II Main Neuropsychiatric Symptoms and Syndromes in Dementia
Delirium and Dementia in Older People: A Complex Link
Elizabeta B. Mukaetova-Ladinska, Andrew Teodorczuk, Tien K. Khoo, and Joaquim Cerejeira
Abstract Delirium is a clinical syndrome requiring urgent medical attention. The early diagnosis of this medical emergency is essential to facilitate prompt treatment and management. In older people, the accurate diagnosis of delirium is often hampered by subjective and objective ambiguities, including lack of medical history and informants, changes in person’s surroundings, sensory deprivation, as well as their potential comorbidities and polypharmacy. In the current review, we address the difficulties in diagnostic accuracy between delirium and dementia. We review the latest diagnostic criteria and screening instruments to aid the diagnosis of delirium and how to differentiate between acute (delirium) and chronic (dementia) brain failure. In addition, we also provide an in-depth summary on underlying neurobiological substrates of delirium and address the management (i.e., prevention and treatment) of delirium.
E.B. Mukaetova-Ladinska (*)
Campus for Ageing and Vitality, Institute of Neuroscience, Newcastle University,
Westgate Road, Newcastle upon Tyne NE4 5PL, UK
School of Medicine & Menzies Health Institute Queensland, Griffith University,
© Springer International Publishing Switzerland 2017 143
A. Verdelho, M. Gongalves-Pereira (eds.), Neuropsychiatric Symptoms of Cognitive Impairment and Dementia, Neuropsychiatric Symptoms of Neurological Disease, DOI 10.1007/978-3-319-39138-0_7
Keywords Delirium • Older people • Delirium etiology • Diagnostic criteria • Delirium screening instruments • Dementia • Delirium prevention • Delirium treatment
The significant rise in human life expectancy is a global phenomenon, affecting both developed and developing countries. It is expected that in the following 20 years, in the UK alone, there will be an increase by 53 % of people older than 65 years. There are currently four people of working age supporting each pensioner in the UK, and this “dependency ratio” is expected to decrease significantly to 2:1 in the following 35 years (http://www.ons.gov.uk/ons/dcp171780_255969.pdf).
The longer life span does not necessarily equate to good health with almost three quarters of individuals aged 65 years and older predicted to have multiple chronic illnesses (http://mpkb.org/home/pathogenesis/epidemiology) . This is further supported by the rise in the prevalence of chronic diseases which has doubled within the last 20 years, and the proportion of people with four or more chronic diseases has increased by approximately 300 % in this period . Since chronic health conditions are a major cause of illness, disability, and death, this will lead to an increasing number of people who are most vulnerable to and most affected by chronic health conditions. Examples of common chronic diseases in the elderly include diabetes, hypertension, heart diseases, sensory deprivation (hearing and visual impairments), arthritis, and orthopedic problems, all known to require long-term healthcare and contribute to worsening of the physical and mental health of the older people, frequently resulting in confusion.