Aetiology

Depression in old age is the result of a large number of factors. These include biological, psychological, social, spiritual, and personality factors:

• loneliness, for example following bereavement, or because of less social contact. This scenario also adds to the development of metabolic syndrome, leading to increased cortisol and hypothalamic-pituitary-adrenal dysregulation, another major reason for the development of depression. (1)
• poor physical health, particularly where this is disabling or leads to a loss of independence. Common examples include visual or auditory impairment, osteoarthritis.
• precipitation by life events - note that after a bereavement up to 20% are clinically depressed for a year
• depression is more common amongst elderly women than men
• may occur as a side-effect of certain drugs

Reference

1. Butters MA et al. Pathways linking late-life depression to persistent cognitive impairment and dementia. Dialogues Clin Neurosci. 2008;10(3):345-57.