An Educational Case-Report Of A Person With Vascular Dementia And Comparison With The Characteristics Of Other Dementias

Case Presentation

Mrs M.O, a 60 year old retired nurse was referred to the Old Age Psychiatry Out-patient Unit by the endocrinologists on account of difficulty with behaviours such as undue irritability, anger outburst and hostility. She was first seen 6 years earlier and managed for type 2 diabetes mellitus, hyperlipidaemia, and systemic hypertension using relevant medications as prescribed by the endocrinologist physicians. About 2 years before the referral, she had complaints of sudden onset generalized slowness, occasional forgetfulness and unexplained weakness. The symptoms affected her ability to perform her usual chores like cooking and cleaning. In the year before her presentation to the outpatient unit, her forgetfulness was noticed to have become increasingly worse. She regularly forgot where she kept personal belongings such as her wallet and mobile phone. Repeatedly, she had to be reminded of the details of recent conversations. In addition, she was reported to have lost the ability to use money correctly over the period of her illness. As a result of this, she was stopped by her family members from shopping on her own. Eventually, she started having progressive difficulties with bathing and dressing which caused much distress to the family, especially her husband who was the principal caregiver.

Assessments

The mental state examination of Mrs. M.O at presentation to the unit revealed a middle aged woman with poor attention and concentration, poor registration and immediate recall with poor short and long term memory. Her blood pressure was 130/70mmHg. The only obvious neurological examination finding was abnormal ankle jerk reflex on the left side. The results of laboratory tests for fasting glucose, fasting lipids, thyroid function tests and other relevant investigations were also within normal limits. A selection of tests from the modified version of the Consortium to establish a registry for Alzheimer ’s dis ease (CERAD) neuropsychological  battery was  administered on Mrs. M.O.  The local normative references  for  this battery had been established for the Nigerian elderly [5]. The tests revealed impairment in multiple cognitive domains. Notably, she had a score of 16 out of a minimum of 22 expected for her level of education on the mini-mental state examination (MMSE). She was able to list 6 words out of 11, after a learning phase. Furthermore, she was able to name 5 animals out of a minimum of 7. A cranial Computerized Tomography (CT) Scan showed evidence of peri-ventricular intensities that were in keeping with white matter changes. Also recorded on the CT scan were multi-focal chronic infarcts and bilateral temporal lobe atrophy.

Clinical diagnosis and treatment

On account of the overall picture, a clinical assessment of vascular dementia was made according to criteria in the fourth revision of the diagnostic and statistical manual of mental disorders (DSM IV) [6]. This was based on the following characteristics: 1), the overall profile of deteriorating cognitive impairment leading to loss in functional ability such as being unable to perform household chores, shopping, bathing and dressing without assistance; 2), the presence of vascular risk fact ors including type 2 diabetes mellitus, hyperlipidaemia, and systemic hypertension, preceding the onset of cognitive impairment; and 3), the occurrence of multiple infarcts visualized on neuro- imaging examination.

She was placed on Tabs Risperidone 0.5mg nightly because of her behavioural symptoms. In addition she was encouraged to continue with her antihypertensives, oral hypoglycaemic agents and statins which are expected to provide ongoing control over the underlying vascular risks. She was planned for follow-up review after two weeks. However, she did not return to the clinic until after 2 months. On the return visit, the husband reported some improvements, evidenced by less hostility. She stopped coming to clinic after the second consultation.

Discussion

Cognitive symptoms

The patient in this case report had cognitive impairments in three broad areas: memory, attention, and executive functions. Global cognit ive impairment was psychometrically evident in her poor performance on the MMSE [5]. Specific impairment in memory was evident in her difficulties with remembering recent conversations, including the location of her personal belongings. Memory impairment was also evident in the problems she had with registration, recall, short and long term memory on the mental state examination. Psychometrically, specific problems with memory were

demonstrated by the poor performance in the word list learning test. In interpreting these changes in memory functions, it is often important to note that they may sometimes result from impairment in attention.

Impaired executive functioning may be responsible for her loss of the ability to use money correctly. This is also a reflection of impaired instrumental activities of daily living (ADL). In other perspectives, the ability to understand the correct value of money may be viewed in terms of an intact calculation ability, an aptitude that may require multiple areas of cognition such as language, memory, visuospatial abilities and executive functions [7]. Abnormality in executive functions was formally demonstrated by the poor performance in the Animal naming test. The patient in the report also had additional problems with dressing, a common problem of praxis that may also reflect impairment in self-care or basic ADL.

While most patients with vascular dementia may show variable or mild impairments in memory, these patients may exhibit more disturbances in attention and executive functions [8]. In contrast, impairment in memory functions may be a common and early presentation in Alzheimer’s disease [9]. Some patients with frontotemporal dementia, especially the behavioural variant may also show impairment in attention and executive functions that may overlap with those of vascular dementia [10]., while agnosia and severe visuo- constructional abnormalities may be more characteristic of Lewy body dementia [11].

Non-cognitive symptoms

The patient in the case report also had non-cognitive symptoms, which started with unexplained slowness and weakness, and later, irritability, anger outburst and hostility. These symptoms are referred to as the Behavioural and Psychological symptoms of dementia (BPSD). In terms of structure, the non-cognitive symptoms in the case reported may be viewed as the ‘affective syndromes’ of dementia [12]. They have also been categorised as ‘mood’ syndromes of dementia in other perspectives [13]. Yet, they have been referred to as ‘depression syndromes’ of dementia [14], or major depression [6] in other classifications. This symptom complex may be non-specific in terms of their diagnostic value in the dementias. However, as in the case report, they may be more commonly seen in the earlier or middle courses of vascular dementia [4]. Similarly, earlier presentations of ‘affective syndromes’ has been repor ted in Alzheimer ’s disea se [15 ]. Per haps, overlapping sub-cortical pathologies between, for example, depression and the sub-cortical dementias,