Narayana Health
Causes and Risk Factors for Alzheimer's Disease
Jul 20, 2023
2 Minutes Read
Neurology Blogs
Overview
Alzheimer's is a progressive and irreversible neurological disorder that primarily affects the brain, leading to decreased memory, thinking skills, and cognitive functions. Alzheimer's disease is characterised by the accumulation of abnormal protein deposits, such as beta-amyloid plaques and tau tangles, in the brain. The causes and risk factors of Alzheimer's include age (especially after 65), genetic mutations (such as APP, PSEN1, and PSEN2), family history, Down syndrome, lifestyle factors (e.g., cardiovascular health, smoking), and head trauma. While these factors increase the risk, they do not guarantee the development of Alzheimer's.
Causes and Risk Factors for Alzheimer's Disease
Alzheimer's disease is a complex condition influenced by genetic, lifestyle, and environmental factors. Here are some most common causes.
Genetic Factors.
- Familial Alzheimer's Disease (FAD). In rare cases, Alzheimer's disease is caused by specific gene mutations inherited from parents. FAD accounts for less than 5% of all Alzheimer's cases, typically manifesting earlier in life (before age 65).
- Apolipoprotein E (APOE) gene. APOE gene variants, specifically the APOE ε4 allele, are associated with an increased risk of developing late-onset Alzheimer's disease (the most common form). However, having the APOE ε4 allele does not guarantee that an individual will develop Alzheimer's, nor does its absence ensure protection from the disease.
- Lifestyle Factors. Conditions that negatively impact heart health, such as hypertension, high cholesterol, obesity, and diabetes, have been linked to an increased risk of Alzheimer's. Maintaining a healthy lifestyle, including regular exercise and a balanced diet, can reduce these risk factors.
- Gene Mutations. APP gene mutations can lead to increased production or accumulation of beta-amyloid protein, which forms plaques in the brain, a hallmark of Alzheimer's. PSEN1 and PSEN2 gene mutations affect the processing of APP, resulting in the overproduction of beta-amyloid.
- Age. As the person grows old, the risk of this disease increases. The risk is greater after age 65, and the prevalence doubles approximately every five years thereafter. This is known as late-onset Alzheimer's disease.
- Smoking. Smoking is associated with an increased risk of developing Alzheimer's disease, and quitting smoking can help reduce the risk.
- Mild Cognitive Impairment (MCI). People with MCI, which involves mild memory and cognitive problems that are not severe enough to be diagnosed as dementia, have an increased risk of progressing to Alzheimer's.
- Medical Conditions. Individuals with Down syndrome have a higher risk of developing Alzheimer's due to genetic factors.
- Environmental Factors. Higher levels of education and engaging in mentally stimulating activities throughout life are associated with a reduced risk of developing Alzheimer's disease.
- Head injuries. Serious head injuries, particularly repeated concussions, have been identified as potential risk factors for developing Alzheimer's disease later in life. Taking precautions to prevent head injuries, such as wearing helmets during sports and using seat belts in vehicles, is crucial.
- Social engagement. Maintaining an active social life and participating in social activities may lower the risk of cognitive decline.
When to Consult a Doctor
Timely medical intervention can help cure many of these ailments or help in managing them. You can also get in touch with the expert Neurology doctors at Narayana Healthcare based in your city to get immediate attention and medical support to treat brain conditions, neurological disorders or any other health concern.
Conclusion
Alzheimer's is a complex neurological disorder characterised by progressive cognitive decline and memory loss. While the exact causes of Alzheimer's disease are not fully understood, research suggests that a combination of genetic, environmental, and lifestyle factors contribute to its development. Genetic factors, such as mutations in certain genes like the APP, PSEN1, and PSEN2 genes, can increase the risk of developing Alzheimer's disease.
FAQs
Q. Does everyone with a family history of Alzheimer's disease develop the condition? A. Having a family history of Alzheimer's does increase the risk, but it does not guarantee that an individual will develop the condition. It is possible to have a family history of the disease and never develop it, just as it is possible to develop Alzheimer's without any known family history.
Q. What are the leading causes of Alzheimer's disease? A. The exact causes of Alzheimer's disease are not fully understood. However, research suggests that a combination of genetic, environmental, and lifestyle factors contribute to its development. Genetic factors, such as specific gene mutations, can increase the risk. Other factors include age, family history, certain medical conditions, and lifestyle choices.
Q. Is Alzheimer's disease hereditary? A. While there is a genetic component to Alzheimer's disease, it is not typically inherited in a straightforward manner. Specific gene mutations, such as those in the APP, PSEN1, and PSEN2 genes, can increase the risk of developing the disease.
Q. Can lifestyle choices affect the risk of developing Alzheimer's disease? A. Yes, lifestyle choices can influence the risk of developing Alzheimer's disease. Chronic stress, smoking, excessive alcohol consumption, a sedentary lifestyle, obesity, and a poor diet may increase the risk.
Q. Can Alzheimer's disease be prevented? A. While there is currently no known cure for Alzheimer's, confident lifestyle choices may help reduce the risk or delay the onset of symptoms. Engaging in regular physical exercise, adopting a healthy diet, staying mentally and socially active, managing chronic conditions, and getting regular medical check-ups are all critical for overall brain health.
