Features of daily social interactions that discriminate between older adults with and without mild cognitive impairment.

Objectives: Detecting subtle behavioral changes in everyday life as early signs of cognitive decline and impairment is important for effective early intervention against Alzheimer's disease. This study examined whether features of daily social interactions captured by ecological momentary assessments could serve as more sensitive behavioral markers to distinguish older adults with mild cognitive impairment (MCI) from those without MCI, as compared to conventional global measures of social relationships.

Method: Participants were 311 community dwelling older adults (aged 70 to 90 years) who reported their social interactions and socializing activities five times daily for 14 consecutive days using smartphones.

Results: Compared to those with normal cognitive function, older adults classified as MCI reported less frequent total and positive social interactions and less frequent in-person socializing activities on a daily basis. Older adults with and without MCI, however, did not show differences in most features of social relationships assessed by conventional global measures.

Discussion: These results suggest that certain features of daily social interactions (quality and quantity) could serve as sensitive and ecologically valid behavioral markers to facilitate the detection of MCI.