Dementia is an umbrella term used to describe a decline in mental function. It can affect memory, language, problem-solving, judgment, social interactions, and other mental abilities, interfering with daily life. Dementia is not a specific disease, so its treatment depends on the underlying cause.
What is dementia?
Dementia is a condition where a drop in mental (cognitive) function occurs, which can be caused by various illnesses or injuries affecting the brain. The impairment can vary from mild to severe and might even cause personality changes. Dementia is generally a progressive syndrome, and the rate of deterioration will vary from person to person.
The most common symptoms are memory loss, disturbances in processing thoughts or finding words, difficulty in problem-solving and reasoning, confusion, disorientation, and difficulty with coordination and balance. As the disease progresses, patients may experience an inability to recognize everyday objects and perform previously familiar tasks.
Although dementia primarily occurs in those over 65 years, it sometimes occurs in younger people. For example, early-onset (or young-onset) dementia patients can show symptoms as early as age 30, which often manifests similarly to other forms of dementia.
Types of dementia
Dementia is a term used to describe a set of several symptoms. There are several subtypes of dementia, including:
Alzheimer’s Disease is the most commonly associated with dementia, and it is the most common cause. It is characterized by a decline in memory, thinking, and reasoning skills. Alzheimer’s occurs through the appearance of abnormal protein deposits (called plaques, which once accumulated become tangles) in the brain that damage healthy brain cells. This disease also causes the frontal and temporal lobes of the brain to shrink. According to the National Institute on Aging, Alzheimer’s disease is the seventh leading cause of death among all adults in the United States.
Vascular Dementia occurs when the vessels that provide blood supply to the brain are damaged. The common signs of dementia are more noticeable than memory loss in the early stages: difficulty solving problems, slowed thinking, and loss of focus and organization. However, memory loss does develop in late-stage vascular dementia.
Lewy Body Dementia is characterized by balloon-like clumps of proteins in the brain. The common signs of this type of dementia are acting out one’s dreams in sleep, seeing things that aren’t there, problems with focus and attention, and uncoordinated, slow movements. They may also experience tremors and rigidity, which occurs in Parkinson’s disease and possibly in late stage Alzheimer’s. .
Frontotemporal Dementia patients suffer from a breakdown in nerve cells and their connections in their brains’ frontal and temporal lobes. The common signs affect behavior, personality, thinking, judgment, language and movement.
Mixed Dementia is often found in patients over 80 years old. As the name implies, these patients suffer from different types of dementia damage at once.
Symptoms of dementia
Symptoms of dementia can be divided into cognitive and psychological signs. At first, memory loss might be subtle, but it eventually reaches a stage where loved ones or co-workers will notice. As a result, finding words and communicating will be difficult, and patients will develop problems with navigating familiar areas, e.g. getting lost while driving.
Problem-solving and reasoning become more of a challenge, as do handling complex tasks, including planning and organization. In more advanced stages, there is a loss of coordination and difficulty with motor tasks. Other typical symptoms are confusion and disorientation.
A psychological symptom of dementia is a personality change, e.g., someone who is usually gentle becomes aggressive. Other symptoms include depression, anxiety, inappropriate behavior, paranoia, agitation, and visual hallucinations.
Stages of dementia
Cognitive impairment in dementia does not happen all at once. Health professionals describe the level of decline in the patient as a ‘stage’. The Global Deterioration Scale (GDS) is a tool used by doctors to assess the severity of primary degenerative dementia, such as Alzheimer’s disease. The scale consists of seven stages, each associated with different symptoms. 
Stage one is characterized by no cognitive decline, but in stage two, patients may experience mild decline, such as forgetting familiar names or words. Patients may experience memory loss, disorientation, difficulty with complex tasks, and personality changes as the disease progresses. In the final stage, patients may be entirely dependent on others for care and may lose the ability to communicate. The GDS is an essential tool for clinicians in determining the best course of treatment for patients with dementia.
No cognitive decline
No significant memory problems or any cognitive impairment.
