Difference Between Akinesia and Akathisia (With Table)

Navigating Movement Disorders: Akinesia vs. Akathisia

An Overview of Movement Disorders

• Akinesia and akathisia are frequently encountered in movement disorders, representing distinct clinical entities with unique characteristics, symptoms, and underlying mechanisms. While both conditions involve alterations in motor function, they differ fundamentally in their presentation, causes, and response to treatment.

Understanding Akinesia

Defining Akinesia

• Akinesia refers to the loss or impairment of voluntary muscle movement. It is associated with a significant reduction in the initiation and execution of purposeful movements, leading to motor inertia.

Key Features of Akinesia

1. Lack of Movement: The hallmark feature of akinesia is a profound reduction or absence of voluntary movements. Individuals with akinesia may struggle to initiate movements or find it challenging to sustain ongoing actions.
2. Rigidity: Akinesia is frequently accompanied by muscle rigidity, making it difficult for affected individuals to achieve fluid and coordinated movements.
3. Associated with Parkinson’s Disease: Akinesia is a prominent feature of Parkinson’s disease, a neurodegenerative disorder characterized by the loss of dopamine-producing neurons in the brain.
4. Bradykinesia: Bradykinesia, which refers to slowness of movement, is seen in conjunction with akinesia in conditions like Parkinson’s.

Causes and Mechanisms

• Akinesia is primarily associated with dysfunction in the basal ganglia, a group of brain structures responsible for motor control and coordination. In Parkinson’s disease, the loss of dopamine-producing neurons within the basal ganglia leads to akinesia and related motor symptoms.

Treatment

• Treatment for akinesia, particularly in the context of Parkinson’s disease, involves using dopaminergic medications, such as levodopa, to replenish dopamine levels in the brain. Physical therapy and other rehabilitative interventions may also help improve motor function.

Understanding Akathisia

Defining Akathisia

• Akathisia is a neuropsychiatric disorder characterized by an intense and distressing sensation of inner restlessness and a compelling urge to move. It can manifest as an overwhelming need to shift positions or walk continuously.

Key Features of Akathisia

1. Restlessness: Akathisia is defined by an inner restlessness that can be difficult to describe but is intensely uncomfortable. Individuals with akathisia feel they need to move to alleviate this discomfort.
2. Compulsive Movements: To relieve the distressing sensation, individuals with akathisia may engage in repetitive, purposeless movements, such as pacing, tapping their feet, or shifting weight from one leg to another.
3. Psychiatric Medication-Related: Akathisia is commonly associated with using certain psychiatric medications, particularly antipsychotic drugs. It can also occur as a side effect of other medications, such as antiemetics or antidepressants.
4. Differentiated from Anxiety: While akathisia can be distressing, it is important to differentiate it from anxiety or agitation related to psychiatric conditions. Akathisia is a distinct neurobiological phenomenon.

Causes and Mechanisms

• The exact mechanisms underlying akathisia are not fully understood, but it is thought to involve dysregulation of dopamine and other neurotransmitters in the brain. Certain medications, particularly those that affect dopamine receptors, can trigger or exacerbate akathisia.

Treatment

• The management of akathisia involves adjusting or discontinuing the causative medication, if possible, under the guidance of a healthcare professional. Medications such as beta-blockers or anticholinergic drugs may be prescribed to alleviate symptoms. In some cases, reducing the dose of the causative medication may also be effective.

Key Differences

Let’s delve into the key differences between Akinesia and Akathisia:

Definition

• Akinesia: Refers to the loss or impairment of voluntary muscle movement, characterized by a profound reduction or absence of purposeful movements.
• Akathisia: A neuropsychiatric disorder characterized by intense inner restlessness and an irresistible urge to move or engage in compulsive movements.

Core Symptoms

• Akinesia: Lack of movement, muscle rigidity, associated with Parkinson’s disease and may involve bradykinesia (slow movement).
• Akathisia: Restlessness, an overwhelming urge to move, compulsive movements (e.g., pacing, tapping), and discomfort alleviated by motion.

Underlying Mechanisms

• Akinesia: Associated with dysfunction in the basal ganglia and a reduction in dopamine levels in the brain, particularly seen in conditions like Parkinson’s disease.
• Akathisia: Mechanisms are not fully understood but are thought to involve dysregulation of dopamine and other neurotransmitters. Often linked to medications affecting dopamine receptors.

Conditions or Disorders

• Akinesia: Commonly associated with Parkinson’s disease but can also occur in other neurological conditions.
• Akathisia: Frequently related to the use of certain psychiatric medications, particularly antipsychotic drugs, but can result from various medication classes.

Sensation

• Akinesia: Characterized by the inability to initiate or sustain movements, with muscle rigidity.
• Akathisia: Defined by an intense, distressing inner restlessness and a compulsion to move or perform repetitive actions.

Treatment

• Akinesia: Typically managed with dopaminergic medications (e.g., levodopa) to restore dopamine levels in the brain, along with physical therapy and rehabilitative interventions.
• Akathisia: Treatment may involve adjusting or discontinuing the causative medication, if possible. Medications like beta-blockers or anticholinergic drugs may be prescribed to alleviate symptoms.

Table: Summary of Differences

Here’s a summary table highlighting the key differences between Akinesia and Akathisia:

Conclusion

Akinesia and akathisia represent distinct clinical entities within the realm of movement disorders. Akinesia is characterized by the loss or impairment of voluntary muscle movement, seen in conditions like Parkinson’s disease, and is associated with dopamine dysregulation in the basal ganglia. In contrast, akathisia manifests as an intense inner restlessness and an irresistible urge to move or engage in compulsive movements. It is frequently linked to certain psychiatric medications and involves dopamine and other neurotransmitter alterations.

Understanding the differences between these two conditions is essential for accurate diagnosis and appropriate management. While akinesia may respond to dopaminergic medications and rehabilitative interventions, akathisia necessitates adjustments to the causative medication under the guidance of a healthcare professional.