BRIEF REPORTS Being Popular Can Be Healthy or Unhealthy: Stress, Social Network Diversity, and Incidence of Upper Respiratory Infection

Diverse social contacts are generally associated with better health. However, diverse contacts can increase exposure to infectious agents. This should increase risk for disease, particularly among those whose host resistance is otherwise compromised (e.g., stressed individuals). In this prospective study, healthy college students who completed questionnaires assessing social network diversity and stressful life events were subsequently interviewed weekly for 12 weeks to track incidence of upper respiratory infections (URIs). URI episodes were defined by a symptom criterion and by clinically verified self-reported illness. Stress and diversity of social contacts interacted; diversity was associated with more illnesses among those with more stressful life events and slightly fewer illnesses among those with fewer stressful life events. Associations remained after controlling for neuroticism. The hypothesis that multiple ties to friends, family, work, and community are beneficial in terms of physical health has gained substantial support recently. Particularly provocative is epidemiologic evidence that those who have more diversified social networks—that is, people who are married; people who interact with family members, friends, neighbors, and fellow workers; and people who belong to social and religious groups—live longer (House, Landis, & Umberson, 1988), are more likely to survive myocardial infarction (Berkman, 1995), and are less likely to suffer a recurrence of cancer (Helgeson, Cohen, & Fritz, 1998) than their counterparts with fewer types of social relationships. A study of host resistance to upper respiratory infections (URIs) found that persons with more diverse networks were less likely to develop a cold when they were experimentally exposed to a cold-causing virus (Cohen, Doyle, Skoner, Rabin, & Gwaltney, 1997). Even so, having a diverse social network may not always be a good thing. For example, it is likely that diverse social networks are associated with face-to-face contact with a broad range of people and hence an increased risk of exposure to a range of infectious agents. Several studies provide support for increased numbers of URIs with increased exposure to others. Dingle, Badger, and Jordan (1964) found that individuals from larger families averaged more physician-verified colds per year than people from smaller families. Graham, Woodward, Ryan, and Douglas (1990) found that children prone to respiratory illness were more likely to attend day care, have siblings less than 14 years of age, and have mothers who regularly attended social or religious meetings. In a prospective study, Clover, Abell, Becker, Crawford, and Ramsey (1989) found that individuals from families reporting high levels of cohesion (emotional bonding) were more likely than their less-enmeshed counterparts to experience an incidence of laboratory-documented influenza B infection. The authors suggested that families reporting low cohesion levels may have touched less, kissed less, and shared eating and drinking utensils less, thus minimizing their viral exposure. It is likely that the exposure effects of social contact occur primarily among vulnerable members of the population—those whose host resistance to infectious agents is otherwise compromised. Because psychological stress is associated with compromised host resistance to viral infectious illness (e.g., Cohen, Tyrrell, & Smith, 1991; Stone et al., 1992), those with elevated stress levels should be particularly susceptible to the increased risk of exposure associated with social diversity. Although there have