Very mild cognitive decline
Forgetting familiar names and misplacing objects.
Mild cognitive decline
Increased forgetfulness, difficulty finding words, and slight difficulty concentrating. Starts to get lost. Loved ones begin to notice.
Moderate cognitive decline
Forgets recent events and has increased difficulty concentrating, difficulty to complete tasks. May be in denial of symptoms. May withdraw from friends and family.
Moderately severe cognitive decline
Major memory difficulty. Forgets details such as address and phone number. Needs assistance with daily functions, as they rely on others for survival.
Severe cognitive decline
Cannot carry out daily functions without help. Forgets names of family members and recent events. Forgets significant events of the past. Difficulty speaking. Delusions, compulsions, and anxiety increase. May experience urinary and fecal incontinence. Personality changes may occur at this stage.
Very severe cognitive decline
Requires help with most activities. Cannot speak or communicate more than a few words, eventually losing all verbal ability. Loses ability to walk, sit up, smile, and hold head up.
Diagnosing dementia may be challenging since healthcare professionals must recognize a pattern of loss of skills and function and determine what the patient is still able to do. This will include taking a medical history and asking someone close to the patient about symptoms.
No single test can diagnose dementia, although recent findings show biomarkers (a measurable indicator in the body) may help diagnose Alzheimer’s disease. Other tests include:
- Cognitive and neuropsychological tests: measure thinking skills such as memory, orientation, reasoning, language skills, and attention
- Neurological evaluation: an assessment of visual perception, attention, balance, reflexes, memory and other areas.
- Brain scans: CT, MRI, and PET scans: to detect any bleeding, evidence of stroke, or presence of tumors and examine the patterns of brain activity
- Lab tests: blood tests to detect underlying causes such as deficiencies, inflammation, or infection.
- Psychiatric evaluation: to understand the mental health condition
A reliable informant such as a spouse or family member might need to accompany the patient to these visits to provide a history of any incidents or complaints. An evaluation of the patient’s safety (e.g. should they still be using appliances or managing finances?) and their quality of life will also be conducted.
Causes of dementia
Dementia occurs when damage to or loss of nerve cells and their connections occurs in the brain. The symptoms and the effects seen in the patient depend on the extent of the damage to the area affected by it.
Dementias are grouped according to the factors they have in common, e.g., the type of protein/s deposited in the brain and the area of the brain involved in these changes.
Risk factors include
- family history
- lack of exercise
- unhealthy diet
- excessive alcohol use
- air pollution
- sleep disruptions
- nutritional deficiencies, and
- the use of certain medications (e.g., diphenhydramine and oxybutynin)
Certain conditions also increase the risk of developing a dementia-related disease:
- heart problems/risks
- head trauma
- Down Syndrome
- Huntington’s Disease
- Creutfeldt-Jakob Disease, and
- Parkinson’s Disease
Reversible dementia-like conditions can occur with infections, immune disorders, metabolic problems, nutritional deficiencies, hormonal abnormalities, and medication side effects. Anything causing pressure in the brain, such as a tumor or abnormal buildup of cerebrospinal fluid, can have the same result. In these cases, dementia will improve once the cause is treated.
Prevention of dementia
While there is no sure way to prevent dementia and related conditions, there are ways to decrease the chance of it occurring. One way is to reduce the controllable risk factors associated with the development of dementia. For example, quitting cigarettes and avoiding excessive use of alcohol are two lifestyle changes that decrease risk.
Mental stimulation is vital, as are physical activity, socializing, maintaining a healthy diet, and getting good quality sleep.
Underlying health conditions can be additional threats. Obesity and cardiovascular problems such as high blood pressure should be managed as these also pose a risk. Likewise, depression and anxiety should be treated as needed. Those with hearing problems should get the best possible hearing aids as lack of hearing can contribute to cognitive decline. The same applies to those with vision problems. Disorientation due to a lack of sensory aids can cause someone to present as if they have dementia.
