Alzheimer’s disease is a family legacy of abuse which claims the lives of an estimated 5.4 million people in the United States. For most of the 20th century, there was a widespread lack of research into the disease, largely because of the apathy the field had experienced since it was described in 1952.
However, in recent years there has been a growing belief in the medical community that more needs to be done to both improve the care for those affected and in researching the cause and disease of the disease.
The past 20 years has seen an increased recognition of the genetic causes of dementia and the spread of research into new treatments. In some cases, these discoveries lead to useable drugs – such as Aricept, the drug which is used to treat Alzheimer’s – while in others, some treatments lead to false hope, leading some patients to stop testing as there is no confirmed cure for the disease.
With more than 5 million Americans affected by Alzheimer’s, science and healthcare professionals have a combined goal of understanding the disease and being able to prevent it. Every year, scientists discover new genetic factors that may be involved with the development of Alzheimer’s, and many see the potential for new gene-based treatments, taking a multidisciplinary approach to medical research – something which is encouraged by the National Institute on Aging (NIA).
New data published this week in The Lancet backs up this continued optimism, revealing how the disease is progressing in the brain.
The data, published by researchers at the NIA, NIA Alzheimer’s Disease Cooperative Study, suggests the disease can develop in just 12 years after a person’s first symptom, suggesting more should be done to understand the causes of the disease.
The researchers, whose findings are published in the journal The Lancet Neurology, used a large cohort of participants, 5,000 of whom were enrolled in the NIA’s Florida Memory Study in 2009-2012 and followed for three years. They revealed that cognitive decline associated with the disease was recorded in no later than the second year of follow-up and that these effects correlated with cognitive decline throughout a person’s lifetime.
During follow-up, 1,455 participants developed Alzheimer’s disease while 2,555 did not. The dementia rate was 30.9 per cent during the first year and then fell during the study.
Dr. David Williams, director of the NIA’s Division of Alzheimer’s Disease and Memory Disorders, said: “This study gives a tremendous amount of information to suggest a very early onset of Alzheimer’s in participants who lacked sufficient protective mutations in their APOE genes for this disease to develop by themselves.”
Taken together, the findings of the study provide a “window into the history of Alzheimer’s disease,” he added. This provides “reliable assessment of a new and emerging subtype of Alzheimer’s known as ‘transitional Alzheimer’s’, as well as information about the progression of Alzheimer’s disease over time, its relationship to aging, and factors affecting symptom onset.”
Focused on the region of the brain responsible for memory and learning, the disease affects the different parts of the brain. Although the disease is often confused with the more common amyloid-beta (Aβ) plaque disease, as Aβ deposits are easily seen, the form of the disease is less common.
Instead, most cases develop first in the posterior cingulate cortex, a region of the brain involved in cognitive processes including memory.
Alzheimer’s disease is now linked to abnormalities in the brain stem, known as an “umbilical cord” region, which is involved in transferring information back and forth from the brain stem, which influences memory. The results of the study indicate the disease can be slow to develop.
It is unlikely to be otherwise known until the age of 65 and, by the age of 85, studies have shown that 80 percent of cases are Alzheimer’s, with the remaining 20 percent caused by other dementias such as Parkinson’s and Down syndrome. These findings prove that the disease is present and can develop so early in life.
John Kennedy is a patient research specialist at the NIA in partnership with Alzheimer’s Disease International (ADI). Follow him on Twitter @JohnKennedy40.