20Q: Mild Cognitive Impairment - The SLP’s Role in Service Delivery

From the Desk of Ann Kummer

Mild Cognitive Impairment (MCI), also called Mild Neurocognitive Disorder (mildNCD), is a condition where the individual has some impairment in one or more cognitive areas, but not to the extent that it could be considered full-on dementia. Most people, regardless of age, have periodic episodes of “forgetfulness.” For example, they may lose their keys, forget to lock their doors at night, or forget an acquaintance’s name. Forgetfulness tends to increase with age and is often considered a normal part of the aging process. However, it could signal the beginning of a more serious cognitive decline that ultimately leads to a form of dementia.

As the baby boomers in the United States are 60 and above, there is an increased prevalence of cognitive impairment. Therefore, it’s important the speech-language pathologists are knowledgeable about MCI and dementia and learn how to develop interventions to support affected individuals.

To help us in our understanding of MCI, Dr. Kim McCullough and Anne Hunter Cox will answer some key questions regarding this topic. Here is a little information about these authors:

Kim McCullough, PhD, CCC-SLP, is a Professor and Graduate Program Director at Appalachian State University. She is a certified speech-language pathologist with clinical expertise in providing services to individuals with neurogenic communication disorders. Her teaching, clinical activities, and research focus on interprofessional practice & education, aging, mild cognitive impairment, dementia, and interventions for sustaining brain function.

Anne Hunter Cox is a graduate student at Appalachian State University working towards her master's degree in Speech-Language Pathology. She earned her Bachelor of Science degree from Clemson University, where she majored in Health Science with an emphasis on health promotion and behavior. With this skill set, Anne Hunter works alongside Kim McCullough, PhD, CCC-SLP, at Appalachian State University, to provide cognitive wellness programs for adults with memory concerns in their community.

Now…read on, learn, and enjoy!

Ann W. Kummer, PhD, CCC-SLP, FASHA, 2017 ASHA Honors
Contributing Editor 

Browse the complete collection of 20Q with Ann Kummer CEU articles at www.speechpathology.com/20Q

20Q: Mild Cognitive Impairment - The SLP’s Role in Service Delivery

Learning Outcomes

After this course, readers will be able to:

• Define and describe Mild Cognitive Impairment (MCI), including the behavioral criteria for diagnosing MCI
• List the key modifiable risk factors that can reduce the risk of dementia
• Identify cognitive and language deficits associated with MCI
• Describe the role speech language pathologists have in the evaluation and treatment of MCI, including considerations for developing intervention programs to support those with MCI

Kim McCullough

Anne Hunter Cox

1. What is Mild Cognitive Impairment (MCI)?

Mild Cognitive Impairment (MCI), or Mild Neurocognitive Disorder (mildNCD), refers to the condition of a person having one or more mild cognitive deficits that are not so severe as to meet the clinical criteria for dementia (Albert et al., 2011).  The term mild cognitive impairment (MCI) historically was used to refer to the prodromal stage of Alzheimer’s disease (AD). However, many other diseases (e.g., Lewy Body disease, vascular disease)  have an early stage that also affects cognition, so the term Mild Neurocognitive Disorder (mildNCD) was coined to encompass etiologies other than AD (American Psychiatric Association, 2013). The two terms, MCI and mildNCD, are often used interchangeably. 

2. What is the prevalence of MCI?

Approximately 12% to 18% of people aged 60 or older are living with MCI. The population of Americans aged 60 and older has grown more than 30% over the past decade, and the number of older individuals in the United States is expected to increase significantly by 2050. It is estimated that 10% to 15% of individuals 65 years and older with MCI develop dementia each year (Alzheimer’s Association; Administration for Community Living, 2021). However, estimates differ because of the variability of participant ages across studies, with a higher prevalence for older adults. A community-based study of 2000 participants revealed that for individuals ages 70-89, the prevalence of MCI was approximately 16-20% (Petersen et al., 2010). The Alzheimer’s Association (2022) predicts the prevalence of dementia will triple in the next 30 years. About one-third of people with MCI due to Alzheimer's disease develop dementia within five years of diagnosis. However, it’s important to remember that not everyone with MCI will develop dementia. That being said, dementia is the third most serious health problem in the world, following cancer and cardio-cerebrovascular diseases, and the most expensive (Gauthier et al., 2022). With this in mind, MCI is of high global concern for researchers and health professionals (Bayles et al., 2020).

