Cognitive function in UK community-dwelling African Caribbean elders: normative data for a test battery

Many 'first generation' African Caribbean residents in the UK have now reached ages where risk of cognitive impairment and dementia starts to increase. In addition, conditions which may impair cognitive function, such as hypertension, diabetes and stroke, have high prevalence rates in African Caribbean populations. However, there is a lack of normative data for cognitive tests in this ethnic group. Cognitive assessment was carried out in a south London community population of 285 African Caribbean participants aged 55-75 years. Tests were drawn principally from the consortium to establish a registry for Alzheimer's disease (CERAD) battery (Boston Naming Test, verbal fluency, word list recall, and Trailmaking Tests A and B) and also included orientation items from the Mini-Mental State Examination (MMSE) and the Clock Drawing Test. Independent effects of age, sex, education and occupation were identified on scores for most but not all cognitive tests. Compared with normative data for African American populations, lower scores on verbal fluency and the Boston Naming Test were observed but scores on memory tests were comparable. Normative data for the tests are presented, stratified by level of education.