A new study suggests that people in middle-age who frequently suffer from dizzy spells (orthostatic hypotension) are 40% more likely to develop dementia later on in their lives.

[Read more: What it really feels like to suffer from dementia]

The study of 11,000 people by the Johns Hopkins Bloomberg School of Public Health in the US found that sudden drops in blood pressure – which cause dizziness – can lead to permanent damage to the brain, boosting chances of dementia in the process.

So, aside from bouts of dizziness, what other early signs of dementia should you be aware of?

1. Being repetitive

Has someone asked you the same question several times during one conversation? Or told you the same biographical detail every time you’ve met? Or have they begun to repeat daily tasks unnecessarily, like making the bed or brushing their teeth? They could be showing signs of dementia.

2. Loss of sense of direction

Losing your sense of direction and spatial awareness is common in dementia patients, who often end up being unable to recognise landmarks, and things like the way home, or which house they live in.

3. Listlessness

Feeling apathetic about spending time with the people you love, or hobbies and activities that you’ve always been interested in doing, can indicate the onset of dementia.

[Read more: 11 things you should really know about dementia]

4. Short-term memory struggles

Being able to vividly remember events from decades ago, but struggling to remember what you had for lunch, can be an early sign of dementia. As can regularly forgetting why you entered a room, or where you left your keys (although these are not sure-fire signs of dementia, as of course, we all lose our keys from time to time).

5. Trouble following stories

If someone is struggling to follow the plot of a programme they usually enjoy, or can’t recognise how a film has been developing, they may be exhibiting dementia-like symptoms.

6. Communication and confusion

Showing signs of confusion – from forgetting faces and names of people you know well, to regularly misplacing things – may indicate the early stages of dementia. Communication issues are also a key problem, so a potential sufferer could find it difficult to think of the right word to use in a sentence, or are unable to verbally express how they are feeling or thinking, which can be very frustrating.

7. Mood swings

Dementia can affect a person’s ability to judge a situation, so someone who might usually be considered a wallflower, may suddenly start behaving in a much more outgoing, in-your-face way, while depression can also be a key early sign of the condition.