Social network types and cognitive decline among older Korean adults: A longitudinal population-based study

Social network (SN) has been known to impact on cognitive function in late life. However, knowledge regarding the link between SN of various types and cognitive decline (CD) is limited. This study's aim was to investigate which types of SN are associated with reduced risk of CD 2 years later among community-dwelling older adults.

Secondary analysis of data from 1960 cognitively intact adults 65 years of age or older who participated in the Korean Longitudinal Study of Aging (KLoSA) was employed. K-means cluster analysis was conducted to derive SN types using seven common SN characteristics (marital status, living with children, number of children, frequency of contact with children, frequency of contact with friends, frequency of participation in religious activities, and frequency of participation in social groups). Multivariable linear regression analysis regarding the effects of SN type on CD between 2012 and 2014 was conducted, controlling for covariates.

K-means cluster analyses identified a model with five types of SN as being most optimal, and they were named diverse/couple, diverse/family, congregant, restricted/married, and widowed. The average CD 2 years later was most pronounced in those in the widowed network. Compared with the widowed, older adults in the diverse/couple network and the congregant network at baseline had a lower risk of CD 2 years after initial assessment.

Findings show that older Korean adults embedded in widowed network types are at risk for CD and suggest the importance of having a spouse and religious group activities in maintaining cognitive function in later life.