Objectives: We examined whether social networks had a protective association with incidence of dementia among elderly women.
Methods: We prospectively studied 2249 members of a health maintenance organization who were 78 years or older, were classified as free of dementia in 2001, and had completed at least 1 follow-up interview in 2002 through 2005. We used the Telephone Interview for Cognitive Status-modified, the Telephone Dementia Questionnaire, and medical record review to assess cognitive status. We used the Lubben Social Network Scale-6 to assess social network. We estimated hazard ratios for incident dementia with Cox proportional hazards models, adjusting for age at entry, education, hormone use, cognitive status scores, and health conditions.
Results: We identified 268 incident cases of dementia during follow-up. Compared with women with smaller social networks, the adjusted hazard ratio for incident dementia in women with larger social networks was 0.74 (95% confidence interval=0.57, 0.97).
Conclusions: Our findings suggest that larger social networks have a protective influence on cognitive function among elderly women. Future studies should explore which aspects of social networks are associated with dementia risk and maintenance of cognitive health.