Does Dementia Run In Families?

If your loved one is having difficulty remembering information, recalling past events, problem solving or making judgements, you may be concerned that he or she is developing dementia.

Dementia is not a specific disease but a general term that describes the loss of cognitive functioning — thinking, remembering, and reasoning — to such an extent that it interferes with a person’s daily life. Some dementia patients cannot control their emotions and may experience personality changes.

Based on the nationwide “Well-being of Singapore Elderly” (WiSE study) , 1 in 10 seniors who are 60 years old and above, have dementia. Amongst those 85 years old and older, prevalence rates could be as high as one in two. As our population continues to age, it is estimated that there could be 130 000 or more Singaporeans living with dementia by 2030.

One of the greatest concerns for dementia patients and their families is whether the condition is inherited by future generations. To understand if dementia is genetic, we have to understand how genes work.


Genes and Dementia

Genes, which are found in the chromosomes, causes individuals to inherit characteristics like hair colour, height or the tendency to develop certain diseases. Some genes may directly cause someone to inherit a specific illness, which means the individual with that gene will certainly develop that disease. Other genes present a risk factor for certain diseases which means that these genes indicate whether the person is more or less likely to inherit the disease but does not cause him or her to develop that disease.

In the case of dementia, individuals with a family history are likely to have inherited genes that pose a higher risk for dementia. In addition, their chances of getting dementia also be influenced by health conditions, social factors and lifestyle choices.

Risk factors that affect dementia risk include age, cardiovascular diseases, diabetes, smoking, high alcohol intake, depression, poor diet and low levels of cognitive engagement.

Dementia that runs in the family

Alzheimer’s disease is the most common cause of dementia which affects 50 to 70 percent of all dementia patients. Apart from age, having a family history of Alzheimer’s disease increases the likelihood of one suffering from this disease in the future. Rare genetic mutations can also result in Alzheimer’s disease that occur even without a family history of dementia.

However, there is a rare form of Alzheimer’s disease, Early-onset Familial Alzheimer’s Disease (eFAD), that is unfortunately passed from generation to generation. If a parent has a mutated gene that causes eFAD, his or her child has a 50 percent chance of inheriting it. If the child inherits that gene, he or she will certainly develop Alzheimer’s disease, usually in their 30s to 50s. This form of Alzheimer’s disease only affects an extremely small number of people

Other forms of dementia such as vascular dementia – caused by strokes or issues with blood flow to the brain; dementia with Lewy bodies – caused abnormal deposits of a protein in the brain; and frontotemporal dementia – brain disorders that primarily affect the frontal and temporal lobes of the brain are also unlikely to be directly caused by genes.

Delaying and reversing dementia

There is currently no cure for dementia but medicines and treatments can help lessen dementia symptoms. However, there are ways to prevent or delay the onset of dementia.

According to a longitudinal study done in Singapore, published in JAMA Neurology in 2016, obesity, diabetes mellitus, hypertension and hyperlipidemia are associated with an increased risk of dementia.

As such, healthy choices and lifestyle changes since young may make a difference to dementia risk.

1. Eat Healthy

A diet rich in fruits, vegetables and omega-3 fatty acids commonly found in certain fish and nuts, may promote overall health and reduce dementia risk.

2. Exercise regularly

This makes the heart and blood circulatory system more efficient, lowers cholesterol and maintains blood pressure at a healthy level, decreasing the risk of developing vascular dementia.

3. Get sufficient sleep

Get at least 6 to 8 hours a night as lack of sleep can impair learning and memory. Studies suggest that poor sleep may be a risk factor for cognitive decline and Alzheimer’s dementia.

4. Socialise and keep your mind active

Social interaction and mentally stimulating activities, such picking up new skills, doing puzzles or playing word games may serve as cognitive training. 

Years before the symptoms of dementia become evident, the body may already be experiencing biological changes that make it more likely for someone to develop dementia – so it’s best to make recommended lifestyle changes early and sustain them over time.

For more information on Dementia Care, click here to learn more. 

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