Dementia and Delirium
Dementia is not a specific disease, but rather, an umbrella term that refers to a group of conditions that impact on cognition and memory to such an extent that it affects the ability of individuals to perform core daily activities(Verdelho, & Goncalves-Pereira, 2017) .
Delirium, on the other hand, is also not a disease but a group of symptoms arising from a sudden change in the brain which causes emotional disruption and mental confusion thereby leading to disorientation and confusion or difficulties thinking clearly, remembering things, or maintaining focus (Verdelho, & Goncalves-Pereira, 2017).
The major difference between delirium and dementia is that delirium develops abruptly over hours or days rather than months and years, and, unlike dementia, it is usually temporary and typically resolves itself once the underlying condition has been addressed.
Regarding clinical presentation, delirium and dementia can sometimes share common clinical features (Verdelho, & Goncalves-Pereira, 2017).However, they are two separate mental states that have certain distinct and critical differences that can be recognized from accurate diagnosis (Lippmann, & Perugula, 2016).
The major clinical presentations of delirium include abnormal changes in the levels of thinking and consciousness, difficulty maintaining focus, poor retention ability for new information, disorientation and confusion, visual hallucinations, drowsiness, and sometimes loss of muscle control (Lippmann, & Perugula, 2016).
The clinical features of dementia, on the flip side, include cognitive fluctuations, visual hallucinations, sleep disorders, dysautonomia, and difficulty with memory, judgement, reasoning, and judgement (Lippmann, & Perugula, 2016).
Alzheimer’s disease is presently the major cause of dementia with the pathophysiology of dementia following a cortical-subcortical degeneration of ascending cholinergic neurons and large pyramidal cells in the cerebral cortex (Tible, Riese, Savaskan, & Gunten, 2017).
The pathophysiology of delirium is presently not well understood but evidence suggests that it arises as a result of different pathogenetic mechanisms which disrupt neurotransmission (Maldonado, 2017). The assessment of dementia entails obtaining history from both the patient as well as a reliable informant and then conducting a physical as well as a cognitive examination of the patient (Hugo, & Ganguli, 2014).
Distinctively, delirium is assessed using validated tools such as the Confusion Assessment Method for the ICU (CAM-ICU) or the Intensive Care Delirium Screening Checklist (ICDSC) (Bush, Tierney, & Lawlor, 2017).
While there are currently no specific diagnostic tests for dementia, the condition is normally diagnosed by ruling out other conditions through appropriate laboratory investigations, general physical and neurological examination, and changes in behavior, thinking, and day-to-day functioning (Hugo, & Ganguli, 2014). Similarly, the diagnosis of delirium is purely clinical as there arecurrently no laboratory tests to diagnose delirium.
The DSM-V criteria for diagnosis delirium includes attention disturbance that develops abruptly over a short period of time, additional cognition disturbance, the disturbances are not attributed to any other neurocognitive disorder, and evidence from history and physical examination showing the disturbance is a direct physiological consequence of another medical condition, substance intoxication, or exposure to a toxin, or is because of multiple etiologies (Lawlor, & Bush, 2014).
The treatment of delirium is first composed of addressing any underlying triggers of causes – for instance by treating an infection, stopping particular medications, or addressing metabolic imbalances – followed by supportive care that creates a healing environment.
On the other hand, most types of dementia are incurable. However, symptoms can be managed by using a variety of medications such as cholinesterase inhibitors, memantine, or others than treat agitation, sleep disturbances, and depression. Also, occupational therapy and other therapies such as task and environment modification can be used to address certain symptoms and behavior problems.
Bush, S. H., Tierney, S., & Lawlor, P. G. (2017). Clinical Assessment and Management of Delirium in the Palliative Care Setting. Drugs, 77(15), 1623–1643. http://doi.org/10.1007/s40265-017-0804-3
Hugo, J., & Ganguli, M. (2014). Dementia and Cognitive Impairment: Epidemiology, Diagnosis, and Treatment. Clinics in Geriatric Medicine, 30(3), 421–442. http://doi.org/10.1016/j.cger.2014.04.001
|Lawlor, P. G., & Bush, S. H. (2014). Delirium diagnosis, screening and management. Current Opinion in Supportive and Palliative Care, 8(3), 286–295. http://doi.org/10.1097/SPC.0000000000000062|
Lippmann, S., & Perugula, M. L. (2016). Delirium or Dementia? Innovations in Clinical Neuroscience, 13(9-10), 56–57.
Maldonado, J. R. (2017). Delirium pathophysiology: An updated hypothesis of the etiology of acute brain failure. International Journal of Geriatric Psychiatry. https://doi.org/10.1002/gps.4823
Tible, O. P., Riese, F., Savaskan, E., & Gunten, A. V. (2017). Best practice in the management of behavioral and psychological symptoms of dementia. Therapeutic Advances in Neurological Disorders, 4(5). 7-13. https://doi.org/10.1177/1756285617712979
Verdelho, A., & Goncalves-Pereira, M. (2017). Neuropsychiatric Symptoms of Cognitive Impairment and Dementia. Cham: Springer International Publishing