At the turn of the century, because the life expectancy of humans was about half what it is today, most people did not live long enough to acquire dementia, generally thought of as a disease of old age. Today, many men and women live healthy lives, well beyond age 65; however, by age 85, about one-third will acquire a dementing illness.

As Baby Boomers age, this group is rapidly becoming the fastest growing clinical population of interest to speech-language pathologists. The high personal and social costs of dementing illnesses make it imperative that all clinicians stay abreast of advances in diagnosis and management.

What Is Dementia?

The American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Text Revision (APA, DSM-IV-TR) defines dementia as "multiple cognitive deficits manifested by both (1) memory impairment [and]…(2) one (or more) of the following cognitive disturbances: (a) aphasia…(b) apraxia…(c) agnosia…(d) disturbance in executive functioning (i.e., planning, organizing, sequencing, abstracting)."

Dementia is a multi-faceted cognitive impairment that is usually progressive, and always involves "functional" impairments. This means that persons affected by dementia are unable to engage in everyday activities such as spoken and written communication, grooming, preparing meals, driving, and leisure activities with the same level of independence as they had enjoyed earlier in life.

How Do We Diagnose Dementia?

Due to major scientific advances during the Decade of the Brain (1990-1999), there has been a major shift in how neurologists, cognitive scientists, neuroradiologists, neuropsychologists, SLPs, and other health professionals, think about the dementias. These advances have affected diagnostic terms, pharmacologic options, and behavioral interventions. It is important for the reader to understand that the categories "presenile dementia" (before age 65) and "senile dementia" (after age 65) and the location of the neuropathology (i.e., the cortex, or the subcortex) no longer define the major dementia types. Today, the presumed underlying neurologic disease-correlated with the clinical presentation-is the basis for dementia categorization.

Neurologists are the medical specialists with expertise in performing and interpreting clinical tests that rule in or rule out different possible causes. In recent years, several different working groups comprising panels of international experts have developed consensus statements regarding differential diagnosis. By testing patients at periodic intervals, the diagnosis is determined by clinical examination to be "possible," "probable," or "definite." Unfortunately, the gold standard for making a "definite" diagnosis is autopsy.

What Are the Four Major Types of Neurodegenerative Dementia?

There are many types of dementia; some are reversible, but most are irreversible. The neurodegenerative dementias are progressive and irreversible due to deterioration of brain cells and their interconnections. There are four major types of neurodegenerative dementias-Alzheimer's dementia (AD), vascular dementia (VaD), Lewy body dementia (LBD), and frontotemporal lobar dementia (FTD). (The main features of each dementia type are shown in the sidebar on p. 5; essential references regarding diagnosis, in the sidebar on p. 15.)

AD accounts for approximately 60% of all dementias and is the most well-known type. VaD, LBD, and FTD account for the remaining 40% of cases. Importantly, vascular disease may predispose some individuals to acquire Alzheimer's disease, or may exacerbate the clinical course of the disease.

What Factors Correlate With Dementia Progression?

The type of dementia is the major determinant of dementia progression. AD and FTD typically progress slowly; LBD typically progresses rapidly; and VaD progresses in a stair-step fashion, or not at all (if the underlying vascular disease is controlled). Clinical profiles can vary depending on the subtype of the dementia. For example, patients with AD may have the sporadic type, or the familial type. Or, some patients with AD progress rapidly, rather than slowly. Rapidly progressing AD patients often experience onset at an early age, and present with aphasia as an early sign of the disease. Both AD and FLD account for the important subgroup of progressive illnesses-"primary progressive aphasia"-in which a language disorder is often the initial, and sometimes the only sign of progressive cortical degeneration. Finally, within each type or subtype, the severity of dementia is an important indication of the stage of the disease-early, middle, or late.

Do External Factors Influence Dementia?

The World Health Organization approved the International Classification of Functioning, Disability, and Health (ICF) in 2001. This classification system integrates what we know about body structure and functions, activities/participation, and contextual factors (environment and personal factors). One advantage of the ICF approach is that it looks beyond the disease itself to what the person can actually do in his or her work, home, and community environments. 

