Subsyndromal depression and anxiety in older adults: health related, functional, cognitive and diagnostic implications.

Subsyndromal depression in later life is common in primary care. Comorbid anxiety disorders could exacerbate the negative effect of subsyndromal depression on functioning, health-related quality of life, comorbidity and/or cognition. We examined anxiety disorders co-existing with subsyndromal depression in participants ≥ age 50 in an NIH trial of Problem Solving Therapy for Primary Care for indicated prevention of major depression. There were 247 participants, with Centers for Epidemiologic Studies - Depression scores ≥ 11. Participants could have multiple psychiatric diagnoses: 22% of the sample had no DSM IV diagnosis; 39% of the sample had only 1 DSM IV diagnosis; 28% had 2 diagnoses; 6% had 3 DSM IV diagnoses; 4% had 4 DSM IV diagnoses; and 1% had 5 diagnoses. Furthermore, 34% of participants had a current comorbid DSM IV diagnosis of a syndromal anxiety disorder. We hypothesized that those with subsyndromal depression, alone relative to those with co-existing anxiety disorders, would report better health-related quality of life, less disability, less medical comorbidity and less cognitive impairment. However, there were no differences in quality of life based on the SF 12 nor in disability based on Late Life Function and Disability Instrument scores. There were no differences in medical comorbidity based on the Cumulative Illness Scale-Geriatrics scale scores nor in cognitive function based on the Executive Interview (EXIT), Hopkins Verbal Learning Test-Revised and Mini-Mental Status Exam. Our findings suggest that about one third of participants 50 years and older with subsyndromal depression have comorbid anxiety disorders; however, this does not appear to be associated with worse quality of life, functioning, disability, cognitive function or medical comorbidity.