People are connected to other people – their family, friends and co-workers – in what are called social networks. In its simplest form, a social network is a map made up of nodes representing individuals and the connections or ties between them (see figure at right). Even as late as 2004, social networks and collateral health effects were largely ignored in medical care and clinical trials [1]. However, more recently social networks have been gaining increasing attention in healthcare and medicine [2].

Why the increased attention?

When a patient receives medical interventions, there may be unintended health effects in that patient’s social network, i.e. other people to whom that patient is connected. For example, treating a heart attack may cause the patient’s children to change their dietary habits, improving their health and possibly improving their future medical outlook. Knee replacement surgery may allow a wife to better care for her husband, thus improving his health. Helping someone lose weight may influence that persons friends to also lose weight. Indeed, recent scientific studies, two of which are described below, are finding that social networks are quite relevant to health.

Social network studies and health

The prevelance of obesity in the U.S. is increasing [3]. An analysis of the nature and extent of the person-to-person spread of obesity was published recently with surprising results [4]. Researchers found that an individual’s chances of becoming obese increased by 57% if they had a friend who became obese. However, the type of friendship was an important variable: persons in closer, mutual friendships have more of an effect on each other than persons in other types of friendships. Adult siblings also influenced one another, increasing the chance of obesity by 40%. The risk of becoming obese increased by 37% if an individual’s spouse became obese.

Additionally, the sex of friends and siblings was also important [4]:

… pairs of friends and siblings of the same sex appeared to have more influence on the weight gain of each other than did pairs of friends and siblings of the opposite sex. This finding also provides support for the social nature of any induction of obesity, since it seems likely that people are influenced more by those they resemble than by those they do not. Conversely, spouses, who share much of their physical environment, may not affect each other’s weight gain as much as mutual friends do; in the case of spouses, the opposite-sex effects and friendship effects may counteract each another.

The authors note that while connected individuals may share common exposure elements (e.g. environmental factors, experience of simultaneous events, genes) that cause people to gain or lose weight simultaneously, their observations suggest an important role for a process involving the introduction and person-to-person spread of obesity. The study results suggest that the acceptance of obesity can spread through social networks. The change in the acceptance of obesity may alter behavior and affect a person’s food consumption.

Another recent study examined how a spouse’s illness or death affects the subsequent risk of death of their partner. Perhaps the strongest link in a social network, a spouse’s death was found to increase their partner’s chance of premature death by about 20 percent [5]. In fact, the danger to a partner can be much higher within the first month of a spouse’s hospitalization that marks the beginning of a serious or chronic illness. According to the study authors, rising risk months or years later may reflect a decrease in social support.

Social network ties may indeed have unintended health effects in other people to whom a patient is connected. The effects may be positive or negative. An editorial in the British Journal of Medicine [1] a few years ago suggested that:

Doctors, trialists, patients, or policy makers might see reason to take them [the sum of the direct health outcome in the patient and the collateral health effects in others] into account when choosing treatment or evaluating benefit.

Web 2.0, healthcare and medicine

The first incarnation of the web, which we now call web 1.0, has been summed up as essentially all about commerce, while web 2.0 is almost all about people and participation [6]. Web 2.0 services, including social networking services, blogs, collaborative filtering, social bookmarking, taging, instant messaging and online tools specifically designed for health search will likely change healthcare as we know it today. These same technologies are expected to play an important role in the future of medicine for physicians and scientists as well as patients. Indeed, a recent review of emerging web 2.0 social networking technologies and software [7] suggests that:

… careful thinking, testing and evaluation research are still needed in order to establish ‘best practice models’ for leveraging these emerging technologies to boost our teaching and learning productivity, foster stronger ‘communities of practice’, and support continuing medical education/professional development (CME/CPD) and patient education.

A blog carnival highlighting posts between web 2.0 and medicine, Medicine 2.0, is currently published biweekly. Still a term to be precisely defined, Medicine 2.0 is the science of maintaining and/or restoring human health through the study, diagnosis and treatment of patients utilizing web 2.0 internet-based services, including web-based community sites, blogs, wikis, social bookmarking, folksonomies (tagging) and Really Simple Syndication (RSS), to collaborate, exchange information and share knowledge. Physicians, nurses, medical students and health researchers who consume web media can actively participate in the creation and distribution of content, helping to customize information and technology for their own purposes.

The tenth, jubilee edition of the Medicine 2.0 blog carnival was hosted right here on Highlight HEALTH. There, you’ll find links to many articles that discuss Web 2.0 in health and medicine.

Health 2.0 – social networking services and health

More generally, web 2.0 empowers everyone in healthcare. The Health 2.0 wiki defines Health 2.0 as:

New concept of healthcare wherein all the constituents (patients, physicians, providers, and payers) focus on healthcare value (outcomes/price) and use competition at the medical condition level over the full cycle of care as the catalyst for improving the safety, efficiency, and quality of health care.

In this context, Health 2.0 extends far beyond social networking. However, according to The Health Care Blog,

Our definition [of Health 2.0] is currently focusing on user-generated aspects of Web 2.0 within health care but not directly interacting with the mainstream health care system.

This means things like health search, communities (online social networks) and tools for individual and group consumer use.

What are online social networks? An online social network is a relatively new type of virtual community that is designed to allow members to build relationships with other members of the community. Web 2.0 empowers users, encouraging members to create content online to be shared with other readers. Users can post information on their profile page that is accessible by other members of the community. Additionally, these social networks also typically offer the ability to create additional personal web pages — blogs, image galleries, video clips — that help to build relationships with other members.

According to a survey by Manhattan Research, 9.9 million consumers, in addition to reading weblogs, regularly post health information online and learn from each other [8]. People are clearly using these tools.

Over the coming months, a series of review articles will be published here describing a number health-focused social networks, what they have to offer and how they can affect your health. Stay tuned.

References

1. Christakis NA.
2. Christakis and Fowler. The spread of obesity in a large social network over 32 years. N Engl J Med. 2007 Jul 26;357(4):370-9. Epub 2007 Jul 25.
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3. Christakis and Allison. Mortality after the hospitalization of a spouse. N Engl J Med. 2006 Feb 16;354(7):719-30.
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4. Barsky and Purdon. Introducing Web 2.0: social networking and social bookmarking for health librarians. Journal of Canadian Health Library Association 2006, 27, 7-8.
5. Kamel Boulos and Wheeler. The emerging Web 2.0 social software: an enabling suite of sociable technologies in health and health care education. Health Info Libr J. 2007 Mar;24(1):2-23.
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6. Forecasting the Future: Consumers 2010. Manhattan Research.