“Did I tell you this already?”
Almost every day there is a new headline about Alzheimer's disease. It is a worry for a lot of people who have aging parents and who are themselves aging. It is, so far, a disease for which there is no prevention and no cure. The headlines tend to be about new research and stress that this or that discovery is only the beginning of a long road toward prevention or cure. The fact is, if there is mental decline beyond that seen with normal aging, there could be a variety of causes, some of which are reversible. Thus, it is important not to harbor generalized expectations about not only the inevitability of dementia but also the root cause. That kind of thinking could keep us from seeking help for someone in the family who seems to be losing his or her edge because we just assume that it is a lost cause. Furthermore, it may prevent us from engaging older people in the use of technology or from participating in other activities that would help them keep up with cultural changes.
Myth #11 As people grow older, they get forgetful, and this is always a sign of dementia
This belief that older adults inevitably become “senile” is so common that a reader of a New York Times blog does not expect anyone to take offense at the opinion expressed in the comments section: “So yeah, I hate it when people use umbrellas in the snow, except for the elderly. I put up with it from the elderly because they're probably weak and senile, and allowances must be made for them” (Hamid & Victor, 2014, February 13).
In the past, when people grew old and seemed ditsy, they were called senile. Senile seemed to imply a kind of inevitability, and eventually the term went out of favor – a not-nice thing to call someone. The term senile dementia had a more serious ring to it and had a brief run. After that, dementia became the common term for symptoms such as difficulties with memory, language, abstract thinking, reasoning, decision-making, and problem-solving. Now, dementiais increasingly referred to by professionals as neurocognitive disorder (American Psychiatric Association, 2013). Nevertheless, we will use the term dementia here because the majority of research to date has not yet incorporated the term neurocognitive disorder. Dementia, rather than senile dementia, makes it easier to remember that these symptoms are not confined to older adulthood – they can result from a stroke or a brain injury at any age. Similar symptoms can also occur as a result of long-term alcohol abuse, a brain tumor, Parkinson's disease (PD), HIV, or multiple sclerosis (MS). And let's not forget dementia pugilistica – aka boxer's dementia.
Even so, the rate of dementia does increase with age. Estimates are that dementia affects 6%, 8%, or even 10% of adults aged 65 and older, and it may affect 25%, 30%, or more of those over the age of 85 (Gatz, 2007; Karel, Gatz, & Smyer, 2012; Knight, Kaskie, Shurgot, & Dave, 2006). There is a higher incidence of dementia among older adults who live in institutional settings – approximately 58% of institutionalized older adults have some form of dementia. That's to be expected because dementia is a major factor in the decisions of family members and/or health-care workers to place older adults in institutions (Skoog, Blennow, & Marcusson, 1996).
Despite the rise in incidence with increasing age, the majority of community-living older adults do not suffer from dementia. But what about the forgetfulness we see in some of those community-living folks? Is forgetting always a sign of dementia? Not necessarily. Some types of forgetting seem to increase with “normal aging.” For example, older adults with no known diagnosis of dementia complain about forgetting specific facts or forgetting names, the latter being especially bothersome. They complain of increased tip-of-tongue experiences (“I know the name of that actor – it's on the tip of my tongue”). Also, older adults report a higher incidence of absentmindedness (Kausler, Kausler, & Krupshaw, 2007), such as walking into a room for some purpose but once there, forgetting what they wanted to do or what items they had planned to retrieve. (By the way, how many times have we all opened the refrigerator only to forget what we were looking for?) In most cases, forgotten facts, names, or intentions are recalled after some delay. Even though older adults themselves may find such memory failures to be annoying, forgetting specific details about an experience and being absentminded are not necessarily ominous signs.
The website www.alz.org/co/in_my_community_alzheimers_symptoms.asp offers some guidelines to help differentiate between memory loss that may be a warning sign of Alzheimer's disease (the most common type of dementia in older adulthood, as explained in the myth that follows) as opposed to typical memory loss that is not necessarily pathological (see Table 2.1).
