There is a saying that what's good for the heart is good for the brain. This is especially true when considering that individuals who eat high-fat diets, smoke and don't exercise are at higher risk for developing Alzheimer's disease, multi-infarct (vascular) dementia or possibly both. Other risk factors for dementia include old age, alcoholism, brain injury, genetic predisposition and certain diseases.
Age is a Major Factor
The vast majority of individuals with Alzheimer's disease (AD) are elderly. According to the Alzheimer's Association, most individuals with the disease are over 65 years of age and the likelihood of developing AD doubles about every five years after that. Age is also a major risk factor in developing multi-infarct, the vascular form of dementia. It is caused by either complete blockage (causing a stroke) or partial blockage of the blood vessels going to the brain. As the brain is repeatedly starved of oxygen, the risk of dementia increases. Parkinson's dementia is much less common. However, according to Dr. Daniel G Amen, if a person with Parkinson's lives to the age of 85 years, he has a two in three chance of developing dementia.
Family History of Dementia is a Risk Factor
Alzheimer's disease runs in families. According to Dr. Amen, the apoliproprotein E (APOE) gene is the major genetic risk factor for inheriting the late onset form of the disease. On the other hand, the early-onset form of AD is linked to three genes that are different from the APOE gene. It would be unusual for individuals with this gene to NOT develop the early onset form of AD. The APOE gene also increases the risk of developing heart disease and strokes. Interestingly, Africans with this gene, living in sub-Saharan Africa, have lowered risk of developing dementia perhaps because of their lifestyles (low fat/high exercise); whereas African Americans living in the United States have increased risk. Other risk factors for dementia include having a family history of Huntington's disease, Creutzfeldt-Jakob disease and Pick's disease (a form of fronto-temporal lobe dementia).
Alcoholism Increases Risk for Dementia
Although high alcohol consumption increases risk for dementia, a glass of wine once a week appears to lower the risk. Excessive alcohol reduces the amount of oxygen reaching the brain and interferes with the effectiveness of neurotransmitters. Alcohol abuse also worsens the cognitive abilities of individuals who already have dementia.
Brain Injuries and Dementia
Brain injury can cause dementia or make it worse especially if the person has the APOLE gene. The term "dementia" means a decline in previously possessed cognitive abilities and head trauma can cause memory impairment and impact abilities to reason. This type of dementia is not progressive and stabilizes. However, individuals who have experienced brain injury are at greater risk for developing late-onset Alzheimer's disease.
References
- "The Forgetting"; David Shenk, 2001
- "Alzheimer's Disease: Unraveling the Mystery"; National Institute on Aging/National Institute of Health; 2002
- "Preventing Alzheimer's"; William Rodman Shankle, M.S., M.D.and Daniel G. Amen, M.D.; 2004
- The Alzheimer's Association
- "What If It's Not Alzheimer's?"; Lisa Radin and Gary Radin; 2003
