Sibling Disconnectedness in Midlife and Cognitive Functioning in Later Life: Is Loneliness an Explanatory Factor?

ObjectivesSibling ties are among the most enduring of all social relationships, so the loss or absence of this long-standing bond may undermine the well-being of older adults. This study examined whether and how disconnectedness from adult siblings (i.e., no contacts/interactions and emotional distance) is linked to older adults' cognitive functioning.MethodsWe use data from four waves of the Wisconsin Longitudinal Study (1993-2020) and structural equation models to prospectively evaluate the association between sibling disconnectedness and cognition, and the extent to which this association is mediated by loneliness. Participants reported on sibling disconnectedness in 1993/age 54 and 2004/age 65, and on loneliness in 2011/age 72. Cognition was evaluated in 2020/age 81.ResultsPersistent sibling disconnectedness was not directly associated with cognitive decline, but it was significantly and indirectly associated with cognition through loneliness.ConclusionsOur findings underscore the importance of sibling relationships as a source of social support and cognitive engagement in midlife.