Case Study- Late Onset Moderate Alzheimer's Disease

Original Editor: Alexandra McCain

Top editors: Allegra Gracile, Christopher Nydam, Linh Nguyen

Abstract

Client Characteristics/comorbidity: Mary Johnston is an 80-year-old female diagnosed with Late-Onset Dementia Alzheimer's disease who lives alone and has been referred by her family physician to be assessed to improve balance following a fall that occurred 6-months prior causing her to require hip surgery. This fracture could have been attributed with her osteoporosis that she was diagnosed with after the fall had occurred.

Disease Phenotype/ Examination Findings: Her moderate stage, with cognitive symptoms as well as limiting physiological symptoms such as forgetfulness, irritability, and problems with gait. A complete subjective, objective analysis was collected and limitations in balance, gait speed, and strength were noticed.

Outcome measures: The outcome measures used were the BERG balance scale (BBS), the 30-second sit to stand test (30CST), and the 6 minute walking test (6 MWT).

Problem List: The problems obtained were structured around the international classification of functioning, disability and health (ICF) model and focused on the limitations in balance, gait speed, and strength.

Clinical Hypothesis/impression: The patient’s diagnosis is poor mobility and function due to general lower limb weakness along with a mild deficit in balance which is related to the LOAD diagnosis. She has a fair prognosis with physiotherapy and could benefit from it by focusing on muscle strength, aerobic endurance and walking speed to help improve ADLs, participate in social activities outside the home and maintain as much independence for as long as possible.

Intervention: Resistance strength exercises (60 minutes, 3 sets of 15 reps per exercise using a medium resistance elastic band 3 days a week for 4 months and an aerobic walking program was prescribed (45 minutes per session, 4 times a week, for 4 months at an intensity of 40% heart rate reserve (HRR) and slowly progress up to 80% HRR). As there is conflicting evidence incorporating virtual reality in the treatment of patients with moderate Alzheimer’s, there may be a benefit to including it into treatment if the technology and resources are readily available. However, there may or may not be any benefit to doing so.

Outcome: The patient had a clinically significant improvement in their BBS of 3 points. She can now perform 2 full sit-to-stand during the 30-second sit-to-stand without using her hands for support. However, we cannot conclude whether this improvement is clinically significant due to the lack of research in this population. Finally, she had no improvement in distance covered, but demonstrated an increase in confidence during the test.

Common healthcare professionals involved in care: It was recommended to refer out to an occupational therapist, neurological psychologist, and a social worker.

Introduction

Alzheimer's is a form of dementia that impacts cognitive functions such as memory, reasoning, and conduct. As the disease progresses, the symptoms become increasingly debilitating and disrupting everyday activities (What Is Alzheimer’s?, n.d.). Literature shows that multimodal exercise with a combination of resistance, aerobic, balance, flexibility around 60 minutes a day, 2-3 days a week is effective in improving various aspects of physical functioning (Lam et al., 2018). Additionally, strong evidence was found to support the use of physical exercise in improving strength, step length, balance, mobility and walking endurance for mild to moderate cognitive impairment and dementia population (Lam et al., 2018).

This case study depicts Mary Johnston, a patient with Late-onset Alzheimer’s Disease. in the moderate stage, with cognitive symptoms including forgetfulness, confusion, depression, irritability, difficulty with planning and problem-solving. Her physical symptoms include problems with gait and increased risk of falls. This case study aims to document the changes in the patient’s chief complaints throughout her participation in a 4-month physiotherapy program.

Client Characteristics

Demographic Information: Mary Johnston is an 80-year-old female who was diagnosed with Late-Onset Dementia, specifically Alzheimer’s disease (LOAD) at the age of 75. She is recently widowed and has lived alone in her 2-storey condominium for 2 years. Her adult children live nearby and visit her frequently. She finds herself becoming more frequently agitated as she is having increasing difficulty recalling objects and how to do actions (O’Sullivan, et al., 2019a). Since Mary is prone to wandering, in the past she would frequently wander out of her house. 5 months ago, during a wandering incident, she experienced a fall outside of her home and fractured her left hip. Since then, she went through a rehab program and currently uses a 1-point cane for ambulation and currently receives care from a support care worker service to help her around the house with cleaning and meal prepping, and is rarely mobilized outside of the home. She has been taking donepezil for 3 years now to assist with memory deficits and verbal learning, but has only noticed a slight improvement in symptoms (O’Sullivan, et al., 2019b).

