The Role of Marriage and Partnership in Caregiving: Links to the Hypothalamic-Pituitary-Adrenal Axis.

Family caregiving is a major stressor that can compromise health and activate the HPA axis-one of the body's primary physiological stress systems. A multitude of past research shows that marital status and characteristics of the partnership can help buffer caregiving burden and enhance coping resources to mitigate negative physiological outcomes. However, there are numerous ways to measure the role of the spouse, and the conceptualization of these measures may have different implications for the links between stress and health. Moreover, many studies are limited by designs that specifically recruit both partners into a study, resulting in samples that may be skewed towards couples that already have higher relational quality or provide more support. In this study, parent caregivers of children (n=170) with rare genetic conditions and parent caregivers of typically developing children chose to participate alone or jointly as a couple. Information on caregiving burden, use of individual coping strategies, marital status, and caregiving-specific support by spouse/partner was collected via surveys. Blood samples were collected to assess serum arginine vasopression (AVP) levels-one biomarker of the HPA axis. Caregiving burden was positively associated with AVP, while greater use of individual coping resources was negatively associated with AVP. Marital status was directly linked to lower AVP, while caregiving-specific support and joint participation moderated some of the associations between caregiving burden, individual coping, and AVP. These findings highlight the need to consider multiple aspects of marriage and partnership as potential influences on the biological response to stress in parent caregivers.