Social media in communicating health information: an analysis of Facebook groups related to hypertension.

INTRODUCTION: We studied Facebook groups related to hypertension to characterize their objectives, subject matter, member sizes, geographical boundaries, level of activity, and user-generated content.

METHODS: We performed a systematic search among open Facebook groups using the keywords "hypertension," "high blood pressure," "raised blood pressure," and "blood pressure." We extracted relevant data from each group's content and developed a coding and categorizing scheme for the whole data set. Stepwise logistic regression was used to explore factors independently associated with each group's level of activity.

RESULTS: We found 187 hypertension-related Facebook groups containing 8,966 members. The main objective of most (59.9%) Facebook groups was to create hypertension awareness, and 11.2% were created primarily to support patients and caregivers. Among the top-displayed, most recent posts (n = 164), 21.3% were focused on product or service promotion, whereas one-fifth of posts were related to hypertension-awareness information. Each Facebook group's level of activity was independently associated with group size (adjusted odds ratio [AOR], 1.02; 95% confidence interval [CI], 1.01-1.03), presence of "likes" on the most recent wall post (AOR, 3.55, 95% CI, 1.41-8.92), and presence of attached files on the group wall (AOR, 5.01, 95% CI, 1.25-20.1).

CONCLUSION: The primary objective of most of the hypertension-related Facebook groups observed in this study was awareness creation. Compared with the whole Facebook community, the total number of hypertension-related Facebook groups and their users was small and the groups were less active.