Definition

Dementia is a syndrome characterized by a decline in cognitive function. This includes issues with thinking, memory, orientation, comprehension, calculation, language, learning capacity, and decision-making. The decline is chronic and progressively worsens over time. While cognitive decline can occur in older age, in dementia, this decline happens at a much faster rate. Currently, more than 55 million people worldwide suffer from dementia, and there are 10 million new cases each year. Dementia is the seventh leading cause of death globally and one of the major causes of disability and dependency among older adults.

Causes

Dementia is caused by various diseases and injuries that affect the brain. These conditions damage brain cells and the parts connecting the nerves, called synapses. Common types of dementia include Alzheimer's, vascular dementia, Lewy body dementia, frontotemporal dementia, and mixed dementia.

• Alzheimer's Dementia is the most common form, accounting for about 70-80% of all dementia cases. It can occur without a family history, although a family history is present in many cases. Alzheimer's is characterized by the buildup of beta-amyloid proteins forming plaques and tau proteins forming tangles in the brain's nerves, damaging healthy nerves and surrounding synapses.
• Vascular Dementia accounts for about 5-10% of all dementia cases. It results from damage to blood vessels supplying the brain, which can cause strokes or damage nerve fibres in the brain's white matter.
• Lewy Body Dementia accounts for about 5-10% of dementia cases. Lewy bodies are abnormal protein clumps shaped like balloons found in the brains of people with Lewy body dementia but can also be found in Alzheimer's and Parkinson's disease.
• Frontotemporal Dementia results from damage to nerves in the brain's front and side areas, affecting personality, behaviour, and language.
• Mixed Dementia Caused by a combination of the above factors.

Risk factor

The primary risk factor for dementia is old age, but it can also occur in younger individuals, under 65. Other risk factors include a sedentary lifestyle, smoking, excessive alcohol consumption, being overweight, an unhealthy diet, and high blood pressure, cholesterol, and blood sugar levels. Additional risks include depression, social isolation, low education levels, lack of mental activity, and air pollution.

Symptoms

Symptoms of dementia can vary depending on the type, severity, and the person's condition before dementia onset. Dementia is often divided into three stages: early, middle, and late.

• Early stage: Symptoms are often unrecognized and include forgetfulness, loss of time, and getting lost in familiar places.
• Middle stage: Symptoms become more apparent, such as forgetting recent events and names, confusion at home, communication difficulties, inability to care for oneself, and behavior changes like wandering and repetitive questioning.
• Late stage:  Dependency becomes clear, with symptoms like not recognizing time and place, difficulty recognizing family and friends, trouble walking, and severe behavior changes including aggression.

Certain symptoms are more frequent in specific types of dementia:

• Vascular Dementia: Balance issues, headaches, sensory and movement impairments, and speech difficulties.
• Lewy's Body Dementia: Visual hallucinations, delusions, sleep disturbances, and visual information processing problems. 
• Frontotemporal Dementia: Visual hallucinations, delusions, sleep disturbances, and visual information processing problems.

Diagnosis

Diagnosis of dementia involves several examinations, starting with a comprehensive physical and neurological assessment. Cognitive function tests may follow to evaluate various aspects of cognitive abilities, such as counting, speaking, remembering objects, and identifying the current time and place.

Neurological, psychological, dependency and behavioral assessments can also help evaluate cognitive function. The results can be used to adjust the patient's physical and social environment and reduce the risk of complications.

Laboratory tests, such as complete blood counts, urinalysis, lipid profiles, blood sugar levels, thyroid function tests, and syphilis tests, may also be performed. Imaging tests like magnetic resonance imaging (MRI) can visualize brain tissue conditions. Brain function imaging, such as positron emission tomography (PET) scans and functional MRI, though expensive and less commonly available, can also be used.

Management

Management of dementia aims to slow cognitive decline and alleviate emerging symptoms. Cognitive decline can be slowed with medications, while symptoms like irritability, anxiety, and depression can be treated with anti-anxiety or antidepressant medications. Psychological approaches, including environmental support, memory exercises, physical training programs, and mental and social stimulation, are also helpful.

If sleep disturbances occur, treatment may involve medication and non-drug approaches such as daily physical exercise, light therapy, sleep hygiene, avoiding alcohol and caffeine, pain control, and cognitive therapy with expert assistance.

For those with dementia or their families, seeking help from support groups like Alzheimer's groups is important for receiving support and sharing information about the disease, as dementia is long-term and progressively worsens. Those with dementia should also avoid driving.

Complications

Dementia affects not only cognitive function but also other aspects of the body and life. Complications can include nutritional deficiencies due to lack of appetite, pneumonia, dependency in self-care, safety risks, fractures from falls, hallucinations, delusions, apathy, agitation, difficulty swallowing, depression, urinary or bowel issues, personality changes, infections, and death.

Prevention

While there is no certain way to prevent dementia, the following measures can help:

• Keep your mind active: Mental stimulation, such as reading, solving puzzles, playing word games, and memory exercises, can delay dementia onset and reduce its effects.
• Stay physically and socially active: Physical and social activities can delay dementia. Aim for 150 minutes of physical activity per week, divided into several sessions over different days.
• Quit smoking:  Smoking increases the risk of dementia and vascular damage.
• Consume adequate vitamins: Vitamins such as B complex, C, and D are beneficial for brain and overall health.
• Maintain good circulation: If you have high blood pressure, diabetes, or high cholesterol, follow medication regimens and improve your diet. If overweight, aim to reach an ideal weight.
• Seek help for mental health conditions:  Address mood disorders like depression, bipolar disorder, or anxiety promptly.
• Ensure good sleep quality: Establish a sleep routine and create a conducive sleeping environment. Consult a doctor if you snore or have sleep disturbances.
• Address hearing issues: Hearing problems increase the risk of dementia, so managing these issues, such as using hearing aids, can reduce dementia risk.

When to see a doctor?

Consult a doctor if you or a family member exhibits symptoms of dementia, such as forgetfulness, communication difficulties, disorientation in time and place, problem-solving issues, planning difficulties, or movement control problems.