Description

A primary mood disorder characterized by a depressed mood and/or a markedly decreased interest or pleasure in normally enjoyable activities most of the day, almost every day for at least 2 weeks, and causing significant distress or impairment in daily functioning

Epidemiology

• 2–10% of community-dwelling elderly
• 5–10% seen in primary care clinics
• 10–37% of hospitalized elderly patients
• 12–27% of nursing home residents

• The Global Burden of Disease Study (2015) estimated the prevalence of depressive disorders among older adults (>60 years old) of 4–6% among males and 5–8% among females.
• Suicide is the 11th leading cause of death in the United States for all ages.
  • The elderly account for 24% of all completed suicides with the highest rates for males aged >85 years.

Etiology and Pathophysiology

• A complex interaction between heritable and environmental factors
• Abnormalities in neurotrophins, neurogenesis, neuroimmune systems, and neuroendocrine systems

Possible mechanisms, including genetic influences on

• Monoamine transmission and associated transcriptional and translational activity and dysregulation in biologic processes and proteostasis involving C-peptide, FABP-liver, and ApoA-IV proteins

Risk Factors

• Female sex
• Lower socioeconomic status
• Widowed, divorced, or separated marital status
• Chronic physical health condition(s)
• History of mental health problems
• Family history of depression
• Death of a loved one
• Caregiving
• Social isolation
• Functional/cognitive impairment
• Lack/loss of social support
• Significant loss of independence
• Uncontrolled or chronic pain
• Insomnia/sleep disturbance

Commonly Associated Conditions

Chronic disease (e.g., stroke, cancer, Parkinson disease)