Executive dysfunction, heart disease burden, and remission of geriatric depression

This study investigated the relationship of executive impairment and heart disease burden to remission of major depression among elderly patients. A total of 112 elderly subjects suffering from major depression received treatment with citalopram at a target daily dose of 40 mg for 8 weeks. Diagnosis was assigned using the Research Diagnostic Criteria and the DSM-IV Criteria after an interview with the Schedule for Affective Disorders and Schizophrenia. Executive dysfunction was assessed with the Initiation/Perseveration subscale of the Dementia Rating Scale (DRS) and the Color-Word Stroop test. Medical burden, including heart disease burden, was rated with the Cumulative Illness Rating Scale, and disability with Philadelphia Multilevel Instrument. Both abnormal initiation/perseveration and abnormal Stroop scores were associated with low remission rates of geriatric depression. Similarly, heart disease burden and baseline severity of depression also predicted low remission rates. The relationship of heart disease burden to remission was not mediated by executive dysfunction. Impairment in other DRS cognitive domains, disability, medical burden unrelated to heart disease did not significantly influence the outcome of depression in this sample. Executive dysfunction and heart disease burden constitute independent vulnerability factors that increase the risk for chronicity of geriatric depression. The findings of this study provide the rationale for investigation of the role of specific frontostriatal-limbic pathways in predisposing to geriatric depression or worsening its course.