anxiety

Anxiety Overview

  • Presentation by: Laura Kravitz

Learning Outcomes

  • Understanding of the term anxiety.

  • Different types of anxiety.

  • Pharmacology and physiology of anxiety.

  • Treatment of anxiety disorders.

Definitions and Nature of Anxiety

  • Anxiety: A ‘normal’ but unpleasant emotional state characterized by feelings of unease that can range from mild discomfort to intense dread.

    • Common and natural in reaction to stressors.

    • Typically self-limiting, resolving after the triggering event has passed.

  • Factors that can exacerbate anxiety:

    • Caffeine

    • Nicotine

    • Alcohol

    • Recreational drugs

Treatment and Management

  • Natural Resolution of Anxiety: In many cases, anxiety can go away naturally or be managed once the causative event is resolved.

  • Treatment Indication: When anxiety becomes intolerable and disabling, interfering with a person's normal lifestyle, intervention is necessary.

Classification of Anxiety Disorders

International Classification of Diseases (ICD):

  • OCD: Classified separately from other anxiety disorders.

Diagnostic and Statistical Manual of Mental Disorders (DSM):

  • Mixed anxiety-depressive disorder: Not classified separately.

  • OCD: Classified separately.

Spectrum of Depression and Anxiety Disorders

  • Categories include:

    • Generalized Anxiety Disorder (GAD)

    • Depression

    • Social Anxiety Disorder (SAD)

    • Panic Disorder

    • Obsessive-Compulsive Disorder (OCD)

    • Post-Traumatic Stress Disorder (PTSD)

Types of Anxiety Disorders

  • Generalized Anxiety Disorder (GAD)

  • Phobic Disorders

  • Panic Disorder

  • Obsessive-Compulsive Disorder (OCD)

  • Mixed Anxiety Disorder

  • Post-Traumatic Stress Disorder (PTSD)

Symptoms Associated with Anxiety Disorders

  • Psychological Symptoms:

    • Poor concentration

    • Fear

    • Anticipation

    • Irritability

    • Restlessness

  • Physical/Somatic Symptoms:

    • Throbbing neck

    • Nausea

    • Sweating

    • Poor appetite

    • Trembling or chills

    • Epigastric pain (discomfort over the heart)

    • Tachycardia (increased heart rate)

    • Excess wind

    • Butterflies in stomach

    • Awareness of missed heartbeats

    • Diarrhea

  • Respiratory Symptoms:

    • Difficulty breathing

    • Breathlessness

    • Faintness

    • Tightness over the chest

    • Tinnitus (ringing in the ears)

    • Dizziness

    • Tingling in hands and feet

  • Musculoskeletal Symptoms:

    • Backache

    • Headache

    • Neck ache

Generalized Anxiety Disorder (GAD)

Clinical Presentation:

  • Characterized by excessive and uncontrollable worry.

  • Includes physical symptoms such as:

    • Motor tension

    • Restlessness

    • Irritability

    • Somatic symptoms such as hyperventilation, tachycardia, and sweating.

  • Comorbidity: Often coexists with major depression, panic disorder, or OCD.

  • 12-month prevalence: 1.7% - 3.4%.

Post-Traumatic Stress Disorder (PTSD)

Clinical Presentation:

  • Result of exposure to a traumatic event.

  • Symptoms include:

    • Emotional numbness or detachment.

    • Intrusive flashbacks or vivid dreams.

    • Fear of re-exposure, leading to avoidance of similar situations.

  • 12-month prevalence: 1.1% - 2.9%.

Obsessive-Compulsive Disorder (OCD)

Clinical Presentation:

  • Characterized by obsessional thinking (e.g., fear of leaving the door unlocked).

  • Compulsive behavior (e.g., repeatedly checking the door).

  • 12-month prevalence: 0.7%.

Social Anxiety Disorder (SAD)

Clinical Presentation:

  • Extreme fear of social situations (e.g., eating in public, public speaking).

  • Fear of humiliation or embarrassment.

  • Avoidant behavior (e.g., not eating at restaurants).

  • Anxious anticipation symptoms such as feeling sick on entering a restaurant.

  • 12-month prevalence: 2.3%.

Panic Disorders

Clinical Presentation:

  • Sudden episodes of severe anxiety, typically lasting 30-45 minutes.

  • Symptoms may include:

    • Shortness of breath

    • Other autonomic symptoms

    • Fear of suffocation or dying

    • Urgent desire to flee.

  • 12-month prevalence: 1.8%.

Prevalence of Anxiety and Related Disorders

  • Lifetime Prevalence of Anxiety Disorders: 25%.

