Subjective memory complaints (SMC)

Subjective memory complaints without objective cognitive impairments are common in elderly people. Recent evidence indicates subjective memory complaints is not merely a sign of a depressive state or an aging phenomenon, but an important risk factor for proceeding to mild cognitive impairment (MCI) and dementia in the future. Even when cognitively intact through the life, people with SMC tend to have more Alzheimer's disease (AD) pathology in the brain, which recently been defined as preclinical AD. Though not having the same clinical significance compared to MCI, we should keep in mind that elderly people with SMC are at risk for future cognitive decline and try to find out what specific biological backgrounds or clinical characters increase this cognitive risk.