Among the most devastating things to hear is that a loved one has been diagnosed with Alzheimer’s disease. Families can feel helpless as they watch the disease slowly progress and change someone so dear and familiar into someone almost unrecognizable. Primarily impacting seniors, it destroys brain cells and leads to memory loss, decline in brain function, and ultimately death. First described in 1906, to date there is still no cure for Alzheimer’s.
While the number of newly developed cases per 100,000 appears to be declining (attributed to improvements over 20th century risk factors such as controlling hypertension which may be linked), overall numbers of those affected will rise. This is commensurate with a burgeoning aging baby boomer population as the longer we live, the more risk we have of developing Alzheimer’s disease. An estimated 6.5 million Americans currently have Alzheimer’s, a number that could increase to more than 12.7 million by 2050. At this time it is unknown how COVID-19, including infection with SARS-CoV-2 (the virus that causes COVID-19), mortality from COVID-19, and changes in health care access resulting from the pandemic will impact the number of people in the U.S. with Alzheimer’s.
While there are medications that may influence memory loss and reasoning skills by boosting the performance of brain cells, researchers hope they can soon develop treatments that stop the progression of the disease altogether—or even prevent it if a new blood test detects early signs.
Brain Changes and Causes
Alzheimer’s disease is characterized by the following changes in the brain:
- Plaques, the microscopic clumps of a protein fragment called beta-amyloid.
- Tangles, the twisted microscopic strands of the protein tau (rhymes with “wow”).
- Loss of connections among brain cells responsible for memory, learning and communication. These connections, or synapses, transmit information from cell to cell.
- Inflammation triggered by the body’s immune system.
- Eventual death of brain cells and severe tissue shrinkage.
The exact cause of Alzheimer’s disease is undetermined, but scientists attribute its onset to a mix of genetic, environmental, and lifestyle factors. It is generally believed genetic factors may play a more significant role.
In 1993, researchers identified the first gene that raises a person’s risk for developing Alzheimer’s. Over the past few years, scientists have made substantial progress in identification of 20 other genetic variations that can increase the risk of development, some of which are specific to the immune system.
Drugs and Clinical Trials
The U.S. Food and Drug Administration (FDA) has approved medications in two categories: drugs that have the potential to change disease progression in people living with Alzheimer’s and drugs that may temporarily mitigate some symptoms.
The National Institute on Aging (NIA) is currently supporting 365 active clinical trials on Alzheimer’s disease and related forms of dementia. These prevention and intervention trials reflect diverse drug and mechanistic targets, as well as diversity in the stages of dementia they address. Trials include early-stage clinical drug development (61); late-stage clinical drug development (11); non-drug interventions (120); care and caregiver interventions (155); and other types of trials (18).
Though drug failure is prevalent, a controversial anti-amyloid antibody drug called aducanumab, marketed as Aduhelm™, is reportedly the first to show that preventing amyloid beta buildup—the sticky plaques in the brain identified with Alzheimer’s disease—is “reasonably likely” to reduce cognitive and functional decline in those with early-onset Alzheimer’s. Plaques disrupt communication between nerve cells in the brain and may also activate immune system cells that trigger inflammation and destroy disabled nerve cells. Interfering with this process may prove significant in stemming the tide of the disease.
Past efforts have focused on drugs that prevent or eliminate plaques, but some newer trials are instead focused on strengthening cells’ protection against neurological attacks. A team at Stanford University School of Medicine has been studying the treatment LM11A-31, or C31, in combination with anti-amyloid (plaques) and anti-tau (tangles) therapies that could prove to counter several neurological problems.
According to the team, the C31 drug can intervene at any stage of the disease. Stanford’s Dr. Frank Longo found that C31 can disrupt at least 10 of the 14 brain signals that may eventually lead to neuron deterioration.
While research for an Alzheimer’s cure and prevention continues, campaigns for awareness of and support for those with the disease also are increasing. In 2011, the National Alzheimer’s Project Act was signed into law. It is the first national strategy to address the Alzheimer’s crisis and to plan for future research, improved care for those with the disease, and support for those affected.
Among the more comprehensive resources for information related to Alzheimer’s disease and other forms of dementia is the U.S. Department of Health and Human Services website, available here.
Though there is currently no guarantee of prevention, seniors and others may reduce the risk of developing it (and may even slow its progression) by eating a healthy diet, maintaining a healthy weight, exercising, keeping blood pressure and cholesterol levels in check, and avoiding smoking and drinking too much alcohol.
“Are We Close to a Cure for Alzheimer’s?” written by Beth Herman and Taylor French, Amada blog contributors.