  • Prevalence data:

    • Depression: 17%

    • Social Anxiety Disorder: 13%

    • Post-Traumatic Stress Disorder: 7.8%

    • Generalized Anxiety Disorder: 5%

    • Panic Disorder: 3.5%

    • Obsessive-Compulsive Disorder: 2.5%

Comorbid Conditions

  • Anxiety frequently coexists with other conditions including:

    • Major Depressive Disorder (MDD)

    • Substance abuse

    • Attention-Deficit Hyperactivity Disorder (ADHD)

    • Bipolar disorder

    • Chronic pain and sleep disorders.

Role of Anxiety in Everyday Life

  • Anxiety can be a natural response to perceived danger (involuntary).

    • Fight or Flight Response: A biological reaction to danger that prepares an individual to either face or flee from a threat.

The Yerkes-Dodson Law

  • Describes the relationship between arousal/stress and performance:

    • Performance improves with increased stress only to a certain point, beyond which performance declines.

Drug Treatments for Anxiety

Classification of Treatments

  • Fast Onset Drugs:

    • Effects noted within hours or days.

    • Generally act on amino acid systems (excitatory/inhibitory).

    • Higher risk for tolerance and withdrawal.

  • Delayed Onset Drugs:

    • Effects observed after several weeks.

    • Act on modulatory central pathways (e.g., norepinephrine, serotonin).

    • Lower risk for tolerance and withdrawal.

Overview of Available Drugs by DSM Disorder

Drug Type

Target Disorders

Fast Onset

Slow Onset

Antidepressants (SSRIs, SNRIs, TCAs)

GAD, PD, SAD, PTSD, OCD

Benzodiazepines

Anxiety disorders

Yes

Buspirone

GAD

Yes

Definitions of Terms

  • Sedative: Agent that exerts a calming effect.

  • Anxiolytic: Substance that reduces anxiety.

  • Hypnotic: Agents that induce sleep onset and maintenance.

Key Neurotransmitters in Anxiety

  • Norepinephrine

  • Serotonin

  • Histamine

  • Monoamines

  • GABA (gamma-aminobutyric acid)

  • Glutamate

GABA Receptors and Their Role

  • GABAA Receptors:

    • Involved in the mechanism of action for anxiolytic drugs.

    • Composed of a superfamily of ligand-gated ion channels.

    • Binding sites for GABA, benzodiazepines, barbiturates, and other substances.

  • Mechanism:

    • GABA is released from presynaptic membranes and binds to postsynaptic receptors, increasing chloride ion (Cl-) conductance.

    • Benzodiazepines enhance GABA’s effects by occupying specific binding sites, leading to increased Cl- conductance.

Benzodiazepines

  • Mechanism of Action:

    • Potentiate GABA's action, increase the frequency of channel openings of GABAA receptors.

    • Result in anxiolytic, hypnotic, anticonvulsant, amnesic, and myorelaxant effects.

  • Pharmacokinetic Variability:

    • Differences in duration of action and metabolic activity of metabolites influence clinical choice.

Adverse Effects of Benzodiazepines

  • Physical dependence can develop, particularly at higher doses.

  • Long-term use may result in:

    • Memory issues

    • Increased risk of severe withdrawal symptoms upon abrupt discontinuation, including seizures.

Buspirone

  • Most selective anxiolytic available, with a longer time to develop effects (several weeks).

  • No sedative effect and high safety margin; however, it may cause nervousness and tachycardia.

Adrenoceptor Antagonists

  • Examples: Propranolol

  • Used to treat physical symptoms of anxiety (e.g., palpitations).

  • Adverse effects noted include vivid dreams and hallucinations.

SSRIs and SNRIs

  • Frequently prescribed for general anxiety but can worsen anxiety initially.

  • Treatment needs careful dosage management, often dissolving over 6 weeks.

Non-Pharmacological Treatments

  • Behavioral methods (breathing techniques, relaxation) can alleviate mild anxiety.

  • Cognitive Behavioral Therapy (CBT): Equally effective as SSRI treatment for panic disorders and GAD without clear advantages of combined therapies.

Case Study Overview

  • Example Case:

    • Ms. AC, a personal assistant, faces anxiety about dining in public due to her new job responsibilities.

Questions for Consideration

  1. Identify immediate drug relief options for Ms. AC’s symptoms.

  2. Determine long-term treatment approaches for her condition.

  3. Consider appropriate interventions for other anxiety scenarios.

References

  • Dávila-García, M. (Year). Sedative Hypnotics and Anxiolytics. Howard University Department of Pharmacology.

  • Horton-Szar Dan (2012). Pharmacology Crash Course, 4th Edition.

  • Piper, B. Sedative and Hypnotic Agents 1 & 2. Husson University.

  • Stahl, S. (2008). Essential Psychopharmacology.

  • Howland and Mycek (2006). Lippincott's Illustrated Reviews.

  • Walker and Whittlesea online.