Table 2.1 Examples of pathological and non-pathological cognitive problems
Source: Adapted from Alzheimer's Association, 2013.
| Potentially pathological behaviors (warning signs) | Non-pathological slip-ups |
| Getting lost going home from work | Getting lost going to the home of a new friend |
| Forgetting having been to the doctor the previous day | Forgetting the date of one's most recent annual physical exam |
| Forgetting rules of a favorite game | Forgetting how to switch from streaming video to TV on a new remote control |
| Being confused about what the current season is | Momentarily losing track of what day of the week it is |
| Having difficulty understanding what one is reading | Momentarily losing concentration while reading |
| Calling things by the wrong name and not correcting it | Sometimes having trouble finding the right word |
| Repeating the same story over and over again | Sometimes telling the same story to the same person twice |
| Putting things away in unusual places and then not being able to find them | Misplacing things from time to time |
| Giving a significant amount of life savings to a telemarketer | Making an ill-considered purchase within one's budget |
| Neglecting to bathe | Neglecting to floss |
Note that potentially pathological signs include forgetting skills and abilities that, presumably, were carried out with ease at a previous time (e.g., forgetting how to play a familiar game or find one's way around in a familiar neighborhood). The list also includes forgetting, or neglecting to perform, basic activities such as bathing. Most people are capable of performing these activities as part of everyday living. Another behavior considered ominous with regard to impending dementia is repetition of the same question or repeating the same story over and over again within a very short period of time. So when Aunt Sally tells you the same story that she told you last month, it doesn't qualify as “over and over again within a very short period of time.” Just listen politely and don't worry about her, especially if that is the only sign of trouble.
In a recent report on data from 16,964 women (aged 70–81) who participated in the Nurses' Health Study (Amariglio, Townsend, Grodstein, Sperling, & Rentz, 2011), some older adults who had not been diagnosed with dementia expressed an awareness that their memory failures went beyond normal forgetfulness. This subjective cognitive decline suggests that older adults themselves may be able to detect when their forgetting is an ominous sign of a potentially pathological process.
Nevertheless, it is not always a simple matter to differentiate forgetting that occurs with the normal aging process from that which signifies the early stages of dementia. Age-associated memory impairment (AAMI) refers to mild forms of memory loss that occur as people get older (Butler, Lewis, & Sunderland, 1998). AAMI doesn't sound like such a terrible thing, but researchers have been trying to differentiate between AAMI and memory loss that foreshadows Alzheimer's disease (AD) or some other type of dementia. Older individuals with more than the typical level of cognitive problems are usually said to have mild cognitive impairment (MCI). A subcategory of MCI is amnestic MCI. Memory impairment is the most prominent cognitive symptom, and people with this diagnosis earn lower scores on memory tests than their age peers do. However, they do not meet the criteria for AD because they do not experience confusion or difficulty with language, and they are still able to carry on with the normal activities of daily living. As of 2013, MCI is also being referred to by professionals as mild neurocognitive disorder (American Psychiatric Association, 2013).
Brain-imaging studies in which older adults complete certain cognitive tasks have shown that different regions of the brain are activated in those with amnestic MCI as opposed to those without it. Are older adults with amnestic MCI at greater than average risk for eventually developing dementia? Thus far, the answer appears to be yes. Over a 4.5-year period, approximately 55% of those classified earlier as having amnestic MCI progress to a diagnosis of dementia, as opposed to less than 5% of those classified as having normal memory (Salthouse, 2010). For this reason, amnestic MCI is now viewed as a potential precursor to dementia. Even so, it is still not possible to predict with certainty which people targeted as having MCI will eventually be diagnosed with dementia. Nor is it possible to explain why, down the road, a small percentage of individuals without amnestic MCI may end up developing dementia.
Myth #12 Alzheimer's disease, dementia – they're one and the same
Many people equate dementia and Alzheimer's disease, often using the terms interchangeably. Dementia affects neurons (brain cells), their connections in the brain, or both. That organic problem causes all of the symptoms that people associate with Alzheimer's disease. In actuality, AD is just one type of dementia, although based on what we know at the present time, it does seem to be the most common type to affect older adults, accounting for approximately 50% of dementia cases in that age group (Cohen & Eisdorfer, 2011).
