Social lntegration buffers stress in New York police following the 9/11 terrorist attack

Introduction: Being socially integrated is regarded as a protective factor enabling people to cope with adversity. Methods: We examined whether such an effect is found among New York police officers who responded to the 9/11 terrorist attack on the World Trade Center (WTC). The WTC Health Registry is a large longitudinal database on the health of people affected by the attack and its aftermath, including 2,940 police officers completing surveys in 2003-2004 (Wave 1) and 2006-2008 (Wave 2). The research aims at identifying social integration as a beneficial resource factor accounting for less severe stress responses in those more socially involved. A moderated mediation model was specified using event exposure as a distal predictor, earlier stress response as a mediator, and later stress response as an outcome, and social integration as a putative moderator of this mediating relationship. Results: The mediation hypothesis was confirmed, and moderation occurred at two stages. First, there was a multiplicative relationship between exposure levels and social integration: the higher the exposure level, the more stress responses (main effect) occur, but this effect is buffered by a high level of social integration (interaction effect). Second, Wave 1 stress interacted with social integration on Wave 2 stress: the more the police officers were socially integrated at Wave 2, the lower the Wave 2 stress (main effect), in a synergistic manner (interaction effect). Conclusion: This study showed that social integration among NY police officers who responded to the 9/11 terrorist attack was associated with less severe stress responses.