Spousal bereavement, mortality and risk of negative health outcomes among older adults: a population-based study

Lucas Morin; Jonas W Wastesson; Stefan Fors; Neda Agahi; Kristina Johnell

There is much debate about the nature of the relationship between spousal loss and subsequent adverse health outcomes. First, is the observed increase in the risk of death truly the consequence of bereavement, or is it-at least partly-attributable to phenotypical similarities between deceased individuals and their surviving spouse? For instance, assortative mating, convergence in lifestyle and shared environment throughout adulthood may very well be at play. 14 Previous studies have often been unable to convincingly establish a causal link between bereavement and mortality because of a lack of information on socioeconomic and health-related confounders at the time of spousal loss. 3 Second, is the potential effect of bereavement mainly fuelled by acute factors that influence health immediately after spousal loss or is it a mostly silent and prolonged process that accumulates over time? Although there is some evidence that the mortality risk associated with the loss of a partner is highest during the first year after widowhood and becomes weaker as time elapses, little is known about the exact shape of this association over time. 3, 15, 16 Third, does the potential effect of spousal bereavement on physical health extend beyond mortality? Prior research has shown that compared with non-bereaved individuals those who recently lost a spouse may have a higher risk of acute cardiovascular events. 17 However, the only large study published to date on this topic 18 relied exclusively on electronic records from primary care without linkage to hospital diagnoses or causes of death, thereby potentially underestimating the actual number of cases. Fourth, most studies have examined the association between widowhood and mortality without differentiating the end-of-life trajectory of the deceased spouse. For instance, are older persons whose spouse died from dementia (often preceded by a long period of informal care) at greater excess risk of negative health consequences than those who lost their partner from another cause of death? Investigating potential differences between illness trajectories is an important step to identify caregivers at high risk of adverse health events and to design targeted interventions. Finally, there is a need to evaluate health outcomes longitudinally, both before and after spousal loss. Measuring withinindividual changes in the risk of experiencing negative health outcomes would allow for disentangling the potential effect of bereavement from that of pre-bereavement experiences such as caring for a seriously ill spouse near the end of life. [19] [20] [21] The present study aimed to overcome some of the limitations of previous work by addressing each of these five issues. We examined the risk of death and adverse health outcomes associated with spousal bereavement among community-dwellers aged 65 years and older by analysing routinely collected administrative and healthcare data with two different epidemiological designs (matched cohort and selfcontrolled cohort crossover) and by applying a variety of methods to assess and mitigate the risk of bias inherent to the observational nature of the study.