The Moderating Effect of Age on the Association Between Circadian Syndrome and Instrumental Activities of Daily Living Disability in People With Diabetes: A Cross-Sectional Study

PURPOSE: To examine the association between circadian syndrome (CircS) and instrumental activities of daily living (IADL) disability in middle-aged and older adults with diabetes, as well as the moderating effect of age on CircS and IADL disability. METHOD: Participants included 939 individuals with diabetes. IADL disability was defined as having trouble finishing specific tasks. CircS was defined as having four or more specific symptoms. Binary logistic regression analysis was used to examine associations among CircS, age, and IADL disability. RESULTS: Of total participants, 29.3% had IADL disability. CircS and age were associated with IADL disability (CircS: odds ratio [OR] = 1.898, 95% confidence interval [CI] [1.370, 2.630]; age: OR = 1.045, 95% CI [1.027, 1.063]; both p < 0.001). The interaction effect of age on CircS and IADL disability was significant (OR = 1.047, 95% CI [1.004, 1.092], p = 0.032). CONCLUSION: Individuals with diabetes and CircS had a higher risk of IADL disability than those without CircS, and the difference in predicted probabilities of IADL disability between the two groups increased with age. [Journal of Gerontological Nursing, 51(4), 37-45.].