Forgetfulness isn't the only sign of dementia. Behavioural changes – such as laughing at inappropriate things, loss of empathy, or compulsive checking – can also indicate a problem, especially in the early stages.
See also: People 'frequently misdiagnosed with common types of dementia'
"Some possible signs of dementia are harder to spot and may not seem so obviously related to the condition," says Kathryn Smith, Director of Operations at Alzheimer's Society. "Family members can often play a crucial role in the diagnostic process, so having an awareness of the signs and symptoms of dementia can ensure that people receive the appropriate diagnosis and support."
Here are eight hidden signs of dementia that could indicate a problem:
1. Warped sense of humour
Research shows that an increasingly warped sense of humour could be an early warning sign of a rare form of dementia. A study involving 48 patients with frontotemporal dementia (a leading cause of dementia in people under the age of 55) found that their families noticed a change in humour before their loved one's dementia was diagnosed.
Researchers at University College London asked relatives to rate their loved one's taste in comedy - slapstick such as Mr Bean, satirical comedy such as Yes, Minister or absurdist comedy such as Monty Python. They found many of the patients had developed a dark sense of humour, for example, laughing at tragic events in the news, and began to prefer slapstick to satirical comedy, up to nine years before they were diagnosed.
2. Frequent falling
People with dementia may become less steady walking and more prone to falls. Problems judging distances, on the stairs for example, and seeing objects in three dimensions, can also be an issue.
3. Loss of motivation
You may notice that they lose interest in the things they once enjoyed and were good at, no longer care about their appearance, withdraw from offering opinion, or generally seem less confident.
4. Loss of empathy
People with dementia can sometimes display a lack of empathy. Someone who used to be sympathetic may now say things that seem harsh or callous.
5. Not understanding embarrassment
They may lose their inhibitions and behave inappropriately in social situations, or not understand why their actions are a cause for embarrassment.
6. Compulsive or repetitive behaviours
Showing repetitive, compulsive or ritualised behaviours, which can include repeated use of phrases or gestures, or repeatedly asking the same question, can be a sign of dementia. Hoarding things and becoming obsessed with timekeeping can also be a sign
7. Different around food
A change in a person's attitude towards food can be another sign. Craving sweet or fatty foods, losing table etiquette or bingeing on junk food, for example.
8. Increasing difficulty in managing finance
People with dementia may have trouble managing their finances, in some cases becoming overtly frugal, in others spending large amounts. If someone has dementia they may get locked into a routine that makes no sense, such as buying the same item repetitively. Also bank security procedures and being able to remember passwords and pin numbers may become a real challenge.
While the points listed above do not necessarily mean your loved one has dementia, it's worth being aware of the less-common indicators.
Aside from the points above, you should seek medical advice if you notice problems with:
1). Day-to-day memory: repeated difficulty recalling events that happened recently.
2). Concentrating, planning or organising: difficulties making decisions, solving problems or carrying out a sequence of tasks (eg cooking a meal).
3). Language: repeated difficulties following a conversation or finding the right word for something.
4). Orientation: Becoming confused about where they are and losing track of days and dates.
Help and support
Alzheimer's Society encourages anyone who is worried about their memory or health to seek the support of their GP. Alzheimer's Society National Dementia Helpline provides a range of advice and support for people who are concerned, whether about themselves or someone else. To speak to an advisor call 0300 222 11 22 or visit alzheimers.org.uk. You can also download a Worried About Your Memory Booklet.