Understanding Vision Change In Aging HD Patients

As the aging process gradually transforms our bodies, changes in vision are a natural evolution.  Since we enter the era of most dramatic eye degeneration around the same time as HD onset, it is important to understand how vision naturally changes and how that may add to the challenges Huntington’s presents.

In parallel to the average age of HD onset, one of the most common processes affecting vision, called presbyopia, develops around age 40. Presbyopia is the gradual hardening of the eye lens, which causes difficulty in focusing on small objects or close items. Presbyopia is typically treated with reading glasses, bi-focals or transitional lenses. As hardening continues with time, so too prescriptions may need repeated adjustment from year to year.

Other frequently developing conditions include decreased color vision, dry eyes, and tearing (having too many tears). Peripheral vision loss also begins, at a rate of about one to three degrees per decade of life. By 70 to 80 years of age, there can be a decrease of 20 to 30 degrees of peripheral vision. Additionally, the muscles controlling pupil size loses strength, reducing the eyes’ responsiveness to light. Because of this, adults in their 60’s require three times more ambient lighting to read comfortably than those in their 20’s.

After age 50, the risk of eye diseases increase, particularly for glaucoma, macular degeneration, and cataracts.

While technically classified as an age related disease, cataracts are so common some consider them a natural part of aging. Cataracts cause blurred or hazy vision and can exist as small easily ignored areas, or cover the entire eye. Cataracts disrupt contrast sensitivity, which is the ability to discern between bright and dim elements in a static image. Research from Indiana University indicates that symptomatic HD patients also show a decline in this sensitivity. Surgery is the typical treatment for cataracts, and usually restores the vision lost or hampered by the cataracts. However, if the decline in contrast sensitivity is due to HD progression, daily adjustments to create a higher contrast environment can help.

Unlike the hazy look cataracts cause, macular degeneration (AMD) manifests in distorted vision and a dimming or loss of central vision. Macular degeneration is incurable and the leading cause of blindness among American seniors. However, treatments to slow the disease include quitting smoking, eating leafy greens, and taking an AREDs supplement.

Risk for glaucoma increases each decade after age 40, from around 1% up to 12% by age 80. While there is still research ongoing determining the cause, intra-ocular pressure plays an important role. Glaucoma can develop over time, or it can be brought on by eye infections, blocked blood vessels inside the eye, or injury to the eye. In most cases, there are no identifying symptoms until the optic nerve has been damaged. It is for this reason that regular eye exams are crucial for early detection.

HD patients often develop ocular motor apraxia (OMA), a condition where purposeful horizontal and quick eye movement becomes impaired. There are several elements to this apraxia, including delayed initiation of movement, fixation impairment, and inability to follow an object without moving the head. Unlike those that develop OMA due to hemorrage or tumor, OMA in HD patients does not seem to effect the vestibular-ocular reflex. This is the reflex which causes the eye to move in the opposite direction of head movement to maintain image stability.

Like so many elements of Huntington’s, there is no solution to resolve the issue of OMA; however, healthy lifestyle choices such as abstaining from smoking and attention to diet can help reduce the severity of many of these conditions. For some diseases of the eye early detection and condition management is the only path. Understanding how these various impairments present themselves is therefore important not only for ourselves, but for the ones that we look after.

 

References:

http://www.allaboutvision.com/over60/vision-changes.htm

http://www.neurology.org/content/33/10/1268.short

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2643869/

http://en.wikipedia.org/wiki/Fixation_(visual)

http://en.wikipedia.org/wiki/Saccade

http://www.netdoctor.co.uk/diseases/facts/huntingtons.htm

http://en.wikipedia.org/wiki/Oculomotor_apraxia

 

Disclaimer: I am not a doctor. All information in this article is purely for educational and enrichment purposes and is not intended to replace or provide medical advice.

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Understanding Circadian Dysfunction and How We Can (Maybe) Slow Its Progression

Sleep is the interest we have to pay on the capital which is called in at death; and the higher the rate of interest and the more regularly it is paid, the further the date of redemption is post-poned.”–Arthur Schopenhauer

The internet is a veritable buffet of lists: 7 Superfoods to Eat, 10 Relationship Red Flags, 12 80’s Movies You Should Watch Again and, more pertinently to today’s blog, lists upon lists about getting sleep, sleeping better, and the detriments of losing sleep. List fatigue or no, sleep research is still churning out some very interesting data. Specifically, research into the complex process of circadian rhythm and hypothalamus dysfunction, which has specific indications for neurodegenerative disorders.