3. What does the public know about MCI?

According to the Alzheimer’s Association (2022), public awareness and understanding of MCI are low. In fact, more than 80% of Americans know little about or are not familiar with MCI. In addition, over 50% of all Americans say that MCI sounds like “normal aging.” Despite this lack of awareness and understanding, almost half of Americans say they worry about developing MCI. Only 40% of Americans say they would talk to their doctor right away when experiencing symptoms of MCI. More than half say they would wait until they had symptoms for a while, wait until symptoms worsened, or wait until others expressed concern before talking to their doctor.

Additionally, almost 90% of primary care providers surveyed believe it is important to diagnose MCI and that early intervention is critical, yet assessments are conducted for just half of their patients. This is not surprising since one-third (35%) of providers report they are not fully comfortable diagnosing MCI, and more than one-half (51%) are not fully comfortable diagnosing MCI due to Alzheimer’s disease. These findings underscore the need to raise the public’s awareness of MCI, while also better preparing healthcare providers to identify, diagnose and manage cognitive impairment at its earliest stages (Alzheimer’s Association, 2022).

4. What are common causes of MCI and how does it differ from typical aging?

There are many causes of MCI including neurodegenerative, vascular, metabolic, psychiatric, and traumatic etiologies. The most common cause of MCI is Alzheimer’s disease (AD). The most common symptom of MCI is episodic memory (EM) impairment. This is unsurprising given that AD is the most common cause and EM impairment is the signature AD characteristic. That being said, clinicians should be aware that AD can present in atypical ways in which memory impairment is not an early symptom. The challenge to clinicians is differentiating cognitive changes associated with pathology versus those that occur with typically aging adults. Older adults who experience changes in cognition typically have slower processing speeds, do not divide attention as efficiently as they once did, and have difficulty ordering two or more events. These adults, however, do not have an episodic memory deficit. These changes differentiate individuals with AD related MCI from healthy older adults (Bayles et al., 2020; Sabbagh et al., 2010).

5. What are the diagnostic criteria for MCI?

The four neurobehavioral criteria that define MCI (American Psychiatric Association, 2013) are as follows:

1. Concern regarding a change in cognition, compared with prior level, through self-report or the report of an informant or clinician.
2. Impairment in one or more cognitive domains that is lower than expected for the patient’s age and education.
3. Preservation of independence in functional abilities though the individual may be less efficient, prone to making errors, and need more time for task completion.
4. Not demented: The cognitive and behavioral changes are insufficient to significantly interfere with social or occupational functioning.

Although most individuals experience slight cognitive changes as they age, those with MCI often experience cognitive changes that are of concern to the individual and/or family, and have objectively confirmed impairment in one or more cognitive domains (e.g., language, or spatial/visual perception). McKhann (2011) offered that “[t]here are no exact transition points that define when an individual has progressed from the MCI phase to the dementia phase. It is a question of clinical judgment.” Individuals with MCI do not have dementia and can independently perform activities of daily living (ADLs). When ADLs are impaired, a “major neurocognitive disorder” may be considered (American Psychiatric Association, 2013).

6. What are the recognized subtypes of MCI?

Four subtypes of MCI are distinguished according to whether there is memory impairment and whether impairment exists in more than one cognitive domain. The 4 subtypes of MCI are amnestic MCI single domain, amnestic MCI multi domain, nonamnestic MCI single domain, and nonamnestic MCI multiple domain. Amnestic MCI primarily affects memory while nonamnestic MCI impacts thinking ability apart from memory such as decision making, complex task sequencing, visual perception (Mild Cognitive Impairment, n.d.). For single domain subtypes of MCI, only one cognitive function is impaired. For multiple domain subtypes of MCI, more than one cognitive function is impaired. Amnestic multidomain is the most common type of MCI. It is important to note that some individuals with MCI do not experience cognitive deterioration over time whereas others rapidly evolve to dementia. Individuals with deficits in many cognitive domains are those most likely to be in the early, prodromal stage of a dementia producing disease (Busse et al., 2006; McCullough et al., 2019).

