Methodological Considerations for Comorbidity of Anxiety and Depression in Later-Life Psychotherapy Trials: A Scoping Review

OBJECTIVES: Anxiety and depression are highly comorbid in older adults, especially considering subthreshold symptom presentations. Psychotherapies treating both conditions in this population are not well established. This scoping review aimed to quantify how frequently psychotherapy trials for anxiety/depression in older adults utilize measures of the other disorder and describe methodology pertaining to comorbidity. METHODS: Articles were screened by two reviewers at all stages. Articles published between January 2010 and November 2024 were searched; eligible articles used randomized control (RCT) designs, primarily enrolled older adults, evaluated a psychotherapy for anxiety and/or depression, and included anxiety and/or depression as primary outcomes. RESULTS: In total, 1,066 studies were screened at the title/abstract stage, 264 at the full text stage, and 91 were included. While most RCTs for anxiety included depression outcomes, only a minority of depression trials assessed anxiety. No trials accounted for comorbidity or presence of the other disorder in their primary statistical analyses. CONCLUSIONS: Though highly comorbid in practice, most RCTs for anxiety/depression in older adults do not measure the other disorder. CLINICAL IMPLICATIONS: Current RCTs of anxiety/depression in later life overlook the reality of comorbidity and complex symptom presentations. Future trials should attend to comorbidity and consider transdiagnostic treatments.