definition classification etiology epidemology pathophysiology symptoms diagnosis

1. WHAT
IS
SCHIZOPHRENIA?
Dr. Nikhitha Valluri,
Assistant Professor,
Sree Dattha Institute of
Pharmacy.

2. DEFINITION :
Schizophrenia is a complex, chronic mental health disorder characterized by an array of
symptoms, including delusions, hallucinations, disorganized speech or behaviour, and
impaired cognitive ability.

3. EPIDEMIOLOGY :
Schizophrenia affects more than 21 million people worldwide. One in two people
living with schizophrenia does not receive care for the condition.
More than 1.1 % of USA population is affected by the Schizophrenia.
The prevalence of the disorder seems to be equal in males and females, although
the onset of symptoms occurs at an earlier age in males than in females.
Males tend to experience their first episode of schizophrenia in their early 20s,
whereas women typically experience their first episode in their late 20s or early
30s.

4. ETIOLOGY :
Genetics:
o Genetic in origin: General population 1%.
o Monozygotic twins 47%.
o Dizygotic twins 12%.
o One schizophrenic parent 12%.
o Two schizophrenic parents 40%.
o First-degree relative 12%.
o Second-degree relative 5-6%
Viral hypothesis –exposure to influenza.
Immune dysfunctions: – Anticardiolipin antibody and antinuclear antibody are increased in
patients with schizophrenia in some but not all studies. Two other markers relevant to
autoimmune function, impaired T lymphocyte proliferative response to the mitogen
phytohem agglutinin and impaired IL-2 production, have shown alterations in patients with
schizophrenia.

5. Birth complications:
Hypoxia – The hippocampus and some neocortical regions are particularly sensitive to
shortfalls in oxygen.
Thus, one proposed mechanism for a role of pregnancy and birth complications in the cause
of schizophrenia involves hypoxia-mediated damage to these areas.
Some studies suggest that the rate of obstetric complications are higher in early-onset
schizophrenia, occur more often in males, in people with prominent negative symptoms,
and no family history of schizophrenia.

7. PATHOPHYSIOLOGY :
• Increased ventricular size and decreased grey matter, have been reported.
• Schizophrenia causation theories include genetic predisposition, obstetric complications,
increased neuronal pruning, immune system abnormalities, neurodevelopmental disorders,
neurodegenerative theories, dopamine receptor defect, and regional brain abnormalities
including hyper- or hypo-activity of dopaminergic processes in specific brain regions.
• Positive symptoms may be more closely associated with dopamine receptor hyperactivity in
the meso caudate, whereas negative and cognitive symptoms may be most closely related to
dopamine receptor hypofunction in the prefrontal cortex.
• Glutamatergic dysfunction. A deficiency of glutamatergic activity produces symptoms similar
to those of dopaminergic hyperactivity and possibly schizophrenic symptoms.
• Serotonin (5-hydroxytriptamine [5-HT]) abnormalities. Schizophrenic patients with abnormal
brain scans have higher whole blood 5-HT concentrations, which correlate with increased
ventricular size.

8. CLINICAL PRESENTATION
Symptoms of the acute episode may include:
 being out of touch with reality;
 hallucinations (especially hearing voices);
 delusions (fixed false beliefs);
 ideas of influence (actions controlled by external influences);
 disconnected thought processes (loose associations);
 ambivalence (contradictory thoughts);
 flat, inappropriate, or labile affect;
 autism (withdrawn and inwardly directed thinking);
 uncooperativeness, hostility, and
 verbal or physical aggression;
 impaired self-care skills;
 and disturbed sleep and appetite.

9. After the acute psychotic episode has resolved, typically there are residual features
E.g . anxiety, suspiciousness,
lack of motivation, poor insight,
impaired judgment, social withdrawal,
difficulty in learning from experience, and
poor self-care skills.
Comorbid substance abuse and nonadherence with medications are common

10.  Positive symptoms – delusions, disorganized speech (association disturbance),
hallucinations, behavior disturbance (disorganized or catatonic), and illusions.
 Negative symptoms – alogia (poverty of speech), avolition, flat affect, anhedonia, and
social isolation.
 Cognitive dysfunction– impaired attention, working memory, and executive function.

11. DIAGNOSIS :
• The Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-5), specifies the
following diagnostic criteria:
✓ Continuous symptoms that persist for at least 6 months with at least one month of active
phase symptoms (Criterion A) and may include prodromal or residual symptoms.
❖ Criterion A: For at least 1 month, there must be at least two of the following present for a
significant portion of time: delusions, hallucinations, disorganized speech, grossly
disorganized or catatonic behavior, and negative symptoms.
At least one symptom must be delusions, hallucinations, or disorganized speech.
❖ Criterion B: Significantly impaired functioning

12. THANK YOU