Distinguishing between forgetfulness related to depression/anxiety, MCI or mild dementia can be a challenge, and therefore any concern about a decline in cognition requires careful evaluation. Although the history should be taken from the patient where possible, it is imperative that information is also obtained from a close family member or friend who knows the patient well. Subtle changes may otherwise be missed. Sometimes the physician may note telltale signs of cognitive impairment, such as the patient having difficulty following instructions, unexplained missed appointments, lost prescriptions or poor control of diabetes, hypertension or other chronic conditions.
Key points to obtain from the history include:
- details of the memory complaint, such as
- onset (When was it first noticed? Was the onset abrupt or insidious?)
- course (Has it been stable, deteriorating or improving? Is it worse at a certain time of the day? Is there ‘sun-downing’?)
- specific examples of the complaint, where possible
- cognitive concerns other than memory, such as in language, executive function or social cognition, and personality changes (see Table 1 for examples of questions)
- functional capacity, including
- basic activities of daily living (ADLs) such as washing, dressing and feeding
- instrumental ADLs such as shopping, managing finances, telephone use, transport use, keeping appointments and managing medications
- particular enquiry into whether a person is still driving and whether they have been involved in any driving accidents or near-misses
- performance on tools such as the Functional Activities Questionnaire, which may be helpful when functional status is unclear from the history4
- substance use history, being sure not to overlook alcohol use
- medication review, as several medication classes can contribute to cognitive impairment, including prescription and over-the-counter medications. In particular, it is worth screening for the use of benzodiazepines, anticholinergics, opiates and antiepileptics
- family history of dementia.
Psychiatric and medical evaluation
Medical and psychiatric histories are necessary to assess for risk factors for cognitive impairment and to clarify the differential diagnosis.5 It is important to ask about:
- symptoms of depression – low mood, tearfulness, lack of pleasure in normally enjoyable activities (anhedonia), loss of appetite, sleep disturbance, feelings of guilt and suicidality
- symptoms of anxiety – feeling worried, tense or ‘on edge’ most of the time, initial insomnia, episodes of panic, flashbacks to or nightmares of previous trauma
- cardiovascular risk factors – a history of cardiovascular or cerebrovascular disease, hypercholesterolaemia, hypertension, diabetes, smoking, obesity or atrial fibrillation (these are associated with an increased risk of cognitive impairment), hypotension or hypoglycaemia (which may cause cognitive impairment)
- sensory impairments, which may negatively affect an individual’s capacity to function independently
- history of severe head injury resulting in a loss of consciousness
- cognitive reserve factors, including years of education, engagement in complex mental activities, social activity and physical exercise, all of which are thought to correlate with a reduced risk of MCI.