Sleep disturbance can cause a host of negative influences throughout the body. Sleep deprivation leads to increased irritability, agitation, decline of cognitive function, even disrupting the breakdown of sugar. Since behavior, such as eating, television, and exercise habits, can greatly influence the sleep process, we find that correcting detrimental behaviors can increase the amount and quality of our sleep and return our bodies to a healthy schedule and stasis.

For the HD patient recuperating from a bout of sleep dysfunction may not be as easy as catching a few extra hours of sleep. The major effects of sleep deprivation exacerbate mood disorders and cognitive dysfunction that the HD individual is already experiencing. This can create a spiraling situation for the individual, and further aggravate relationships potentially already under strain. Addressing this issue is of great importance; however, these outward behaviors only scratch the surface of how circadian disruption disturbs the body’s entire system. What we’re examining here is not just sleep and sleep dysfunction. Sleep is a circadian behavior, and research suggests that circadian dysfunction is at play in disease dysfunction for neurodegenerative diseases. For instance, sleep dysfunction can appear in Parkinson’s patients years ahead of visible motor dysfunction.

Understanding the Science

Sleep cycles are controlled by the circadian rhythms in the body, all of which are controlled by the suprachiasmatic nucleus (SCN), a small area located in the hypothalamus. Research has shown hypothalamic function is greatly affected by HD, most easily evidenced through weight loss. It is unclear exactly how this occurs, but research shows possible connections with oxidative stress and mitochondrial dysfunction. The SCN is directly above the optic chiasm and utilizes specialized light receptors to dictate the circadian rhythm timing system. The SCN uses hormones, particularly cortisol and melatonin, to regulate the system. The SCN can be considered the body’s master clock, coordinating the cycles of the body’s various other clocks (which regulate specific organs and systems within the body).

This process effects every aspect of the human body, down to transcription of each cell. These active and passive cycles allow our bodies to “time” its efforts. We can think of the circadian rhythm (and the SCN that regulates them) like the shift in objectives at a 24 hour store. Staff that arrives in the morning ensures displays are ready (the body waking up), handles customers and balances product (sorting out the input as we move through our day), while the night shift cleans up (our body processing our meals, eliminating toxins), fills the shelves (we rejuvenate during sleep), etc.

Circadian Dysfunction

Research by Mortin and colleagues has shown a progressive breakdown of circadian and activity cycles for the HD patient. Preliminary research with mice shows SCN neurons firing more sluggish during the day, and less quietly at night as are found in HD-free specimens. This generates a comparatively balanced activity chart, with activity leveling out between cycles. While we may seek balance in many other areas of the body, this activity level is a dysfunction in the system. The body should be highly active at times and quietly resting at others. This dysfunction leads to the hypothesis that HD patients are further hindered in their ability to process hormones, toxins, and metabolize in the manner it typically would, in addition to becoming less and less able to truly rest the body’s systems.

This dysfunction doesn’t just affect the cognitive and emotional processes. Dr. Chris Colwell of UCLA illustrated that mice experiencing this disruption had elevated blood pressure and pumping dysfunction. Further, Colwell’s research indicated molecular physiology that appeared to be working, but a growing drift in the synchronization of the various systems’ clocks. Colwell’s hypothesis, then, is that circadian dysfunction accelerates disease dysfunction.

Adjusting Behavior in the Face of Disease Acceleration

Following the logic of this hypothesis, what are the steps for retarding the dysfunction? First, we must consider the circadian/sleep dysfunction as an integral part of the disease. Second, we should identify some key elements that present environmental barriers to regulating sleep/circadian cycles.

Our body responds to full spectrum natural light (which is not the same as the “full spectrum” marketing term used for light bulbs) and regulates our cycles accordingly. This means that living under strictly fluorescent lighting, which emits ultraviolet light waves, can confuse the SCN. Hospitals and nursing homes typically have poor lighting in this regard. Many retailers now carry light boxes, which emit up to 10,000 lux. Light boxes are used in what is called phototherapy, and is used for people with circadian disorders as well as sufferers of seasonal affective disorder (SAD). Large units (of the 10,000 lux variety) can run several hundred dollars, with smaller units costing less than $100. Utilizing the light box can delay the onset of sleep and activate the SCN to recognize the active part of its cycle. Blue light glasses can also be obtained, which serve to block the blue light and induce the release of melatonin.

