Spousal bereavement after dementia caregiving: A turning point for immune health.

Losing a spouse can increase the risk for premature mortality, and declines in immune health are thought to play a role. Most of the supporting data have come from cross-sectional studies comparing already-bereaved individuals to matched controls, which provides valuable information about health disparities between groups but does not reveal health changes over time. Moreover, the health consequences of bereavement may be unique for dementia family caregivers, a large and growing segment of the population. The current study sought to evaluate the course of health around 52 dementia spousal caregivers' bereavement by capturing lymphocyte proliferation to Con A and PHA and self-rated health before and after spousal loss. To investigate the moderating role of the social environment, we examined associations between social ties and health trajectories before and after spousal loss. Using piecewise linear mixed models to allow for turning points in caregivers' trajectories, we found that, for the average caregiver, lymphocyte proliferation to both mitogens weakened as bereavement neared and continued to decline after the loss, but at a slower pace. In tandem, perceived health degraded as bereavement approached but rebounded thereafter. Further, we found that socially isolated caregivers showed marked declines in immune responses to Con A and PHA over time both before and after bereavement, whereas their socially connected counterparts had shallower declines to PHA and maintained a level immune response to Con A. In addition, socially isolated caregivers reported poorer health before and after bereavement compared to their counterparts, whose self-rated health declined as the loss neared but later recovered to exceed prior levels. These findings shed new light on the dynamics of immune function in response to spousal bereavement after dementia caregiving: longitudinal data reveal a pattern of health recovery following caregivers' loss, particularly among those with more robust social networks prior to bereavement.