Dementia Causes

Whether lifestyle can cause or prevent dementia is still largely unknown. Increasing age is the greatest known risk factor for Alzheimer’s and other dementias. According to the Alzheimer’s Association, the risk of Alzheimer’s doubles every five years after age 65.

Genetics may also play a role. National Institutes of Health research shows that those who have a parent or sibling with Alzheimer’s are more likely to develop the disease than those who do not have a first-degree relative with dementia. However, the majority of Alzheimer’s disease is not hereditary. chronic head injuries, as well as education, race, or gender may also increase a person’s risk for developing the disease.  

Although there is no conclusive evidence that lifestyle choices cause or prevent dementia, medical experts acknowledge both the risks and benefits associated with each. Enough evidence-based studies link poor lifestyle choices with increased risk, while healthier choices may lower your risk for the development of the disease. Healthier habits can also boost overall immunity and reduce inflammation while supporting cognitive health.

According to recent guidelines released by the World Health Organization, people can reduce their risk of Alzheimer’s or dementia by adopting the following healthy lifestyle habits:

• Increasing aerobic exercise 
• Quitting tobacco, or not starting use 
• Limiting use of alcohol
• Reducing excess weight
• Including foods like fish, legumes, nuts, and olive oil in your diet
• Eating fruits and vegetables high in folate, vitamin C, D, E and carotenoids
• Maintaining healthy blood pressure, cholesterol and blood sugar levels
• Management of hearing loss

A physically active lifestyle is linked to good brain health. No matter what your age or dementia risk, physical activity can improve your chances of preventing underlying processes related to cognitive decline in early adulthood.

WHO also provides guidelines for physical activity, dependent upon their level of intensity. A minimum of an hour and a half to three hours of activity per week is recommended. This activity should include periods of aerobic movement (raising heart rate) for at least 10 minutes at a time and muscle strengthening exercises. The less intense the activities, the more they should be completed throughout the week.

Researchers at Harvard University found evidence that eating foods with flavonoids can help to keep the mind sharp. Flavonoids are the chemicals that give plant foods their bright colors. The strongest protective effect came from yellow and orange vegetables and fruits.

High-flavonoid foods include:

• Apples
• Blackberries
• Blueberries
• Celery
• Cherries
• Grapefruit
• Kale
• Onions
• Oranges
• Parsley
• Pears
• Peppers
• Raspberries
• Red cabbage
• Strawberries
• Soybeans
• Tea
• Wine

Based on promising study results, the Alzheimer’s Association also recommends increasing your mental activity as a measure to prevent dementia. 

Mental activities and brain exercises include:

• Board games
• Crossword puzzles
• Crafts and hobbies
• Learning a new skill
• Reading
• Working
• Volunteering
• Socializing
• Gardening
• Dancing 
• Playing an instrument

Sources

“What are the Causes and Risk Factors of Alzheimer’s and Other Dementias?” Alzheimer’s Association. https://www.alz.org/alzheimers-dementia/what-is-alzheimers/causes-and-risk-factors 

“Alzheimer’s in extended family members increased risk of disease, study shows”. National Institute on Aging. https://www.nia.nih.gov/news/alzheimers-extended-family-members-increased-risk-disease-study-shows 

“Disparities Related to Education, Race, and Gender Compound Health Disadvantages at Older Ages”. PRB. https://www.prb.org/resources/disparities-related-to-education-race-and-gender-compound-health-disadvantages-at-older-ages/ 

“Risk reduction of cognitive decline and dementia: WHO guidelines”. World Health Organization. https://www.who.int/publications/i/item/9789241550543 

“Lifestyle changes can help prevent dementia”. Harvard T.H. Chan School of Public Health. https://hsph.harvard.edu/news/lifestyle-changes-can-help-prevent-dementia/ 

“Can I Prevent Dementia?” Alzheimers.gov. https://www.alzheimers.gov/life-with-dementia/can-i-prevent-dementia#what-do-we-know-about-reducing-risk-for-dementia 

Also known as alcohol-related brain injury, alcohol-related brain damage is a form of cognitive impairment that develops as a result of prolonged, heavy alcohol consumption, usually over many years. In some individuals, it manifests as only minor changes in thinking and memory known as mild cognitive impairment. Persons with this level of brain damage may develop symptoms such as:

• Trouble remembering important information, such as appointments
• Trouble with short-term memory
• Forgetting recent conversations
• Poor judgment or decision-making
• Difficulty remembering sequences of complex tasks
• Trouble processing visual information 

However, some individuals will develop more severe symptoms that are consistent with dementia, such as progressive memory loss, visual-spatial difficulties, problems managing simple tasks, and personality changes such as lack of interest, irritability, lack of empathy and aggression.

