See the Assessment section of the Dementia Evidence Map for pertinent scientific evidence, expert opinion, and client/caregiver perspective.
The diagnosis of dementia is made by a medical team. The role of the speech-language pathologist (SLP) is to assess cognitive-communication deficits related to dementia (e.g., memory problems; disorientation to time, place, and person; difficulty with language comprehension and expression) and to identify cultural, environmental, and linguistic factors that impede functioning.
The SLP determines the most appropriate assessment protocol based on the stage of dementia and the individual's communication needs. In addition, when selecting cognitive-communication screening instruments and subsequent tests for comprehensive evaluation, the clinician considers the cultural and linguistic background of the client, using tests that have normative samples of culturally and ethnically diverse groups when available. Standard scores should not be reported, if the normative sample is not representative of the individual being assessed.
Screening for cognitive impairment is conducted by an SLP or other member of the interdisciplinary care team for individuals with any condition that increases their risk for cognitive-communicative problems, including hearing loss. Many standardized instruments with demonstrated reliability for screening of dementia are available. These instruments typically assess orientation to time, place, and person. Other tests (e.g., story recall/story retelling) assess episodic memory and can be useful for screening for early dementia (Bayles & Tomoeda, 1993; Rabin et al., 2009; Takayama, 2010; Wechsler, 1999).
Prior to screening for cognitive-communication disorders associated with dementia, it is important to consider the impact of sensory impairment, depression, and current medications on cognitive functioning. If screening reveals cognitive impairment, individuals are referred to an SLP for a comprehensive evaluation of communicative function. Referral for other examinations or services are made as needed.
Hearing loss is common among older adults, and many individuals have untreated hearing loss and do not wear hearing aids or make use of other hearing technologies. Audiometric hearing screening and otoscopic inspection for impacted cerumen are to be conducted prior to cognitive-communication screening.
Traditional behavioral tests of hearing (e.g., pure tone and speech audiometry) are generally successful in the early stages of dementia, although modifications such as simplifying directions, using pulse tones, slowing presentation of speech stimuli, providing reminders to respond, and responding with "yes" instead of raising a finger or pressing a button may be needed. During the later stages of dementia, more objective tests (e.g., otoacoustic emissions or auditory steady state response) may be necessary to obtain estimated thresholds (Burkhalter, Allen, Skaar, Crittenden, & Burgio, 2009), as may be modifications of assessment procedures for those patients who do not condition to standard tasks.
If the individual fails the hearing screening, a referral is made to an audiologist for a comprehensive assessment. If an individual has a diagnosed hearing loss and wears hearing aids, hearing aids are inspected to ensure that they are in working order and worn by the individual during cognitive-communication screening. The use of assistive listening technology should be employed when hearing aids are not being used.
If visual deficits are suspected, the individual is referred for vision testing prior to completing cognitive-communication screening. Prescription eye glasses, as needed, are to be worn during screening, and adequate lighting used in the test (and treatment) environment.
Depression is common in individuals with dementia and can adversely affect test performance. Cognitive changes associated with depression so resemble the cognitive changes associated with dementia that depressive symptoms are often referred to as "pseudodementia." If signs and symptoms of depression are present, the individual is referred to a neuropsychologist or clinical psychologist experienced with geriatric depression.
Prior to screening, the SLP considers the effects of prescription drugs on cognitive-communicative function. Polypharmacy, or the concurrent use of several medications, is common among older adults who have multiple medical conditions, and some medications may exacerbate cognitive problems. Questions about the effects of medication use on cognitive-communication functioning can be answered by a pharmacist knowledgeable in geriatric pharmacy.
Individuals suspected of having cognitive-communication problems are referred for a comprehensive assessment of language and communication. SLPs often conduct these assessments in collaboration with neuropsychologists. Assessment may include clinical observations in the home or long-term care setting.
Assessment is conducted to identify and describe
- underlying strengths and weaknesses related to cognition, language, and social/behavioral factors (see Signs and Symptoms) that affect communication performance;
- effects of cognitive-communication impairments on the individual's activities and participation in ideal settings, everyday contexts, and employment settings;
- contextual factors that serve as barriers to or facilitators of successful communication and participation for individuals with cognitive-communication impairment;
- the impact on quality of life for the individual and the impact on his or her family/caregivers.