Disease Phenotype: Mary's Alzheimer's disease is a late-onset form of dementia due to Alzheimer’s (LOAD). It is in the moderate stage, with cognitive symptoms including forgetfulness, confusion, depression, irritability, difficulty with planning and problem-solving. Physical symptoms include problems with gait and increased risk of falls.  She also experiences occasional disorientation as she is prone to wandering outside of her own home.

Examination Findings

Subjective:

• Has difficulties remembering what she did on the weekends, conversations, and names of people
• Gets confused about where she is or how she arrived to certain places
• She has troubles expressing herself verbally and emotionally
• She becomes frustrated, anxious, and depressed based on her inability to recall information and/or complete tasks of daily living
• Struggles to complete daily grooming tasks and cooking her own meals
• Wanders often and gets lost easily
• Has issues keeping her balance and holds onto objects around the house while ambulating (walls, furniture, etc.)
• Pain VAS: 1/10 at rest in the left hip, with gait: 3/10.
• Precautions/Contraindications: short term memory with confusion in occasions, risk of agitation.

Observation:

• Exaggerated kyphosis in the thoracic spine → rounded back
• Forward head posture.
• Difficulty with fine motor skills including pen holding when filling out a form.
• Slight disorientation & confusion at times during assessment.
• While standing, stands with a wide base of support

AROM:

• Limited IR and ER in the shoulder
• Limited Shoulder flexion bilaterally.
• Limited left hip extension and abduction.
• Limited knee flexion
• All other ROM is within normal limits.

PROM:

• Limited left hip extension and abduction
• All other joints within functional ranges.
• Normal tone

Resisted Muscle Testing (MMT):

Hip Extension	Hip abduction	Knee flexion	Knee extension	Ankle Plantarflexion	Ankle dorsiflexion
L: 3/5 R: 3+/5	L: 3/5 R: 3+/5	L: 3+/5 R: 4-/5	L: 3+/5 R: 4-/5	L: 4-/5 R: 4-/5	L: 3- R: 3

Coordination Tests:

• Finger to nose: symmetrical and smooth bilaterally
• Heel to shin: symmetrical and smooth bilaterally
• Alternate movement of hands & feet: symmetrical and able to increase speed.

Respiratory function:

• Respiratory rate: 19 bpm
• Apical breathing pattern observed
• Modified borg RPE
  • At rest: 1/10
  • With exertion: 3/10
• Dyspnea scale
  • At rest: 0/10
  • With exertion : 2/10

Outcome measures:

• BERG balance test: Final score of 38/56
• 30-second Sit to Stand: Score 0 due to the need to use her arm while performing the test.
• 6 MWT: She covered 160 m in 6 minutes using a one-point cane.

Gait:

• Tested with the use of a gait aid (single-point cane)
• Slower gait speed of 0.61 m/s
• Decreased stride length
• Normal cadence
• Wide base of support
• Decreased arm swing
• Forward leaning posture

Comorbidity - Osteoporosis: Comorbidity is defined as the presence of more than one distinct condition in an individual (Valderas et al., 2009). Although there is no direct causal relationship between late-onset Alzheimer’s disease and osteoporosis, it is quite common to have both due to the lack of mobility and lower accumulation of exercise in people with LOAD, thus increasing the likelihood of developing osteoporosis. Additionally, Mary is a 75-year-old woman who has undergone the normal changes that occur as a result of menopause. Menopause causes hormonal changes, specifically a rapid decrease in estrogen which normally helps maintain bone density (Cauley et al., 1995). Osteoporosis would be a large contributing factor to the fracture of Mary’s hip when she fell outside.

Problem List

1. Body Structure and Function: Mary has poor gait and balance due to reduced activity levels, poor cognition and attention.
2. Activity Limitations: Due to her lack of lower extremity muscular endurance and strength, Mary has difficulty with activities of daily living such as dressing, grooming, and preparing meals. Specifically, standing for long periods of time to shower, as well as preparing meals.
3. Participation Restrictions: Mary feels socially isolated and has limited ability to participate in bingo. This is due to her inability to maintain attention and dual task to ambulate in a safe and effective way to cross the major intersection at Senior Centre.

Clinical Hypothesis/Impression

Physiotherapy Diagnosis: Mary's physiotherapy diagnosis is poor mobility and function due to general lower limb weakness along with a mild deficit in balance which is related to the LOAD diagnosis.

