Dementia case study with questions and answers
Common dementia exam questions for medical finals, OSCEs and MRCP PACES
The case below illustrates the key features in the assessment of a patient with dementia or undiagnosed memory decline. It works through history, examination and investigations – click on the plus symbols to see the answers to each question
Part 1: Mavis
- Mavis is an 84-year old lady, referred to you in the memory clinic for assessment of memory impairment. She attends in the company of her son and daughter-in-law.
- On the pre-clinic questionnaire her son has reported a severe deterioration in all aspects of her cognition over the past 12 months.
- The patient herself acknowledges that there have been memory problems, but feels it is just her short term memory that is an issue.
What are the key features to address in a dementia history?
- To begin the history, start broadly. Build rapport and establish both the patient’s view on memory impairment (if any) and the family’s (or other collateral history).
- Try to establish:
- Patient’s (and collateral) view of memory decline
- Biographical history
- Objective view of memory decline (e.g. knowledge of current affairs)
- Impact of memory decline on day-to-day living and hobbies
- Social history, including safety and driving
- General medical history (especially medications)
- See below for details on these…
What specific features of memory decline do you want know?
- Determine the nature of memory loss.
- Is it for everything or are specific details missed out/glossed over?
- Try to pin down specific details (e.g. names of people/places).
- At what time in chronological order do things start to get hazy?
What are the key parts of a biographical history?
- Length of time in education
- If under 12 years this will lead to additional point being awarded on some cognitive tests
- General biography
- Ask about long term memories, e.g. wedding day or different jobs
- Then move on to more recent memories, e.g. last holiday
What are the best way to get a current overview of memory?
- Knowledge of current affairs is commonly used
- If your patient watches the news/read newspapers on a regular basis, ask them to recount the headlines from the past few days.
- Be sure to look for specifics to prevent your patient masking memory deficiencies with broad statements. For example: “The government are incompetent, aren’t they?!” should be clarified by pinning down exactly why they are incompetent, for example: “Jeremy Hunt”.
- Memory loss around interests can also be used
- If they like to read, can they recall plotlines from current books or items from magazines?
- If they watch TV, can they recount recent plot lines from soaps, or formats of quiz shows?
How do you measure the impact of memory loss on daily life?
- Ask about hobbies and other daily activities, and whether or not these have declined recently.
- If your patient no longer participates in a particular hobby, find out why: is it as a result of a physical impairment (e.g. arthritis making cooking difficult), or as the result of a loss of interest/ability to complete tasks (e.g. no longer able to complete crosswords/puzzles).
- Once you have a good idea of the memory decline itself, begin to ask about other features. Including a social and general medical history.
What are the key features of a social history in memory decline?
- Review their social history and current set-up, and also subjective assessments from both patient and family over whether or not the current arrangements are safe and sustainable as they are.
- Particulars to establish are:
- Previous and ongoing alcohol intake
- Smoking history
- Still driving (and if so, how safe that is considered to be from collateral history)
- Who else is at home
- Any package of care
- Upstairs/downstairs living
- Meal arrangements (and whether weight is being sustained).
- Of all these issues, that of driving is perhaps one of the most important, as any ultimate diagnosis of dementia must be informed (by law) to both the DVLA and also the patient’s insurers. If you feel they are still safe to drive despite the diagnosis, you may be asked to provide a report to the DVLA to support this viewpoint.
Now perform a more generalised history, to include past medical history and – more importantly – a drug history.
What particular medications should you look out for?
- Look out in particular for any medications that can cause confusion, and in particular those that may be making an underlying dementia more pronounced. In particular:
- Oxybutynin, commonly used in primary care for overactive bladder (anticholinergic side effects)
- Also see how the medications are given (e.g. Dossett box)
- Are lots of full packets found around the house?
Part 2: The History
On taking a history you have found:
- Mavis was able to give a moderately detailed biographical history, but struggled with details extending as far back as the location of her wedding, and also her main jobs throughout her life.
- After prompting from her family, she was able to supply more information, but it was not always entirely accurate.
