Alzheimer's disease: history, current treatments, and theoretical perspectives

History
The disease first described and defined in 1906 by Alois Alzheimer and named after him in 1910 has led to tremendous breakthroughs in brain and neurological research, according to the Alzheimer’s Association (2018). Alzheimer, a German physician, analyzed the brains of patients with the characteristic symptoms of the disease including profound and debilitating memory loss, noticing “shrinkage,” as well as “abnormal deposits in and around nerve cells,” (Alzheimer’s Association, 2018, p. 1). Alzheimer also described the amyloid plaques now known to be linked to the symptoms of the disease, as well as neurofibrillary tangles (National Institute on Aging, 2018). Since Alzheimer’s early discoveries, subsequent researchers in psychiatry and neurobiology relied on increasingly sophisticated methods of studying the structure of the human brain.
Therefore, technology as well as human input has been instrumental in evolving research into the causes and treatments for Alzheimer’s disease. In addition to the development of specialized microscopes and other brain imaging technologies, researchers have also offered more reliable and valid means of assessing patient symptoms through different approaches like neurochemistry and behavioral science (McGraw-Hill, 2013). For example, during the 1980s, scientific research offered a greater understanding of the role of proteins in cellular degeneration, leading to the development of the first drug ever marketed to treat the symptoms of the disease (Alzheimer’s Association, 2018). Also during the 1980s, a genetic component to Alzheimer’s was first discovered (Alzheimer’s Association, 2018). Brain imaging technologies have also revealed that the region of the brain most significantly impacted by the disease is the Hippocampus, but the disease then spreads from there (National Institute on Aging, 2018). While there is still no known cure for Alzheimer’s disease, research continues to evolve, permitting improved methods of treating early signs of Alzheimer’s disease like cognitive impairment and dementia.
Increased awareness of Alzheimer’s disease has also fostered greater funding into research and development of potential treatments. During the 1990s, President Reagan’s diagnosis with Alzheimer’s disease helped to further increase awareness of the signs and symptoms (Alzheimer’s Association, 2018). In 1999, a vaccine for Alzheimer’s was tested on mice with successful results (Alzheimer’s Association, 2018). Although the vaccine did not yield promising results in human populations, research like this offers hope that one day soon there will be a cure.
Positron emission tomography (PET) scan technologies are helpful in early detection of Alzheimer’s. In 2004, scientists revealed that Pittsburgh Compound B (PIB) attaches itself to the beta-amyloid deposits implicated in the tangled fibers in the brain. Therefore, physicians can use PIB and PET scans for early detection of the disease. In 2009, several other biomarkers were discovered in the cerebrospinal fluid (Alzheimer’s Association, 2018). Genetic research, research into the immune system response, research into the systems involved in brain inflammation, and also research into the various interactions between different neurotransmitters have contributed to improved understanding of the cause and progress of the disease.
Current Theory and Treatment
Recent research has shed light on the precursors of the disease, which tremendously help with the identification of early warning signs and the potential to slow the progress of dementia. For example, the changes in the brain characteristic of Alzheimer’s disease begin at least a decade before the manifestation of memory and cognitive impairment (National Institute on Aging, 2018). These early stages of the disease are characterized by structural changes in the brain but an almost total lack of symptoms (National Institute on Aging, 2018). One of the most promising new areas of research is the link between Alzheimer’s disease and the immune system. Ironically, recent research shows that the very same beta-amyloid protein implicated in the tangled neurons that cause Alzheimer’s might also serve as a prophylactic component of the immune system response (Weintraub, 2016). The new theory of immune response involving beta amyloid contradicts years of research into pharmaceutical interventions designed to rid the body of the protein. Instead, researchers working with the theory that Alzheimer’s is a reflection of a weakened immune system suggest an approach that involves anti-inflammatory medications, diet, and lifestyle changes (Weintraub, 2016). Other research has demonstrated a link between the presence of specific herpes viruses and Alzheimer’s disease (Pomeroy, 2018), and inadequate glucose levels in the brain (Barone, 2018). Yet no theory has been tested empirically to yield conclusive causal evidence.
Because of the lack of one single causal factor and the overall complexity of the disease, Alzheimer’s is notoriously difficult to prevent, treat, and mitigate. Some medications are designed to regulate different neurotransmitters but these only reduce some of the cognitive or behavioral symptoms of the disease and not its biological root causes (National Institute on Aging, 2018). Several drugs can target either the tau protein or the beta amyloid to help reduce the structural degeneration that occurs in the brain, yet none of these drugs have been proven effective (Alzheimer’s Association, 2018). Emerging pharmaceutical interventions also include drugs that help reduce inflammation in the brain, or drugs that help regulate the immune system response to prevent or slow the progress of the disease. For example, a drug called Sargramostin is currently being tested for its ability to stimulate the immune response specifically involved in neuron protection (Alzheimer’s Association, 2018). Genetic research underway may reveal methods of preventing the disease in those who may be at risk. Finally, behavioral and lifestyle interventions can also help with symptom management.
References
Alzheimer’s Association (2018). Milestones. https://www.alz.org/alzheimers-dementia/research_progress/milestones
Barone, J. (2018). What really causes Alzheimer’s? Berkeley Wellness. http://www.berkeleywellness.com/healthy-mind/memory/article/what-causes-alzheimers-disease-new-explanation
McGraw-Hill (2013). PsychSmart. 2nd edition. Kindle Edition.
National Institute on Aging (2018). Alzheimer’s disease fact sheet. https://www.nia.nih.gov/health/alzheimers-disease-fact-sheet
Pomeroy, R. (2018). New evidence for a controversial Alzheimer’s theory. Real Clear Science, 21 June, 2018. https://www.realclearscience.com/quick_and_clear_science/2018/06/21/new_evidence_for_a_controversial_alzheimers_theory.html
Weintraub, K. (2016). Harvard researchers unveil new Alzheimer’s theory. USA Today, 26 May, 2016. https://www.usatoday.com/story/news/2016/05/26/harvard-researchers-unveil-new-alzheimers-theory/85004894/