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The Link Between Infection and Decline In Cognitive Health

There have been various studies carried out into the relationship between infections and cognitive health, as the impact of inflammation and other changes on the brain can be quite considerable.


In this blog we look at the impact of infections for people living with dementia.


Why do infections have such a profound effect on cognitive health?

Infections can be either bacterial or viral. Viral infections are passed between people, for example, colds and flu. Bacterial infections are where bacteria enter a person via air, water, soil, or food causing illnesses such as ear infections, pneumonia or bronchitis. Essentially, an infection is when germs enter a person’s body and then multiply, resulting in the associated illness.


In healthy humans, the immune system responds to infection onset to protect against illness. Sometimes a person’s immune system may be weakened which can make it harder to fight infection.


As a person ages, the immune system also ages and response to infection may be weak and, in some cases, ineffective at preventing the infection from taking hold. This can then trigger an inflammatory response and it is this inflammation which can disrupt communication between cells, causing further cognitive decline.


Reducing the risk of infection for people living with dementia

There is increasing evidence of multiple potentially modifiable risk factors for developing dementia. Infection prevention is one of them and is something that everyone should be aware of.

Key areas to focus on are:

  • Immune System Following a healthy diet and exercising regularly can boost the immune system. It is also important to practice good hygiene and to stay up to date with immunisations (e.g. flu, pneumonia, COVID and shingles).

  • Urinary tract infections These can be common among the older population and also in people living with dementia. They can often be prevented by maintaining good perineal hygiene and by ensuring the person is adequately hydrated.

  • Oral infections – periodontitis People living with dementia are at risk of gum disease and tooth decay, often due to the person no longer managing their oral hygiene. This can be avoided through supporting the person with their oral hygiene routines and regular dental checks. Periodontitis is a bacterial, inflammatory gum infection which, if prevented, may lower the risk of further cognitive decline. The relationship between cognitive and oral health is two-way, as decline in one may cause the decline of the other.

  • Delirium Those diagnosed with dementia or cognitive impairment are at a high risk of developing infection-related delirium, which can result in further cognitive decline. It is important to try to prevent all delirium, including hospital-acquired delirium, by being alert to any new signs or symptoms of delirium and addressing them as soon as possible.


Consider the following when supporting a person with potential delirium:

  • Good sleep: It is very important that the person living with dementia has good sleep hygiene.

  • Environment: Ensure that the person is orientated and that any environmental factors that may add to confusion are addressed.

  • Social Stimulation: Maintain social and mental stimulation and ensure that all basic needs are met, minimising pain and discomfort.

  • Home recovery: If a person does develop delirium in hospital but is medically fit, recovering at home in their own environment would be the preferred option.


Get additional dementia support

If you need any further advice, you can get information, help and support on living well with dementia from our Wayfinders, even before a dementia diagnosis has taken place. Get in touch with a member of our Wayfinding team today.


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