Many older people have the early stages of a future dementia in the form of mild cognitive impairment.
Unless specifically looked for, many older people may simply ignore the first signs of memory loss as eccentricity in older age. The age at which cognitive dysfunction becomes a more noticeable issue will depend on cognitive reserve, type of occupation, other underlying conditions (in particular heart disease, diabetes, and hypertension).
The usual first step is a tailored history, with some simple bedside assessment using paper and pencil assessments such as a mini-mental state examination (MMSE). The results will guide further inquiry.
It is important to remember that depression, at any age, may manifest as a cognitive disorder, which is reversible, and termed ‘pseudodementia’.
Vitamin deficiencies and endocrine disorders may also present with both signs of depression and symptoms of dementia e.g. hypothyroidism.