Unlike Alzheimer’s disease and other forms of dementia, alcohol-related brain damage is amenable to treatment as long as the afflicted person abstains from alcohol. 

Causes of ARBD

Alcohol-related brain damage is the result of alcohol’s toxic effects on the brain. These include the following:

• Damage to nerve cells: The brain is made up of billions of nerve cells, or neurons. Over time, excessive alcohol use can damage these cells, causing them to die and the brain to shrink. 
• Damage to blood vessels: Excessive alcohol consumption affects the ability of the blood vessels to expand and contract normally, causing decreased blood flow to the brain. It can also lead to high blood pressure and increased risk of stroke. 
• Thiamine deficiency: Thiamine (vitamin B1) is essential to the normal functioning of nerve cells in the brain. Chronic alcohol abuse causes decreased absorption of thiamine from foods and also impairs utilization of thiamine by the cells. Combined with poor nutrition, these factors cause thiamine deficiency, which leads to cell damage and cell death. In some people with severe thiamine deficiency, this ultimately causes acute brain inflammation (Wernicke’s encephalopathy) and a form of dementia known as Korsokov’s syndrome, which may be permanent. 

Research suggests that in most cases, these factors work together to cause alcohol-related brain damage.

Sources

“Alcohol-related brain damage (ARBD): what is it and who gets it?”. Alzheimer’s Society. https://www.alzheimers.org.uk/about-dementia/types-dementia/alcohol-related-brain-damage-arbd 

“Mild Cognitive Impairment (MCI)”. Alzheimer’s Association. https://www.alz.org/alzheimers-dementia/what-is-dementia/related_conditions/mild-cognitive-impairment 

“Wernicke–Korsakoff syndrome”. Alzheimer’s Society. https://www.alzheimers.org.uk/about-dementia/types-dementia/wernicke-korsakoff-syndrome 

“Alcohol-related dementia: an update of the evidence”. National Library of Medicine. https://pmc.ncbi.nlm.nih.gov/articles/PMC3580328/

According to the CTE Center at Boston University, chronic traumatic encephalopathy is a neurological condition that stems from repetitive brain trauma, either due to multiple concussions or multiple subconcussive hits to the head. First identified in boxers in the 1920s, the disorder is now known to affect retired football players and other athletes who sustained multiple head traumas during their careers. These repeated traumas trigger progressive degeneration of brain tissue and the buildup of an abnormal protein known as tau in the brain. 

CTE typically progresses in four stages, according to a study published in the journal Brain in 2012. Typical symptoms at each stage include the following:

Stage I 

• Frequent headaches
• Loss of concentration
• Attention deficits

Stage II

• Depression
• Mood swings
• Explosive behavior
• Short-term memory loss
• Impulsivity
• Suicidal ideation
• Disruption in executive functions such as thinking, planning and organizing (less common in Stage II)

Stage III

• Increased difficulty with executive functions
• Increasing short-term memory loss
• Worsening impulsivity
• Worsening depression
• Suicidal ideation
• Visual-spatial deficits
• Explosivity 
• Aggression
• Cognitive decline (at this stage of the illness, about 75% of sufferers are “cognitively impaired”)

Stage IV 

• Severe memory loss and disruption of executive function
• Language difficulties
• Worsening visual-spatial deficits
• Gait disturbances
• Aggression, explosivity
• Paranoia
• Dementia 

A significant number of people with CTE will die from symptoms associated with dementia. Suicide and overdose are also among the common causes of death in those diagnosed with CTE. 

Thankfully, CTE awareness has increased in recent years, in part due to the work of Dr. Bennet Omalu, M.D., a neuropathologist who first discovered the characteristic physical changes in the brain of former Pittsburgh Steelers center Mike Webster, who died at the age of 50 after many years of progressive decline. The National Football League has responded to Omalu’s and others’ research by instituting 47 rule changes and a concussion protocol intended to protect players from the kinds of repeated head trauma that lead to CTE. Omalu’s efforts to bring awareness to the dangers of repeated head trauma in athletes are the basis of the 2015 film “Concussion,” starring Will Smith. 