- Her main hobby was knitting, and it was noted that she had been able to successfully knit a bobble hat for her great-grand child as recently as last month, although it had taken her considerably longer to complete than it might have done a few years previously, and it was a comparatively basic design compared to what she has been able to create previously.
- She has a few children living in the area, who would frequently pop in with shopping, but there had been times when they arrived to find that she was packed and in her coat, stating that she was “just getting ready to go home again”.
- She had been helping occasionally with the school run, but then a couple of weekends ago she had called up one of her sons – just before she was due to drive over for Sunday lunch – and said that she could not remember how to drive to his house.
- Ever since then, they had confiscated her keys to make sure she couldn’t drive. Although she liked to read the paper every day, she could not recall any recent major news events. Before proceeding to examine her, you note that the GP referral letter has stated that her dementia screen investigations have been completed.
What basic investigations form a dementia screen?
- Full blood count
- Raised WCC suggests infection as a cause of acute confusion
- Uraemia and other electrolyte disturbances can cause a persistent confusion.
- Again, to help rule out acute infection/inflammatory conditions
- Liver failure can cause hyperammonaemia, which can cause a persistent confusion.
- Hyper- or hypothyroidism can cause confusion.
- B12 deficiency is an easily missed and reversible cause of dementia.
- CT Head
- This looks for space occupying lesions/hydrocephalus which may cause confusion.
- This can also help to determine the degree of any vascular component of an ultimately diagnosed dementia.
Part 3: Examination
- With the exception of age-related involutional changes on the CT head (noted to have minimal white matter changes/small vessel disease), all the dementia screen bloods are reassuring.
- You next decide to perform a physical examination of Mavis.
What are the key points in the examination of a patient with memory difficulty?
- Important physical findings that are of particular relevance to dementia, are looking for other diseases that may have an effect on cognition.
- Neurological examination
- To look for evidence of stroke – unlikely in this case given the CT head
- Examine for Parkinsonism
- Gait (shuffling) and limb movements (tremor, rigidity, bradykinesia)
- Affect is also important here and may also point to underlying depression
- Cranial nerves
- Pay attention to vertical gaze palsy, as in the context of Parkinsonism this may represent a Parkinson plus condition (e.g. progressive supranuclear palsy).
- It is also useful to look at observations including blood pressure (may be overmedicated and at risk of falls from syncope) and postural blood pressure (again, may indicate overmedication but is also associated with Parkinson plus syndromes e.g. MSA)
Part 4: Cognitive Testing
- On examination she is alert and well, mobilising independently around the clinic waiting room area. A neurological examination was normal throughout, and there were no other major pathologies found on a general examination.
- You now proceed to cognitive testing:
What cognitive testing modalities might be appropriate?
Part 5: Diagnosis
- Mavis scores 14/30 on a MOCA, losing marks throughout multiple domains of cognition.
What is, clinically, the most likely diagnosis?
- Given the progressive nature of symptoms described by the family, the impairment over multiple domains on cognitive testing, and the impact on daily living that this is starting to have (e.g. packing and getting ready to leave her own home, mistakenly believing she is somewhere else), coupled with the results from her dementia screen, this is most likely an Alzheimer’s type dementia.
How would you manage this condition?
- You should proceed by establishing whether or not Mavis would like to be given a formal diagnosis, and if so, explain the above.
- Medical therapy: acetylcholinesterase inhibitors
- You should review her lying and standing BP and ECG, and – if these give no contraindications – suggest a trial of treatment with an acetylcholinesterase inhibitor, such as donepezil.
- It is important to note the potential side effects – the most distressing of which are related to issues of incontinence.
- If available, put her in touch with support groups
- Given the history of forgetting routes before even getting into the care, advise the patient that she should stop driving and that they need to inform the DVLA of this (for now, we will skip over the depravation of liberty issues that the premature confiscation of keys performed by the family has caused…)
- Inform others
- The GP should be informed of the new diagnosis, and if there are concerns over safety, review by social services for potential support should be arranged.
- Follow-up is advisable over the next few months to see whether the trial of treatment has been beneficial, and whether side effects have been well-tolerated.
Now click here to learn more about dementia
Perfect revision for medical students, finals, OSCEs and MRCP PACES
…or click here to learn about the diagnosis and management of delirium