Experts say they have identified the tell-tale signs of dementia – with one describing the condition as a "time bomb" among the general population.
Researchers speaking to The Mirror say that improved life expectancy is also leading to a rise in the number of people with Alzheimer's or another form of the disease. More than one in 10 adults over the age of 65 have it in the US.
Dr Oscar Lopez, director of the University of Pittsburgh's Alheimer's Disease Research Centre, said: "One thing you need to emphasise is that the prevalence of dementia in general in the population is huge. It's a time bomb. Because people are living longer. From the neck down we're in really good shape. Because we can deal with heart problems very easily but the brain is still at risk of dementia. Especially Alzheimer's."
Symptoms
Dr Nicole Purcell, practising neurologist and senior director of clinical care at the Alzheimer's Association, says that while there is no "one-size fits all" sign that someone dementia, there are clear signs that can suggest if someone is deteriorating.
Changes to someone's personality, their ability to work and even difficulty walking can all be indicators of looming dementia. However, the most common agreed symptom of dementia is a loss of memory.
Dr Lopez said of the main signs: "Mainly forgetfulness. Or finding difficulties finding the right word. Normally people remember the word five to ten minutes after they forgot it but people with dementia most likely won't remember the word.
"Also people said 'I'm not the same, but I can not put that in words'. Or the family will say he or she is not the same person. They cannot put that in words. Sort of a feeling, that something is different."
He added: "Sometimes the disease starts with a personality change, they are more disinhibited, they are more aggressive."
Dr Purcell added of a diagnosis: "We generally recommend that if a patient is not functioning at their baseline whether it be psychiatric or behavioural symptoms. Maybe they're depressed when they've never had depression. Change in function. So they're having difficulty walking or they can't do the things they would normally do."
Dementia is an umbrella term for a number of cognitive disorders that impair the ability to remember, think, or make decisions. The majority of dementia patients have Alzheimer's but Parkinson's disease with dementia is also common. Frontotemporal dementia has been in the headlines recently due to Hollywood star Bruce Willis' diagnosis.
What can be done to prevent dementia
For decades little could be done to alleviate the symptoms of dementia but research has vastly improved in recent decades. New medicines are now coming onto the market which can slow cognitive decline in dementia patients. However, they are not widely accessible as yet. In the meantime, life-style changes can make a huge difference, our experts say.
Dr Purcell said: "We generally say what is good for the heart is good for the brain. So discontinuing any cigarette or alcohol use. Making sure blood pressure is controlled., diabetes is controlled."
She also emphasised staying socially and mentally active can help, adding: "Crosswords puzzles, learning something new or, I say, even just trying something you usually do in the day, try and do it differently. Social interaction also seems to be a significant risk factor that you can improve.
"So staying socially, physically and mentally engaged is incredibly important. The risk of dementia can be reduced around 40 percent if you make lifestyle changes mid life. It is a huge difference."
Anyone who is worried about themselves or a loved one can go to the Alzheimer Scotland website where there is a 24-hour, seven-days-a-week phone line where you can get advice and support. Dr Purcell said: "There is a fear factor. And there is a stigma factor but just get it checked."
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