Risk of stroke after bereavement-a systematic literature review

Several studies have suggested that psychological stress may increase the risk of stroke. However, this link remains a controversial issue because of conflicting findings. Bereavement, the loss of a close relative, is considered a severely stressful life event. Increased risk of stroke could thus be expected after bereavement if stress plays a causal role. We aimed to evaluate the association between bereavement and stroke by performing a systematic review of the existing literature. The literature search was conducted according to the PRISMA guidelines for systematic reviews. A search in Medline and Embase identified eligible studies, which were reviewed by two researchers independently according to specific inclusion criteria. We included six studies: five cohort studies and one case-crossover study. Five studies found that loss of a first-degree relative was associated with a 1.1- to 2.4-fold higher risk of stroke. However, one study found a statistically significant overall risk only for women. Five studies evaluated the risk of stroke according to time since the loss; one study found no association, two studies indicated short-term effect, one study indicated long-term effect, and one study indicated both short-term and long-term effect. Three studies stratified their analysis by sex; two found higher association in bereaved women than men. Our systematic review suggests that bereavement-related stress is associated with a higher risk of stroke. As relatively few studies were identified, new studies are needed to verify this association. These should aim to quantify the risk, describe the effect of time since bereavement, and identify risk-modifying factors.