A literature review and meta-analysis of 23 international studies on the under-detection (i.e. the failure to achieve a diagnosis) of dementia identified a pooled rate of undetected dementia assessed to be 61.7%. The rate of under-detection was higher in China and India compared with that in Europe and North America.
The rate of under-detection was higher in community-based settings too, and in populations containing a higher proportion of men. The under-detection of dementia may also be associated with low income / socio-economic status, with younger age, and the involvement in diagnosis from general practitioners. Under-diagnosis appears to be lower in studies involving use of Mini-Mental State Examination (MMSE) diagnosis criteria.
Wide variations in the detection of dementia are thought to result in undesirable health inequalities. Although there are no recommendations for the screening of older adults for dementia in many countries currently (including the UK), the authors of this review suggest that earlier diagnosis / better rates of diagnosis should be a priority to reduce diagnostic inequality and to improve post-diagnostic care in the community. This may perhaps be particularly important for high-risk groups. including groups with low socio-economic status, non-local language speakers and people living alone.
Lang, L. Clifford, A. [and] Wei, L. [et al] (2017). Prevalence and determinants of undetected dementia in the community: a systematic literature review and a meta-analysis. BMJ Open. February 3rd 2017; 7(2): e011146.