Dementia in women: Why being female puts you at higher risk of getting this debilitating illness

When it comes to dementia, studies around the world show that women are more prone to getting this neurodegenerative condition than men.
Dementia is a general term used to describe symptoms that affect memory, thinking and social abilities to the extent that it interferes with a person’s daily activities, said neurologist Dr Zhao Yi Jing.
According to the Institute of Mental Health’s nationwide Well-being of the Singapore Elderly (WiSE) study, dementia affects one in 10 people aged 60 and above.
“Dementia is not a specific disease, but rather a syndrome that can be caused by many different underlying conditions,” said Dr Zhao, who is medical director of Zhao Neurology and Headache Clinic.
When a person has dementia, forgetfulness is not the only sign. Said Dr Jennifer Hung from the division of neurology at the National University Hospital (NUH): “[Dementia] affects judgement, comprehension, visuospatial awareness (the way a person relates visual information to the space around them), learning capacity, language and thinking.”
DIFFERENT TYPES OF DEMENTIA
The most common type of dementia – and the type that women are more susceptible to – is Alzheimer’s disease.
“Women are twice more likely to develop Alzheimer’s dementia compared with men,” said Dr Rana Aroos, a consultant at the division of geriatric medicine at Alexandra Hospital.
In Alzheimer’s disease, an accumulation of abnormal proteins in the brain leads to the death of brain cells and then, the gradual loss of brain function.
The exact cause is not fully understood, although Dr Zhao said: “It is believed to involve a combination of genetic, environmental and lifestyle factors.”
Alzheimer’s disease tends to affect those above 60 years and accounts for 60 to 70 per cent of dementia cases, said Dr Hung. “Eventually, patients may have memory loss so severe that it results in the loss of communication and motor skills, resulting in total dependence on others for their everyday activities.”
Besides Alzheimer’s disease, other types of dementia include vascular dementia, often a result of a stroke, and Parkinson’s disease, which affects the nervous system and parts of the body controlled by the nerves.
Less common forms of dementia include Lewy body dementia, which affects thinking, memory and movement. Another type, frontotemporal dementia, affects the frontal and temporal lobes of the brain and can lead to changes in personality, language ability and movement.
DEMENTIA RISK: A LONGER LIFESPAN AND MENOPAUSE
“Age is one of the biggest risk factors contributing to dementia”, said Dr Hung. As women tend to live longer, we’re likely to reach the age where the dementia risk is higher.
Dr Zhao added that the decline of oestrogen levels during menopause is also a risk factor. These hormonal changes may contribute to the process that leads to Alzheimer’s disease.
Furthermore, the risk of cardiovascular disease increases in women post-menopause, which can also raise the risk of dementia, said Dr Chan Wan Xian, a cardiologist at Mount Elizabeth Hospital.
DEMENTIA RISK: HEART DISEASE, HYPERTENSION AND DIABETES
Dr Chan said cardiovascular disease, which is the most common cause of death among women in Singapore, also increases their risk of dementia.
A long-term study published in the Journal of the American Heart Association in 2013 found that female heart attack survivors were twice as likely to experience a decline in memory and cognition.
“Heart failure may lead to cognitive decline due to dysfunction in the brain neurons, thereby causing neurodegeneration,” she said. “Atrial fibrillation can cause small blood clots that can block the small arteries supplying blood to the brain, which can lead to poor circulation to the brain or even cause a stroke,” said Dr Chan.
The result of all these, she added, can lead to cognitive decline and dementia in the long term.
Arteriosclerosis also contributes to an increased risk of developing Alzheimer’s disease, said Dr Zhao. This type of cardiovascular disease involves the hardening and loss of elasticity of the small arteries, and is linked to hypertension and diabetes – and women are more prone to getting severe arteriosclerosis.
Besides cardiovascular disease, Dr Chan said those with hypertension and diabetes are also at an increased risk of dementia. The conditions damage the blood vessels throughout the body, including the blood vessels in the brain.
“Damage to the blood vessels and chronic inflammation can reduce blood flow and oxygen delivery in the blood vessels, which can contribute to an increased cognitive impairment,” said Dr Hung.
DEMENTIA RISK: POOR SLEEP AND MENTAL HEALTH
Many women tend to have poorer quality of sleep and shorter sleep duration due to their multiple social roles – wife, mother, daughter and colleague – as well as gender-based responsibilities, such as being the main caregiver in the family.
Mount Elizabeth Hospital’s Dr Chan said a lack of sleep together with emotional stress have been shown to increase dementia risk.
Moreover, depression and anxiety, two mental health disorders that are more common in women than men, are known contributors, and increase the risk of, cognitive decline, said NUH’s Dr Hung.
DEMENTIA RISK: ETHNICITY HAS A ROLE TO PLAY
While not gender specific, local studies have shown that Malays and Indians have a higher likelihood of being afflicted with Alzheimer’s disease than the Chinese, said Alexandra Hospital’s Dr Aroos.
A 2010 study using population-based data from the 2003 Singapore National Mental Health Survey of the Elderly found that the overall prevalence rate of dementia among Malays and Indians was 9.4 and 8.8 per cent respectively, compared with 4.2 per cent for the Chinese.
EARLY SIGNS OF DEMENTIA 
Doctors say some degree of forgetfulness is part of ageing but you should seek help when it starts to affect your ability to function. Short-term memory loss is often an early sign of dementia.
The early signs of dementia generally involve changes in cognitive abilities, said NUH Dr Hung. As the disease advances, more symptoms may emerge, including difficulty with planning or problem-solving, changes in personality and mood, confusion or disorientation about time and place.
Other early symptoms, according to Dr Aroos from Alexandra Hospital, include:
A HEALTHY LIFESTYLE CAN HELP REDUCE DEMENTIA RISK
There is no guarantee when it comes to dementia prevention. However, as dementia has many causes and risk factors, including cardiovascular disease, both Drs Chan and Hung advised living a heart-healthy lifestyle to reduce the causes.
This includes eating a balanced diet – one that is rich in fruits and vegetables, moderate amounts of fish and white meat, and wholegrains. And limit your intake of sugary and processed foods.
Get regular exercise too. “Aim for at least 300 minutes of moderate-intensity aerobic activity, such as brisk walking, swimming or cycling, per week, along with strength-training exercises twice a week,” said Dr Hung.   
Don’t forget adequate rest and sleep – it can help decrease cardiovascular disease and dementia associated with vascular causes, added Dr Chan.
More importantly, keep to your regular health checks as early detection and intervention can make a significant difference in managing symptoms and planning for the future, said Dr Hung. 
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