Exercise is a vital element for care, for all individuals, but in particular HD patients. According to a study at the University of Georgia, brief periods of exercise for just 20 minutes facilitates information processing and memory functions. Research out of UCLA illustrates that exercise for merely one week of activity presented increased axonal regeneration. Exercise facilitates brain growth and increases sensory neurons’ ability to create new connections and pathways. This function is vital for those with neurodegenerative disorders.It’s also important to schedule exercise for the morning/afternoon portion of the day. Exercising in the evening or after dinner can delay the release of melatonin and onset of sleep.

The body needs to be conditioned to relax into the sleep cycle. To this end, meals should ideally be scheduled allowing enough time for the body to process it before retiring for bed. Snacking late at night is a common behavior for many adults, but especially HD patients. Curbing late night snacking can help the body shut down properly. As Colwell discussed, refraining from eating late not only aids in bringing on sleep but lead to improved performance on motor tasks.

Prescription medications are another element for consideration. Aside from the possible side effects of a given drug, timing of drug treatment matters. Certain medications, such as betablockers for hypertension, should be taken in the morning, while other medications should be taken in the evening, depending on how the body will metabolize those drugs. Adding a supplement of melatonin can help some whose body isn’t producing enough of the hormone. It’s best to discuss the sleep cycle disturbance or concern with the prescribing physician to ensure that all medication directions optimize the goal of regulating the sleep cycle.

The research into circadian dysfunction in Huntington’s Disease is in preliminary stages, but the combined efforts of many past studies lends the belief that this is a promising area of research. If we can aid in the regulating of the circadian cycle, and if this can help slow the progressive deterioration in the brain, then we’ve got a tangible, actionable course of treatment that can have short term and long term benefits.

References:

http://www.ncbi.nlm.nih.gov/pubmed/12595152

http://www.walgreens.com/store/c/home-health-care-solutions-daily-living-aids-light-therapy/ID=364025-tier3

http://www.webmd.com/sleep-disorders/features/important-sleep-habits

http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2265.1999.00763.x/full

http://www.med.upenn.edu/uep/user_documents/VanDongen_etal_Sleep_26_2_2003.pdf

http://hmg.oxfordjournals.org/content/14/1/39.short

Disclaimer: I am not a doctor. All information in this article is purely for educational and enrichment purposes and is not intended to replace or provide medical advice.

Seth Rogan is stirring up some press today for Alzheimer’s and the seeming lack of congressional interest in the disease. Before we become too personally infuriated with congressional leaders, it’s important to note that most speeches made to congressional hearings are made, not to senators, but to their aides and the staff. However, I whole heartedly agree that a speech about Alzheimer’s should rank higher than a lobbyist’s lunch date. Are we all really comfortable with the knowledge that low attendance is the norm on capitol hill?

On the upside, it’s all generating talk about Alzheimer’s and the plight of “elderly disease” in this country. Here is Rogan’s site, Hilarity for Charity, which seeks to use humor and good times to raise money for a serious cause. All work that is beneficial for not only the Alzheimer’s community but the HD community as well.

http://www.hilarityforcharity.org/

Bob Dylan’s Last Thoughts On Woody Guthrie

After two divorces and numerous misdiagnosis, Woody Guthrie was hospitalized at Greystone Park Psychiatric Hospital in 1956. There he spent five years, until he was moved to Brooklyn State Hospital, where Bob Dylan finally met his idol. Dylan later said of Guthrie, “[He] was the true voice of the American spirit. I said to myself I was going to be Guthrie’s greatest disciple.” (Dylan, pg 244-246) Later this week I’ll be posting an article about shame, but I feel like this relationship of Dylan and Guthrie can help us shed some light on the question of life value. For decades doctors discussed sterilization of HD carriers as if it were the humane treatment option. And often carriers, those who know they are positive for the gene and do not yet experience symptoms, fear that there is no point to their lives because they can see its end.

