Depression and dementia risk

Depression is a common mental health condition that can affect anyone at any stage of life. In Australia, 9% of males and 14% of females will experience at least one episode of depression during their lifetime. Depression is a risk factor for dementia, but fortunately there are a range of options to treat depression.

Depression and dementia risk

Depression has been linked to an increased risk of dementia in later life (2), but the mechanisms underlying this association are not fully understood. It has been hypothesised that depression may contribute to the onset of dementia by affecting brain health through chronic stress, inflammation, and changes in brain structures such as the hippocampus. Depression can also lead to changes in behaviour that may increase dementia risk, such as reduced self-care, social withdrawal, and physical inactivity.

However, the relationship between depression and dementia is bidirectional. Depression can be part of the dementia prodrome (i.e., an early symptom of an evolving dementia) while some people may develop depression as a response to some of the challenges associated with living with dementia, including cognitive difficulties. Depression can mimic some of the symptoms of dementia (e.g., poor attention and concentration, having difficulty remembering things, changes in mood and behaviour, struggling to do things). This can make it difficult to know if someone is experiencing depression or dementia, but there are some key differences.

 

Dementia

Depression

Onset

Months to years

Weeks to months

Mood

Fluctuates

Low/apathetic

Course

Chronic, with slow deterioration over time

Chronic, responds to treatment

Self-awareness

Likely to hide or be unaware of cognitive deficits

Likely to be concerned about memory impairment

Activities of daily living (ADLs) e.g., showering, dressing, eating, mobility.

May be intact early, impaired as disease progresses

May neglect basic self-care

Instrumental activities of daily living (IADLs) e.g., managing finances, medications, food preparation, shopping.

May be intact early, impaired before ADLs as disease progresses

May be intact or impaired

 Source: Rosalynn Carter Institute for Caregivers


Dementia and depression often co-occur, with residents in long-term care facilities with dementia most at risk of developing depression  (3). Speaking with a GP or geriatrician can help identify the presence of dementia or depression (or both) and the appropriate course of action.

Fortunately, there are a range of treatment options available for depression, including for people living with dementia. Beyond Blue has published a review containing the most effective treatments for depression according to the current evidence. This includes psychological therapies (such as cognitive behavioural therapy), medical treatments (such as antidepressant drugs and transcranial magnetic stimulation), and complementary and lifestyle therapies (such as light therapy for seasonal affective disorder). 

Remember, it is never too early to seek help for low mood or depression and never too late. Some people put off seeking help for a variety of reasons, but it is good for anyone who is feeling down to understand that they can take steps to address their symptoms. If you have concerns about your mood or mental health, your best starting point is your GP. This can be an important step towards improving your quality of life and reducing your risk of dementia.

 

Crisis support services

24 hours, 7 days

Lifeline: 13 11 14 

Suicide Call Back Service: 1300 659 467 

Beyond Blue: 1300 224 636

MensLine Australia: 1300 789 978

Kids Helpline: 1800 551 800

13YARN: 13 92 76

For further information see Mental health resources