7. What are some risk factors for MCI?

The most significant risk factor for MCI is age (Keyimu et al., 2015). Another risk is apolipoprotein (ApoE) carrier status. ApoE transports cholesterol and other types of fat in the bloodstream. Those individuals who carry this gene are at a greater risk of developing AD than those who do not. Other key risk factors that can be modified (Livingston et al., 2020) include:

• Hearing Loss
• Hypertension
• Obesity
• Alcohol Consumption
• Smoking
• Depression
• Social Isolation
• Diabetes
• Physical Inactivity
• Air Pollution

8. What cognitive deficits are commonly associated with MCI?

Changes in thinking that are likely due to MCI include difficulty in the following: immediate retrieval (episodic memory); executive functioning related to distractibility, inhibition errors, and monitoring; and prospective memory related to information to be recalled in the future. Common complaints often reported by those with MCI include (Avila-Villanueva et al., 2016; Brandt et al., 2009):

• Immediate Retrieval:
  • remembering names of people
  • remembering names of objects
  • trouble following conversations\finding it hard to follow directions
• Executive Functioning
  • difficulty focusing
  • problems in paying attention
  • trouble concentrating
  • losing train of thought
  • inability to follow the plot of a book or movie
  • difficulty making decisions or finishing a task
  • poor judgment
• Prospective Memory
  • forgetting things more often
  • missing appointments

Oftentimes, family and friends notice these changes. Additionally, many individuals with MCI may also experience higher rates of depression, anxiety, aggression,  short temper, and lack of interest in once enjoyable activities (Mayo Clinic, 2022).

9. What language deficits are commonly associated with MCI?

Language performance impairments are common among those with MCI, with language comprehension and production relying on cognition. So, the more dependent a language performance task is on memory and executive functions, the more likely it is that an impairment will be present. For individuals with MCI, verbal fluency is the most commonly reported language deficit. Individuals with MCI also show deficits in confrontation naming. Difficulties in discourse processing/production, ability to define words, and repetition skills may be present in those with MCI. When assessing older adults with cognitive concerns, performance on language subtests was more predictive of conversion to dementia than memory subtests. Research shows that deficits in language performance may appear before deficits in episodic memory, visuospatial deficits, or mental status for those at risk for MCI (Tripodis et al., 2017; McCullough et al., 2019).

10. What does ASHA say about SLPs’ scope of practice related to working with MCI?

ASHA’s Scope of Practice in Speech-Language Pathology (2016) outlines eight service delivery domains. In addition to screening, assessment, and treatment, one service delivery domain that is particularly relevant when working with individuals who are at risk for MCI or those with MCI is the “Prevention and Wellness” domain (ASHA, 2016). Prevention and wellness activities can oftentimes be woven into cognitive intervention programs. Examples of prevention and wellness activities include the following:

• Identification of disorders at an early stage.
• Decreasing the impact of a disability associated with an existing disorder.
• Enhancement/improvement of general well-being and quality of life.
• Education about modifiable risk factors that could improve function.  

11. Why is early identification of MCI important?

Early identification offers the best opportunity for better outcomes, as it can allow individuals more time to plan for the future, adopt lifestyle changes, and live more fully, with a higher quality of life, for as long as possible. Early identification is critical to early intervention. Early intervention is most effective in sustaining function and delaying the evolution to dementia. Speech-language pathologists are increasingly involved in screening individuals for MCI (in hospitals, hearing clinics, assisted living facilities, health fairs, and senior centers) and providing cognitive intervention. Most individuals with MCI reside in their communities and come to the attention of clinicians through self-report or referral from a physician or psychologist.  Many others reside in assisted living facilities and can be identified through periodic screening. 

