Dementia is a term used to describe a group of persistent or chronic mental disorders caused by brain injury or disease. It’s recognized by impaired reasoning, personality changes, and memory disorders.

Dementia is not a specific disease; it covers many medical conditions, like Alzheimer’s. Alzheimer’s is the common cause of dementia in older adults, but there are other causes.

Abnormal brain changes cause medical conditions grouped under dementia. The changes trigger a decrease in cognitive abilities or thinking skills, severe enough to impair your independent function and daily life. They also affect feelings, behavior, and relationships.

Though dementia usually involves memory loss, memory loss has different risk factors. Memory loss alone doesn’t signify you have dementia, but it’s one of the early symptoms. 

Types Of Dementia

Types of dementia are grouped into two categories, including progressive (dementias that progress and are irreversible) and reversible (dementia reversed by treatment)

Progressive Dementias

Types of dementias that can’t be reversed include:

• Alzheimer’s disease– is the most common type of dementia. Alzheimer’s disease is related to the mutation of several genes; these genes are passed down from parents to children. Apolipoprotein E4 (APOE) is the most involved gene, which increases the risk of Alzheimer’s disease.

Patients with Alzheimer’s disease have tangles and plaques in the brain. Tangles are fibrous tangles made of tau protein; plaques are protein clumps called beta-amyloid. Clumps are believed to damage healthy neurons and the fibers connecting them.

• Lewy body dementia- Lewy bodies are abnormal balloon-like protein clumps found in the brains of individuals with Lewy body dementia and Alzheimer’s disease. This is among the most prevalent types of progressive dementia.

Lew body dementia signs and symptoms include visual hallucinations, slow movement, acting out your dreams while asleep, losing focus and attention, tremors, and rigidity.

• Vascular dementia – this type of dementia occurs when the blood vessels that supply blood to the brain are damaged. Blood vessel problems can damage the fibers in the brain’s white matter or cause other conditions like stroke.

The primary signs and symptoms include slowed thinking, problem-solving difficulty, losing focus, and organization.

• Frontotemporal dementia – includes disease groups recognized by damaged nerve cells and their union in the temporal lobes and brain’s frontal areas associated with behavior, personality, and language. 

Common signs and symptoms include behavior change, thinking problems, negative personality, and judgemental issues.

• Mixed dementia – autopsy study done on people aged 80 and above indicated that those with dementia stated a combination of several causes, like vascular dementia, Alzheimer’s disease, and Lewy body dementia.

Reversible Dementia-like Conditions

Some conditions of dementia are reversible with treatment. They include:

• Immune and infections disorders –  dementia conditions can result from fever or side effects of body fighting infections. Dementia can also be caused when the body’s immune system attacks nerve cells.
• Metabolic problems and endocrine abnormalities – people with conditions like low blood sugar, thyroid problems, too much or little calcium or sodium, or problems absorbing vitamin B-12 can develop personality changes or dementia-like symptoms
• Nutritional deficiencies –  dehydration, lack of vitamin B-1, and lack of enough vitamins B-6 and B-12 in your diet can lead to dementia symptoms. Deficiency in copper and vitamin E can also be dementia symptoms.
• Subdural hematomas – brain bleeding on the surface covering the brain, especially in the elderly after a fall, causes symptoms similar to dementia.
• Medication side effects – reactions of medications or interactions of some medications can cause dementia-like symptoms.
• Brain tumors – in some cases, damage from brain tumors causes dementia 

Risk Factors

Many factors contribute to dementia. These factors are classified into those that can’t be changed and those you can change.

Risk factors that can’t be changed include

• Family history – dementia can be passed on through genes, from parent to child. A family history puts you at high risk of getting the condition. The risk rises if more than one family member has the condition.
• Age -the risk of Alzheimer’s disease and vascular dementia increases as you age. Though dementia can occur in young people, it mainly affects older adults above 65 years. Research shows that after age 65, the risk of Alzheimer’s disease and vascular dementia doubles every five years. After 85, the risk rises to nearly one-third.
• Down syndrome – is a genetic disorder caused when a person has extra chromosomes. Down syndrome culprits develop dementia-like symptoms by middle age.

Dementia Risk factors that can be changed 

• Smoking and alcohol use – smoking and drinking alcohol increase your blood vessel disease and dementia risk. Smoking often leads to atherosclerosis and vascular diseases, underlying causes of increased dementia. Studies show that heavy drinkers are at higher risk of dementia than moderate drinkers and those who abstain entirely.

• Diet and exercise –  studies show that lack of exercise and an unhealthy diet elevates the risks of dementia. Also, certain conditions like high blood pressure, diabetes, and obesity can increase the risk of dementia. Regular exercise and healthy diets help fight these conditions, which in turn bring a positive effect on dementia risk.

• Depression – older people with depression, are at a higher risk of developing dementia. But research is not detailed on the direction of the relationship. Whether depression causes dementia or dementia causes depression. People with depression symptoms tend to suffer memory loss and thinking problems. These conditions tend to increase the risk of dementia.

• Cardiovascular problems – people who have experienced heart attacks are at risk of developing blood vessel problems in the brain. Brain damage from a stroke increases your risk of dementia. Also, high blood pressure puts excess stress on your blood vessels throughout your body, including the brain. This brings vascular problems to the brain.

• Sleep disturbances – during the day, our brain makes beta-amyloid protein, which is a protein that accumulates to form Alzheimer’s plaques. But, when we sleep, it is at rest and can flush away these substances. Lack of sleep hinders your brain from draining away beta-amyloid and other substances. These substances accumulate and, in the end, cause dementia.