Association between Activities of Daily Living and Depression in Older Adults with Diabetes: A Case-Control Study

Background: Older adults with diabetes often experience functional limitations in their ability to perform daily activities, potentially increasing their vulnerability to mental health issues such as depression. Understanding this association is vital for enhancing care strategies. Methods: A population-based case-control study was conducted using data from the Sina Health Information System (SINAEHR) between 2017 and 2024 in Mashhad, Iran. Cases included older diabetic adults diagnosed with depression, while controls were age- and gender-matched diabetic individuals without depression. Key demographic and clinical factors including comorbidities, medication history, BMI, and social factors were analyzed using multivariable logistic regression to identify independent predictors. Results: Among 9,696 elderly individuals with diabetes, 2,424 (25%) were identified with depression. Impairment in activities of daily living (ADL) was the strongest independent predictor (AOR = 3.12). Moderate and severe ADL impairment were associated with significantly higher odds of depression (AOR = 4.42 and 3.90, respectively). Other independent risk factors included age 60–79, female gender (AOR = 2.05), urban residence (AOR = 2.5), higher education, unmarried status, smoking, Iranian nationality, and anxiety history. Depression was also significantly associated with clinical comorbidities such as hypertension, hyperlipidemia, thyroid disorders, cancer, kidney disease, and nervous system conditions. Conclusion: Functional limitations in ADLs are independently associated with an increased risk of depression in elderly diabetic patients. These findings underscore the need for integrated care models that address both physical function and mental health in this vulnerable population.