Difference Between Schizophrenia and Alzheimer’s

The key difference between Schizophrenia and Alzheimer’s is that the Schizophrenia is a psychiatric illness, but Alzheimer’s is a neurological disorder.

Schizophrenia and Alzheimer’s disease are chronic debilitating diseases that severely hinder the patient’s ability to maintain a normal life. Schizophrenia is a long-term mental disorder, involving a breakdown in the relation between thought, emotion, and behaviour leading to faulty perception, inappropriate actions, and feelings, withdrawal from reality into fantasy and delusions and a sense of mental fragmentation. Alzheimer’s, on the other hand, is widely regarded as the commonest cause of dementia.

CONTENTS

1. Overview and Key Difference
2. What is Schizophrenia
3. What is Alzheimer’s
4. Similarities Between Schizophrenia and Alzheimer’s
5. Side by Side Comparison – Schizophrenia vs Alzheimer’s in Tabular Form
6. Summary

What is Schizophrenia?

Schizophrenia is a long-term mental disorder of a type involving a breakdown in the relation between thought, emotion, and behaviour leading to faulty perception, inappropriate actions, and feelings, withdrawal from reality into fantasy and delusions and a sense of mental fragmentation.

Based on the clinical features, schizophrenia has been divided into two categories as the acute syndrome and chronic syndrome. The functional impairments are seen only in the chronic form of the disease.

Acute Syndrome

Clinical Features

• Appearance and behaviour – Preoccupied, withdrawn, inactive, restless, noisy, inconsistent
• Mood – Mood change, blunting, incongruity
• Disorders of thinking – Vagueness, formal thought disorder
• Hallucinations – Auditory, visual, tactile and etc.
• Primary and secondary delusions
• Impaired attention and insight, but memory and orientation are normal.

Chronic Syndrome

Clinical Features

• Lack of drive and activity
• Social withdrawal
• Abnormalities of behavior
• Abnormalities of movements – Stupor, excitement, abnormal tonus
• Speech – Reduced in amount, evidence of thought disorder
• Mood – Mood change, blunting, incongruity
• Auditory hallucinations are predominantly seen
• Systematized and encapsulated delusions
• Age disorientation
• Attention and memory are normal

The clinical picture of schizophrenia can vary depending on several factors such as

• The age of onset – Adolescents in their late adolescence and young adults are more prone to get schizophrenia. In these age groups mood disturbances, thought disturbances and behavioral disruptions are more pronounced.
• Gender

The severity of clinical features is high in males than in females

• Sociocultural background

Diagnostic Criteria

• Schneider’s first-rank symptoms
• Other symptoms such as loosening of association that frequent seen in schizophrenic patients but are less discriminating than the first rank symptoms
• Impaired social and occupational functioning
• A minimum duration
• The exclusion of organic mental disorder, major depression, mania or prolongation of autistic disorder.

Aetiology

• Genetic factors such as family history of schizophrenia
• Abnormalities of pregnancy and delivery
• Maternal influenza
• Fetal malnutrition
• Urban birth
• Migration
• Winter birth
• Early cannabis consumption

The prognosis of schizophrenia varies depending on the stage of disease progression

Management

With the patient’s permission, blood and urine samples should be taken for further investigations to exclude the possibility of any substance abuse. Hospital admission is recommended depending on the severity of the clinical symptoms.

During the hospital management of a schizophrenic patient, treatment can include therapy with antipsychotic drugs Furthermore, it is important to encourage the patient to engage in different activities that are helpful in improving his or her mentality. Counseling for both patient and family is an important aspect of the management.  If the patient shows signs of improvement, the medication can be discontinued after 6 months, provided the patient is under surveillance for possible relapses. A poor prognosis may call for long-term drug therapy.

What is Alzheimer’s?

Alzheimer’s disease is the most common cause of dementia.

The key clinical features of this condition are

• Memory impairment
• Difficulty with words
• Apraxia
• Agnosia
• Frontal executive function- impairment in planning, organizing, and sequencing
• Visuospatial difficulties and
• Difficulties with orientation in space and navigation
• Posterior cortical atrophy
• Personality
• Anosognosia

The vast amount of research carried out on this subject has unveiled a lot about the molecular pathology related to the disease progression. Deposition of beta-amyloid in amyloid plaques and the formation of tau-containing neurofibrillary tangles are the hallmark features of Alzheimer’s disease. Laying down of amyloid in the cerebral blood vessels can give rise to amyloid angiopathy

First degree relatives have a two times higher risk of getting Alzheimer’s than the normal population. Mutations in the following genes are the cause of autosomal dominant forms of the Alzheimer’s disease.

• Amyloid precursor protein
• Presenilin 1 and 2
• E4 allele of apolipoprotein E

Risk Factors

• Advanced age
• Head trauma
• Vascular risk factors
• Family history
• Genetic predisposition

Whenever there is a clinical suspicion of Alzheimer’s disease, a CT scan of the brain is carried out, which will show degenerative changes such as atrophy in the presence of Alzheimer’s disease.

Management

There is no definitive treatment for Alzheimer’s disease.

Cholinesterase inhibitors can control the neuropsychiatric manifestations such as depression. Moreover, Memantatidine is effective in controlling the disease progression and symptoms. Anti-depressants are prescribed when necessary, along with the drugs such as zolpidem that can minimize the sleep disturbances.

What are the Similarities Between Schizophrenia and Alzheimer’s?

• Both diseases can impair the functional capacity of the patient
• They can affect cognitive functions such as memory

What is the Difference Between Schizophrenia and Alzheimer’s?

Schizophrenia is a long-term mental disorder of a type involving a breakdown in the relation between thought, emotion, and behaviour. This leads to faulty perception, inappropriate actions, and feelings, withdrawal from reality into fantasy and delusions and a sense of mental fragmentation. Alzheimer’s disease is a progressive mental deterioration due to generalized degeneration of the brain, which is the most common cause of dementia. Most importantly, schizophrenia is a psychiatric illness while Alzheimer’s is a neurological condition. This is the main difference between Schizophrenia and Alzheimer’s.

Furthermore, some of the clinical features of schizophrenia include disorders of thinking, hallucinations, and delusions. In contrast, memory impairment, difficulty with words, apraxia, and agnosia are some clinical features of Alzheimer’s.

Moreover, schizophrenia treatment includes therapy with antipsychotic drugs. However, there is no definitive treatment for the Alzheimer’s disease.

Summary – Schizophrenia vs Alzheimer’s

Schizophrenia is a long-term mental disorder involving a breakdown in the relation between thought, emotion and behaviour. Alzheimer’s disease is a neurodegenerative disorder, which is identified as the commonest cause of dementia. Schizophrenia is a psychiatric disease, but Alzheimer’s is a neurological disorder. This difference in categorization is the main difference between Schizophrenia and Alzheimer’s.

Reference:

1. Kumar, Parveen J., and Michael L. Clark. Kumar & Clark clinical medicine. Edinburgh: W.B. Saunders, 2009.

Image Courtesy:

1. “Schizophrenia (Illustration)” By BruceBlaus – Own work (CC BY-SA 4.0)  via Commons Wikimedia
2. “595638” (CC0) via Pixabay