Dementia is a neurodegenerative disorder characterised by a decline in cognition, affecting two or more of the following domains: the ability to store and remember new information (learning and memory); language functions; reasoning, judgment and performing complex tasks (executive functioning); perceiving and processing spatial information; behaviour and personality. The decline in cognitive functioning interferes with daily functioning and cannot be explained by a delirium or depression.
The most common form of dementia in older adults is Alzheimer’s disease (AD). The hypothesis is that it is caused by beta-amyloid plaques in the brain which disturb the communication between braincells. MRI imaging shows atrophic changes in the hippocampus to begin with, followed by changes throughout the cortex. Alzheimer’s disease typically progresses slowly, over months and years and the most common symptom is memory problems. Language issues, executive functioning and orientation problems also commonly exist in this disease. The second most common form of dementia is vascular dementia due to cerebrovascular damage. Because both small and large vessels can be affected, symptoms can vary and fluctuate widely. In elderly patients, mixtures of AD and vascular dementia are not uncommon. Rarer causes of dementia are Lewy body dementia and frontotemporal dementia.
Mild cognitive impairment (MCI) is a state in which someone might have (objective) cognitive impairments but preserved daily functioning. Some subtle changes in cognition may occur in normal ageing. MCI can be a precursor to dementia but, in over 50% of patients, this is not the case. It is not possible to reliably predict which patients with MCI will develop dementia.
The diagnostic process can be performed by the GP or in consultation with a geriatric specialist, if needed. Hetero-anamnesis is essential but the diagnosis cannot be established without repeated consultations with the patient themselves. Diagnosis requires objective assessment of cognitive functioning. Commonly used instruments are the Mini Mental State Examination (MMSE) and the clock drawing test. The RUDAS test may also be considered. Physical examination is aimed at signs indicative of dementia (e.g. head turning sign, actions during dressing and undressing, recognition of objects in the room; pay attention to a patient’s personal care) and / or signs of other causes for memory problems (delirium, depression, psychosis, subdural haemorrhage). More extensive (neurologic) investigation and blood tests are performed on indication. Routine imaging is not recommended.
Providing information about the diagnosis and prognosis to the patient and their caregivers is important once dementia is diagnosed. Case-management and personal guidance to the patient and caregivers should be offered. In the Netherlands, dementia case-managers are regionally available. The effects of non-medicamental therapy, such as occupational or movement therapy are uncertain but these therapies may improve the patients’ daily routine and wellbeing. Day-care and other non-medicamental options may also be supportive to a patient’s caregivers. Part of the education offered to patients and their caregivers may be to explain that treatment with anticholinesterases is not effective. An individual care plan can help clarify and prioritise problems. It can also help to get an overview on the (in)formal caregivers involved and align actions.
Referral may be helpful in case of diagnostic uncertainty (e.g. symptoms at a younger age or a suspected rare cause of dementia), in case of (psychiatric) comorbidity, problematic behaviour or in case of legal incapacity and involuntary care.