Prognosis: Mary has a fair prognosis due to the progressive nature of her primary diagnosis of LOAD. Mary has the finances to afford to pay for support and physiotherapy treatment, as well as has close family support when needed. The family has already been able to adapt the home environment to Mary’s needs so that she can continue living at home. However, she recently experienced a fall and a fracture while out in the community, putting her at risk for decreased mobility status and atrophy. Additionally, she has cognitive issues affecting her memory, mood and activity of daily living (ADLs), which may impact the effectiveness of physiotherapy treatment.

Based on these factors, she could still benefit from physiotherapy by focusing on muscle strength, aerobic endurance and walking speed to help improve ADLs, participate in social activities outside the home and maintain as much independence for as long as possible. Referrals out to occupational therapy, neuropsychology, and a social worker could all assist in the holistic treatment of her condition. Although Mary’s condition has developed into a moderate cognitive decline, there are many things she can still participate in to slow the progression of the disease.

Intervention

Identified smart goals:

1. Decreased balance:
   • Short-term goal: Mary will be provided with strengthening exercises to enable her to balance on one leg to improve her BERG score to reduce risk of falls and subsequent injury within four wee
   • Long-term goal: Mary will increase her overall score using the BERG Balance Scale by five points (to reach minimal detectable change) through a variety of balance and strengthening exercises provided by and progressed with the physical therapist within four months.
2. Difficulties with bADLs specifically, grooming due to lack of muscle strength
   • Short-term goal: Through a prescribed muscular strengthening program, Mary will increase her lower limb strength and endurance to foster confidence towards independence of bADLs, specifically self-grooming tasks within four weeks.
   • Long-term goal: Mary will continue to work on strengthening exercises focused on static loading to develop the endurance required to prepare her own meals in a timely manner, thus reducing the stress that Mary feels while cooking and reducing her care-giver burden within four months.
3. Lowered participation rates of Bingo at the Senior’s Center
   • Short-term goal: Improve Mary’s gait speed through gait specific exercises as measured through the 6MWT, thus improving Mary’s mobility and ability to travel to the Senior’s Center for Bingo, within four weeks.
   • Long-term goal: Improve Mary’s confidence to participate in Bingo at the Senior’s Center through combining exercises related to gait to improve her speed, thus increasing her likelihood to engage in Bingo night within four months.

The intervention program that would be assigned to Mary is a resistance strength exercise program of both upper and lower body for 60 minutes, 3 sets of 15 reps per exercise (which targets the chest, biceps, triceps, shoulder, knee extensors, abductor and adductor muscles, and calf muscles) with an elastic band of a medium resistance level for three days a week for four months (Lam et al., 2018)(López-Ortiz et al., 2021).

We would also give her an aerobic walking exercise program that is 45 minutes per session, four times a week, for four months. She would be instructed to walk at an intensity of 40% of her heart rate reserve (HRR) (this would be educated to her as walking at a moderate intensity) and we would slowly progress her up to 80% HRR as she progressed (Lam et al., 2018). This exercise could be conducted on a treadmill to ensure a safe environment.

The resistance strength exercise has been shown to not only increase the participants’ strength, but also improve participants’ balance (Lam et al., 2018). Thus, this portion of the exercise program would target both the goal to improve Mary’s balance as well as improve her strength so that she can safely and effectively shower and perform other bADLs. The aerobic exercise was included to target Mary’s walking speed so that she can participate in her bingo activities.

Innovative Technology-mediated tools to enhance the approach to intervention:

As indicated through the case-study, balance issues can be a main physiotherapy problem associated with those with mild to moderate Alzheimer’s onset Dementia (AD) (Suttanon et al., 2012). Especially since those diagnosed with AD are at a higher risk for falls and resulting hip fractures, further increasing their dependence on others for ADLs and mobilization (Weller & Schatzker, 2004). Thus, balance training should be an important factor in physical therapy for those with a LOAD diagnosis. Specific innovative technology that can be implemented to supplement traditional balance training is virtual reality (VR). VR can be implemented in a variety of different ways, but can be differentiated by the level of immersion provided by the technology. The categories include: low immersion, semi-immersive, and fully-immersive (Zhu et al., 2021). Low immersion typically involves a more simple set-up, including a mouse and keyboard (Zhu et al., 2021). Semi-immersive implements more sensory feedback elements, such as haptic gloves, a motion tracking, and a balancing platform (Zhu et al., 2021). Finally, a fully-immersive system may involve a head mount and surround screen, along with other sensory feedback systems to create an immersive environment (Zhu et al., 2021).

