupation of D2 receptors antagonism is necessary to decrease positive antipsychotic symptoms, whereas 77% or more blockade is associated with extrapyramidal side effects.  One of the most common adverse effects of newer antipsychotics is weight gain.  Other adverse effects include sedation and diabetes.  Atypical antipsychotic drugs have varying degree of other receptors blocking activity:  Clozapine: D4 = α1 ˃ 5-HT2 = M ˃ D2 = D1 = α2  Quetiepine: 5-HT2 = D2 = α1 = α2  Risperidone: 5-HT2 ˃˃ α1 ˃ H1 ≥ D2 ˃ α2 ˃˃ D1 Atypical Antipsychotics
  42.  Atypical Antipsychotics
  43.   1. Sedation:  Although sedation is most commonly associated with chlorpromazine and clozapine, it is primarily related to dosage with other antipsychotics.  2. Autonomic Side Effects:  Some antipsychotic drugs are associated with changes to the QT interval measured on the elecrocardiogram (ECG) and, if given in high doses, may increase the risk of sudden cardiac death due to α adrenergic blockage.  Anticholinergic side effects such as dry mouth, constipation, blurred vision are particularly associated with piperidine phenothiazines.  Postural hypotension, palpitation, inhibition of ejaculation and photosensitivity are associated with the aliphatic phenothiazines. Adverse Effects
  44.   3. Extrapyramidal Side Effects:  Side effects such as akathisia, dystonia, parkinsonian effects and tardive dyskinesia are associated with typical antipsychotic drugs and occur frequently, particularly with piperazine phenothiazines such as trifluoperazine, fluphenazine and butyrophenones such as haloperidol.  Akathisia:  It is defined as the inability to sit and being functionally motor restless. It is characterized by restlessness, convulsions, feeling of discomfort uncontrollable & without any anxiety. The use of non-selective β blocker can provide relief.  Dystonia:  It is a state of abnormal tonicity, sometimes described as a severe “muscle spasm”, characterized spasm of muscles of tongue, face neck and back; Pharangeal laranreal dystonia is life threatening. Treatment can be made by using benzodiazepine and anticholinergic drug. Adverse Effects
  45.   Puedoparkinsonism:  It results due to blockadge of D2 receptor in nigrostratial pathway.  With typical manifestations rigidity, tremor, hypokinesia, , mask- like facial expression, micrographia, slowed speech, postural imbalance and decreased arms wing; between 1-4 weeks of therapy and persists unless dose is reduced.  Treatment involve restoration of cholinergic doapaminergic balance by using centrally acting antimuscarinic drugs like trihexyphenidyl, procyclidin, biperiden and dopamine agonist.  Tardive Dyskinesia:  It is a syndrome characterized by abnormal involuntary movements occurring late in onset in relation to initiation of antipsychotic therapy.  The classic description is the buccal-lingual-masticatory (BLM) syndrome, or orofacial movements causing involuntary facial tics or random uncontrolled muscle movements of the hands, feet, limbs trunk. Adverse Effects
  46.   4. Neuroleptic Malignant Syndrome (NMS):  The NMS is a rare but serious complication of antipsychotic drug treatment. The primary symptoms are rigidity, fever, diaphoresis, confusion and fluctuating consciousness.  Confirmation can be sought through detection of elevated levels of creatinine kinase.  The onset is particularly associated with high-potency typical drugs such as haloperidol, recent and rapid changes to dose and abrupt withdrawal of anticholinergic drugs.  Treatment usually requires admission to a medical ward and withdrawal of all antipsychotic drugs. Intravenous dantrolene may benefit as skeletal muscle relaxant. The Dopamine agonist Bromocriptine in large doses has been found useful to reduce rigidity and fever. Adverse Effects
  47.   5. Hormonal Effects and Sexual Dysfunction:  Blockade of D2 receptor in pituitary gland results into the effect on prolactin. This may result in galactorrhoea, missed menstrual periods, loss of libido in female and gynaecomasia in male.  Some studies have suggested very high levels of sexual dysfunction with some antipsychotic drugs such as risperidone and amisulpride.  These drug also inhibit FSH and LH release results in amenorrhoea and inhibition of ovulation.  6. Miscellaneous:  Weight gain  Jaundice  Photosensitivity Adverse Effects
  48.   Clozapine:  The first of the new generation, clozapine is the only drug that has been shown to be effective where other antipsychotics have failed.  Clozapine was developed as an antipsychotic drug during the 1960s.  It is the drug of choice for treatment resistant schizophrenia.  It has only weak D2 blocking activity.  Selectivity of receptor are: 5-HT2>H1=M1>α1=D4>D2=D1  Adverse Effects:  Produce no or few extrapyramidal symptoms.  Major side effect is agranulocytosis.  Other side effects are sedation, unstable BP, tachycardia, urinary incontinence, weight gain and precipitation of diabetes. Clozapine
  49.   Usage:  It decreases hallucination and helps to prevent suicide in people who are likely to try to harm themselves.  It helps to think more clearly and positively and take part in everyday life.  Pharmacokinetic:  Metabolized in liver by CYP34A with average half-life 12 hours.  Bioavailability is 60 to 70%. Clozapine
  50.   1. Chlorpromazine + Propranolol:  Increase plasma concentration of chlorpromazine  2. Haloperidol / Risperidone / Olanzepine + Carbamazepine:  Accelerates the metabolism of antipsychotic drug  3. Phenothiazine + TCA (Tricyclic Antidepressants):  Increased antimuscarinic effects such as dry mouth and blurred vision  4. Clozapine + SSRI (Selective Seretonin Receptor Inhibitor):  Increase plasma concentration of clozapine Drug Interaction