Dementia is an umbrella term that describes a degenerative neurological disorder caused by diseases or injury to the brain. Although there are over 200 subtypes, there are four common types of dementia:

Weatherhead and Courtney ([280], p.114) state that ‘dementia is not a normal part of the ageing process, but almost all types of dementia are progressive and incurable’.

The WHO ([286]) estimates that over 50 million people are living with dementia worldwide, and this number is predicted to rise exponentially to 152 million people in 2050. The Alzheimer's Society ([8]) estimates that there were 850,000 people living with dementia in the UK in 2015, with a related cost of £26 billion a year.

Although the risk of developing dementia increases as people age, dementia does not exclusively affect older people. Although it is rare, and can be difficult to diagnose, dementia can affect younger people: 40,000 people aged under 65 have a dementia diagnosis in the UK (Alzheimer's Society [9]).

Dementia can be caused by a number of illnesses and manifests as a decline in multiple areas of functioning, most notably a person's ability to think, retain information, reason and communicate (Young Dementia UK [293]). People living with dementia are twice as likely to be hospitalized as people with normal cognitive functioning (Parke et al. [219]). Studies suggest that one‐quarter of UK inpatient beds were occupied by people with dementia in 2009 (Alzheimer's Society [7]), and that figure will have risen in the years since then.

Delirium and depression are prevalent in older patients, and it can be difficult to make a differential diagnosis between these presentations and dementia. Due to the differences in the treatments for these conditions, it is essential that healthcare professionals are able to identify key signs and symptoms associated with all three conditions so that appropriate management can be provided (Polson and Croy [225]).

De Vries ([58]) suggests that the ‘decline in communication ability for older people with dementia is usually progressive and gradual, with the condition affecting expressive and receptive language abilities’ (p.30). It is thought that those in the caring profession avoid communication with people who have dementia and this can have a negative impact on the person's experience and result in behaviour, which can be challenging (Jootun and McGhee [142]). People who have dementia frequently have word‐finding difficulties so supporting communication can include finding suitable tools, such as a communication book. The use of non‐verbal skills, such as simply allowing the person to point at what they want, can help in the communication process. It is important to engage with people with dementia and, although it may take more time, the results can be rewarding. Excluding or ignoring patients can leave them feeling frustrated and angry, therefore compromising their safety (Tonkins [269]).

The involvement of family and carers is important as they may have a greater understanding of the verbal and non‐verbal communication of the person with dementia. However, the involvement of family and carers should not exclude communication between the person with dementia and nurses; the person with dementia should be involved as much as possible in all communication relating to their care. As Jootun and McGhee ([142], p.41) suggest, it is important for nurses to demonstrate sensitivity and encourage the person to communicate in the way they are most able and prefer.

Baillie et al. ([15]) suggest that providing personal care to a person with dementia, if done sensitively, can help to develop the relationship between them and the nurse. However, it is important to consider what the person with dementia might be experiencing as their reality may not be the same as the nurse's. For example, the person with dementia may think they are at home and that the nurse is a family member.

There is a higher risk for patients with cognitive impairment (compared to those who do not have cognitive impairment) who are admitted into a hospital to have poorer health outcomes and be discharged into 24‐hour care. NICE ([211]) recommends that care plans for patients with dementia should promote and maintain the patient's independence in activities of daily living (such as mobility and personal care) due to the high risk of institutionalization and dependency on others. When writing care plans, the unique needs of people with dementia must be taken into consideration and addressed to ensure person‐centred care. Environmental factors, such as signage and a clear, clutter‐free bed space, should always be considered to ensure safety and promote independence (RCOT [235]).

The principles of the Mental Capacity Act ([176]) apply to all patients and the first principle of the act, the presumption of capacity, also applies to patients who have dementia. A person's capacity is decision specific and, as such, a person with dementia should have the ability to make decisions as long as they can show that they understand the decision they are making and the risks associated with that decision. If a patient with dementia declines care or treatment, they should be treated as an adult with capacity unless an assessment of capacity has indicated they lack capacity to make the decision. If this is the case, a best interest decision must be made in consultation with the patient's family. Where the person has no family and the decision relates to medical treatment or about where they will be living, a referral must be made to the Independent Mental Capacity Advocate.

For people with dementia who are in hospital or a care setting, consideration needs to be given to the Deprivation of Liberty Safeguards (DoLS). If a patient is unable to consent to being in hospital and there are restrictions on their liberty, they are not free to leave if they wish to, so they may be being deprived of their liberty.