A systematic review and meta-analysis completed by Zhu et al., 2021 analyzed the effectiveness of VR on cognition, balance and gait for those with a mild cognitive impairment and Alzheimer’s dementia. This study determined that VR had a moderate effect size on cognition and motor function overall, but did not have a significant effect on visuospatial ability or gait. Additionally, VR had a significant impact on those with a mild cognitive impairment versus a non-significant impact on those with AD, suggesting that moderate to severe cognitive impairment associated with AD may inhibit the positive effects of VR on balance. Thus, it would be ideal to implement VR balance training in those who are at risk of developing AD progressed from a MCI. Finally, this study found that semi-immersive or fully-immersive VR is more effective than low-immersive VR. Another systematic review completed by Yi et al., 2022 confirmed these results, echoing that moderate-immersive VR improves body balance in those with AD. Therefore, due to the conflicting evidence of the effectiveness of VR in those with moderate AD, supplementing traditional physiotherapy treatment with VR may be beneficial, provided that the resources are available and the patient can tolerate it well.

VR may be an effective approach as it involves both immersive and interactive components (Zhu et al., 2021). Immersion of a patient in a virtual reality environment acts as a safer method to performing rehabilitation exercises in the community, along with the added ability of providing multiple forms of sensory feedback through external equipment to replicate a real-world environment (Zhu et al., 2021). This has been demonstrated physiologically through increased EMG in the right arm while participants observed a virtual arm made to move with the person’s body, and through an increase in heart rate to the virtual projected hole in the ground (Meehan et al., 2005; Slater et al., 2008).

As mentioned earlier, semi or fully-immersive VR proved to be the most effective on balance, but both of these methods require a lot of equipment. So, instead of utilizing 360 screens and head mounts, it would be ideal to use similar commercial products that the clinic can ideally get for a lower price. Some examples include video-game consoles like the Wii, the Oculus Rift, or the Xbox Kinect system. The advantages of these systems is that they come with external devices, like a balance platform, a head mount, or a camera to track body movements to help with immersion into the VR. Additionally, some of these consoles can be paired with games that allow for the patient to perform goal-oriented activities to work towards body balance, one example being the Wii Fit game associated with the Wii Console. Studies done by Padala et al., 2012 and Liao et al., 2019 are examples of studies demonstrating the effectiveness of commercialized products.

Finally, patients who have not had a lot of experience utilizing VR headsets or playing video-games may experience motion-sickness while completing VR treatment. This is not ideal as this may discourage patients from wanting to participate in VR treatment in future sessions, even if they are seeing results. One way to mitigate this is to split up the duration of a session into small parts. Sessions in studies reviewed by Zhu et al., 2021 ranged from 20-90 minutes, thus, splitting up a 60 minute session into 3 parts (20 minutes per session) will allow for the beneficial effects to be maintained while allowing for breaks. Additionally, utilizing semi-immersive VR instead of fully-immersive VR may be more beneficial for reducing motion sickness.

Outcome

Berg Balance Scale (BBS) is a tool to assess balance and fall risk which addresses the first problem regarding Mary’s poor balance. There is an excellent test-retest and relative inter-rater reliability of the BBS in a population of nursing home residents with mild-to-moderate dementia (Telenius et al, 2015). Minimal Detectable Change is 1.92 points. It has an excellent internal consistency.

30-second sit-to-stand test (30CTS) is a measurement assessing functional lower extremity strength in older adults to address Mary’s lack of lower extremity muscular strength. According to Jones et al (1999), the 30CTS has an excellent test-retest reliability and interrater reliability. It also has an excellent criterion validity compared to weight adjusted leg press (Jones et al, 1999)

6-minute Walk Test (6MWT) is a tool to assess gait and gait speed which is important to measure and address Mary’s slow speed of ambulation. In a study by Ries et al (2009), the 6MWT is shown to have excellent test-retest reliability, interrater and intrarater reliability for populations that have Alzheimer’s Disease. Minimal detectable change of this outcome measure is 33.47 meters (Ries et al, 2009) It also has adequate concurrent validity with sit-to-stand, standing balance and gait speed (Harada et al, 1999)

