Alzheimer's disease: is a cure in sight?
Scientists across the world are working hard to find ways to prevent, treat and cure Alzheimer's disease, which affects almost 36 million people globally. But are they making any progress? Here is an overview of the most recent findings.
First described in 1906 by Dr. Alois Alzheimer, Alzheimer's disease is the most common form of dementia, accounting for around 60-80% of cases. It is characterized by problems affecting memory, thinking and behavior.
Onset is most common in individuals aged 65 and over, although people in their 40s and 50s can develop what is known as early-onset Alzheimer's.
Alzheimer's is a progressive disease, meaning memory loss is mild in the beginning, but it worsens over time to the extent that individuals are unable to have conversations or respond to their surroundings.
There are treatments that have been approved by the US Food and Drug Administration (FDA) for Alzheimer's. For example, cholinesterase inhibitors and memantine can help treat memory and thinking problems. But these drugs just help manage the symptoms; there is currently no cure for the disease.
In the US, around 5 million people aged 65 and over are living with Alzheimer's, the majority of whom are women. This number is expected to almost triple to 16 million by 2050. Figures are similar worldwide; by 2050, more than 115 million people are expected to have the disease.
Current Alzheimer's prevalence in the US makes it the 6th leading cause of death, killing more than half a million seniors every year. To put this in perspective, Alzheimer's disease currently kills more people each year than prostate cancer and breast cancer combined.
According to Heather Snyder, PhD, director of medical and scientific operations at the Alzheimer's Association:
“As the 6th leading cause of death, Alzheimer's disease is the only cause of death in the top 10 that we currently do not have a way to prevent, or to stop or slow its progression.”
What have the numerous studies taught researchers about Alzheimer's so far?
As with all diseases, knowing exactly what causes Alzheimer's is key to identifying ways to prevent and treat the condition.
Past research has indicated that Alzheimer's occurs when two abnormal brain structures - plaques and tangles - damage and kill nerve cells, causing the memory, thinking and behavioral problems associated with the disease.
Plaques are fragments of a protein called beta-amyloid, which build up in areas between nerve cells. Tangles are twisted fibers of a protein called tau, which accumulate inside brain cells.
Although the jury is still out on the exact roles plaques and tangles play in the development of Alzheimer's, studies have suggested that build up of these proteins begins long before symptoms develop.
"Evidence suggests that the process of Alzheimer's disease begins more than a decade before clinical symptoms appear, suggesting we may need to intervene earlier to have a major impact on the course of the disease, particularly when using therapies designed to prevent the development of abnormal protein structures - plaques and tangles - that are abundant in the brains of people with Alzheimer's," says Snyder.
Other research has suggested that targeting these abnormal structures could treat Alzheimer's. An article published earlier this year by Medical News Today reported on a study by researchers from the University of California-Irvine, suggesting that increasing brain cell connections could reduce plaque accumulation.
"If amyloid accumulation is the driving cause of Alzheimer's disease, then therapies that either decrease amyloid-beta production or increase its degradation could be beneficial, especially if they are started early enough," says the first author of this study, Mathew Blurton-Jones.
Some studies claim that lifestyle factors may be a driver of plaques and tangles typical of Alzheimer's. Research from Temple University in Philadelphia, PA, for example, suggests that chronic sleep deprivation may cause these abnormal brain structures. Another study suggests regular caffeine consumption could halt development of tangles, while research from the Icahn School of Medicine at Mount Sinai in New York, NY, claims eating grilled meat can increase the development of plaques.
Alzheimer's and genes
More recently, researchers have found evidence that genes play an important role in the development of Alzheimer's.
Studies have shown that the majority of early onset Alzheimer's cases are inherited - a form of the condition known as familial Alzheimer's disease (FAD).
FAD can be caused by one of an array of gene mutations found on chromosomes 21, 14 and 1. Researchers have found that these gene mutations can lead to the development of abnormal proteins in the brain. For example, mutations on chromosome 21 can cause formation of abnormal amyloid precursor protein (APP).
According to the National Institute on Aging (NIA), such findings so far have helped researchers better understand how brain abnormalities form in early-onset Alzheimer's. They have also led to the development of imaging tests that can show how abnormal proteins build up in the living brain.
Lack of research funding and volunteers as an obstacle
Although there has been good progress in the Alzheimer's research field, organizations believe there is a lot more that needs to be done, particularly when it comes to funding.
James Pickett, head of research at the UK's Alzheimer's Society, says:
"Dementia is the biggest health and social care challenge of our generation, but research into the condition has been hugely underfunded. This lack of funding has hampered progress and also restricted the number of scientists and clinicians working in the dementia field."
He is not wrong. In the US, for example, Alzheimer's research received $504 million in funding from the National Institutes of Health last year, while cancer received more than $5 billion. Breast cancer alone even received more funding than Alzheimer's, at $674 million.
For Snyder, this lack of funding is something that needs to be overcome in order to develop new treatment and prevention strategies for Alzheimer's.
"Other diseases have demonstrated that sustained investment in research can improve lives, reduce death rates and ultimately produce effective treatments and preventions," she said. "We have the tools and the talent to achieve breakthroughs in Alzheimer's disease, but we need the resources to make this a reality."
We can and will solve the Alzheimer's disease epidemic'
Alzheimer's and health care organizations admit that there are a lot of challenges to tackle before a cure for the disease is found.
But there is certainly a great deal of confidence that one day, Alzheimer's will be eliminated from existence.
"It is impossible to predict whether this breakthrough is round the corner, but we are definitely making progress in the right direction," said Pickett. "We now understand much more about the progression of Alzheimer's disease and researchers are finding ways to identify people in the earliest stages where they have the best of developing treatments that work."
Snyder agreed, adding:
"At the Alzheimer's Association, we are optimistic about the future, and our urgency continues to grow. We can and will solve the Alzheimer's disease epidemic."
Author: Honor Whiteman
Text abridged and adapted / Nov.2015
With kind permission to publish from MNT
To read the complete article, please go to: Medical News Today