Managing dementia in primary care
Associate Professor Reshma A Merchant, Head & Senior Consultant of the Division of Geriatric Medicine at the National University Hospital, Singapore, speaks with Audrey Abella to discuss the challenges associated with dementia, its impact on the ageing population, and how this condition can be best managed in primary care.
Dementia is an evolving chronic disease and is the greatest global challenge for health and social care in the ageing population. The global cost of dementia was estimated to be US$ 818 B in 2015, with nearly 85 percent of costs related to family and social care. Globally, about 47 million people were living with dementia in 2015, and this is expected to triple by 2050. In Singapore, the Well-being of the Singapore Elderly (WiSE) study conducted in 2013 and spearheaded by the Institute of Mental Health reported a 10-percent prevalence of dementia in adults aged >60 years.
Age is a significant predictor of dementia. Compared with adults aged 60–74 years, the likelihood of dementia is 4.3 and 18.4 times higher than those aged 75–84 and ≥85 years, respectively. Seniors with dementia will gradually lose their functional abilities and have personality change, with up to 90 percent developing behavioural and psychological symptoms of dementia (BPSD).
Derived from the Latin word de (out of) and mens (mind), dementia has created a stigma in certain cultures, compelling people to avoid the diagnosis. In the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the word dementia has been replaced with “major neurocognitive disorders”, which comprise illnesses with demonstrable neural substrate abnormalities together with cognitive symptoms occurring in people who have had normal brain development.
Three important pointers
1. There is no cure for dementia. However, dementia may be preventable. Early diagnosis may help delay its progression and subsequent disabilities.
2. Undiagnosed dementia is associated with poor compliance to treatment and management, eg, poor diabetes mellitus control, which will accelerate progression of memory decline.
3. Caregivers should be involved in decision-making (eg, lasting power of attorney [LPA], chronic disease management, medication compliance, etc) with patient’s permission.
Dementia is a form of brain degeneration characterized by the loss of neurological function (clinically) and neurons (pathologically). Cells that produce acetylcholine, which is necessary in the formation of memory and learning, are either damaged or destroyed thereby reducing the amount of acetylcholine necessary to carry chemical messages across neurons.
Causes of dementia
Dementia is another layman’s term for ‘brain failure’ and like heart failure, there are several causes of dementia.
· Alzheimer’s disease (AD), one of the many causes (and most common) of dementia, exhibits three major features: neurofibrillary tangles, amyloid plaques, and granulovacuolar degeneration.
· Vascular dementia typically entails a history of prior cerebrovascular accident. Patients usually have a stable functional trajectory unless they suffer from another stroke.
· Other common forms of dementia:
- Dementia with Lewy bodies (DLB)
- Frontotemporal dementia
- Dementia associated with brain injury, infection, and alcohol abuse.
Among adults aged >80 years, mixed dementia (ie, Alzheimer’s and vascular), is more common.
A multicentre, longitudinal study on 1,036 AD patients conducted by the Consortium to Establish a Registry for Alzheimer’s disease in the US demonstrated a median duration of survival of 5.7 and 7.2 years for men and women, respectively. Survival is very much dependent on the stage of diagnosis. For those diagnosed and started on acetylcholinesterase (AChE) treatment early, survival can be as long as 14–16 years depending on the age of onset and other underlying comorbidities.
Several studies revealed that cognitive impairment remains unrecognized in 27–81 percent of affected patients in primary care. Caring for patients with dementia is associated with significant caregiver stress especially in the later stages wherein they become bedridden with feeding difficulties.
Despite the lack of cure, there are interventions that can transform the lives of afflicted individuals and their families, which maximize cognition, decrease caregiver stress, and improve quality of life for both caregivers and patients.
A timely diagnosis will enable pharmacological, social, environmental, and psychological interventions that can assist in reducing agitation, depression, troublesome psychotic symptoms, and institutionalisation, and maintain functional status for a longer period.
There are many symptoms which suggest the need for further assessment including decreased ability to learn or retain new information, difficulty handling complex tasks, diminished reasoning ability, getting lost and having problems with orientation, behavioural and personality changes, and diminished language ability.
Other subtle symptoms include poor compliance to treatment and repeated health-seeking behaviour for the same issues (eg, dizziness, chest pain). At times, symptoms become more apparent when there is a change of environment (eg, new home) or loss of a loved one who may have been managing the situation without other family members’ knowledge.
Diagnosis carries numerous implications and should only be made after a comprehensive assessment including history taking (from both patient and informant), cognitive and mental state examination, and physical examination to evaluate for tremors or focal neurology. A review of medications is very important as many drugs with anticholinergic properties (eg, muscle relaxants or cough and cold medications) can worsen memory.
Important features to note in the history include short-term memory loss and good long-term memory, impact on work and family, complications, and family history of dementia.
When a patient or family member reports forgetfulness, it is crucial to use a four-step assessment to evaluate the cognitive complaint:
1. Is the forgetfulness or confusion acute or chronic? If acute, it is important to rule out delirium, and a relatively early appointment with a geriatrician is necessary if no cause is identified.
2. If the forgetfulness is chronic, is it dementia?
3. If it is dementia, what are the complications (eg, BPSD, depression, driving)
4. If it is dementia, what is the aetiology? Certain types of dementia may have a shorter life expectancy. In addition, for those diagnosed with DLB, neuroleptics or antipsychotics should be avoided.
Individuals diagnosed with dementia should be asked if they wish to know their diagnosis and if any other family members should be involved in the discussion.
