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Learn More > Depression, Dementia, Delirium
The 3 D's . . . can all manifest with emotional, cognitive, and behavioral symptoms. Indeed, just differentiating mood symptoms for the first two, depression and dementia, can be challenging. Select the left image to enlarge and then compare the similarities and differences. Your physician might be interested in the image at the right, it details some differential diagnostic pathways for depression and selected neuropathologies.  
In our culture, the three terms are often used casually and incorrectly, such as "She's just delirious," or "I think he's demented," or "They're always depressed" . . . yet in everyday practice, each are complex, sometimes tacit, potentially overlapping spectrums which can have significant impact on our lives, on the individual and on the family.
Cognitive, emotional and behavioral signs and symptoms of the 3 D's, unexplained or cohesive, can be better diagnosed, pointing to and responding to a range of management and treatment protocols. 
  • Delirium is life-threatening, characterized by acute and fluctuating onset of confusion, disturbances in attention, disorganized thinking and/or decline in level of consciousness. More common in inpatient than outpatient settings, a very sensitive assessment of history, current functioning and collaborative data can help predict (and prevent) future risk.
  • Dementia is an older label that's now been replaced by the more contemporary label "The Neurocognitive Disorders." These disorders typically include gradual and progressive declines in mental processing ability that affect short-term memory, communication, language, judgement, reasoning, abstract thinking and other biopsychosocial domains. Though there are Mild and Major Cognitive Disorders, the reality is a continuum, worthy of early attention.  
  • Depression is a general term used when a cluster of signs and symptoms, e.g., related to mood, sleep, interest, guilt, energy, concentration, appetite, weight, activity . . . are clinically diagnostic specific to the individual and their context. In most cases, signs and symptoms must be present on most days, for most of the time, and of such incidence that they are out of the ordinary for that individual.
Depression commonly accompanies major medical illness. It can be very difficult to recognize since bodily (or somatic) complaints, as primary presenting concerns, are more much common of depressed older patients, than of depressed younger patients.  
Early identification of the "3 D's"as separate, overlapping and/or a continuum, timely monitoring and correctly applied evidence-based management and treatments, have a significant impact on health and quality of life for everybody including the patient, the caregiver, the family, and the community. 
Alzheimer's Disease (AD)
Although our self-labelling is often misapplied ("I forgot where I put my keys, I must be getting Alzheimers") . . . when it is diagnostically supported, Alzheimer's Disease may be initially characterized by impairment of episodic memory (verbal and non‐verbal). As it progresses, dysfunction in judgement and abstract reasoning, visual construction, verbal fluency and naming is often seen. Being able to document these signs and symptoms varies across individuals and is often specific to their history, prior to illness. Click to enlarge the chart below to better understand "Normal Change vs. Early AD." 
Individuals with Vascular Dementias tend to be more impaired than individuals with Alzheimer's Disease on tests of executive function such as verbal fluency. In contrast, their levels of memory impairment may be less severe than seen in Alzheimer's Disease. 
In Frontotemporal Dementias, letter fluency and executive function are usually worse than in Alzheimer's Disease, while memory performance is usually better.
Lewy Body Dementia symptoms can closely resemble those found in Alzheimer’s and Parkinson’s. It's widely underdiagnosed and characterized by dysfunction in attention, visuospatial tasks, letter fluency, mental tracking and abstract reasoning. 
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