Homophily and health behavior in social networks of older adults

As the majority of adults in the U.S. age, there is an increasing need for better understanding how social relationships impact health. Several studies have shown that social networks have an influence on one's health behaviors. According to Christakis and Fowler, a common network phenomenon, homophily, involves developing relationships with others that are similar to you. The intent of this study is to determine if older adults' health behaviors are shared within social networks. Interviews are underway with 150 older adults, 50 years of age and older, recruited from low-income, county-sponsored senior housing. Participants reported demographic status, personal health behaviors, social network structure, and key health behaviors for themselves and for named alters from within primary and secondary networks. Health behaviors included physical activity, body mass index, and smoking status. To elicit network alters, respondents placed up to four friends or contacts within bull's eye circles and then reported health behaviors for each named contact. Findings from the first 30 participants suggest strong effects for homophily, especially for body mass index. In respondents who were overweight or obese, 56% of contacts were reported to be overweight. In respondents not overweight or obese, only 7% were overweight. These results suggest that health behaviors are shared within older adults' social networks. Public health interventions for older adults should consider the influence that social relationships have on personal health behaviors. Network-based interventions may be required.