Dyadic Disruption Theory.

Aspects of couples' romantic relationships are some of the most powerful psychosocial forces shaping mental and physical health, but even high-quality relationships are not universally beneficial for patients. Dyadic health theories have largely focused on chronic illness management that occurs after the couple understands the disease and prognosis, rather than focusing on couples' interdependence in the days and weeks following a sudden and disruptive medical event (e.g., an acute coronary syndrome [ACS] or a stroke). To address this gap, I propose Dyadic Disruption Theory to guide research on couples' reactions to acute medical events and their consequences for individual and dyadic mental health, physical health, and behavior. I propose that dyadic processes of social support, shared reality, and co-rumination can precipitate harmful patient and partner dynamics when couples are distressed early post-event and offer three propositions that inform testable hypotheses. Finally, I discuss implications for early dyadic intervention and future directions for research.