AD usually has a gradual onset, so initially it can be difficult to detect. Over time, there is noticeable deterioration in cognitive functioning, and eventually this cognitive impairment affects not only memory, but also language and problem-solving, and indeed the very integrity of the individual's personality. Confusion and disorientation are often seen in the late stages of AD, as is the inability to perform basic tasks of everyday living such as being able to dress, feed, and toilet oneself. These problems have been traced to the death of neurons, the breakdown of connections between them, and the extensive formation of neuritic plaques and tau (the chief component of neurofibrillary tangles), which interfere with neuron functioning and neuron survival (National Institute on Aging, National Institutes of Health, Alzheimer's Disease Education and Referral Center, n.d.). Plaques and tangles are seen in the brains of very old individuals for whom there was no behavioral evidence of dementia prior to death (Snowdon, 1997), but generally these are much less extensive than they are in the brains of AD victims (Skoog et al., 1996).
Vascular dementia (VaD), the second most common form of dementia, accounts for 15% to 20% of dementia cases in older adulthood. Risk factors for VaD are advanced age; being a smoker; having diabetes, heart disease, or a history of stroke or hypertension (Skoog et al., 1996). VaD is associated with blockage of cerebral blood vessels, which usually results in focal destruction of brain tissue (Gatz, Kasl-Godley, & Karel, 1996). Focal destruction means that one specific part of the brain is affected, as opposed to the more generalized breakdown of brain cells that occurs with AD. Multi-infarct dementia (MID) is a type of VaD resulting from strokes (Cohen & Eisdorfer, 2011). In contrast to the gradual and insidious onset of AD, VaD comes on more abruptly. Also, in contrast to AD's slow but steady downhill progression, deterioration can be stepwise and fluctuating (Skoog et al., 1996), possibly due to a series of strokes, each of which may be followed by an incomplete recovery over a period weeks or months (Knight, 2004). As well, the course of VaD is not as lengthy as that of AD – approximately 50% of those diagnosed with VaD survive less than three years (Rockwood, 2006) versus at least 10 years or longer for people diagnosed with AD prior to age 80 (National Institute on Aging, National Institutes of Health, Alzheimer's Disease Education and Referral Center, n.d.). Also, personality is more preserved to the end with VaD than it is with AD. For reasons that are not completely understood, AD affects a larger number of older women than older men, even taking into account the overall greater female longevity, whereas men are more at risk for VaD.
Even so, differential diagnosis (arriving at the correct diagnosis when several conditions with similar symptoms exist) of AD and VaD is not always straightforward because at any given point in time, the symptoms overlap. Computed tomography (CT) and magnetic resonance imaging (MRI) scans are sometimes used to make a determination. CT scans can detect areas of cerebral degeneration (or atrophy) in the structure of the brain, and MRI scans use magnetic fields to detect abnormalities in soft tissue. If scanning techniques detect small focal lesions in the brain, a diagnosis of VaD or MID is suggested. Scans that detect large spaces (vacuoles) in the brain are more indicative of advanced AD. Just to confuse matters further, it is not uncommon for people aged 85 and older to have both AD and VaD (Corey-Bloom, 2000; Rockwood, 2006; Whitehouse, 2007). Furthermore, recent thinking among scientists is that vascular risk might be a common factor for both VaD and AD (Gatz, 2007).
Another form of dementia, dementia with Lewy bodies (DLB), was named after Frederick Lewy, who was the first to identify the abnormal microscopic protein deposits found in neurons, typically only with post-mortem histology. DLB has been gaining greater attention, in part because it is more common than was previously thought. In fact, it may be the second or third most common type of dementia among older adults, accounting for 10% to 15% of autopsied dementia cases (Cohen & Eisdorfer, 2011). Lewy bodies occur both in the brain stem and the cortex, which may explain why individuals with DLB have motor as well as cognitive symptoms. With DLB, movement disorders (e.g., shuffling gait, tremors, and muscle rigidity) are similar to those found with Parkinson's disease, which may explain why DLB is often misdiagnosed as PD. With PD, however, cognitive symptoms usually do not occur for a year or more after motor symptoms appear. In the case of DLB, cognitive symptoms similar to those found with AD usually occur simultaneously with motor symptoms. As with AD, the cognitive symptoms worsen gradually over time, but there is more alternation between confusion and clear thinking with DLB. Individuals with DLB have sleep disturbances and recurrent visual hallucinations, and they are especially at risk of falling. Autonomic symptoms such as difficulty with swallowing and fluctuations in blood pressure are often seen as well. Diagnostic criteria are still being developed for DLB because of its behavioral and symptomatic overlap with both PD and AD (Block, Segal, & Segal, 2013).