Clinicians who work with individuals with dementia appreciate the uniqueness of each person, in light of background health, personality, and intellectual capacity, as well as personal goals and achievements. Clinicians also appreciate the heterogeneity of the dementias, when comparing within and across subtypes, and depending on the stage of the disease. A key to understanding the dementias is to appreciate the way the disability itself is shaped by external influences. In short, the functional status of persons with dementia is heterogeneous not only because of the nature of the brain impairment and the stage of the disease, but also as a reflection of external, environmental factors (see External Influences sidebar.)

What Are Some Intervention Approaches?

Most of the behavioral interventions have addressed the most common dementia, AD. However, some case studies have shown intervention benefits for persons with vascular dementia and primary progressive aphasia. Designing interventions for persons with dementia should take into account the communication environment. Factors in this environment would include opportunities for interaction and typical communication partners. Caregivers maintain that eroding communication is the single most distressing problem they face in managing the disease. Therefore, prolonging communication for as long as possible, and at as high a level as possible, is a critical goal of intervention. This requires educating families, nurses, social workers, and other caregivers about communication, and shifting our thinking about intervention to the broad-based ASHA position (1988) of using our knowledge and skills to improve the quality of life in a holistic way. Recent research demonstrates that pharmacologic interventions may enhance the dementia patient's ability to attend, to interact, and to appreciate communication interactions and other essential functions of daily life (Reichman, 2003). If the goals of behavioral or pharmacologic intervention are "reasonable and necessary," Medicare will not deny a claim for services simply on the basis that a person has a diagnosis of dementia (see Transmittal AB-01-135, Centers for Medicare and Medicaid Services at http://www.cms.hhs.gov/Transmittals/downloads/AB01135.pdf, Sept. 1, 2001). 

Direct intervention may include group work focused on social, sensory, and basic cognitive activities. Goals may include participation, appropriate responses to cues, reliance onexternal aids, and so on. Reality Orientation (RO; Folsom & Folsom, 1974) can be used to help participants attend to current life and should be client-centered in determining topics for interaction. Validation Therapy (Feil, 1992) does not attempt to bring individuals into the current reality but instead validates their reality and allows them to lead in choosing topics. The speech-language pathologist acknowledges their emotional state and supports them without correction or confrontation about errors. Reminiscence Therapy (Harris & Norman, 2002) can be used to trigger remote memory and has been associated with improved self-esteem. This intervention works primarily in the early to middle stages of AD. Individual therapy can be used to train compensatory strategies such as the use of memory wallets for memory loss (Bourgeois, 1992). Spaced Retrieval (Brush & Camp, 1998) and errorless learning (Arkin, 1991) are strategies for training new learning that have shown some merit even into the late stages of AD. Montessori methods of multisensory structured activities can also be used to promote engagement and interaction throughout the course of the disease (Judge, Camp & Orsulic-Jeras, 2000).

Indirect intervention refers to interventions with caregivers designed to train them to communicate more effectively with persons with AD. Family members, nursing staff, and others can draw on communication techniques to provide appropriate interaction opportunities to use communication to reduce frustration for themselves and the persons with AD. The FOCUSED caregiver communication program (Ripich, 1996) is organized around seven strategies designed to improve successful communication: Face-to-face, Orient to topic, Continuity of topic, Unstick blocks, Structured Questions, Exchange of turns, Direct short sentences. The program is divided into modules with guidebooks to use in small group training. A series of videotapes for independent learning by caregivers has recently been developed. Studies of outcomes of this program have shown that African American caregivers show greater positive effects compared to Caucasian caregivers and positive results from training maintain for at least 12 months post training (Ripich, Kercher, et al., 1999). Trained caregivers have significantly more successful question and answer exchanges compared to untrained caregivers as well as fewer communication hassles (Ripich, Ziol, et al., 1999). Overall, these studies show FOCUSED to be a helpful behavioral intervention. Other family education programs can be useful in giving families insight into this disease.

SLPs and the Dementias

We have highlighted important advances in two areas relevant to SLPs: diagnosis and management. By integrating new knowledge into their practice, clinicians can offer increasingly valuable services to persons with dementia, their families, and their caregivers. Through early detection and intervention, and the use of innovative management techniques, we can help them improve and maintain communication across the entire course of this disease complex. Because communication connects us as human beings, our efforts to keep individuals with dementia engaged in communication will help keep them engaged in life.