The merits of actively assessing and treating depression in elderly individuals with cognitive impairment
It’s easy to assume that learning of a dementia diagnosis is inherently depressing. However, the relationship between dementia and behavioral health is more complex. The literature suggests that about 20% of individuals with dementia will develop depression during the course of their illness.
Depression is not just a reaction to awareness of cognitive decline or a frightening diagnosis. Depression instead appears to have a bi-directional relationship with dementia. While evidence is lacking that depression directly causes dementia, depression is likely to be a strong risk factor for subsequent development of cognitive impairment.
A study reported in Neurology followed 1,700 individuals with no sign of cognitive impairment at baseline. Evidence of high levels of depressive symptoms prior to diagnosis of cognitive impairment was associated with the rate and severity of cognitive decline. The researchers found that formal depression may actually wane in the later stages of dementia, suggesting that the declining awareness in late-stage dementia may blunt the depressive symptoms.
A study published in The Lancet Psychiatry shed additional light on the relationship between the two conditions. A decade-long follow-up of 3,325 subjects found a relationship between the course of depression and subsequent development of dementia. Individuals with steady worsening of depression after age 55 had a higher risk of dementia than subjects with mild or intermittent depression. The authors consider this depressive subtype as a potential early stage of dementia, possibly sharing common underlying causes.
How neuropsychological assessment of depression can help
The presence of depressive symptoms in the context of mild cognitive impairment (MCI) or subjective complaints of memory loss deserves formal assessment and vigorous treatment, providing an opportunity to alter the course of cognitive decline as well as impacting the quality of life and overall health. Major depression affects concentration, attention, sleep and energy. The apathy and hopelessness associated with depression often affect the individual’s ability to collaborate with their physician, take medications as prescribed, or engage in recommended lifestyle changes (e.g., smoking cessation, diet, regular exercise).
BrainCheck offers rapid cognitive assessment as well as tools for assessing mood, such as the Patient Health Questionnaire-9 (PHQ-9) and the Geriatric Depression Scale. After establishing a baseline, use of BrainCheck and mood screeners can help the physician evaluate response to treatment with antidepressants and/or psychotherapy and can be an essential tool in determining a differential diagnosis of depression vs. early-stage dementia.
On our next post, we’ll focus on anxiety in the elderly, with a particular focus on risks of polypharmacy.
References
- Mirza, S.S., Wolters, F.J., Swanson, S.A., Koudstaal, P.J., Hofman, A., Tiemeier, H., & Ikram, M.A. (2016). 10-year trajectories of depressive symptoms and risk of dementia: a population-based study. The Lancet Psychiatry, 3(7), 628-635. https://doi.org/10.1016/S2215-0366(16)00097-3
- Wilson, R.S., Capuano, A.W., Boyle, P.A., Hoganson, G.M., Hizel, L.P., Shah, R.C., Nag, S., Schneider, J.A., Arnold, S.E., & Bennett, D.A. (2014). Clinical-pathologic study of depressive symptoms and cognitive decline in old age. Neurology, 83(8), 702-709. https://doi.org/10.1212/WNL.0000000000000715