Treatment for dementia
While most types of dementia cannot be cured, it is possible for symptoms to be managed and the progression of the disease slowed down. Medications can temporarily improve the decline in cognitive ability:
- Cholinesterase inhibitors, e.g., donepezil (Aricept), rivastigmine (Exelon), and galantime (Razadyne), are used primarily in Alzheimer’s but also in other dementias. They act by preventing the breakdown of acetylcholine, a key chemical messenger involved in memory and judgment.
- Memantine regulates the activity of glutamate, a chemical messenger that controls learning and memory.
Cholinesterase inhibitors and memantine are sometimes also prescribed together. Depression, sleep problems, hallucinations, parkinsonism, or agitation are also treated with appropriate medication.
Occupational therapy helps the patient or caregiver make the home safer to prevent accidents and teaches practical coping mechanisms, e.g., reducing clutter to help focus. Physical therapy can assist with motor changes that impact gait and movement. Psychotherapy prepares patients and caregivers for the progression of dementia.
Self-care for dementia
If you have been diagnosed with dementia, there are things you can do to slow its progression and improve your quality of life. For example, self-care actions maintain independence, improve self-satisfaction, and increase safety while reducing the need for assistance from others.
Your doctor will need to evaluate your degree of mental decline periodically to make sure you stay safe if you are living alone or with a caregiver. Plan for the future. Identify a caregiver and other family/friends who might be able to help or make care home arrangements for when the disease progresses.
Light exercise improves strength, balance, and heart health. Such practices might slow down the progression of impaired thinking in those with Alzheimer’s and can lessen the symptoms of depression. 
Stay organized. This includes placing reminders where you can spot them, calendars to remember appointments and daily activities, and a pill organizer to stay on top of your medication schedule.
A dementia diagnosis does not mean you have to stop being you!
- Join a support group of those going through the same thing as you and build community.
- Engage in social activities and keep the mind active (both activities are of utmost importance for connection and maintaining focus)
- Keep having fun and connecting with loved ones!
Helping someone with dementia
Caregivers are lifelines for those suffering from dementia. Often this comes with great sacrifice as well as emotional and financial burden. Caregivers must recognize the crucial aspect of also caring for themselves and finding relief with help from additional resources. Understanding the condition of the patient is the first step in being able to care for someone with dementia.
Further to that, some activities will improve the quality of care and the patient’s quality of life.
- Enhance communication by maintaining eye contact, not rushing, and speaking in simple sentences. Try to present one idea at a time. For more guidance on communication, read our article on how to talk to someone with dementia.
- Encourage light exercise and movement if this is safe for the patient.
- Engage in activities the person enjoys.
- Establish a nighttime routine to decrease confusion. Behavior tends to worsen at night. Install night lights in the bedroom, halls, and bathroom to reduce disorientation and falls.
- Keep a calendar to check appointments, daily activities, and medication schedules.
- Suggest alternative therapies such as dance, art, massage, the enjoyment of music, and visiting pets.
FAQs about dementia
How common is dementia?
Even though dementia is not an inevitable part of aging, the incidence will tend to grow with an ageing population. Currently, more than 55 million people live with dementia worldwide, with 10 million new cases diagnosed each year.  Between 60 and 70% of these cases are due to Alzheimer’s disease. Dementia is more prevalent in low to middle-income countries and this figure is also expected to rise in the coming years. In the United States, the number of people with dementia is also increasing, but the rate of people with dementia is falling.
What is the outlook for people with dementia?
Dementia is one of the most feared conditions that takes a heavy toll on the patient and their caregivers. While there is no cure for dementia, early diagnosis is crucial as it can help to manage the condition and slow its progression. Depending on the type of dementia, some people may experience symptoms for many years before being diagnosed. This means they may not receive the support they need to manage the condition.
Others may be diagnosed much earlier, often following a health scare or after noticing changes in their own behavior. For these individuals, the outlook is much more positive as they can access treatment and support early on. Support depends on the individual behavioral issues and needs to take into account any co-morbidities (other difficulties or diseases).  Early diagnosis is therefore crucial in determining the outlook for people with dementia.
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