The topical clinical-pathologic study by Wilson et al. provided exciting new evidence that depressive symptoms in old age have an association with cognitive decline independent of the neuropathologic hallmarks of dementia. [1] It is increasingly apparent that late-life depression is associated with an increase in risk of developing all-cause dementia. [2] However, several qualifications may be necessary.
Most likely, only a small fraction of this self-selected sample would fulfill DSM-IV criteria for a major depressive episode. It would be valuable to ascertain if patients with clinically significant depression at baseline, or during follow-up, differed from the rest regarding neuropathologic markers. In this context, it is worth mentioning that the presence of comorbid depression in Alzheimer dementia (AD) has been demonstrated to correspond to increases in AD-related neuropathologic changes beyond age, gender, level of education, and cognitive status. [3] Moreover, lifetime history of depression in AD patients has shown association with higher levels of plaque and tangle formation in hippocampus. [4]
The authors did not provide information on the use of psychotropic agents (antidepressants or lithium) in this sample. Conceivably, antidepressants or mood stabilizers may not only counteract depression, but also exert neuroprotective and neurotrophic actions extending beyond mood effects. [5]
1. Wilson RS, Capuano AW, Boyle PA, et al. Clinical-pathologic study of depressive symptoms and cognitive decline in old age. Neurology Epub 2014 July 30.
2. Diniz BS, Butters MA, Albert SM, et al. Late-life depression and risk of vascular dementia and Alzheimer's disease: systematic review and meta-analysis of community-based cohort studies. Br J Psychiatry 2013;202:329-335.
3. Rapp MA, Schnaider-Beeri M, Purohit DP, et al. Increased neurofibrillary tangles in patients with Alzheimer disease with comorbid depression. Am J Geriatr Psychiatry 2008;16:168-174.
4. Rapp MA, Schnaider-Beeri M, Grossman HT, et al. Increased hippocampal plaques and tangles in patients with Alzheimer disease with a lifetime history of major depression. Arch Gen Psychiatry 2006; 63:161-167.
5. Cirrito JR, Disabato BM, Restivo JL, et al. Serotonin signaling is associated with lower amyloid-? levels and plaques in transgenic mice and humans. Proc Natl Acad Sci U S A;108:14968-14973.
For disclosures, contact the editorial office at journal@neurology.org.
The topical clinical-pathologic study by Wilson et al. provided exciting new evidence that depressive symptoms in old age have an association with cognitive decline independent of the neuropathologic hallmarks of dementia. [1] It is increasingly apparent that late-life depression is associated with an increase in risk of developing all-cause dementia. [2] However, several qualifications may be necessary.
Most likely, only a small fraction of this self-selected sample would fulfill DSM-IV criteria for a major depressive episode. It would be valuable to ascertain if patients with clinically significant depression at baseline, or during follow-up, differed from the rest regarding neuropathologic markers. In this context, it is worth mentioning that the presence of comorbid depression in Alzheimer dementia (AD) has been demonstrated to correspond to increases in AD-related neuropathologic changes beyond age, gender, level of education, and cognitive status. [3] Moreover, lifetime history of depression in AD patients has shown association with higher levels of plaque and tangle formation in hippocampus. [4]
The authors did not provide information on the use of psychotropic agents (antidepressants or lithium) in this sample. Conceivably, antidepressants or mood stabilizers may not only counteract depression, but also exert neuroprotective and neurotrophic actions extending beyond mood effects. [5]
1. Wilson RS, Capuano AW, Boyle PA, et al. Clinical-pathologic study of depressive symptoms and cognitive decline in old age. Neurology Epub 2014 July 30. 2. Diniz BS, Butters MA, Albert SM, et al. Late-life depression and risk of vascular dementia and Alzheimer's disease: systematic review and meta-analysis of community-based cohort studies. Br J Psychiatry 2013;202:329-335.
3. Rapp MA, Schnaider-Beeri M, Purohit DP, et al. Increased neurofibrillary tangles in patients with Alzheimer disease with comorbid depression. Am J Geriatr Psychiatry 2008;16:168-174.
4. Rapp MA, Schnaider-Beeri M, Grossman HT, et al. Increased hippocampal plaques and tangles in patients with Alzheimer disease with a lifetime history of major depression. Arch Gen Psychiatry 2006; 63:161-167.
5. Cirrito JR, Disabato BM, Restivo JL, et al. Serotonin signaling is associated with lower amyloid-? levels and plaques in transgenic mice and humans. Proc Natl Acad Sci U S A;108:14968-14973.
For disclosures, contact the editorial office at journal@neurology.org.