Is it Alzheimer’s?

Download PDF

There are few things more frightening to someone who is getting older than the thought of Alzheimer’s disease.   The possibility of losing one’s memories, one’s past, one’s identity, is far scarier for most seniors than the inevitability of their deaths.  After fifty years or so of age, every small memory lapse, every forgotten name, every misplaced set of car keys, comes with the worry that this could be the first sign of Alzheimer’s disease.  Since there is no cure for Alzheimer’s disease, many older people will not see a doctor about memory problems because, if they have Alzheimer’s disease, they just do not want to know.  Some older people even neglect other health issues, believing that it would be better for them to die from a heart attack or cancer then to live long enough for the dreaded Alzheimer’s disease to take their minds.  The problem with this kind of thinking is that many memory problems are not signs of Alzheimer’s disease.  They are instead caused by much more treatable conditions, or are really non-problems, the results of normal ageing processes or altered living conditions that make minor changes in cognitive ability more apparent.

The first question that someone should be asking themselves if they think that they might have a memory problem is whether or not their memory is actually getting worse.  Twenty year olds sometimes forget their computer passwords or put the dish washing liquid in the refrigerator, but they do not give these mental lapses a second though.  We all forget things and make some stupid mistakes.  Older people dwell on these kinds of slips and worry about what they could mean.  The truth is that the human nervous system has a built-in error rate of about 1-2%.  It is part of the way that our brains learn to do things better.  Every once in a while, your brain does something wrong, because sometimes the error turns out to not be error after all but are actually represents an improvement.  Unlike machines, humans just cannot do something the same way every time.  Airline pilots have long known this and rely on physical check lists to avoid making fatal mistakes on take offs and landings.  Doctors similarly have begun to use checklists for routine procedures to reduce medical errors.   So, before worrying too much about a mental slip, you should ask yourself if this kind of thing has been happening all the time or if it is a rare event and you are just giving it more attention than it deserves.

The next question that you should be asking yourself is whether the memory task itself has recently become harder.  Most of what we all do on a day-to-day basis involves routine tasks that are carried out largely by unconscious regions of our brains and are cued by signals around us.  If you drive a car that you have had for years, along a route that you have traveled hundreds of times to a grocery store you have been shopping in for ages, all that your working memory (cerebral cortex) has to concern itself with is the handful of items on your grocery list.  If you move, or get a new car, or start shopping at a new store, then the list of things that you have to consciously remember has gotten longer.   You now have to actively think about how to turn on the rear window defogger, which intersection you need to make a turn at, and where the refrigerated section is located.  The probability of forgetting any one specific item increases when the number of items on the list increases.  If you retire, all your work-related time and space cues will be lost and you will have to make a specific effort to remember to take the trash cans out to the curb on the right day, check your gas gauge, and make a special trip to the drug store or supermarket.  While you have now more free time, you also have fewer cues to remind yourself of the things that you still need to do.  Similarly, if you had a spouse or roommate who tended to notice when you left your car keys, wallet, or glasses in an unusual place and moved them to your nightstand for you, or routinely reminded you about errands or returning phone calls, your brain had been using that person as a sort of offsite data storage and processing unit, allowing your own mind to devote more working memory to other things.  If that person dies or moves out, you will now have to add all of those things to your own list of things to remember.  The point is that changes in your life circumstances can make it appear that you are getting worse at remembering things, when in fact there are just a whole lot more things that you have to remember.

Some reduction in memory and concentration with age is inevitable.  From birth onward you have been losing brain cells faster than you have been making new ones.  Most of the brain cells lost in the earliest years were ones that did not make the proper connections or were not doing anything useful.  They would have allowed you to speak Urdu fluently, but since no one around you was using those speech sounds, they served no purpose.   Brain cells require a lot of energy to maintain and your body is not willing to expend resources forever on cells that do not pulling their weight.  Throughout your life, the number of neurons in your brain is continually decreasing, while the amount of information and life experience is increasing.  By around seventy years or so the situation reaches a crisis point.  Unless you do something about the problem, there will not be enough active working memory available for you to function in your day to day life, let alone learn anything new.  At this point, a healthy brain will start cleaning out the storage space and downsizing its operations in order to maintain critical functions.  Information will be prioritized and your brain will begin strategically discarding items that have not been used for years and are unlikely to be needed in the future.   At the same time, your brain will begin refusing to store new items it deems to be of low importance.  Requests for multitasking will be denied in order to assure that you have enough working memory space to accomplish important tasks.  So, if you find yourself forgetting things, you should be asking yourself whether the missing information actually had any real or lasting importance.   Was the name that you forgot that of a mere former acquaintance?  Were the items you forgot to pick up at the store, things that you could, and probably should, have just written down on a list?  Was the fact you could not recall something which you could easily look up and therefore did not need to commit to memory?  If your answers to these questions tell you that you that you are still able to remember all of the important things, but just not so much of the trivial stuff, then there probably nothing wrong with your mind.  Your brain is simply making smart decisions about how to allocate limited resources.   The plus side of this downsizing is that healthy ageing brains tend to get better at finding and identifying critical pieces of information.  Without all of the extra clutter, older minds often do much better in emergency situations than younger brains.  They immediately dial 911, reach for the fire extinguisher, or perform first aid without having to sort through all possible courses of action.

