Being able to distinguish the differences between
normal aging and very early Alzheimer’s diseases is important in
combating unnecessary fear of Alzheimer’s. Early detection is also
important because, for more people, new Alzheimer’s medicines work
to slow down the symptom progression rather than substantially
improving memory functioning. It is important, therefore, to
intervene before memory loss is profound. Early detection also
allows patients to make key decisions about their medical care and
legal affairs before their thinking becomes confused.
National Institutes of Health statistics indicate that some four
million Americans suffer from Alzheimer’s Disease. Age is
consistently found to be the number one risk factor, with the
percentage of people with the disease doubling every decade after
age 65. By age 85, up to 50% of persons are thought to have
Alzheimer’s. With theses staggering statistics, very few of us so
not have a parent, friend, relative, or neighbor with the disease.
Increasing medical coverage and personal experience have acquainted
us with this devastating illness, and we are frightened that we
might be next.
One of the reasons for concern and fear is
that the first symptoms of Alzheimer’s disease mimic the normal
aging process. Like memory changes associated with normal aging,
Alzheimer’s begins slowly and subtly – a lost telephone number or a
misplaced checkbook. However, unlike normal aging Alzheimer’s
eventually escalates into frank confusion and profound memory loss.
Because of the initial similarities, many people – including
professionals – misinterpret normal, age appropriate forgetfulness
with the first signs of Alzheimer’s disease. In the back of our
minds, when we can’t find the keys a little voice says, ‘What if
it’s Alzheimer’s? ‘
What should we expect with normal
aging? Beginning around age 30, there is a slow and steady decline
in brain weight in normal brains, with age-related atrophy visible
on CT images of the brain by the early 40’s. Brain cell loss is not
uniform, with the greatest loss in the hippocampal and frontal
regions of the brain – those areas responsible for memory. With
normal aging, the ability to create new memories is not usually
impaired. Rather, it is the retrieval of memories that becomes
troublesome. When reminded ("You remember, he was the one with
the…") memories will generally come easily to mind.
Individuals are usually acutely aware of their lapses in memory.
In contrast to normal aging, Alzheimer’s disease impairs
the brain’s ability to create new memories. No amount of reminders
will help to retrieve information, because it was never encoded in
the first place. Another unique signature of Alzheimer’s is the
unawareness of symptoms that patients express. Although clinicians
once assumed this was a psychological denial, it turns out that
unawareness is a neurological phenomenon. The frontal lobe function
of self monitoring, and the ability to remember that one is
forgetting, is compromised by the disease.
there is no blood test or brain imaging device that can distinguish
the earliest signs of Alzheimer’s from the normal aging process.
Detailed neuropsychological evaluation is the clinician’s best tool
for determining the presence of pathological memory changes is in
their earliest stages. Neuropsychological testing works by creating
a model of premorbid (pre-memory problem) brain functioning and
comparing this model to current abilities, with the effects of
normal aging factored out. In this way, subtle changes in reasoning,
language, and memory are exposed. Besides diagnosing early
pathological changes in memory, patterns of strengths and weaknesses
on neuropsychological tests allow clinicians to diagnose specific
dementia syndromes – of which Alzheimer’s is just one – and provide
more complete information to patients and families about what to
expect in the future.
Symptoms which should trigger a
- progressive forgetfulness
- reminders often don’t help with recall
- poor awareness that there is a problem
- decline in reasoning skills, such as
trouble with the checkbook, mistakes in cooking, or in playing
- becoming lost or confused while driving
- excessive worry over memory problems
Karen Spangenberg is a Neuropsychologist at
Northeast Rehabilitation Health Network and has offices in Lowell
and Salem. For more information on Alzheimer’s or other NRH-Network
psychology services, please call 603-893-2900 extension 728.