[Old and depressed and/or demented? - Pseudodepression vs. pseudodementia].

Many elderly patients suffer from both, depressive symptoms and cognitive deficits. Clinically, it oftentimes appears unclear whether the affective or the cognitive problems are primary or secondary. Modern molecular and imaging markers contribute to a more efficient distinction between depression and incipient dementia due to neurodegenerative, vascular, and other diseases. A careful history and clinical investigations are necessary to identify the underlying diseases, but they do not always offer sufficient therapeutic guidance. If in doubt, the condition should always be considered as potentially reversible and treated emphatically (but with age-appropriate caution).