12. What should be included in the assessment of MCI?

Testing is necessary to verify the presence and type of MCI. Standardized tests are usually required if reimbursement for services is sought. There is no gold standard for which test battery to use. However, it is important to use a test battery that has performance data for healthy peers and individuals with mild dementia. Individuals scoring one or more standard deviations below the mean of typically aging  older adults on one or more standardized cognitive tests are generally considered to have MCI. 

The selected test battery should also include language performance measures and tests that are graduated in difficulty to identify subtle impairments. Speech language pathologists are uniquely qualified to detect subtle changes in language performance. Researchers have shown that tests of language comprehension and production are particularly sensitive to early subtle deficits that occur with MCI (McCullough et al., 2019). Because changes in language function and memory are early symptoms, these functions as well as attention, visual processing, and executive function should be evaluated. The Arizona Battery for Cognitive Communication Disorders-Second Edition (ABCD-2) is a standardized cognitive-linguistic test battery with these types of tests (Bayles & Tomoeda, 2020). Importantly, each of the ABCD-2 subtests, as well as the complete battery, has been standardized on individuals with mild and moderate Alzheimer’s dementia and young and healthy older adults. Individuals with MCI typically score lower than healthy elders on one or more tests but better than individuals with mild Alzheimer’s. Those ABCD-2 subtests most sensitive to MCI are: 

• Following Commands
• Repetition (Verbal)
• Object Description
• Concept Definition 

ABCD-2 subtests can be given individually or collectively. A time-efficient way to screen for mild dementia is to administer the Story-Retelling test in both the immediate and delayed conditions. Individuals who fail the screen should be given the full battery.

Interviews should be conducted to determine the client’s leisure activities, exercise/physical activity habits, socialization, sleep patterns, medication management and side effects, and communicative function/concerns. The clinician should take time to evaluate the strengths and weaknesses in each of these areas. This information allows for a person-centered approach in developing an intervention plan that can improve skills, promote learning, and support wellness practices that encourage cognitive health (Bayles et al., 2020).

13. Are individuals with MCI good candidates for intervention?

Individuals with MCI, regardless of cause, are ideal candidates for intervention because they maintain the ability to learn and can, therefore, build cognitive reserve. Moreover, compelling evidence now exists that cognitive intervention programs produce measurable changes in the brain that are associated with enhanced cognitive reserve (Belleville & Bherer, 2012; Hampstead et al., 2018). Clinicians should be aware that cognitive intervention is also shown to benefit healthy older adults (Basak et al., 2020).

14. What is cognitive reserve?

Cognitive reserve is the brain’s ability to adapt and find alternate ways to get the job done. Cognitive reserve impacts the degree to which an individual can adapt to the effects of aging, brain injury, and disease. Cognitive reserve is built over a lifetime and those with greater cognitive reserve have extensive synaptic networks and are better able to compensate for brain damage (Bosch et al., 2010; Tucker & Stern, 2011). Several factors including brain size, level of education, and life experiences are related to the strength of one’s cognitive reserve (Riley et al., 2006). In other words, individuals with higher levels of education and more demanding careers reduce their risk of developing dementia with a greater cognitive reserve (Rouillard et al., 2017).

Cognitive reserve is neuroprotective. When comparing two individuals with the same brain pathology, those who have a more robust cognitive reserve exhibit fewer clinical symptoms (Bayles et al., 2020). Individuals may even remain symptoms free. When studying individuals with AD pathology, as shown in postmortem brain examination, research showed that 25% of these individuals were symptom free in life (Bennet et al., 2006; Neuropathology Group, 2001; Mufson et al., 2016).

15. What is neuroplasticity and how is it related to cognitive reserve?

Neuroplasticity is the basis for brain change. The brain has the capacity to learn and improve almost any function in response to stimulation. Positive changes in response to stimulation result in increased cognitive reserve (Sherman et al., 2017; Bayles et al., 2020). A study on computer-based cognitive intervention and neuroplasticity revealed that individuals with MCI maintain neuroplastic brains and can benefit from cognitive intervention programs (Cespon et al., 2018; Rosen et al., 2011). Clinicians can leverage the principles of neuroplasticity to maximize outcomes. 

