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Sundowning: severe dementia and bringing on the night

James Michael Howard jmhoward at arkansas.net
Thu Mar 27 11:09:34 EST 2003

I have a few ideas to share.  In 1985, I registered my copyright of my
hypothesis that the symptoms of Alzheimer's disease (AD) result from reductions
in availability of the hormone, dehydroepiandrosterone (DHEA).  Subsequently,
DHEA was found to be low in AD.  I think other "dementias" result from the same
thing.  (My principal hypothesis is that DHEA was selected by evolution because
it optimizes transcription and replication of DNA.  Therefore, I decided that
DHEA participates in "growth and development" and "maintenance" of all tissues,
especially in the most advanced tissue, nervous tissues.)  DHEA naturally begins
to decline around age twenty to twenty-five, reaching very low levels in
advanced age.  Now, if one's brain develops under conditions of low, or reduced
availability of, DHEA, then those parts affected by reduced DHEA exhibit
reduced, or less robust, development.  The decline in DHEA in adulthood reduces
maintenance in those parts of the brain so affected.  The result is the symptoms
of AD or dementia.  Not all people develop AD, but "most" do to some extent with
advancing age.  This simply means there are variables in neurodevelopment
intermixed with how fast one loses one's DHEA with age.

Also in 1985, I developed a mechanism of sleep dependent upon high DHEA during
consciousness and high melatonin during sleep.  (You can read this at:
http://www.naples.net/~nfn03605/dheaslee.htm .)  Very basically, for this
answer, DHEA declines at night as melatonin increases.  Therefore, dementia
should increase at night.  A part of my sleep mechanism suggests that too little
DHEA is not good; there must be sufficient amounts of DHEA even at night to
maintain the brainstem so one can shut down higher functions while maintaining
cardiovascular functions.  If this low amount of DHEA gets too low, a trigger
mechanism occurs to raise DHEA sufficiently to maintain the brainstem.  This
will cause severe disturbances of sleep which is characteristic of AD.  Another
part of my hypotheses regarding DHEA suggest that as the frontal lobes of people
with AD decline due to low DHEA, their neurons exhibit the characteristic
malfunctions.  These neurons probably reduce their ability to absorb the already
low DHEA.  This increases destruction of these critical neurons and,
additionally, make DHEA more available for midbrain areas such as the basal
ganglia, etc.  This effect increases the functions of these lower centers.  

So, now to your questions: As DHEA declines at nighttime, disturbed sleep, which
activates the DHEA trigger mechanism, increases DHEA for these midbrain
activities which control aggression, etc.  Another aspect of this explanation is
that as AD continues, the forebrain loss actually increases the availability for
the midbrain functions which control our bodies.  Hence, as AD continues, the
individual actually increases the lifespan.  So, a person with AD lives rather
long after developing the disease; like a poor, former president, Mr. Reagan.  

(Bright light reduces melatonin, so it may help some people by reducing DHEA and
allowing sleep.  That is, the bright light may break the recruitment mechanism
which triggers DHEA release when DHEA is too low.  This could reduce the DHEA
which the mid brain could then use to become activated.)

James Michael Howard
1037 North Woolsey Avenue
Fayetteville, Arkansas 72701-2046

On Fri, 28 Mar 2003 00:39:09 +1000, "John H." <johnh at faraway.xxx> wrote:

>Recently a friend of mine starting working in a dementia ward for severely
>demented individuals. She was advised by other staff that to be careful
>after sundown because many of the patients become violent and extremely
>difficult to control. I'm mystified by this, just wondering if anyone else
>has noticed this in severe dementia and\or if they have any ideas re the
>same. I did note a few months ago a report stating that bright light therapy
>proved beneficial for some dementia patients but this doesn't account for
>the above observations.
>John H.

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