You should also be aware that a number of health problems can interfere with your brain’s ability to store, retrieve, and analyze information.  Severe physical or emotional pain, elevated levels of stress hormones, lack of sleep, interrupted blood flow to the brain, head trauma, or seizures, as well as some pain medications and anesthetics can all interfere with your brain’s ability to store new information, retrieve old information, or reason effectively about what to do in the present circumstances.  Soldiers talk about the fog of war, when major errors are often made in distinguishing friend from foe and heroic or cowardly acts can be performed with no subsequent memory of them.   ER doctors are not the least surprised when car accident or gunshot victims cannot tell the police what happened to them.   Ambulatory surgical clinics routinely ask patients to have a responsible adult with them to listen to the post op instructions and stay with the patient in their homes until they are clear headed enough to manage on their own because they know that the anesthetic in their patient’s bloodstreams will make it difficult for them to even remember that they have been given instructions or to take sensible precautions to avoid self-injury.   If you have been in a lot of pain lately, the mental fog that you have been laboring under may pass along with your kidney stones, or leave your body with the removal of your gall bladder.   A pace maker may allow you to be both more physically active and mentally alert.  Treating depression with medication and/or grief counseling may not only help you cope better emotionally with your problems, but also improve overall mental functioning.  In general, it is always a good idea to look at treating any underlying health conditions before assuming that one’s mind is failing.   

If there are no obvious new or worsening health problems and you or someone that you love is starting to forget important things or is having trouble concentrating on even a single task, then you should be considering whether this change has come about quickly or slowly.   Episodes of delirium, which is generally a short term and reversible problem, can easily be mistaken for signs of dementia, which tends to indicate a more permanent problem.   Delirium is a state of mental confusion with impaired memory, concentration, and reasoning ability which is sometimes accompanied by delusions or hallucinations, and comes on rather quickly, over a period of hours or days.  Delirium is generally due to the brain attempting to operate under sub optimal conditions.  Doctors and nurses see it all the time in intensive care units.  Your brain requires a very narrow range of conditions in order to operate effectively.   If the temperature is too high or there is too little oxygen, not enough sugar, or an imbalance of sodium potassium and calcium in the blood stream, the neurons cannot function properly.  Since the parts of the brain that control conscious thinking use a lot of the neurotransmitter acetylcholine, drugs which affect the ability to make acetylcholine or keep it around, can interfere with memory, concentration and reasoning ability.   

If mental functioning seems to suddenly get worse or if it fluctuates during the day, you should be thinking about delirium and looking for possible causes.  Any illness or injury can cause a fever high enough to trigger delirium.  Since older people often have lower appetites and thirst and they sometimes chose to eat or drink less in order to avoid the need for frequent bathroom breaks, malnutrition or dehydration could also be the cause.  Since many medications slightly reduce levels of acetylcholine levels, and older people are often taking several medications and break them down at slower rates, medication side effects should also be considered.  Since cholesterol is the starting material for producing some neurotransmitters and is also an important component of neuronal membranes, there is also some concern that over aggressive cholesterol lowering treatment may contribute to mental confusion in some patients.   Some of these possibilities can be evaluated on your own but others require consultation with a medical professional.   The possibility of fever can easily be checked with a thermometer and you can always try drinking a couple of extra glasses of water a day or adding a nutritional supplement, but you would want to talk to a doctor about possible medication side effects.   Changing medications or adjusting dosages may restore mental clarity if the delirium is being caused by a medication side effect.

