Overview

Alzheimer's disease is a progressive brain disorder characterized by changes in the brain that lead to the formation of protein deposits. It is the most common cause of dementia, a condition marked by a gradual decline in memory, thinking, behavior, and social skills. As Alzheimer's disease progresses, brain cells shrink and eventually die, leading to severe cognitive and functional impairment.

Approximately 6.5 million people aged 65 and older in the United States have Alzheimer's disease, and worldwide, about 60% to 70% of the estimated 55 million people with dementia have Alzheimer's.

Symptoms

The key symptom of Alzheimer's disease is memory loss, which worsens over time. Early signs include difficulty remembering recent events or conversations. As the disease progresses, other symptoms develop, including:

Repeating statements and questions.
Forgetting conversations, appointments, or events.
Misplacing items in unusual places.
Getting lost in familiar locations.
Forgetting the names of family members and everyday objects.
Difficulty finding the right words or expressing thoughts in conversations.

Other cognitive and behavioral changes include difficulty concentrating and thinking, impaired judgment, trouble planning and performing familiar tasks, changes in personality, mood swings, social withdrawal, and delusions.

Despite the decline in memory and skills, some abilities may be preserved longer, such as reading, listening to music, and engaging in crafts.

Causes

The exact causes of Alzheimer's disease are not fully understood, but it involves the failure of brain proteins, leading to damage and death of brain cells. The disease is likely caused by a combination of genetic, lifestyle, and environmental factors that affect the brain over time. In rare cases, specific genetic changes almost guarantee the development of Alzheimer's.

Researchers are focused on studying the role of two proteins, beta-amyloid (forming amyloid plaques) and tau (forming neurofibrillary tangles), in Alzheimer's disease.

Risk Factors

The primary risk factor for Alzheimer's disease is increasing age, with the chances of developing the disease increasing as people grow older. Family history and genetics also play a role, with certain genes like APOE e4 increasing the risk. Down syndrome, being female, mild cognitive impairment, head trauma, air pollution exposure, excessive alcohol consumption, poor sleep patterns, and heart health-related factors like lack of exercise, obesity, smoking, high blood pressure, high cholesterol, and poorly controlled type 2 diabetes are other risk factors associated with Alzheimer's.

Engaging in lifelong learning, social activities, and maintaining a heart-healthy lifestyle may help reduce the risk of Alzheimer's disease.

Complications

Alzheimer's symptoms can make it challenging to manage other health conditions and may lead to complications such as difficulty communicating pain, explaining symptoms of other illnesses, or following a treatment plan. As the disease progresses, physical functions may be affected, leading to difficulties with swallowing, balance, bowel, and bladder control, which can result in infections, falls, fractures, poor nutrition, and dehydration.

Prevention

Alzheimer's disease is not preventable, but some lifestyle risk factors can be modified. Following a heart-healthy lifestyle, exercising regularly, eating a healthy diet, managing high blood pressure, diabetes, and high cholesterol, and quitting smoking may reduce the risk of dementia. Engaging in mentally and socially stimulating activities is also associated with a lower risk of Alzheimer's disease. While prevention strategies may not completely eliminate the risk, they can contribute to overall brain health.