Sources

“What is CTE?” BU Research. https://www.bu.edu/cte/about/frequently-asked-questions/ 

“The spectrum of disease in chronic traumatic encephalopathy”. Brain – Journal of Neurology. https://sites.bu.edu/mckeelab/files/2014/06/The-spectrum-of-disease-in-chronic-traumatic-encephalopathy.pdf 

“Executive Function Disorder”. WebMD. https://www.webmd.com/add-adhd/executive-function#1 

“Bennet Omalu”. Biography. https://www.biography.com/scientists/bennet-omalu 

“Health and Safety-Related Changes for the 2017 Season”. NFL. https://www.nfl.com/playerhealthandsafety/equipment-and-innovation/rules-changes/health-and-safety-related-changes-for-the-2017-season 

Medical researchers suspect that type 2 diabetes is linked to the progression of dementia, and there is some evidence that Alzheimer’s may be caused by insulin resistance in the brain. This neuroendocrine phenomenon has been clinically described as type 3 diabetes, or T3D. The symptoms of type 3 diabetes mirror the symptoms of dementia, such as those seen in early Alzheimer’s disease.

However, the classification of type 3 diabetes remains controversial. It is not yet widely accepted in the medical field, as there are no clinical tests available to confirm the diagnosis. But the label is gaining traction as research continues to show a strong link between diabetes and dementia.

For example, a current study conducted by the National Institutes in Health confirms the implication that type 2 diabetes contributes to the progression of Alzheimer’s disease. Researchers identified the relationship to impaired insulin signaling in the brain. A recent study conducted by Mayo Clinic shows that a type of gene associated with dementia risk may interfere with the brain’s ability to use insulin. 

What Is Type 2 Diabetes?

Type 2 diabetes is a serious long-term condition in which the body is unable to use sugar or glucose efficiently. There are two mechanisms at work in the disease. First, the pancreas does not produce enough insulin, the hormone that allows sugar ( glucose) to be absorbed by the cells. Second, the cells respond poorly to the amount of insulin available, resulting in too much sugar in the blood. High blood sugar levels associated with diabetes can cause circulatory, nervous, or immune system disorders when left unchecked.

Symptoms of type 2 diabetes may include:

• Blurry vision
• Extreme fatigue
• Increased thirst
• Frequent urination
• Increased hunger
• Sudden weight loss
• Slow wound healing
• Tingling, pain, or numbness in extremities 

The American Diabetes Association states that individuals with type 2 diabetes are at a 60% greater risk for the development of dementia compared with those without diabetes. Women with diabetes are at a higher risk for vascular dementia than men. Researchers believe this is because chronic high blood sugar levels damage blood vessels, reducing blood flow to the brain, which causes injury to brain cells over time. Other scientists reason that insulin resistance causes amyloid plaques and inflammation in the brain, which are associated with a diagnosis of Alzheimer’s disease.

Scientists agree that advancements in identifying and treating type 3 diabetes are warranted.   

For now, there are many ways in which you can reduce your risk of developing type 2 diabetes and possibly dementia by making healthy lifestyle choices, such as

• Lose extra weight
• Quit smoking, or don’t start
• Increase physical activity, including aerobic and strength training
• Maintain a balanced diet of fruits, vegetables, and healthy fats
• Manage blood sugar levels with medication, if needed

Sources

“What is the link between Alzheimer’s and Type 3 diabetes?” Mayo Clinic. https://newsnetwork.mayoclinic.org/discussion/researchers-link-alzheimers-gene-to-type-iii-diabetes/ 

“Type 3 Diabetes and Its Role Implications in Alzheimer’s Disease”. National Library of Medicine. https://pmc.ncbi.nlm.nih.gov/articles/PMC7246646/ 

“Mayo Clinic Minute: Is Alzheimer’s Type 3 diabetes?” Mayo Clinic. https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-minute-is-alzheimers-type-3-diabetes/ 

“Type 2 Diabetes”. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/type-2-diabetes/symptoms-causes/syc-20351193 

“Type 2 Diabetes as a Risk Factor for Dementia in Women Compared With Men: A Pooled Analysis of 2.3 Million People Comprising More Than 100,000 Cases of Dementia”. American Diabetes Association. https://diabetesjournals.org/care/article/39/2/300/37175/Type-2-Diabetes-as-a-Risk-Factor-for-Dementia-in