What Causes Dementia?

More than just typical forgetfulness, dementia is the loss of brain function that causes rapid memory loss, impaired cognition (thinking ability), intellectual and physical malfunction and personality change.

According to Dr Norhisham Main, Senior Consultant, Geriatric Medicine & Palliative Medicine, Ng Teng Fong General Hospital, the disease had a prevalence of 26.6 million worldwide in 2006 and has almost doubled in under a decade, to 44.4 million in 2013. Some estimates show that numbers are set to grow to 75.6 million in 2030.

“In Singapore, some 30,000 were recorded to have dementia in 2010 and numbers may triple to 92,000 in 2030,” he said.

While the disease is often associated with the elderly, it is also striking a younger population as well. The National Neuroscience Institute records show that 45 percent of their patients with dementia are below 65 years.

Dementia has a profound impact not only on the afflicted but also on the lives of those around them. People with dementia have a high chance of deteriorating rapidly if they are undiagnosed. This is why awareness, early diagnosis and intervention are important to better manage the condition.

Related: Understanding Dementia

The Root Causes

 A daughter comforting her father as his dementia progresses.

Dementia is not actually a disease in itself, but a collection of symptoms that are caused by several diseases. The most common form of dementia is Alzheimer’s disease, which makes up about 7 in 10 cases of dementia.

Vascular dementia is another type that is caused by a series of small strokes.

Other less common types of dementia include frontotemporal dementia and Lewy body dementia, which have the same effect of causing brain cells to die at a faster rate than is normal.

Related: Reduce Your Risk of Developing Dementia

Diagnosing Dementia

Dementia is caused by damage to or loss of nerve cells and their connections in the brain.

Dementia is not a normal part of ageing. Telling the difference between the normal forgetfulness of old age and dementia takes a comprehensive assessment by a medical doctor and sometimes, a psychologist. Blood tests may be used to look for underlying disease conditions or other abnormalities. Brain imaging tests may also be ordered to look for structural changes caused by tumours or stroke. A psychologist will also be able to confirm dementia using a series of questions that assess the different aspects of brain function.

Related: How to Cope When a Parent Has Young Onset Dementia

Stages of Dementia

text: A daughter advising her mother on the various stages of Alzheimer’s disease.

Stage 1: No impairment

Stage 2: Mild cognitive decline with mild memory lapses—forgetting familiar words or misplacing everyday objects

Stage 3: Mild cognitive decline with detectable lapses in memory such as trouble remembering names of people one has just met or forgetting content that one has just read

Stage 4: Moderate cognitive decline with more severe forgetfulness—inability to recall recent events; do challenging mental maths (eg, counting backwards in multiples of 7); manage personal finances or plan a dinner

Stage 5: Moderate or mid-stage disease with noticeable gaps in memory such as being unable to recall one’s home address or telephone; confusion about where one is or what day it is

Stage 6: Moderately severe or mid-stage disease with worsening memory, personality changes and inability to do daily activities. There may be a loss of awareness about surroundings or difficulty with remembering personal details or the name of a spouse or caregiver as dementia progresses.

Stage 7: Severe cognitive decline and inability to hold a conversation, control movement or even swallow

Related: Dementia Role Reversal: Who Is the Caregiver Now

Warning Signs of Dementia

Proper care plans must be put in place for both caregivers and people with dementia.

More than simple forgetfulness, signs of dementia include:

  • Memory loss, particularly of short-term events. Examples include not remembering what one just ate or why one entered a room. A person may also no longer recognise a familiar face or place
  • Difficulty communicating simple thoughts or wants
  • Mood changes, depression or shifts in personality
  • Loss of ability to do familiar tasks and chores
  • Confusion and disorientation - One may get lost in a familiar neighbourhood as the disease progresses

Related: My Loved One Has Dementia—What Do I Do?

Old Age Forgetfulness or Dementia?

An elderly couple with dementia in wheelchairs taking time to enjoy the park.

Forgetfulness can occur in an older person without dementia. This is normal and a part of the ageing process. Typically, ‘normal’ forgetfulness is due to a distraction or if one is multi-tasking. Given enough time, a person will recall the forgotten item or event. In terms of learning, an older person will also be able to do a task or learn a skill just as well as a younger person if given enough time. In contrast, said Dr Main, dementia causes abnormal lapses in memory and behaviour.

“Persons with dementia are unable to recall or remember information that has been given even after prompting or when given time. They may behave inappropriately or perform tasks that are beyond reason like putting laundry in the refrigerator.”

With the prevalence of dementia expected to rise, early diagnosis and intervention will help manage the challenges that a person with dementia faces and allow for advance care planning. Social support and community-based care are also essential to help caregivers cope.

Related: Warning Signs of Dementia

Caring Well for Dementia

A person with dementia with Lewy bodies in the hospital getting advice from a doctor.

To ensure that a person with dementia gets the best care that he or she prefers, early diagnosis, intervention and advance care planning are important. This is to put care plans in place while the individual can make his or her own decisions and before the loss of mental capacity.

“The management of dementia involves a multi-disciplinary approach that uses both drug and non-drug measures,” explained Dr Main. Some drugs, collectively known as cognitive enhancers, may be useful in helping to maintain memory, thinking and speaking skills.

These treatments should not be used in isolation but to complement other non-drug measures such as music therapy, art therapy, massage therapy, reminiscence therapy and structured exercise programmes to minimise the behavioural and psychological symptoms of dementia.

One successful approach is ‘person-centred care’, Dr Main noted, an approach that places the person with dementia at the centre of care and acknowledges the important role of the caregivers.

Related: Managing Wandering Behaviour in Dementia

Help for Caregivers

Caregivers of people with dementia need to look after their own mental health too.

Dementia also takes its toll on caregivers, who may suffer from mental and physical exhaustion due to the demands of looking after a person with dementia. Taking care of caregivers—via respite care, day centres and other support services—is important. For instance, respite care allows caregivers to take time away and recharge.

Preventative Steps

Eating a balanced diet can help delay or prevent the onset of dementia.

No one knows what causes Alzheimer’s disease, the most common type of dementia, but a ‘brain-healthy’ lifestyle may help delay or prevent the onset of the disease.

This means regular exercise, eating a balanced diet, moderating alcohol consumption, light mental stimulation (doing crossword puzzles, playing chess or mahjong, learning a new language), social interaction and stress management.

When Memories Fade (PDF).

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