16. Assessing the Impact of Comorbid Depressive and Anxiety Symptoms on Severity of Functional Impairment in a Nationally Representative Sample

Introduction: Performing self-care and domestic life tasks are key measures of functional independence for older adults. While both depression and anxiety symptoms have been correlated with increased functional limitation, these two disorders are most often studied separately, despite frequent co-occurrence and plausible interactive effects. This study examined the impact of comorbid depressive and anxiety symptoms on the severity of functional limitation in a nationally representative sample of older adults.

Methods: The National Social Life, Health, and Aging Project (NSHAP) data was utilized for this study. The primary outcomes were self-reported severity with activities of daily living and instrumental activities of daily living. A composite measure of mental health was created based on reports of frequent depressive and anxiety symptoms. All analyses were weighted to account for the complex sampling design of NSHAP and conducted in R.

Results: Respondents were 53.9% female, with a median age of 62 years. Approximately one-third of respondents documented either depressive or anxiety symptoms, with 11% documenting both. Those with both depressive and anxiety symptoms reported the greatest number of functional limitations, and the greatest difficulty with the tasks assessed. In a multivariate linear regression, worse mental health status, greater age, increased comorbidity burden, and reduced income significantly predicted the severity of functional limitation. Depressive symptoms with and without anxiety symptoms were significantly associated with increasing severity of functional limitation when compared to those without either depressive or anxiety symptoms.

Impact: To create policy and individual-level interventions that best support functional status over the entire life course, it is vital that we understand the impact of comorbid depression and anxiety on functional status. These results build on existing literature calling for a more holistic assessment of health – both physical and mental – and further emphasizes the need for transdiagnostic mental health interventions as an avenue to increase functional independence in older adults.

Organization: Saint Louis University

DeMarco EC, Hinyard L, Subramaniam DS