Sometimes it takes the particularly bright star of a famous individual to shed some light on our own abilities and worth. Could we live without Guthrie’s music? Certainly. Do we benefit as a society, as a culture, as a country, to remember his prophetic words? Certainly. His later years were difficult, there’s no doubt. But without that struggle, his ex-wife would never have founded the Committee to Combat Huntington’s Disease, the organization that today exists as the Huntington’s Disease Society of America. An organization that excels at spreading the every-one-in-it-together mantra that Guthrie wrote so many times into his music.

It’s not likely that I will be written about fifty years from now, as I write about Guthrie. But we need only refer back to the influence Guthrie’s work has had on great artists like Dylan and innumerable others to understand our accomplishments reach beyond our own lives. And to live our life feeling ashamed or useless because we have a glimpse of our end is a disservice to all those we love, those we teach, and those we befriend.

This is Dylan’s Last Thoughts on Woody Guthrie, a song he wrote after seeing Guthrie in the state advanced Huntington’s had left him.

When yer head gets twisted and yer mind grows numb
When you think you’re too old, too young, too smart or too dumb
When yer laggin’ behind an’ losin’ yer pace
In a slow-motion crawl of life’s busy race
No matter what yer doing if you start givin’ up
If the wine don’t come to the top of yer cup
If the wind’s got you sideways with with one hand holdin’ on
And the other starts slipping and the feeling is gone
And yer train engine fire needs a new spark to catch it
And the wood’s easy findin’ but yer lazy to fetch it
And yer sidewalk starts curlin’ and the street gets too long
And you start walkin’ backwards though you know its wrong
And lonesome comes up as down goes the day
And tomorrow’s mornin’ seems so far away
And you feel the reins from yer pony are slippin’
And yer rope is a-slidin’ ’cause yer hands are a-drippin’
And yer sun-decked desert and evergreen valleys
Turn to broken down slums and trash-can alleys
And yer sky cries water and yer drain pipe’s a-pourin’
And the lightnin’s a-flashing and the thunder’s a-crashin’
And the windows are rattlin’ and breakin’ and the roof tops a-shakin’
And yer whole world’s a-slammin’ and bangin’
And yer minutes of sun turn to hours of storm
And to yourself you sometimes say
“I never knew it was gonna be this way
Why didn’t they tell me the day I was born”
And you start gettin’ chills and yer jumping from sweat
And you’re lookin’ for somethin’ you ain’t quite found yet
And yer knee-deep in the dark water with yer hands in the air
And the whole world’s a-watchin’ with a window peek stare
And yer good gal leaves and she’s long gone a-flying
And yer heart feels sick like fish when they’re fryin’
And yer jackhammer falls from yer hand to yer feet
And you need it badly but it lays on the street
And yer bell’s bangin’ loudly but you can’t hear its beat
And you think yer ears might a been hurt
Or yer eyes’ve turned filthy from the sight-blindin’ dirt
And you figured you failed in yesterdays rush
When you were faked out an’ fooled white facing a four flush
And all the time you were holdin’ three queens
And it’s makin you mad, it’s makin’ you mean
Like in the middle of Life magazine
Bouncin’ around a pinball machine
And there’s something on yer mind you wanna be saying
That somebody someplace oughta be hearin’
But it’s trapped on yer tongue and sealed in yer head
And it bothers you badly when your layin’ in bed
And no matter how you try you just can’t say it
And yer scared to yer soul you just might forget it
And yer eyes get swimmy from the tears in yer head
And yer pillows of feathers turn to blankets of lead
And the lion’s mouth opens and yer staring at his teeth
And his jaws start closin with you underneath
And yer flat on your belly with yer hands tied behind
And you wish you’d never taken that last detour sign
And you say to yourself just what am I doin’
On this road I’m walkin’, on this trail I’m turnin’
On this curve I’m hanging
On this pathway I’m strolling, in the space I’m taking
In this air I’m inhaling
Am I mixed up too much, am I mixed up too hard
Why am I walking, where am I running
What am I saying, what am I knowing
On this guitar I’m playing, on this banjo I’m frailin’
On this mandolin I’m strummin’, in the song I’m singin’
In the tune I’m hummin’, in the words I’m writin’
In the words that I’m thinkin’
In this ocean of hours I’m all the time drinkin’
Who am I helping, what am I breaking
What am I giving, what am I taking
But you try with your whole soul best
Never to think these thoughts and never to let
Them kind of thoughts gain ground
Or make yer heart pound
But then again you know why they’re around
Just waiting for a chance to slip and drop down
“Cause sometimes you hear’em when the night times comes creeping
And you fear that they might catch you a-sleeping
And you jump from yer bed, from yer last chapter of dreamin’
And you can’t remember for the best of yer thinking
If that was you in the dream that was screaming
And you know that it’s something special you’re needin’
And you know that there’s no drug that’ll do for the healin’
And no liquor in the land to stop yer brain from bleeding
And you need something special
Yeah, you need something special all right
You need a fast flyin’ train on a tornado track
To shoot you someplace and shoot you back
You need a cyclone wind on a stream engine howler
That’s been banging and booming and blowing forever
That knows yer troubles a hundred times over
You need a Greyhound bus that don’t bar no race
That won’t laugh at yer looks
Your voice or your face
And by any number of bets in the book
Will be rollin’ long after the bubblegum craze
You need something to open up a new door
To show you something you seen before
But overlooked a hundred times or more
You need something to open your eyes
You need something to make it known
That it’s you and no one else that owns
That spot that yer standing, that space that you’re sitting
That the world ain’t got you beat
That it ain’t got you licked
It can’t get you crazy no matter how many
Times you might get kicked
You need something special all right
You need something special to give you hope
But hope’s just a word
That maybe you said or maybe you heard
On some windy corner ’round a wide-angled curve

