Effect of social network on body mass index among the elderly

Abstract

Objective: It is known that obesity appears to spread through social ties. The association between other variables related to social network and obesity are unclear. This study aimed to identify communication density or frequency correlated with body mass index (BMI, kg/m2) among the elderly.Methods: This cross-sectional study analyzed data from 660 Koreans (275 men, 385 women) aged 60 years or older, who participated in Korean Social Life, Health and Aging Project (KSHAP) in 2011-2. Communication density is the number of connections in the network reported as a fraction of the total links possible, and communication frequency is average frequency (days per year) of communication between network members. The association between communication density or frequency and BMI was investigated by multiple linear regression analysis.Results: BMI decreased according to tertiles of communication density or frequency both men and women. After adjusted for potential confounders, in men, lower tertile of communication density was associated with higher BMI (regression coefficient ß=1.049, p=0.041), but communication frequency was not significantly associated. By contrast, in women, communication density was not significantly associated, but lower tertile of communication frequency was associated with higher BMI (ß=0.896, p=0.043). Conclusions: Our study suggests that there may be the effect of social network on BMI among the elderly. There might be a gender difference in the relationship between communication density or frequency and obesity.