According to the NHS, neurodegenerativeÂ condition Alzheimer's disease is estimated to affect around 850,000 people in the UK.
The husband of former Eastenders star Dame Barbara Windsor recently revealed that the actor was officially diagnosed with Alzheimer's in 2014, but her symptoms have worsened in recent weeks.
Windsor's husband, Scott Mitchell, first noticed signs of the condition as early as 2009 - but what exactly should we all be looking out for in the behaviour of our loved ones?
What are the early symptoms?
As it is a progressive condition, the symptoms of Alzheimer's develop gradually and become more obvious over the course of several years.
The first obvious sign of Alzheimer's tends to be minor issues with memory, such as forgetting recent conversations, or the names of places and objects.
As the condition worsens, the NHS advise that common symptoms can include:
confusion, disorientation and getting lost in familiar placesdifficulty planning or making decisionsproblems with speech and languageproblems moving around without assistance or performing self-care taskspersonality changes, such as becoming aggressive, demanding and suspicious of othershallucinations (seeing or hearing things that aren't there) and delusions (believing things that are untrue)low mood or anxiety
Who is at risk of developingÂ Alzheimer's disease?
Generally, people over the age of 65 are at higher risk of presenting signs of Alzheimer's, but anyone with a family history of the illness or who has suffered severe head injuries in the past could also develop symptoms.
Around 850,000 people in the UK are thought to be affected by Alzheimer's disease (Photo: Shutterstock)
Those with lifestyle factors and conditions associated with cardiovascular disease can also be at risk.
Women are slightly more likely than men to be diagnosed with Alzheimer's disease.
Are elderly people the only ones at risk?
While they are most commonly diagnosed, the disease is not exclusively found in the over 65s. In fact, around one in every 20 cases of Alzheimer's disease affects people aged between 40 and 65.
What should I do if I think I have or someone I know has Alzheimer's?
If you are concerned about your own memory or that of a family member or friend, the best course of action is to speak to a GP about it.
There is currently no cure for Alzheimer's disease, though there are some medications available to treat symptoms (Photo: Shutterstock)
There is no single test that can be used to diagnose Alzheimer's disease. The doctor will ask questions about any memory issues, and may do some tests to rule out other conditions.
Is there a cure?
There is currently no known cure for Alzheimer's, although there are some medications that can ease some of the symptoms and slow down the progression of the condition in some people.
On average, people with Alzheimer's disease live for around 8 to 10 years after they start to develop symptoms.
How can I preventÂ Alzheimer's?
Since the exact cause ofÂ Alzheimer's is not currently known, there is no surefire way to prevent the disease.
However, it may be possible to reduce or delay your risk of developing dementia by living a healthy lifestyle. The NHS recommend quitting smoking and cutting down on alcohol, eating a healthy diet and staying physically fit and mentally active.
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