Age-related cognitive decline and vision impairment affecting the detection of dementia syndrome in old age

Abstract

BackgroundCurrently the Mini Mental State Examination (MMSE) is widely used as a screening instrument for dementia syndrome. Diagnostic validity may be lowered in old age by normal age-related cognitive decline. Furthermore, visual impairment, occurring frequently in old age, leads to missing values which prevent an interpretation of the test result.MethodIn the Berlin Ageing Study (n=516, age range 70–103 years) MMSE and clinical dementia diagnosis, made by a psychiatrist investigating all subjects by the Geriatric Mental State–A and History and Aetiology Schedule interviews, were investigated independently. The MMblind was analysed, an MMSE version for vision impairment in which all items requiring image processing are omitted. The study sample is population-based; dementia cases (DSM–III–R) were excluded on the basis of the clinical diagnosis.ResultsNorms are reported for very old age regarding MMSE as well as MMblind. There is a considerable age effect on MMSE scores. In contrast to MMSE, sensitivity and specificity of the shorter MMblind version are not reduced.ConclusionsThe considerable age effect requires the adaptation of cut-off values for old age. The blind version of the MMSE seems to be a valid instrument improving the applicability of the MMSE in old age.