Dementia is not a single disease in itself, but a general term to describe symptoms such as impairments to memory, communication and thinking.
While the likelihood of having dementia increases with age, it is not a normal part of aging. Before we had today’s understanding of specific disorders, “going senile” used to be a common phrase for dementia (“senility”), which misunderstood it as a standard part of getting old.
Light cognitive impairments, by contrast, such as poorer short-term memory, can happen as a normal part of aging (we slowly start to lose brain cells as we age beyond our 20s3). This is known as age-related cognitive decline, not dementia, because it does not cause the person or the people around them any problems.1 Dementia describes two or more types of symptom that are severe enough to affect daily activities.
Symptoms that are classed as “mild cognitive impairment” – which, unlike cognitive decline, are not a normal part of aging – do not qualify as dementia either, since these symptoms are not severe enough.1 For some people though, this milder disease leads to dementia later on.
An analysis of the most recent census estimates that 4.7 million people aged 65 years or older in the US were living with Alzheimer’s disease in 2010.5 The Alzheimer’s Association has used this analysis to number-crunch the extent of the disorder in its 2013 report. It estimates that:
Just over a tenth of people aged 65 years or more have Alzheimer’s disease.
This proportion rises to about a third of people aged 85 and older.
The non-profit organization says Alzheimer’s accounts for between 60% and 80% of all cases of dementia, with vascular dementia caused by stroke being the second most common type.
Signs and symptoms
Memory loss in dementia can be serious enough for the person to forget where they are, even on their home street.
The symptoms of dementia experienced by patients, or noticed by people close to them, are exactly the same signs that healthcare professionals look for. Therefore, detailed information on these is given in the next section about tests and diagnosis.
A person with dementia may show any of the following problems, mostly due to memory loss – some of which they may notice (or become frustrated with) themselves, while others may only be picked up by carers or healthcare workers as a cause for concern. The signs used to compile this list are published by the American Academy of Family Physicians (AAFP) in the journal American Family Physician:6
Recent memory loss – a sign of this might be asking the same question repeatedly, forgetting about already asking it.
Difficulty completing familiar tasks – for example, making a drink or cooking a meal, but forgetting and leaving it.
Problems communicating – difficulty with language by forgetting simple words or using the wrong ones.
Disorientation – with time and place, getting lost on a previously familiar street close to home, for example, and forgetting how they got there or would get home again.
Poor judgment – the AAFP says: “Even a well person might get distracted and forget to watch a child for a little while. People with dementia, however, might forget all about the child and just leave the house for the day.”
Problems with abstract thinking – for example, dealing with money.
Misplacing things – including putting them in the wrong places and forgetting about doing this.
Mood changes – unlike those we all have, swinging quickly through a set of moods.
Personality changes – becoming irritable, suspicious or fearful, for example.
Loss of initiative – showing less interest in starting something or going somewhere.
Treatment of dementia: depends on its cause. In the case of most progressive dementias, including Alzheimer’s disease, currently their is no cure and no treatment that could stop its progression. But there are drug treatments that may temporarily improve symptoms. The same medications used to treat Alzheimer’s are among the drugs sometimes prescribed to help with symptoms of other types of dementias. Non-drug therapies can also alleviate some symptoms of dementia.
research is currently going on to configure an effective treatment for dememtia.
Dementia’s risk and prevention
Some risk factors for dementia, such as age and genetics, cannot be changed. But researchers continue to explore the impact of other risk factors on brain health and prevention of dementia. Some of the most active areas of research in risk reduction and prevention include cardiovascular factors, physical fitness, and diet.
Cardiovascular risk factors: Your brain is nourished by one of your body’s richest networks of blood vessels. Anything that damages blood vessels anywhere in your body can damage blood vessels in your brain, depriving brain cells of vital food and oxygen. Blood vessel changes in the brain are linked to vascular dementia. They often are present along with changes caused by other types of dementia, including Alzheimer’s disease and dementia with Lewy bodies. These changes may interact to cause faster decline or make impairments more severe. You can help protect your brain with some of the same strategies that protect your heart – don’t smoke; take steps to keep your blood pressure, cholesterol and blood sugar within recommended limits; and maintain a healthy weight.
Physical exercise: Regular physical exercise may help lower the risk of some types of dementia. Evidence suggests exercise may directly benefit brain cells by increasing blood and oxygen flow to the brain.
Diet: What you eat may have its greatest impact on brain health through its effect on heart health. The best current evidence suggests that heart-healthy eating patterns, such as the Mediterranean diet, also may help protect the brain. A Mediterranean diet includes relatively little red meat and emphasizes whole grains, fruits and vegetables, fish and shellfish, and nuts, olive oil and other healthy fats.