The clinical challenge of treating geriatric depression with cognitive impairment is determining the extent to which cognitive changes are caused by depression versus underlying brain pathology. This slideshow provides a list of elements that are important to a comprehensive evaluation of geriatric depression.
With the growing aging population in the United States and many other countries, it is important for mental health professionals to develop skills to diagnose and treat cognitive impairment in older patients with depression. the co-occurrence of depression and cognitive impairment doubles every 5 years after the age of 70 years. The first step of an extended evaluation is to perform the psychiatric interview focusing on current symptoms, stressor (bereavement, illness, interpersonal conflicts), history of previous episodes, and previous response to treatment.
Ask specific questions about suicidal ideation, suicidal intent, and history of suicide attempts. Clinical screening questionnaires should not be used to formally diagnose depression or suicidality, but they do provide important information to help identify at-risk individuals. The Beck Depression Inventory (BDI-II) is a widely used scale for these purposes. Although it was not meant specifically for older adults, it can be useful to survey suicidal ideation and has item content consistent with DSM-IV diagnostic criteria for depression. A score of 15 is often considered to be the lower range of mild but clinically significant depression. The 15-question Geriatric Depression Scale: Short Form (GDS-S) was developed as a basic screening measure for depression in older adults. A score of higher than 5 indicates that a more thorough clinical investigation is needed. It is a generally valid measure of mild-to-moderate depression in Alzheimer patients with mild-to-moderate dementia.
With or without cognitive impairment, the occurrence of depression in later life is a clinical concern. Obtain a family history of depression, other psychiatric illnesses, and dementia including age at onset, as well as current perceptions of family support. Given the possibility of impairments in reporting cognitive and functional behaviors, clinicians should try to obtain collateral information from family members, particularly with suspected dementia, where family is often the first to notice subtle cognitive changes.
Cognitive impairment and depression are common among older adults, and the combination of these 2 conditions may lead to persistent difficulties with both cognition and mood, as well as everyday living. Survey the patient and family members about performance of daily activities, focusing on changes in performance or involvement, as well as current level and recent changes in community involvement. It is important to carefully assess functional activities to determine whether deficits are caused more by loss of knowledge or ability (Alzheimer disease) or whether they are caused by loss of interest or motivation (depression and some dementia).
One important but perhaps overlooked aspect of diagnosing either depression or cognitive impairment is a thorough review of risk factors and medical conditions that can be a primary cause or exacerbating element in both these conditions. This is particularly important in geriatric mental health. Document comorbid or contributing medical conditions (eg, hypothyroidism, chronic pain), with a special emphasis on a comprehensive history of vascular risk factors, as well as a careful review of currently prescribed and over-the-counter medications.
It is essential to rule out medical conditions that may present as depression or a decline in cognition. Laboratory tests—such as a complete blood cell count, thyroid-stimulating hormone level, HIV/STD, vitamin B12/folate levels—will help to determine medical contributors.
Common neuropsychological deficits in late-life depression and clinical correlates include information processing speed, attention and concentration, executive functions, and memory. Neuroimaging may be indicated (brain MRI is preferred over CT) in the context of cognitive impairment, focal neurological findings, and/or significant vascular risk factors.