Assessment may result in
- diagnosis of a cognitive-communication disorder;
- clinical description of the characteristics of a cognitive-communication disorder;
- statement of prognosis for improved outcomes;
- recommendations for intervention and support;
- identification of the effectiveness of intervention and supports;
- referral for other assessments or services.
A comprehensive assessment is sensitive to cultural and linguistic diversity and addresses the components within the World Health Organization (WHO) International Classification of Functioning, Disability and Health (ICF) framework (see ASHA's Scope of Practice in Speech-Language Pathology, ASHA, 2007; WHO, 2001), including body structures/functions, activities/participation, and contextual factors. Assessment should occur in the language(s) used by the person with dementia.
Assessment can be static (i.e., using procedures designed to describe current levels of functioning within relevant domains) and/or dynamic (i.e., an ongoing process using hypothesis-testing procedures to identify potentially successful intervention and support procedures). When dementia is caused by a progressive disease, periodic reevaluation (e.g., yearly) and adjustment of care plans become essential to meet changing needs.
Assessment typically includes
- relevant case history, including medical status, education, occupation, and socioeconomic, cultural, and linguistic background;
- review of auditory, visual, motor, cognitive, and emotional status;
- patient/client and family reports of goals and preferences, as well as domains and contexts of concern;
- standardized and nonstandardized methods selected with consideration for ecological validity:
- observation and description of the individual's processing of various types of information under ideal conditions and in the context of various activities and settings (e.g., ability to attend to, perceive, organize, and remember verbal and nonverbal information to reason and to solve problems);
- observation and description of the individual's executive or self-regulatory control over cognitive, language, and social skills functioning (e.g., ability to set goals, plan, initiate and inhibit, self-monitor and self-evaluate, solve problems, and think and act strategically);
- analysis of the cognitive and communication demands of relevant social, academic, and/or vocational tasks and identification of possible facilitative effects in modification of those tasks;
- identification of the communication and support competencies of relevant people in the environment and possible facilitative effects of modification of their support behaviors;
- identification of the individual's potential for effective compensatory behaviors and associated motivational barriers and facilitators;
- follow-up services to monitor cognitive-communication status and ensure appropriate intervention and support for individuals with identified cognitive-communication disorders.
Assessment of Swallowing
A comprehensive assessment includes a swallowing screening or, if indicated, a swallowing assessment. An estimated 45% of individuals with dementia residing in an institution have dysphagia (Easterling & Robbins, 2008), and dysphagia is more prevalent in patients with Alzheimer's disease than in normal elderly individuals (Horner, Alberts, Dawson, & Cook, 1994). This increased prevalence may be associated with a diminished sense of smell and cognitive changes associated with the progression of dementia (Easterling & Robbins, 2008).
Swallowing assessment with individuals with dementia involves evaluation of
- the oral mechanism;
- the patient's ability to comprehend and use compensatory strategies;
- the individual's oral preparatory, oral, pharyngeal, and esophageal phases;
- the individual's recognition of food and utensils;
- environmental impacts, including the appearance of the food, lighting, and distractions;
- food and liquid trials with a variety of temperatures, textures, tastes, postures, and strategies and consideration for the individual's food preferences;
- the potential impact of the individual's prescribed medications on swallowing function;
- the influence of cognitive factors on feeding and swallowing.
An instrumental evaluation may be performed to determine safety and identify effective treatment techniques or strategies, if the patient is able to respond appropriately and tolerate the procedure. The instrumental evaluation may provide additional information about the oral and pharyngeal bolus transit, airway protection, the impact of bolus texture and size, and appropriate pacing (Easterling & Robbins, 2008).
There are a number of assessment tools that produce a valid characterization of cognitive-communication strengths and weaknesses—including language comprehension and expression and integrity of working, declarative, and procedural memory systems—and that have been standardized on individuals with dementia. The severity level of dementia in the individual being tested is factored into test selection. Some tests are too difficult for the individual with severe dementia and do not yield useful information, because the individual fails most or all of the items.
Assessment in Long-Term Care Facilities
Passage of the Omnibus Budget Reconciliation Act in 1987 mandated evaluation of the physical and psychological status of residents in long-term care facilities at the time of admission and periodically thereafter. The required evaluation, known as the Minimum Data Set (MDS), includes questions about the ability of residents to hear, comprehend, and produce language. Although the law does not require that judgments about hearing and communicative function be made by SLPs, the inclusion of these questions on the MDS helped establish a role for SLPs with long-term care residents.