Yet another form of dementia is frontotemporal dementia (FTD), which is associated with progressive neuron deterioration in the frontal or temporal lobes of brain (Snowden, Neary, & Mann, 2002). FTD (sometimes called Pick's disease after the physician who first described it in 1892), is characterized by changes in social behavior and/or problems with language. Examples of behavior changes are lack of social tact, changes in food preferences, neglect of personal hygiene, and inability to demonstrate basic emotions. Language problems might include repeated use of a word or phrase or decline of speech output altogether. Memory problems are generally absent in this disorder. Typically, FTD is diagnosed when people are between 45 and 65 years old, whereas AD, VaD, and DLB occur more commonly in the later years. Once diagnosed, FTD progresses steadily and often rapidly.
In sum, not all dementia is Alzheimer's disease, and the recommended treatment is not identical for all types of dementia. Thus, it is important to diagnose a problem as accurately as possible. For AD, prescription medications may lessen the symptoms for some amount of time, although medications have not yet been developed that lead to a cure or a permanent cessation of the downhill course of the disease. For VaD, however, timely intervention and treatment of the underlying cause (e.g., diabetes, high blood pressure, strokes, and so on) could help prevent it from progressing. For DLB, modifying the environment to ensure it is designed to prevent falls and to accommodate other movement difficulties, and carefully monitored medications, can help to control the symptoms (Block et al., 2013). Finally, dementia-like symptoms can be reversible when they are caused by such factors as nutritional deficiencies, reactions to medications, and hypoglycemia.
Myth #13 There's no help for Alzheimer's, so don't waste time or money on diagnosis of memory problems
At present, there does not seem to be a cure for AD, but that does not negate the importance of a differential diagnosis. First, medications may offer temporary relief of symptoms. Second, the environment can play an important role in how well and for how long a person with AD can continue to live with some degree of independence. Third, without early diagnosis, the success of any possible interventions is diminished. Fourth, people who are in the early phases of AD may have a lengthy period of time when they are capable of functioning at a sufficiently high level that will allow them to arrange their affairs and plan for the type of care they wish to have before they are no longer able to do so. Fifth and finally, what initially appears to be AD could in fact be a different problem, one for which there may be more effective treatment.
Research on the cause(s) of AD is still unfolding, and the effectiveness of the available medications is less than we would wish. However, some drug therapies do help many patients to a degree, and additional potentially effective medications are under development. It is certainly worthwhile to obtain a diagnosis in case one of these medications can delay any increase in the symptoms.
How can the environment influence the length of time a person with AD may be able to live independently? Certain environments can provide the support needed to bridge the difficulties that a person with AD may experience. One way to understand environmental issues is to consider the case of President Ronald Reagan. In 1994, Reagan announced to the world that he had AD (Ronald Reagan Presidential Library, 1994, November 5). There is a bit of a controversy about whether he had symptoms while still in office (see e.g., Maer, 2011). If he did, however, it is likely that the presidential environment protected him from the consequences. He didn't have to drive a car; he had a personal assistant to make sure he didn't forget appointments; he had staff to prepare meals and balance his checkbook (do presidents even have checkbooks?); he did not have to risk getting lost – the Secret Service saw to that. But what happens when an older person who lives alone starts having symptoms? At what point does that person (and his or her relatives) need to know what to expect down the line? People with AD need a plan. They cannot live alone as the disease progresses, and those who live with them need to prepare for the caregiving responsibilities.