Dementia differs from delirium primarily in that it develops more slowly.  Dementia is progressive, does not tend to fluctuate during the course of the day, and with few exceptions, is not readily reversible.  Individuals with dementia can have good days and bad days, but their good days are not all that good.  Someone experiencing a medication induced episode of delirium may be totally fine a few days after they stop taking that particular medication but someone with dementia is not likely to show any such dramatic improvements.  Dementia differs from normal age related memory loss in that the pattern of information lost is not related to the importance of the information.  Dementia does not respect the individual’s priorities for which memories to keep or lose.  Similarly, concentration tends to be poor even when the conversation or project is something important to the individual.  Someone with normal age related memory loss may not be able to recall the name of his former co-worker’s wife while someone with dementia does not remember the name of his own wife.  Someone with normal aging changes in concentration may find that he cannot make himself follow a conversation about a sport he does not watch while someone with dementia has to ask his doctor to repeat the questions about chest pains.  Someone experiencing normal age related changes may decide to give up on an adult learning class that wasn’t as interesting as they thought it would be while someone with dementia may be forced to give up a hobby that they love.  Normal aging is just annoying.  Dementia is more of a real problem.   

Even if someone is showing the signs of slow mental decline characteristic of dementia, it may not be Alzheimer’s disease.   Many cases of dementia are caused by other conditions, including a few such as vitamin deficiencies or thyroid dysfunction, which are easily treatable and reversible.  Dementia which is caused by a slight overproduction of the cerebrospinal fluid which bathes the brain called normal pressure hydrocephalus can also be stopped and sometimes reversed if caught early enough by surgically implanting a shunt to drain off the excess fluid.  While most causes of dementia cannot be reversed at present, many can be stopped or slowed if the source of the problem is identified.   Exposure to neurotoxins such as carbon monoxide from poorly function home heating or car exhaust systems or smoking, mercury from coal ash waste, or lead particulates from shooting ranges, can slowly damage the central nervous system.  Stopping further toxin exposure by having your car or heating system repaired, stopping smoking, or wearing a particle mask and washing your clothing after going to the gun range may prevent any further mental decline if such slow neuronal poisoning is the source of the problem.   Breakdown of small blood vessels in the brain (vascular dementia) can also cause memory and concentration problems.  This type of vascular damage in the brain can be caused by cardiovascular disease, or by chemotherapy or radiation treatments for cancer.  Small bleeds in the brain due to elevated levels of anti-clotting medications used to prevent heart attacks or strokes can also produce a similar type of vascular dementia.   Cardiovascular disease may be controllable with diet, exercise, and/or medication to slow any further mental decline.  If blood test determine that clotting rates are too slow, dosages anticlotting medications can be lowered to halt further damage caused by spontaneous bleeding.  The damage caused by cancer treatments may not be avoidable, but it tends to be limited and increasing antioxidants in the diet may further limit the damage.   Furthermore, regular exercise can help protect the brain from neuronal loss from all causes.

Alzheimer’s disease can only be conclusively diagnosed by examining the brain after an autopsy but it does tend to show a slightly different pattern of symptoms than others forms of dementia.   In Alzheimer’s diseases, the time that a memory was formed seems to be one of the main determinants of when the memory is lost.  Newer memories tend to be lost before older memories and individuals with Alzheimer’s disease often think that they are living at an earlier time in their lives.  Emotional connections to loved ones tend to be retained by people with Alzheimer’s disease longer than the memory of who the person is.   If the son of someone with Alzheimer’s disease looks a lot like their father or grandfather did at the same age, the person with Alzheimer’s disease might mistake their own son for their husband or father.  A person with Alzheimer’s disease may still be happy to see a loved one, even though they do not know who the person is and believe themselves to be six or sixteen rather than seventy-six.  Individuals with Alzheimer’s disease are also more likely to have disturbed sleep and wander around at night then individuals with other forms of dementia.   So, over time, doctors can say with a pretty high degree of confidence that an individual is suffering from Alzheimer’s disease, rather than some other form of dementia, but the diagnosis not it is not necessarily a clear cut at early stages of the disease.  Current medications for Alzheimer’s disease only slightly delay disease progression but things like daily exercise, remaining social engaged and mentally active, eating an antioxidant rich diet, and taking low dose aspirin have all been shown to significantly slow mental declines in people with Alzheimer’s disease.  As these behavioral and dietary changes have little or no downside if the dementia is caused by something else they can be tried even if the diagnosis is uncertain.   Regular exercise continues to be the best thing that you can do to protect your brain from damage from all causes and to promote repair. (See: The Four Best Things You Can Do For Your Brain)

Alzheimer’s is a scary disease but allowing the fear of this condition keep you from seeing a doctor to assess your condition can be counter-productive.   Since many of the causes of mental decline can be treated, not checking out these possibilities may mean missing out on an opportunity to reverse, halt, or at least slow down any mental decline.  You should not just assume that there is nothing you can do.