Isolation, Not Loneliness or Cynical Hostility, Predicts Cognitive Decline in Older Americans.

Objective: To jointly examine isolation, loneliness, and cynical hostility as risk factors for cognitive decline in older adults. Method: Data came from the 2006 to 2012 waves of the Health and Retirement Study (HRS), a longitudinal study of U.S. older adults (age ⩾ 65 years, n = 6,654). Measures included frequency of contact with social network (objective isolation), the Hughes Loneliness Scale (loneliness), a modified version of the Cook-Medley Hostility Inventory (cynical hostility), and a modified version of the Telephone Interview for Cognitive Status (cognitive function). Multilevel modeling (random slope + intercept) was used to examine the association between these factors and trajectories of cognitive function. Results and Discussion: After controlling for demographic characteristics, self-reported health, and functional limitations, loneliness (β = -.34, 95% confidence interval [CI] = [-0.56, -0.11), and cynical hostility (β = -.14, 95% CI = [-0.24, -0.04) correlated with lower cognitive function, but none predicted change in cognitive function. Objective social isolation was associated with lower cognitive function (β = -.27, 95% CI = [-0.41, -0.12]) and steeper decline in cognitive function (β = -.09, 95% CI = [-0.16, -0.01]).