While Alzheimer’s disease (AD) accounts for 60 – 80% of all dementias, this means that 20-40% of those with cognitive, mood or behavioral symptoms will have another form of dementia. There are dozens of conditions that cause dementia. The differences in symptoms are caused by several things:
So why bother with a rigorous diagnostic evaluation when we can’t treat most of these diseases? First, recognize that non-AD dementias often require different medical and care management strategies. Second, the person may have an unfavorable response to medications commonly used in AD. And finally, issues affecting the family differ from AD. For this article we will look at three relatively common non-AD dementias: Vascular dementia (VaD, formerly called multi-infarct dementia); Lewy body dementia (LBD); and Frontotemporal dementia (FTD).
It used to be thought that all dementia was caused by “hardening of the arteries” resulting from decreased blood flow to the brain. This has been disproved, however dementia can occur when there are recurring large and/or small strokes. People with strokes can exhibit slowed cognitive decline usually with preserved awareness. Motor (movement) problems include one-sided weakness, often with spasticity; changes in gait (the ability to walk); or small areas of weakness such as one-sided facial droop or weakness in a hand. Language problems, and even Parkinson-like movement disorders can occur depending on the locations of the strokes. Often the strokes are so small they go undetected until motor changes appear.
People with vascular dementia often have a history of hypertension (high blood pressure), diabetes, and smoking which cause thickening and damage to the very small arteries. This can result mini strokes that leads to slowing and impaired recall of recent information. But, the ability to recognize things and people may stay intact (1). For people with vascular dementia, careful control of medical conditions, especially blood sugar, cholesterol, and blood pressure, is essential to stabilize the condition. Depression is common in vascular dementia and should be treated in order to maximize quality of life. In addition, physical and occupational therapy may produce modest gains in day to day function.
Lewy body disease
LBD, also known as dementia with Lewy bodies (DLB), is an important cause of dementia affecting about 1.4 million people in the US over age 65 (Lewy Body Dementia Association 2015). Lewy bodies are cells that usually occur in Parkinson’s disease (PD). In LBD, the Lewy bodies form in the areas of the brain usually affected by AD, producing a unique set of symptoms (2).
LBD is a complex multi-system disorder requiring careful knowledgeable medical management from a primary care provider and, at minimum, a behavioral neurologist or movement disorder specialist. Physical, occupational, and speech therapies can be helpful from time to time; especially with programs designed for use in PD such as “Big and Loud” programs.
Frontotemporal dementia (FTD) is by far one of the more challenging dementias. It is also commonly referred to as fronto-temporal lobar degeneration (FTLD), or Picks disease. FTD is caused by conditions that cause degeneration/progressive damage to the frontal and temporal lobes. It causes a group of brain disorders that share many clinical features including marked personality change, language disorders, and motor symptoms which may include ALS. In early disease, FTD tends to present on one area of the brain initially producing either personality symptoms or changes in language function. As the disease progresses to the moderate stage it spreads to both areas of the brain leaving the people with both language and personality losses (3). There are several distinct forms of FTD as described below.
Behavioral variant FTD (bvFTD) was formerly known as “Pick’s disease, and is characterized by a loss of the ability to interact socially in a meaningful manner. The person loses empathy towards others, becomes socially inappropriate and self-centered. The ability to reason and plan an activity to reach a goal is impaired and, coupled with the loss of insight (Anosognosia). The inability to inhibit actions may produce behaviors such as hypersexuality, excessive spending, or compulsive eating. Since memory is largely intact, the family cannot rely on the person forgetting to eat or spend money as a strategy to manage the behavior. Instead, the family tries to gain the person’s cooperation and provide structure. However efforts to gain some control and reason often result in paranoid ideas and acting out. This can place care partners and others at extreme risk of personal injury.
Language variants occur in several forms and affect both expression and understanding of written and spoken language. Early in the disease people with primary progressive non-fluent aphasia lose the ability to coordinate the tongue, teeth, palate and muscles to produce speech; yet many have good insight and can continue to live alone. In moderate disease these people become mute, and develop behavioral issues. Many people with FTD develop obsessive behaviors to relieve their stress. Stopping the obsessive behaviors can result in spontaneous vocalizations or aggression.
There are several motor disorders that can develop as part of FTD, the most common being motor neuron disease (FTD-MND or ALS). Others include corticobasal degeneration (CBD), progressive supranuclear palsy (PSP), or a Parkinsonism. After several years of either language or behavioral variant FTD the person begins to develop fasciculation’s or fibrillations (twitching). The person will then lose strength and have a relatively brief survival time.
A major hurdle in care of people with FTD is age. Onset of FTD often occurs in a person’s 50s and 60s, but has been seen as early as 21 and as late as 85 years. Roughly 60% of cases occur in people 45-64 years old, thus FTD can affect work and family in a way dementia in older people does not. People with bvFTD are often working and may have school-aged children. Because of the person’s young age and behavioral disorders they are often misdiagnosed with psychiatric conditions such as bipolar disorder with mania. Treatment rarely succeeds and, because of the diagnostic error the person does not qualify for Social Security and disability benefits.
Referring the family of a person with FTD to an attorney specializing in elder law is a critical first step in providing care. The attorney can help with obtaining benefits (such as Social Security Disablity) and obtaining decision-making authority. Because of the person’s lack of insight they often refuse to sign durable powers of attorney. Moreover, the person with FTD scores well on tests of memory normally used in determining capacity. The attorney can also be helpful with driving cessation and protecting family assets from reckless spending.
In summary, non-Alzheimer’s dementias are relatively common. Because they involve different parts of the brain than AD, they have different symptoms and disease progression. Care of people with non-AD dementias differs from care of AD in several ways:
In summary, it is imperative for families to keep seeking diagnoses and answers to the question “Why doesn’t my person act like others who have AD?” Seeking education and support to manage many of the differences outlined will be essential for good care. For more on this topic, we invite you to join in the March 16, 2016 Dementia Dialogue from 12N – 1pm (AZ time) as Dr. Geri Hall discusses “Non-Alzheimer’s Dementias.” Registration is required and must be done online at www.bannershri.org under events and education and online education OR you can call 623-832-3248.
1. Rosser, M. (2013) The ABCs of neurodegenerative dementias. In Gary Radib and Lisa Radin (eds) What if it’s not Alzheimer’s?, third edition. Amhurt New York: Promethius Books, pp. 35-6.
2. Lewy Body Dementia Association (2015). http://www.lbda.org/category/3437/what-is-lbd.htm retrieved January 3, 2016.
3. Association for Frontotemporal Degeneration (2015). FTD Overview. http://www.theaftd.org/understandingftd/ftd-overview, retrieved January 5, 2016.
4. Liljegren, M., Naasan, G., Temlett, J., Perry, D.C., Rankin, K.P., Merrilees, J., Grinberg, L.T., Seeley, W.W., Englund, E., & Miller, B.L. (2015). Criminal behavior in frontotemporal dementia and Alzheimer’s disease. JAMA Neurol. 72(3), 295-300.