But that’s what you need man, and you need it bad
And yer trouble is you know it too good
“Cause you look an’ you start getting the chills

“Cause you can’t find it on a dollar bill
And it ain’t on Macy’s window sill
And it ain’t on no rich kid’s road map
And it ain’t in no fat kid’s fraternity house
And it ain’t made in no Hollywood wheat germ
And it ain’t on that dimlit stage
With that half-wit comedian on it
Ranting and raving and taking yer money
And you thinks it’s funny
No you can’t find it in no night club or no yacht club
And it ain’t in the seats of a supper club
And sure as hell you’re bound to tell
That no matter how hard you rub
You just ain’t a-gonna find it on yer ticket stub
No, and it ain’t in the rumors people’re tellin’ you
And it ain’t in the pimple-lotion people are sellin’ you
And it ain’t in no cardboard-box house
Or down any movie star’s blouse
And you can’t find it on the golf course
And Uncle Remus can’t tell you and neither can Santa Claus
And it ain’t in the cream puff hair-do or cotton candy clothes
And it ain’t in the dime store dummies or bubblegum goons
And it ain’t in the marshmallow noises of the chocolate cake voices
That come knockin’ and tappin’ in Christmas wrappin’
Sayin’ ain’t I pretty and ain’t I cute and look at my skin
Look at my skin shine, look at my skin glow
Look at my skin laugh, look at my skin cry
When you can’t even sense if they got any insides
These people so pretty in their ribbons and bows
No you’ll not now or no other day
Find it on the doorsteps made out-a paper mache¥
And inside it the people made of molasses
That every other day buy a new pair of sunglasses
And it ain’t in the fifty-star generals and flipped-out phonies
Who’d turn yuh in for a tenth of a penny
Who breathe and burp and bend and crack
And before you can count from one to ten
Do it all over again but this time behind yer back
My friend
The ones that wheel and deal and whirl and twirl
And play games with each other in their sand-box world
And you can’t find it either in the no-talent fools
That run around gallant
And make all rules for the ones that got talent
And it ain’t in the ones that ain’t got any talent but think they do
And think they’re foolin’ you
The ones who jump on the wagon
Just for a while ’cause they know it’s in style
To get their kicks, get out of it quick
And make all kinds of money and chicks
And you yell to yourself and you throw down yer hat
Sayin’, “Christ do I gotta be like that
Ain’t there no one here that knows where I’m at
Ain’t there no one here that knows how I feel
Good God Almighty
THAT STUFF AIN’T REAL”

