Depression

Contents

Depression

• Symptoms

• Pathogenesis

Objectives

At the end of this lecture, student will be able to

• Explain the definition of depression

• Explain the etiology of depression

• Explain the pathophysiology of depression

Depression

Depression is a state of low mood and aversion that can affect a persons’s thoughts, behavior, feelings, and sense of well being

Causes of Depression

• Family History

• Having a family members who have depression may increase a person’s risk

• Imbalances of certain chemicals in the brain may lead to depression

• Major Life Changes

• Positive or negative events can trigger depression. Examples include the death of a loved one or a promotion

• Major Illnesses such as heart attack, stroke or cancer may trigger depression

• Certain medications used alone or in combination can cause side effects much like the symptoms of depression

• Use of Alcohol or other Drugs can lead to or worsen depression

• Depression can also occur for no apparent reason!

Types of depression

• Major depression

• Inability to enjoy life and experience pleasure

• Symptoms are constant, ranging from moderate to severe

• Some people experience just a single depressive episode in their lifetime, but more commonly, major depression is a recurring disorder

• Atypical Depression

• Specific symptom pattern, including a temporary mood lift in response to positive events

• Other symptoms include weight gain, increased appetite, sleeping excessively, a heavy feeling in the arms and legs

• Atypical depression responds better to some therapies and medications than others

• Bipolar disorder

People with this type of illness change back and forth between periods of depression and periods of mania (an extreme high)

• Symptoms of mania may include:

• Less need for sleep

• Overconfidence

• Racing thoughts

• Reckless behavior

• Increased energy

• Mood changes are usually gradual, but can be sudden

• Season affective disorder

This is a depression that results from changes in the season. Most cases begin in the fall or winter, or when there is a decrease in sunlight

Depression Pathophysiology

• Biogenic amine hypothesis: Decreased brain levels of the neurotransmitters norepinephrine (NE), serotonin (5-HT), and dopamine (DA)

• Postsynaptic changes in receptor sensitivity: Changes in sensitivity of NE or 5-HT₂ receptors may relate to its onset

• Dysregulation hypothesis: A failure of homeostatic regulation of neurotransmitter systems, rather than absolute increases or decreases in their activities

Symptoms of depression

• Vary from person to person

• 2 key signs - loss of interest in things you like to do and sadness or irritability

Additional signs of depression

• Feeling empty

• Inability to enjoy anything

• Hopelessness

• Loss of sexual desire

• Loss of warm feelings for family or friends

• Feelings of self-blame or guilt

• Loss of self esteem

• Inexplicable crying spells, sadness or irritability

• Changes in behavior and attitude

These may include:

• General slowing down

• Neglect of responsibilities and appearance

• Poor memory

• Inability to concentrate

• Suicidal thoughts, feelings or behaviors

• Difficulty making decisions

Physical complaints

• Sleep disturbances such as early morning waking, sleeping too much or insomnia

• Lack of energy

• Loss of appetite

• Weight loss or gain

• Unexplained headaches or backaches

• Stomachaches, indigestion or changes in bowel habits

Summary

• Depression is a state of low mood and aversion that can affect a person's thoughts, behavior, feelings, and sense of well being

• Etiology: family history, major life changes, drugs, work

• Decreased brain levels of the neurotransmitters norepinephrine (NE), serotonin (5-HT), and dopamine (DA), changes in sensitivity of NE or 5-HT₂ receptors - failure of homeostatic regulation of neurotransmitter systems, rather than absolute increases or decreases in their activities