Formal testing should be carried out using standardized instruments such as the Chinese Mini-Mental State Examination (cMMSE) and Montreal Cognitive Assessment (MoCA). Interpretation should consider language preference, hearing and vision impairment, age, depression, and education level.
Patients who are depressed may also score inappropriately low. Referral to specialists (ie, psychiatrist, geriatricians, neurologists) may be warranted in cases of borderline or questionable dementia requiring a formal neuropsychological assessment and neuroimaging.
There are three stages of deterioration in dementia – mild, moderate, and severe. Each phase presents with different types of BPSD symptoms with progressive decline in functional and cognitive abilities.
Individuals with mild dementia can independently perform activities of daily living (ADL) but display personality changes with paranoia and may need assistance with medication compliance and major financial management. Depression is not uncommon as they may have some insight that they are losing their memory.
For moderate cases, individuals may exhibit hallucinations, delusions, agitation, and gradually declining capacity to perform ADL. Previously, patients were referred for evaluation at this stage with relatively shorter life expectancy. However, in the last 2 years, many patients are being diagnosed at the very early stage due to greater awareness by family members.
Tests to confirm diagnosis
Diagnosis requires a good history supported by cognitive screening tests. Specific tests are necessary to rule out reversible or treatable causes of dementia, which include depression, space-occupying lesions, normal pressure hydrocephalus, B12/folate deficiency, endocrine causes (eg, Addison’s disease), uraemia, recurrent hypoglycaemia, infections (eg, tuberculosis, HIV, syphilis, vasculitis), and chronic intoxications (eg, metals/drugs).
A basic screen should be performed at the time of presentation, guided by history and physical examination. The common tests include thyroid function tests, as well as those evaluating calcium, glucose, vitamin B12, and folate levels.
Serology test for syphilis and HIV should not be a routine investigation in patients with suspected dementia. These should be reserved for those at risk based on clinical history. Additional tests may be necessary to rule out reversible causes as noted in the medical history.
Structural imaging should be used, though not always, for evaluating suspected dementia to rule out other cerebral pathologies and help establish the type of dementia. For very early or borderline cases, MRI is the preferred modality; CT brain scans may be used as well. Imaging may not always be needed in moderate to severe cases especially if the diagnosis is clear cut.
[Image courtesy of www.npcfund.org]
Coronal MRI scan shows absence (left) and presence (right) of atrophy of the medial temporal lobe in a healthy elderly subject and a patient with AD.
Diagnosing dementia is heavily dependent on history and could be challenging and difficult for healthcare professionals for several reasons:
1. People with dementia who still have insight into their issues are often in denial and can get agitated during history taking and may require multiple consults and trust building;
2. Family members may not be staying with them to give a full accurate history. In many instances, family members attribute the forgetfulness to normal ageing.
Therefore, healthcare professionals may need a longer time to assess and discuss the diagnosis and its implications with patients and their family members, who need ongoing support to cope with difficulties at different stages of the disease.
Even as a geriatrician, diagnosis is not always straightforward. History from family members who spend the most time with them is crucial to evaluate impairments in short-term memory, instrumental activities or ADL, and duration of impairment.
Patients presenting in the moderate or advanced stages with >4-year history is often straightforward. For those presenting at the very early stage, family members are usually more concerned than the patient. Multiple consults might be necessary to build trust and perform cognitive tests. Discussion on driving and safety is also often difficult.
To guide in the diagnosis, clinicians may refer to the recently revised NICE UK guidelines. Although local guidelines have not been updated, some parts may still be relevant. Other tools that can help GPs manage dementia are the Clinical Diagnostic Rating (CDR) or MMSE to evaluate for progression.
There are several treatments available that may delay disease progression especially if started early. Treatment goals include reducing injury, caregiver stress or burnout, and premature institutionalization, and preventing BPSD.
Currently, there are two groups of medications used for managing dementia:
1. AChE inhibitors (eg, donepezil and rivastigmine), which are recommended for mild to severe AD; and
2. Memantine, an N-methyl D-aspartate receptor inhibitor, which is recommended for moderate to advanced stages. Memantine can be used either alone or in combination with AChE inhibitors especially for those who are intolerant to AChE inhibitors.
Factors to consider when initiating cognitive enhancers include the stage of dementia, patient’s clinical profile, expected benefit, side effects, comorbidities, and affordability.
It is also important to alert patients on the possible side effects of AChE inhibitors (ie, nausea, dizziness, loss of appetite, bradycardia). For gastrointestinal side effects, these are mostly minimized if taken with meals or by using a rivastigmine patch.
Challenges in treatment:
1. Treatment is not a cure.
2. Treatment may not alter the underlying degenerative process.
3. Treatment can be considered successful if symptoms are slightly improved, unchanged (which could have otherwise worsened), or slightly worst but better than accepted if no treatment.
Patients should be made aware in case new drugs need to be introduced to help with their forgetfulness and help them think better. Although treatment may not provide cure, it could enable patients to remain stable for longer or provide slight improvement.
Every patient with dementia is different with different comorbidities, complications, family dynamics, caregiving coping abilities, and overall decline. While reading on dementia may sound straightforward, it may seem difficult when confronted with a patient. Nonetheless, it could get better with time and experience. Supporting patients with dementia and their caregivers is crucial during the entire journey.
Treatment and care should be tailored according to patients’ needs and preferences. Patients should be given the opportunity to make informed choices about their care, and treatment must be supported by healthcare professionals. LPA should be encouraged if patients still have the capacity. Primary care physicians need to be determined about prevention as there is no cure for dementia.