Understanding Diabetes and Alzheimer’s

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Diabetes and Alzheimer's disease are two of the most common diseases that affect older adults worldwide. Diabetes is a chronic health condition that affects the body's ability to process glucose. Alzheimer's is a progressive brain disease that damages brain cells and cell connections, resulting in memory loss and other essential mental functions.

Research suggests that diabetes may increase a person's risk of Alzheimer's disease. Among people without diabetes, almost 2 in 1,000 will develop Alzheimer's. For people who do have diabetes, this rate increases to 6.25 per 1,000 people.

In this article, we discuss the connection between diabetes and Alzheimer's, including how one condition may affect the diagnosis and treatment of the other.

The Connection Between Diabetes and Alzheimer's

Researchers do not yet completely understand how diabetes and Alzheimer's are connected, but they know that diabetes increases inflammation and damages the body's blood vessels.

This can damage many organs in the body, including the brain. According to the Alzheimer's Association, the high blood sugar levels that are often a hallmark of type 2 diabetes are also linked to increased beta-amyloid protein, a key characteristic of Alzheimer's disease.

Researchers believe that the insulin resistance characteristic of type 2 diabetes exacerbates the brain plaques that occur in Alzheimer's disease. Alzheimer's disease is sometimes called "type 3 diabetes" because of its connection to insulin resistance in the brain.

Evidence also suggests that chronic hypoglycemia, or low blood glucose, accelerates cognitive problems in people with Alzheimer's. Glucose is a primary energy source, so the brain is deprived of fuel when blood sugar levels drop. This can result in cognitive damage. One meta-analysis found that diabetic people who experienced hypoglycemic events had a 44% higher risk of developing dementia.

Shared risk factors that increase a person’s chances of developing both conditions include:

  • The ApoE4 gene: There is no specific gene that directly causes Alzheimer's or diabetes. However, people with a variation of apolipoprotein E on chromosome 19 (APOE4) have an increased risk of developing Alzheimer's disease. The gene is also a risk factor for developing diabetes.
  • Elevated blood sugar levels: Chronic high blood sugar levels are associated with developing both conditions. Research has found that people with high blood sugar, even if they don't have diabetes, are more likely to have Alzheimer's disease.
  • Family history: A family history of diabetes or Alzheimer’s can mean that a person might be more likely to develop one or both conditions.
  • Lifestyle factors: Lack of physical activity, poor dietary habits, and other lifestyle factors can also elevate a person's risk of having both conditions.

Complications of Diabetes and Alzheimer's

Having diabetes and Alzheimer's disease can have severe implications for health and functioning. Alzheimer's leads to progressive memory loss and declining function. Over time, people lose the ability to manage tasks required for daily living, including the ability to monitor and manage their blood sugar levels.

Alzheimer’s may increase the risk of poorly managed diabetes, contributing to many other health problems. Diabetes can have a range of complications. Uncontrolled diabetes can lead to heart disease, kidney failure, blindness, nerve damage, and stroke.

When to See a Doctor

If you are experiencing symptoms of memory loss, you should talk to a doctor for further evaluation and testing. While there is no cure for Alzheimer’s disease, there are treatments that can help slow its progression and improve your ability to function.

Diagnosis of Diabetes and Alzheimer’s

Diabetes is diagnosed using blood tests that check for unusually elevated glucose serum levels. Several blood tests may be used to assess diabetes, including A1C tests that measure your average blood glucose levels over the past two to three months. An A1C level of 6.5% or higher indicates diabetes.

Doctors utilize a range of tests and tools to diagnose Alzheimer's disease. they may administer mental status tests, evaluate medical history, conduct a neurological exam, and perform brain imaging tests to look at physical changes in the brain.

If you are experiencing cognitive symptoms, your doctor may diagnose you with major or mild neurocognitive disorder due to Alzheimer's disease. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR) is the tool that professionals use to diagnose mental health conditions.

Self-Test for Alzheimer’s Disease

If you are concerned about early symptoms of memory problems, evaluating your memory may help you better determine if you should talk to your doctor about your concerns. The Self-Administered Gerocognitive Exam (SAGE) is a pen-and-paper self-test designed by researchers from Ohio State University.

The SAGE assessment is not a diagnostic tool, but it can be a helpful screening tool for mild cognitive impairment (MCI), a condition that can increase a person's risk of developing Alzheimer's.

Treatment of Diabetes and Alzheimer’s

Diabetes treatments are focused on managing the chronic condition. This means taking steps such as monitoring blood sugar levels, making lifestyle modifications, and using medications to control glucose levels. Treatments for Alzheimer's disease, on the other hand, primarily aim to slow the progression of cognitive decline.

Medications

Medications that are often prescribed to treat diabetes include Metformin and insulin. Insulin is a hormone that plays a role in the uptake of glucose. Metformin lowers blood sugar absorption, increases insulin sensitivity, and decreases glucose production.

Aduhelm (aducanumab) may be prescribed to help remove amyloid plaques in the brain to improve cognitive functions and slow disease progression. Cholinesterase inhibitors may also be prescribed to help improve memory.

Some evidence suggests that certain diabetes drugs, including Metformin and sulfonylureas, can also help reduce the risk of developing Alzheimer's.

Psychotherapy

Psychotherapy can be helpful for coping with the stress and emotional effects of a diabetes or Alzheimer’s diagnosis. Psychoeducation and diabetes management education can help people better understand their conditions and learn how to manage it effectively.

Coping With Diabetes and Alzheimer’s

After a diabetes or Alzheimer's diagnosis, the individual and their family members need to explore ways to cope. Some strategies that can help improve coping include:

Lifestyle Changes

Learning more about diabetes and Alzheimer's is a great place to start. The early stages after getting a diagnosis are a time of adjustment and learning. Knowing more about the condition and what you can expect can help you better plan for the future.

Making lifestyle adjustments can help you manage your symptoms. Increasing physical activity, following dietary recommendations, losing weight, and quitting smoking are steps you can take that will help.

While it can be difficult, it is also essential to start making plans for the future. If you have Alzheimer's, it is essential to plan how to manage your diabetes once you can no longer do so on your own. Talk to your loved ones and doctor to determine what will work in your situation.

Support Groups

There are also several support groups available for people with diabetes. For family members of people who have Alzheimer's, support groups can be a valuable source of practical advice, encouragement, and understanding.

A few places to look for a support group include the Alzheimer's Association and the VA Caregiver Support Line. You might also consider asking your doctor for information about support groups in your area.

Summary

Diabetes and Alzheimer's are connected in several ways. Evidence suggests that in addition to shared risk factors, having diabetes puts a person at a greater risk for developing Alzheimer's. 

The memory loss and cognitive declines associated with Alzheimer's complicate the management and treatment of diabetes. Getting the right treatment can help control symptoms of diabetes and slow the progress of Alzheimer's disease.

A Word From Verywell

Coping with diabetes and Alzheimer's can be challenging, particularly as symptoms of mental decline progress. With appropriate support and treatment, you can better manage your symptoms. Talk to your doctor about your options and how to plan for the future management of both of your conditions.

10 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Kendra Cherry
Kendra Cherry, MS, is an author and educational consultant focused on helping students learn about psychology.