The article by Adelman and colleagues ^{Reference Adelman, Blanchard, Rait, Leavey and Livingston1} made an important contribution in exploring dementia in older people of African–Caribbean origin in the UK. This article paves a way for policy makers in assessing the public health implications of this ubiquitous condition in terms of care burden and economic impact. However, this research study raises important issues.

Previous studies ^{Reference Adelman, Blanchard and Livingston2} consistently indicate increased prevalence of dementia in older African–Caribbean people when compared with the indigenous White population in the UK. The magnitude of this difference between these populations is not clear. Hence, there is a definite need for well-planned epidemiological studies to determine the actual burden of disease. Surprisingly, Adelman et al’s study ^{Reference Adelman, Blanchard, Rait, Leavey and Livingston1} presumed that vascular factors such as hypertension and type 2 diabetes are likely to increase the burden of dementia in the African–Caribbean population. However, the possibility of other risk factors such as depression, illiteracy and prevalence of apolipoprotein 4, which, presumably, increase the chances of subsequent dementia, needs more emphasis. ^{Reference Stewart, Russ, Richards, Brayne, Lovestone and Mann3,Reference Kalaria, Maestre, Arizaga, Friedland, Galasko and Hall4} Current data from sub-Saharan Africa and India ^{Reference Kalaria, Maestre, Arizaga, Friedland, Galasko and Hall4} suggest that age-adjusted dementia prevalence estimates in 65-year-olds are low (1–3%) compared with other low- and middle-income countries. It appears that there is a need to identify potentially modifiable environmental/genetic factors to explain the increased prevalence of dementia when this population migrated to the UK. Therefore, future studies are needed to identify these risk factors in this migrant population.