Transcultural expression of subcortical vascular disease

Background: Many transcultural issues pertaining to subcortical vascular disease remain unanswered, and there is a relative paucity of research on stroke and dementia in non-Western societies. Objective: To describe variations in the epidemiology of stroke and dementia, the recognition of dementia as an entity across cultures, the cultural specificity of screening tools and assessment instruments, and cultural influences on the management of stroke and dementia. Results: Several studies have pointed out differences in the subtypes and outcomes from stroke across different world regions. Notably, non-Western populations may have a higher rate of hemorrhage, whilst in ischemic stroke subcortical vascular disease is predominant. A low prevalence of dementia has been demonstrated in many studies of non-Western populations. Factors proposed to account for this include protective family attitudes, a lower frequency of ApoE4 and the high mortality of non-Western dementia subjects, which may mask a high age-specific incidence rate. Other medical factors such as training, diagnostic skills, the availability of investigations and healthcare provision may also play a role, as would patient specific cultural attitudes towards ageing and mental health, together with differences in language, social customs and literacy. It has been suggested that there is a major difference between Western and Asian nations in the ratio of vascular dementia to Alzheimer disease. However, few epidemiological field studies have utilized neuroimaging and the reported rates for particular diagnoses should be interpreted cautiously. A recent population study in Japan, which utilized screening by neuropsychologists and CT scanning, showed that vascular dementia accounted for nearly half the cases of dementia. Subcortical vascular disease accounts for the majority of patients with vascular dementia (VaD). Conclusions: With the rapid demographic changes taking place in non-Western countries, non-communicable diseases such as dementia and stroke will increasingly come to dominate disease burden. More studies are required to prevent and treat these diseases. (C) 2004 Elsevier B.V. All rights reserved.