Psychiatric Disease Review: Depression, Anxiety, and ADHD

Definition and Context: - The term ‘depression’ describes both a normal emotional experience and a psychological disorder. - Major depression is characterized by persistent and severe symptoms that significantly impair daily functioning. - Depressive disorders are categorized into: - Major Depressive Disorder - Dysthymia

Mood Symptoms: - Sadness - Irritability - Pessimism - Self-reproach - Suicidal thoughts - Hopelessness - Worthlessness - Guilt - Anhedonia (loss of enjoyment/interest in previously pleasurable activities)
Physical Symptoms: - Sleep disturbances: - Hypersomnia (increased sleep) or Insomnia (decreased sleep) - Disturbed sleep patterns (e.g., early morning awakening at around 4-5 am) - Poor energy and fatigue: feeling “tired all the time” - Changes in appetite: can lead to weight gain or loss - Decreased sex drive - Psychomotor agitation (increased restlessness) or retardation (slowed movement) - Vague abdominal or joint pains
Psychological Symptoms: - Poor memory - Difficulty concentrating - Slowed thinking (bradypsychia)

Definition: - A chronically depressed mood that persists for most of the day, on more days than not, for a minimum of 2 years. - Characterized by chronic, less severe depressive symptoms compared to major depressive disorder. - Individuals with dysthymia are at risk of developing major depressive disorder and other psychiatric disorders.

Overview: - Suggests a biochemical basis for the treatment of depression with antidepressants. - Based on studies indicating that drugs alleviating depressive symptoms enhance the action of central nervous system (CNS) neurotransmitters such as serotonin (5HT) and norepinephrine (NE). - Postulates that a functional decrease in the activity of 5HT and NE contributes to the development of depression.
Mechanisms: - Excessive reuptake of NE/5HT results in inadequate neurotransmitter levels in the synapse. - Diminished release of neurotransmitters into the synapse. - Increased degradation of neurotransmitters by monoamine oxidase.

Presynaptic Events: - Vesicles containing neurotransmitters release into the synapse through the terminal bouton.
Postsynaptic Events: - Neurotransmitters bind to receptors on the postsynaptic neuron. - Neurotransmitter reuptake into the presynaptic neuron.

Antidepressants enhance the function of NE and/or 5HT by: 1. Inhibition of Monoamine Reuptake: - Prevents neuronal reuptake of NE and/or 5HT, increasing synaptic activity for these neurotransmitters. 2. Inhibition of Breakdown: - Inhibiting monoamine oxidase raises presynaptic stores of NE and 5HT, enhancing the neurotransmitter effects.

Definition: - Anxiety disorders comprise a group of conditions marked by intense episodes of fearfulness resulting from sympathetic nervous system activation. - Types of anxiety disorders include: - Panic Disorder - Generalized Anxiety Disorder (GAD) - Obsessive-Compulsive Disorder (OCD) - Social Phobia

Characteristics: - Experience of panic attacks defined by: - Neurological symptoms: dizziness, fainting - Cardiac symptoms: tachycardia, chest pain - Respiratory symptoms: shortness of breath, choking sensations - Psychological symptoms: fear of dying, feelings of impending doom - Panic attacks are typically unexpected and may not be linked to external stimuli, lasting around 15 to 30 minutes.
Causes: - Comprise both biological and environmental factors, with a higher likelihood of occurrence in individuals with family history of panic disorder. - Levels of norepinephrine, serotonin, and GABA are associated with panic disorder.
Treatment: - Involves behavioral therapies, psychological counseling, and pharmacotherapy. - Antidepressants have been found effective in managing panic disorder symptoms.

Characteristics: - GAD is marked by prolonged (> 6 months) and excessive worry that is difficult to control. - Symptoms include: - Muscle tension - Poor vigilance (difficulty concentrating) - Exaggerated startle response
Treatment: - Includes anxiolytics (sedatives such as benzodiazepines), antidepressants, and beta-blockers.

Definition: - An anxiety disorder characterized by recurrent obsessions (persistent thoughts) and compulsions (repetitive actions). - Individuals feel compelled to perform behaviors that are distressful and time-consuming, unrelated to environmental conditions.
Treatment: - Behavioral therapy (exposure to feared situations). - Cognitive therapy. - Antidepressants, including SSRIs and Tricyclic Antidepressants (TCAs).

Definition: - An intense, irrational, and persistent fear of being judged or negatively evaluated by others. - Individuals may exhibit anxiety in social situations and often avoid them, impacting their routine and lifestyle.
Treatment: - Behavioral therapy (exposure to feared situations). - Cognitive therapy. - Pharmacotherapy: - Anxiolytics (e.g., benzodiazepines) - Antidepressants (SSRIs and MAOIs) - Beta blockers.

Definition: - A neurobiological condition characterized by developmentally inappropriate levels of inattention, hyperactivity, and impulsiveness, manifesting in various environments (school, home, social settings). - Important to note: ADHD symptoms can be present in contexts beyond classroom settings, such as during play.
Prevalence: - Most common neurobehavioral disorder in children, affecting an estimated 4% to 12% of school-aged children. - Typically diagnosed more frequently in boys than in girls, with a gender ratio ranging from 2:1 to 9:1. - Symptoms serious enough to interfere with functioning in home or school may necessitate treatment. - Symptoms persist in 30% to 50% of patients into adolescence and adulthood, although the symptom profile may change.

Hyperactivity: - Children: Aimless restlessness; fidgets, talks excessively, runs/climbs excessively, cannot play/work quietly. - Adults: Inner restlessness; talk excessively, feel overwhelmed, prefer active jobs; inability to enjoy quiet leisure time.
Inattention: - Children: Difficulty with homework, inattentiveness, forgetfulness, easily distracted. - Adults: Frustration due to organization issues, poor time management, misplacing belongings, preference for multitasking.
Impulsivity: - Children: Blurt out answers, interrupt, cannot wait turns. - Adults: Quick to anger, impulsively shares rude thoughts, changes jobs frequently, risks reckless driving or impulsive sexual behavior.

Neurological Pathways: - The prefrontal noradrenergic pathway (norepinephrine) is crucial for attention maintenance and focus. - The mesocortical pathway (dopamine) is critical for cognitive functioning and executive attention. - Dysregulation in these pathways is implicated in ADHD; increasing DA and NE may improve conditions but may cause cognitive deterioration if excessive.

Therapies Involved: - Behavioral therapy. - Pharmacotherapy options include: - Psychostimulants (first-line therapy that increases norepinephrine and dopamine). - Selective norepinephrine reuptake inhibitors. - Antidepressants that increase monoamine levels (5HT and NE).