Following Mary’s initial assessment, it was determined that she would receive four months of physiotherapy care at home to address her lower body strength, balance and gait speed deficits. After the first four weeks, there were little changes in Mary’s functional status. It actually gave her some light discomfort such as muscle soreness. However, after 4 months of following an aerobic walking and a resistance exercise program, Mary’s main functional status including lower body muscle strength, balance and her speed of gait has changed despite still having some problems with cognition issues or memories. According to the Berg Balance Scale administered after the treatment program, her score improved from 38 to 41/56. This indicates she is still at greater risk of falling, but her score is shown to be clinically significant improvement (Berg, 1992). Additionally, she can now perform 2 full sit-to-stand during the 30-second sit-to-stand without using her hands for support, which indicates that she is currently below average (Rikli and Jones, 1999). A conclusion cannot be made on whether this is a clinically significant improvement due to the lack of research on this population. Finally, she had no improvement in distance covered, but demonstrated an increase in confidence during the test. Based on her progress and improvements over the past four months Mary should continue physiotherapy treatment as needed to help manage the progression of the musculoskeletal, postural, and gait impairments secondary to LOAD.

A few adverse effects of this exercise program could be falling, increased fatigue, headaches and experiencing an increase of pain (Faieta et al., 2021; Henley et al., 2015). If there was an adverse event with the patient, the exercise program could be adapted in a few ways. Firstly, to reduce falls risk, we could recommend that the patient could perform aerobic exercise on a treadmill to ensure a safe environment and to reduce risk of falls when exercising if they have the means to do so. However, if they do not have the resources or funds to use a treadmill, Mary could do standing marches and progress up to walking as she progresses. If the intensity of the program were to be too much for the patient, we would lower the total minutes of exercise to 30 minutes per program, as this time was still shown to have a significant improvement for participants post-exercise program (Lam et al., 2018). As well, we would reduce the HHR of the aerobic exercise back down to 40% until she could build back up her tolerance for exercise, and both the strengthening and aerobic protocol could be reduced to 2x/week if needed and still have a significant effect on the patient’s outcomes (Lam et al., 2018).

Common healthcare professionals involved in care:

1. Occupational Therapists: provide everyday tools and strategies for improving independence and completing bADLs and iADLs.
2. Neuropsychologist: can prescribe pharmaceuticals and provide other ways to treat common psychological conditions that are typically seen in people with LOAD such as anxiety and depression.
3. Social workers: can provide assistance with bADLs and education for outsourcing common care-giver duties to family members and people close to Mary. They can also provide emotional support when Mary is struggling to cope with her mental health.

Referral Note - Occupational Therapist:

Hello, our physiotherapy team has recently assessed an 80-year-old female, named Mary Johnston who had been diagnosed with Late-Onset Alzheimer’s Disease (LOAD) and has been living with it for the last five years. Our treatment plan includes whole body strengthening and balance exercises. However, in addition to her weakened physical state, she has also been struggling to cope with her disease and finds her lack of independence very disheartening. Because of this, she struggles to keep up with her bADLs (specifically grooming and meal preparation) and has recognized a reduction in participation of certain iADLs (specifically participation of Bingo at the Senior’s Center). Mary lives alone in a two-storey condominium. However, she has children that live nearby who visit her frequently. Areas of improvement that we have identified thus far that may be helpful to know prior to assessment include: deficits in cognitive abilities, memory, attention, and decreased feelings of well-being causing social isolation and depression. We would like to refer Mary for occupational therapy services to be used in conjunction with our treatment to identify goals and provide strategies to assist and educate Mary’s on improving her independence and participation in such tasks.

Discussion

People diagnosed with Late-Onset Alzheimer’s Disease (LOAD) face many challenges that must be addressed through an interdisciplinary team of health care professionals. As physiotherapists our scope of practice aims to improve a patient’s mobility, function, and quality of life through interventions related to modalities, manual therapy, and exercise prescription. These troubles are only a fraction of what people with LOAD struggle with on a daily basis. In addition to deficits in mobility and exercise adherence, People with LOAD have negative effects on memory, thinking, and behaviours. It is important to consider these declines in cognition in people with LOAD and to refer out appropriately. In addition to physiotherapy, a common health-care team required when treating people with LOAD would commonly include an occupational therapist, neuropsychologist, and a social worker. Each member of the team will provide distinct treatment and care that would benefit a person diagnosed with LOAD. In addition to the interdisciplinary health-care team, education provided to care-givers and family members can be extremely beneficial in reducing the day-to-day burden of care that people with LOAD feel.

In conclusion, people with LOAD need a multidisciplinary team of healthcare professionals, each with individualized goals to help facilitate the maintenance of function, and provide strategies to reduce the burden-of-care that people with LOAD experience. Communication between the team as well as other care-givers such as family members is absolutely necessary to provide optimal care in people with LOAD.

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