16. How does cognitive intervention strengthen cognitive reserve?

Cognitive intervention increases and strengthens cognitive reserve by promoting positive brain changes. A compelling body of evidence is emerging that indicates that due to neuroplasticity and cognitive reserve, cognitive intervention for MCI can result in significant neural changes that are measurable with brain imaging and other biomarkers (Cespon et al., 2018; Belleville & Bherer, 2012; Fotuhi et al., 2016; Hampstead et al., 2018; Mufson et al., 2015). With this in mind, cognitive intervention can help sustain cognitive performance in the MCI population (Belleville et al., 2018). The American Academy of Neurology and the Alzheimer's Association both recommend that those diagnosed with MCI and their families be educated about the benefits of cognitive intervention. The World Health Organization also supports patient education with an emphasis on prevention as a major component in their public health response to dementia (World Health Organization, 2017).

17. What are the goals of intervention programs?

The ultimate goal of intervention is to improve everyday functioning (Clare et al., 2019). This can be accomplished by strengthening skills and behaviors that have the potential to improve, teaching strategies that can improve performance, and providing education about wellness practices that sustain cognitive functioning. Self-reported, or subjective, complaints often reported by those with MCI include “remembering names of people and objects, problems in paying attention, and trouble concentrating.” These inconveniences often have negative impacts on that person’s daily life. It is important to note that subjective complaints do not need to be accompanied by objective impairments to be preclinical indicators of AD and non-AD dementias (Tripodis, et al., 2017; Belleville & Bherer, 2012; Envig et al., 2010; Mufson et al., 2015). Clinicians should target both subjective and objective impairments. By taking both into account, the skills and behaviors being implemented will be more meaningful to the individual, therefore more likely to be generalized outside of the intervention program (Bayles et al., 2020).

18. What is a general framework for a cognitive intervention program? 

Program structure and content should be based on evidence-based methods for triggering neuroplasticity and building cognitive reserve to delay or prevent further loss of function. Based on the literature, cognitive programs should include multiple components that address the following focus areas: cognitive-linguistic stimulation, wellness education, opportunities for social engagement, and use of strategies that support cognitive performance (Moebs et al., 2017; Ngandu et al., 2015; Reebok et al., 2014).

19. What can I teach my client about wellness practices?

A diagnosis of MCI can be difficult to accept for both the individual and their family. It is common for these individuals to experience anxiety, fear, and low self-esteem/confidence. Some may feel as though they are losing autonomy and control of themselves (Wolinsky et al., 2009). Speech language pathologists can play a major role in assisting these individuals through their diagnosis. By teaching them about the brain’s plasticity and the impact of cognitive health and wellness on their cognitive reserve, they can reinstall a sense of control back into their lives. Learning and understanding the skills and behaviors that can promote cognitive wellness is empowering. Education topics could include: physical activity, brain healthy foods, stress reduction, trying and learning new things, and correcting sensory deficits (e.g. hearing loss) (Bayles et al., 2020).

20. What can clinicians do to promote client success?

Cognitive intervention programs vary in several aspects including topics of discussion, types of clients, client’s needs, and intensity; making it difficult to specify the duration needed to strengthen skills. Therefore, clinicians should base duration and intensity on the client’s performance outcomes. Additionally, a common sign of cognitive impairment in older adults is a decrease in social engagements and activities. Studies show that individuals who report feeling lonely and having reduced social connections have higher rates of depression, morbidity and mortality outcomes, and cognitive decline (Shankar et al., 2017; Yang et al., 2016). To address the lack of social connectedness, clinicians should consider a group therapy format. Group therapy supports social engagement and provides opportunities for authentic practice of cognitive performance strategies. In summary, the actions that clinicians can take to enhance cognitive intervention program success include: comprehensive evaluation of clients before training, involving the client in goal setting, using evidence-based therapies, tracking performance at each session, modifying treatment if improvement is not apparent, if the client is improving and the resources are available, maintain the program until goals are met, and schedule periodic booster sessions to sustain function (Bayles et al., 2020).

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