Loneliness and functional limitations among older adults with diabetes: Comparing directional models

Middle-aged and older adults with diabetes are at increased risk for loneliness and functional limitations. Cross-sectional and longitudinal associations between loneliness and functional limitations have been demonstrated among the general population, but have not been established among those with diabetes. The purpose of this study was to directly compare the following models describing the direction of the association between loneliness and functional limitations among people with diabetes: (1) loneliness leads to functional limitations, (2) functional limitations lead to loneliness, and (3) a bidirectional association between loneliness and functional limitations.

Data came from the Health and Retirement Study. Participants were middle-aged and older individuals with diabetes in the United States (n = 2934). Loneliness and functional limitations were measured at baseline, 4-year follow-up, and 8-year follow-up. Path models for each of the three models, as well as a stability model, were created. Model fit was compared using Akaike's Information Criteria (AIC).

Participants were 54.6% female, 74.98% White, had a mean age of 69.66 years, had an average of 1.48 comorbid chronic conditions, and had diabetes for an average of 10.40 years. The bidirectional model best fit the data as evidenced by the lowest AIC value (AIC = 171,162.81). ∆AIC between the bidirectional model and the next best fitting model was 16.19, indicating strong support for selecting the bidirectional model. Higher levels of loneliness were associated with subsequent higher levels of functional limitations at some time points (βs = 0.07, 0.02) and higher levels of functional limitations were associated with subsequent higher levels of loneliness (βs = 0.13, 0.06) at all time points.

Results suggest that the association between loneliness and functional limitations among individuals with diabetes is bidirectional. This study demonstrates the value of directly comparing directional models.