Mild cognitive impairment: advantages of a comprehensive neuropsychological assessment

Mild cognitive impairment (MCI) could be an auspicious candidate for an early marker of a beginning dementia. However, although MCI is accepted as a heterogeneous condition by now, performance testing or diagnosis is often based on a limited number of cognitive tests. Furthermore, there is still disagreement about the necessity to include subjective cognitive complaints as a diagnostic criterion. The current study intends to examine the character of MCI when diagnosis is based upon multiple cognitive domains and does not require the presence of subjective complaints. 130 subjects from the HelMA (Helmholtz Alliance for Mental Health in an Ageing Society) longitudinal study completed a comprehensive neuropsychological test-battery and were diagnosed as either normally-ageing controls or patients with MCI. The prevalence rate of MCI was as high as 46.2%, hereby exceeding most estimates of other studies. Patients with MCI performed worse than controls in each of the 29 administered tests with memory being the predominant impaired cognitive domain. Surprisingly, there was no single patient with a purely non-amnestic impairment, considerably contradicting hitherto existing studies. The rather different distribution of impairment and prevalence rate emphasizes the demand of testbatteries including all cognitive domains so that inferences about MCI are as all-encompassing as possible.