With an early diagnosis of AD, afflicted individuals have the opportunity to make good use of the time left before the symptoms become too severe. People can make independent decisions while that is still possible. They may need to get current on health-care proxy paperwork, create or update a last will and testament, make their wishes known about who will care for them, or even take that trip to Sicily they have been looking forward to. Financial planning is also important because of the costly care they may need. Finally, people with an early diagnosis may be able to cope better with their symptoms if they understand what is to come.
An excellent reason to seek an accurate diagnosis when there are cognitive symptoms is that the problem may not in fact be AD. An article in Parade Magazine (Chen, 2012, November 11) describes the case of a 59-year-old man who had been a top-notch salesman but suddenly began to have difficulties with speech and walking, and later on with remembering familiar things such as his wife's name. Numerous consultations with doctors over the next seven years resulted in diagnoses ranging from Parkinson's disease to Alzheimer's disease. Finally, nine years after the man's symptoms first appeared, a neurologist ordered an MRI, which showed he had normal pressure hydrocephalus (NPH). With NPH, fluid surrounding the brain is not properly reabsorbed, and this eventually causes problems with walking and memory. To reduce pressure in the brain, a surgeon can treat NPH by drilling a hole in the skull and implanting a shunt that drains excess fluid. This surgery resulted in the man's recovery of the ability to walk and a dramatic improvement in his memory.
Not all cases are as dramatic as that of the 59-year-old salesman. However, if the root cause of a person's cognitive symptoms is poor circulation, high blood pressure, or a stroke or strokes, treatment could prevent these symptoms from progressing and, hopefully, improve a person's functioning. The cause of cognitive symptoms can be determined only with the proper screening procedures for cerebrovascular disease and risk factors such as smoking or hypertension. As mentioned earlier, there is recent speculation about whether vascular risk is a common factor not only for VaD but possibly AD as well (Gatz, 2007). If so, then treatment of circulatory issues could be helpful for VaD and, indirectly, for AD.
Recently, Matthews et al. (2013) reported evidence for a decline in the prevalence of dementia in the U.K. Study participants were 7,635 people aged 65 years and older who were assessed between 1989 and 1994, and 7,796 people aged 65 and older who were assessed between 2008 and 2011. The number of people with dementia in the latter group was 24% lower than would have been predicted just based on population aging alone. Certainly, we must be cautious in generalizing to the U.S., but there is good reason to believe that a similar phenomenon is occurring in developed countries in which there have been improvements in the prevention of vascular disease and education about this and related health issues.
Another potential culprit when people experience cognitive difficulties is medication side effects. Some medications may cause memory problems. For example, statins (e.g., Lipitor®, Zocor®, and Crestor®) are a class of drug used to control cholesterol. In February 2012, the U.S. Food and Drug Administration officially added a safety alert to the prescribing information, citing a risk (though rare) of memory loss. Sleep aids have also been implicated in cognitive impairment. For example, warnings for the popular drug Ambien® now include the fact that for elderly patients, the drug dose should be lower than it would be for younger patients because of the increased risk of impaired cognitive performance (Sanofi-Aventis, 2013).
What about using several drugs at once, or so-called polypharmacy? A study of adults aged 57 to 85 (Qato et al., 2008) found that 29% used at least five prescription medications concurrently – and prescription medication use was highest among those aged 75 to 85. Among those users of five prescription drugs, 46% used over-the-counter meds as well. The number of over-the-counter medications that older adults take is alarming, and when combined with prescription medications, the result could be cognitive impairment. It is worth investigating whether drug side effects, drug interactions, or both could be at the root of memory problems.
In sum, there are many reasons why early diagnosis of a memory problem is not a waste of time or money: (a) medications may be of some benefit; (b) the environment can be manipulated to buy extra time for independent living even with a progressive disease; (c) early diagnosis may reveal a condition that is amenable to intervention; (d) a patient may be able to make good use of limited time for making important decisions and fulfilling lifetime dreams or goals; and (e) the problem may not actually be AD, but could turn out to be a partially or completely reversible condition.
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