Depression

Basics

Basics

Basics

Description

Description

Description

Primary mood disorder characterized by a sustained feeling of sadness and/or decreased interest in all or most activities once enjoyed, which represents a change from previous state

Epidemiology

Epidemiology

Epidemiology

Prevalence

Prevalence

Prevalence

  • Lifetime prevalence of major depressive disorder (MDD) is 20% (1).
  • Low risk before early teens; highest prevalence in teens and young adults (17% of adults 18 to 25 years old reporting a major depressive episode and 7.1% of ≥26 years old in 2020)

Etiology and Pathophysiology

Etiology and Pathophysiology

Etiology and Pathophysiology

Pathophysiology is poorly understood.

Genetics

Genetics

Genetics

Twin studies suggest 37% concordance.

Risk Factors

Risk Factors

Risk Factors

  • Female > male (2:1)
  • History of anxiety
  • Substance abuse
  • Adverse life events
  • First-degree relative or spouse with depression, bipolar, suicide, substance abuse
  • Presence of chronic medical conditions

General Prevention

General Prevention

General Prevention

Physical activity lowers risk for depression (2).

Commonly Associated Conditions

Commonly Associated Conditions

Commonly Associated Conditions

Bipolar disorder, cyclothymic disorder, grief reaction, anxiety disorders, somatoform disorders, schizophrenia/schizoaffective disorders, conduct disorder, substance abuse, PTSD, fibromyalgia, chronic pain, CAD, MS, diabetes, dementia

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