Anxiety and Depressive Disorders in Older Primary Care Patients: Defining a Clinical Severity Gradient Corresponding to Differences in Health Status, Functioning, and Health Service Use

Abstract

Anxiety and depression are common psychiatric disorders affecting older persons. To explore the relationships between these disorders and client characteristics, we examined data from the baseline phase of PRISM-E, a multisite randomized trial comparing two models of service delivery for older persons aged 65 and over identified in primary care settings with depression, anxiety, and/or at-risk drinking. Clinical characteristics, functioning and service use were compared across five diagnostic groups of study participants (n = 1,763; mean age = 73.8 ± 6.3 years, 71% male) with (1) anxiety only (n = 82), (2) minor/other depression (n = 502), (3) major depression (n = 700), (4) mixed minor/other depression and anxiety (n = 121), and (5) mixed major depression and anxiety (n = 358). Increasing functional problems and use of services were found across the five diagnostic subgroups, corresponding to a gradient of increasing severity for health status, number of medical disorders, SF-36 mental component score, suicidal or death ideation, and number of hospital stays, emergency room visits, and outpatient medical visits. Multivariate analyses controlling for site, demographic variables, and clinical characteristics confirmed the observed clinical severity gradient. Anxiety alone and anxiety comorbid with depression represent the two extremes of the severity gradient from the least to the most complicated and severe clinical presentations. Primary care clinicians identifying anxiety disorders in older persons should also screen for depression due to the relative infrequency of anxiety disorder alone and the significant clinical implications of co-occurring anxiety and depression.