There are a number of risk factors that lead to cognitive decline. The main factors are:
The good news is that many risk factors can be controlled effectively by adopting correct lifestyle choices to prevent Alzheimer’s. The three most important ways in which lifestyle modifications can impact our brain health are:
Perhaps the most investigated field of the new millennium is genetics. Diseases such as cystic fibrosis, muscular dystrophy, and Huntington’s disease are single-gene disorders. If a person inherits the gene that causes one of these disorders, he or she will usually develop the disease. Alzheimer’s disease, on the other hand, is not caused by a single gene.
The two basic types of Alzheimer’s are Familial and Sporadic:
Sporadic, late-onset Alzheimer’s disease has no known cause and shows no obvious inheritance pattern. However, in some families, clusters of cases are seen. Although a specific gene has not been identified as the cause of late-onset Alzheimer’s, genetic factors do appear to play a role in the development of this form.
Two risk factor genes have been linked to Alzheimer’s diseases so far. Researchers have identified an increased risk of developing late-onset Alzheimer’s related to the apolipoprotein E (APOE) gene found on chromosome 19. The APOE gene comes in several different forms, but three occur most frequently: APOE e2, APOE e3, and APOE e4. People inherit one APOE from each parent. Having the e4 form is a risk factor for Alzheimer’s disease, but it does not mean that Alzheimer’s disease will necessarily develop. The e3 form is the most common form found in the general population and may play a neutral role in AD. The rarer e2 form appears to be associated with a lower risk of AD.
The second gene that has just been discovered and appears to be associated with a higher risk for Alzheimer’s is the mutated TREM2 gene. Research is underway to establish how this gene plays a role in the development of the disease.
The exact degree of risk of Alzheimer’s for any given person cannot necessarily be determined based on APOE status.
It is possible to evaluate your predisposition to develop Alzheimer’s disease and make lifestyle choices that reduce your risk factors. More and more evidence is emerging that proves environmental factors play a significant role in determining if the disease will develop and progress.