Knowing your partner is not enough: spousal importance moderates the link between attitude familiarity and ambulatory blood pressure.

Close relationships have been linked to cardiovascular morbidity and mortality. More research is needed, however, on the social and biological processes responsible for such links. In this study, we examined the role of relationship-based attitudinal processes (i.e., attitude familiarity and partner importance) on ambulatory blood pressure during daily life. Forty-seven married couples completed a questionnaire regarding their own attitudes, perceptions of their partner's attitudes, and perceptions of partner importance. They also underwent a 1-day ambulatory assessments of daily spousal interactions and blood pressure. Partner importance was related to better interpersonal functioning (e.g., partner responsiveness) and lower ambulatory systolic blood pressure. More interestingly, partner importance moderated the links between attitude familiarity and both ambulatory systolic and diastolic blood pressure. This statistical interaction revealed that simply knowing a partner's attitudes was not enough as partner knowledge was primarily related to lower ambulatory blood pressure when they were also viewed as more important. These data are discussed in light of how attitude familiarity and spousal importance may jointly influence health outcomes and the social-cognitive mechanisms potentially responsible for such links.