The time of day you’re most likely to spot dementia – and the 5 signs to watch out for

MOST of us get tired, or at least a little cranky, as the day winds on.

But this is especially the case for those who have dementia, who may experience a change in behaviour in the late afternoon.

The condition, known as 'sundowning', can have a profound effect on those with mid- to late-stage dementia - but it can also be a a warning sign during the early stages.

Hilda Hayo, chief admiral nurse and CEO of , said 'sundowning' causes a person suffering from dementia to become agitated or anxious around dusk.

"They can often believe they are in the wrong place or need to do something urgently," she said.

"This can cause people to shout or become argumentative or restless and present challenges for the individual and their family or carers."

Figures show that up to 30 per cent of people living with the brain-robbing disease experience 'sundowning'. 

Unfortunately, there is little scientific evidence to explain its cause, which means it remains difficult to treat.

But most experts agree it's got something to do with people not getting enough sunlight in the winter afternoons and evenings.

"As darkness falls, streetlights come on, and people settle in for the evening," Hilda said.

"These changes can make the person increasingly concerned that they are in the wrong place or have forgotten to do something vital during the day."

Some studies suggests it could be caused by disturbances to the person's natural body clock, caused by damage to the brain.

Alternatively, it can sometimes be a side effect of prescribed medicines.

Sleep and eating schedules can also play a role.