No but that ain’t yer game, it ain’t even yer race
You can’t hear yer name, you can’t see yer face
You gotta look some other place
And where do you look for this hope that yer seekin’
Where do you look for this lamp that’s a-burnin’
Where do you look for this oil well gushin’
Where do you look for this candle that’s glowin’
Where do you look for this hope that you know is there
And out there somewhere
And your feet can only walk down two kinds of roads
Your eyes can only look through two kinds of windows
Your nose can only smell two kinds of hallways
You can touch and twist
And turn two kinds of doorknobs
You can either go to the church of your choice
Or you can go to Brooklyn State Hospital
You’ll find God in the church of your choice
You’ll find Woody Guthrie in Brooklyn State Hospital

And though it’s only my opinion
I may be right or wrong
You’ll find them both
In the Grand Canyon
At sundown
Read more: http://www.bobdylan.com/us/songs/last-thoughts-woody-guthrie#ixzz2sDDPXF00

Obsessive Behaviors In HD Individuals

For each of us, HD develops in a unique way. Sometimes our loved ones retain their mental clarity for years. For others, behaviors develop that can seem to imprison them. These behaviors can manifest as rituals or obsessions and are a common product of Huntington’s. The resulting consequences of obsessive compulsive behaviors are familiar to any of us, caregiver, bystander or affected patient. Embarrassment, agitation, desperation, helplessness, all of these are common, frequent, emotions experienced by both caregiver and patient. Understanding how this behavior arises in the HD affected brain can provide some helpful insight for caregivers and relief for patients still cognitively aware of the behavior.

The National Institute of Mental Health (NIMH) characterizes Obsessive Compulsive Disorder as recurring thoughts (obsessions) that compel sufferers to repeatedly perform rituals (compulsions). The most common example that probably comes to mind is the germaphobe, a la Howie Mandel. However, less well known obsessions are still common, such as hoarding, frequent thoughts of violence or persistent thoughts of performing sexual acts (even, perhaps, acts the person dislikes). Research indicates that OCD individuals experience neurotransmitter dysregulation, specifically dopaminergic hyperfunction (over production of dopamine) and serotonergic hypofunction (decreased production of seratonin).

It is no coincidence then, that Huntington’s patients who also have this dopaminergic hyperfunction often exhibit OCD behaviors. Dopamine is a very busy neurotransmitter, sending signals related to reward-motivated behavior, motor function, and the release of several important hormones. In Huntington’s, the mutated Htt protein is particularly toxic to brain cells and its effects begin at the striatum. The striatum, among other responsibilities, balances motivation. Thus allowing one to accurately act on or inhibit a behavior in complex social situations. Further, the striatum is made up of metabotropic dopamine receptors. So understanding this center of the brain, we can see that the HD affected individuals’ striatum is assaulted on two fronts: toxicity and overproduction of dopamine.

This two pronged assault can be seen in both a reduction of inhibitions and an increase in compulsive behavior. Many HD affected individuals are unaware of the severity of their obsessions, particularly in the midst of the compulsive act. If it is a fear driven compulsion, often the patient is unable to determine if the fear is irrational. As cognitive function degenerates, the obsessive behaviors may change or increase in severity. Simple instruction may be ineffective at curbing the undesirable behaviors.

Behavioral therapy and cognitive behavioral therapy are considered the first-line treatments for OCD. A common method is called exposure and ritual prevention. In this approach, the patient is routinely exposed to the trigger and practices refraining from the ritual. For instance, repeated practice of throwing out the garbage may be an exercise for someone hoarding. A similar method called associative splitting can help the brain re-associate the trigger(s). For instance, if spiders trigger a fear driven compulsion, the therapy could involve trying to associate spiders with children’s books, elimination of flies, cartoon images, etc.

Each of these methods can prove more difficult to implement with the HD patient, as the primary dysfunction of the brain system is ongoing and, generally, increasing. Medication is often prescribed to accompany these behavioral treatments, with mixed results on their efficacy versus non medicated patients. Typically these medications include the anti-anxiety, anti-psychotic, and/or anti-depressant medications already commonly prescribed to HD patients. For particularly destructive or socially unacceptable compulsions, i.e. public masturbating, inappropriate sex talk, the best method may be to remove as many triggers as possible until the compulsion can be better prevented. It is important to find a physician who is willing to aggressively treat each element of the HD patient. Because research varies so greatly from one group to another, each patient’s treatment will have to be customized to the individual and have the flexibility to accommodate the patient’s evolving disorder.