Neurocognitive Disorders in Older Adults (Vascular Dementia)

Abstract

Recent developments in the understanding of the relationship between vascular risk factors, vascular cognitive disorders and dementia have led to a renewed interest in these risk factors and their management. The role of the primary care physician in the prevention, control and management of all aspects of vascular diseases is highlighted. Diagnostic criteria in the DSM, ICD and VASCOG systems are examined, in particular their relevance and usefulness in primary care settings. Cognitive domains in a “bedside” testing schedule may be helpful for the primary care physician in their daily practice. Primary and secondary care for people with vascular cognitive disorders places the primary care physician in crucial roles.

Appendix

Suggested “bedside” testing of cognitive domains listed above.

For frontal dysexecutive testing, the Frontal Behavioural Inventory (FBI) provides a useful schedule of 24 items which can be used in primary care setting [31].

1.1 Screening Inventories

Numerous assessments exist, and many brief assessments have been developed which are easy to administer and score. An important aim of using these screening instruments is to pick up cases of dementia as early as possible, since studies have shown that more than 50% of cases of dementia, most especially the mild to moderate ones, are missed by clinicians during routine clinical evaluation. They are simple to administer and require little time to do so.

• Mini-Mental State Examination (MMSE) [31, 32]: Developed in 1975, with several modifications released since, the MMSE is the most widely known and researched screening tool. It is divided into two sections and takes 10–15 min to administer. Research indicates that it has satisfactory reliability and validity. It covers six areas of cognitive functioning: orientation, immediate recall, attention and calculation, language (including following verbal and written instructions and writing a spontaneous sentence) and copying interlocking pentagons. MMSE scores in the moderately impaired range can indicate either cognitive impairment associated with depression or an independent cognitive disorder [33].

• Clock-Drawing Test (CDT): CDT tests memory, adaptive functioning, information processing and visual-spatial and executive functioning. A person is asked to draw a clock face (with or without a pre-drawn circle) and indicate a specified time. The more distorted and inaccurate the drawings are, the more likely the person has dementia [34].

• Time and Change Test: This tests comprehension, working (or task completion) memory and planning and calculating skills. A person is given 60 s and two attempts to read the time on a clock and then is given 3 min and two attempts to make change for a dollar with three quarters, seven dimes and seven nickels [35]. Word recall: A person without memory problems should be able to remember at least three unrelated words and be able to recite them back after interruption with a distracting task. Someone who cannot remember at least two words out of three may have cognitive impairment. Another test is to ask a person to name as many items as possible in a given category, such as fruits or animals. Naming fewer than ten items in 1 min suggests slowed mental functioning [35].

• Mini-Cognitive Assessment Instrument (Mini-Cog): This test has been proven to assess a person’s registration, recall and executive function and be effective culturally and educationally [36].

• General Practitioner Assessment of Cognition (GPCOG): This tool, developed in 2002, is used for screening cognitive impairment in the primary care setting. The GPCOG includes a 4-min patient assessment and a 2-min caregiver interview. A web-based tool is available. Research has shown it to perform at least as well as the MMSE [37].

Note: Most of these instruments are standardized screening tools for dementia in accordance with internationally recognized guidelines. It should however be noted that clinicians and researchers in multi-ethnic and diverse cultural societies in Asia and Africa have customized few of these screening tools to the culture, language and literacy level of their local populations, such as “Test of Senegal,” developed for sub-Saharan African population. Other examples of such customized screening inventories are from the Indianapolis-Ibadan Dementia Project (IIDP) domiciled in Ibadan, Nigeria, that is, “Clinical Home-based Interview to assess Function” (CHIF), which measures activities of daily life drawing out statements from existing standard questionnaires, and “stick design”, a questionnaire that measures visuo-constructional abilities. For indigenous Australians, the Kimberley Indigenous Cognitive Assessment (KICA) tool [38] has been well validated for this population.