History:- Take a careful history from the patient and the relative, concentrate mainly on the onset and progression of symptoms, , take careful drug history, social history. Deterioration of cognitive function is slow in Alzheimer disease within years , faster in vascular dementia, and very rapid in reversible like metabolic causes.
Deterioration occurs in :-
retention of new information like appointments, events, or working a new household appliance)
Managing complex tasks e.g. Paying bills , cooking a meal)
Language ( word finding difficulty)
Behaviour ;- become aggressive, irritability, poor motivation and wandering)
Amnesia – early features are impaired new learning & recall, disorientation in time & place, late features include impaired semantic memory & visuospatial memory
Aphasia (dysphasia) – deficits in cortical language function – early features are nominal aphasia, verbal perseveration, late features include mutism & echolalia
Apraxia (dyspraxia) – common forms are: ideomotor dyspraxia (cannot carry out motor function to command), constructional dyspraxia (manifested by inability to copy intersecting pentagons or draw a clockface)
Cerebrovascular disease: focal signs on neurological testing & evidence of cerebrovascular disease on brain imaging (CT or MRI): multiple large infarcts, single infarct in the angular gyrus, thalamus, basal forebrain or PCA or ACA territories, or multiple basal ganglia & white matter lacunar infarcts or extensive periventricular white matter lesions or a combination of the above
A relationship between the onset of dementia & the presence of cerebrovascular disease:
Onset of dementia within 3 months of a stroke
Abrupt deterioration in cognitive function or a fluctuating or stepwise deterioration
CT large ventricle disproportional to cerebral atrophy
MMSE and gait assessment before LP
LP is diagnostic and therapeutic ( normal pressure, remove 20-30ml and re-assess gait and cognitive function)
Some improve with ventricular-peritoneal shunt. Gait is more likely to improve. Complication infection and SDH
Differential Diagnosis Causes of memory problems / confusion that are not dementia Delirium Depression ‘pseudo-dementia’ Mild cognitive impairment or benign cognitive impairment of aging Learning difficulties Previous brain injury
Memory Complaints in Aging, Depression & Dementia Aging Depression Dementia Complaint May report a mild or subtle memory problem More likely to complain about their memory Expresses variable, non-specific memory problems or may be unaware Functional Interference No interference with daily functioning Minimal interference- functional problems more likely due to mood disorder Clearly interferes with daily functioning: missing appointments, unpaid bills, medication compliance Cognitive Status Onset of problem unclear. Cognition is normal on testing Onset may be reported as sudden, subtle deficits on testing only Gradual onset & progression Cognition impaired on testing Mood Not associated with depression or anxiety Associated with a depressed or anxious mood May be associated with fluctuating or blunted affect
An 82 year old lady presents having had recurrent falls, she doesn’t know why she is in hospital, her niece reports that she was fully able to look after herself and was driving 4 weeks ago. She is covered in bruises and her obs/WCC/urine dipstix/chest X-ray are normal. What is the most likely diagnosis?
You are asked to review a 79year old surgical patient with “confusion” He has been confused since admission and looks thin and unkempt. He does not know where he is but is GCS 15. His son tells you he has stopped being able to cook meals, and does not recognise his grandchildren anymore. This has been going on for over a year. What is the likely diagnosis?
An 86 year old lady is brought in with dehydration, apart from a raised urea her other investigations are normal. She reports having a memory problem which she is very anxious about, on testing her cognitive function is just below normal. She has trouble concentrating on the test. On the ward she is able to wash and dress herself, but keeps to herself. What is the likely diagnosis?
You are called to the ward at night because a patient is threatening the nurses with his Zimmer frame. The nurses report that he is usually a “lovely old man” but today he has been more agitated. He is currently being treated for a UTI. What is the likely diagnosis?