Clinical Assessment of Memory Impairment

Symptom questionnaires

Assessment of memory and cognitive function

• The Mini Mental State Examination (MMSE) Mini-Mental State Examination (Mmse) for the Detection of Alzheimer's Disease and other Dementias in People with Mild Cognitive Impairment (Mci) is a brief test that measures intellectual memory and cognitive function. It is used to detect a more advanced stage of a memory disease where the ability to function normally on a day-to-day basis has deteriorated. It is not suited for screening early subtle memory losses. It should be noted, however, that the patient's level of education or linguistic problems can influence the test results.
• More sensitive screening tools than the MMSE test are cognitive test batteries, such as the CERAD behaviour rating scale and the Montreal Cognitive Assessment (MoCA) http://www.mocatest.org/ Montreal Cognitive Assessment for the Diagnosis of Alzheimer's Disease and other Dementias.
• For the evaluation of cognitive functioning, a more comprehensive neuropsychological examination is recommended Neuropsychological Disorders.
  • Specific indications for the examination include an evaluation of work capacity, assessment of rehabilitation needs, problems in the differential diagnosis (specific disorders, depression), as well as an assessment of legal competence in problem situations. It is often indicated in skilled patients and in patients in working age.
• In mild and incipient disorders, repeating the examination in 6-12 months often helps to establish the diagnosis.

Typical earliest findings in progressive memory diseases

• Alzheimer's disease: progressive impairment of episodic memory
• Vascular cognitive impairment: weakening of executive function, walking difficulties (apractic walking), balance disturbance
• Lewy body disease: disturbances in the regulation of attention and alertness and in executive function, visual perception disturbances, visual hallucinations and extrapyramidal findings
• Frontotemporal lobar degenerations: behavioural symptoms, impaired executive function and language problems
• Normal-pressure hydrocephalus: frontal lobe originating symptoms, walking apraxia, difficulty in holding urine

Assessment of functional independence and coping with everyday activities

• The daily activities to be assessed are washing, feeding, dressing, transferring, toileting and continence (BADL - Basic Activities of Daily Living). More complex activities (IADL - Instrumental Activities of Daily Living) include the ability to use the telephone, shopping, food preparation, housekeeping, ability to travel independently, responsibility for own medications and the ability to handle finances. Various short tests have been developed for the assessment of BADLs and IADLs Assessment of Functional Capacity in the Elderly.
• An assessment of functional independence is often based on interviews with the patient and a family member as well as on reports from providers of home help services and home nursing care.

Assessment of mood and behavioural symptoms

• Depression can be identified by interviewing and observing the patient. Occasionally in depression, a depressed mood is not apparent but the patient presents with a decline in memory and cognitive function or physical symptoms. In such cases, depression can be diagnosed only through trial treatment and monitoring.
• Depression rating scales include, for example, the Geriatric Depression Scale (GDS) and the Cornell Scale for Depression.
• In addition to depression, attention should be paid to anxiety, psychotic symptoms, restlessness and other possible forms of abnormal behaviour and personality changes. In unclear cases the patient should be sent for a psychiatric examination.

Assessment of disease severity

• Tools used to assess the severity of a progressive memory disease include the Clinical Dementia Rating (CDR) and GDS-FAST staging systems.

General and neurological status

• Normal neurological status is common at the early stages of Alzheimer's disease Alzheimer's Disease.
• Unilateral symptoms (weakness on one side, abnormal pronator drift test, increased tendon reflexes), and bulbar findings (dysarthria, dysphagia, compulsive crying and laughter), as well as extrapyramidal symptoms (increased muscle tone, short-step gait) are indications of vascular dementias Vascular Cognitive Impairment (Vci).
• Extrapyramidal symptoms, frequently accompanied by tremor, are indicative of Parkinson's disease. Extrapyramidal symptoms are often also seen in Lewy body dementia Parkinson's Disease Dementia and Dementia with Lewy Bodies.
• Apraxic gait is an indication of normal-pressure hydrocephalus or small vessel disease of the brain.
• Myoclonus, frequently in connection with other abnormal findings on clinical examination, is an indication of Creutzfeldt-Jakob disease Uncommon Infections of the Central Nervous System.
• Involuntary movements indicate Huntington's disease. These are also often seen in patients with Parkinson's disease receiving drug treatment.

Laboratory tests

• Basic blood count with platelets, glucose, plasma sodium, potassium, calcium, thyroid, liver, and kidney function tests, vitamin B₁₂ and, if considered necessary, lipids and ESR
• ECG, particularly if the introduction of acetylcholinesterase inhibitors is considered
• When suspecting Alzheimer's disease, examining cerebrospinal fluid markers (beta-amyloid 42 and tau and/or phospho-tau protein) may be considered, but this is not always necessary if the diagnosis is reached otherwise.
• Further tests after individual consideration: e.g. syphilis serology (Treponema pallidum antibody test or Treponema pallidum haemagglutination assay), HIV and Borrelia antibodies, drug screen.

Brain imaging

• Magnetic resonance imaging (memory MRI) of the brain is the first-line investigation when features characteristic of memory diseases are to be demonstrated.
• CT scanning (memory CT) can be carried out if an MRI scan is contraindicated (sometimes pacemaker, other ferromagnetic foreign bodies, claustrophobia) or imaging needs to be done urgently (e.g. a suspicion of trauma).
• The most important treatable causes, such as a subdural bleed, normal-pressure hydrocephalus and tumours, can be demonstrated with a CT scan as can changes caused by a cerebrovascular disease, such as signs of infarcts and moderate to severe white matter low-density areas.