Defining Anxious Depression in Later Life: A Scaring Heterogeneity in Results

Background Anxiety in depression is challenging as it results in more functional impairment and a worse prognosis. No consensus exists on the definition of anxious depression. Methods In 359 older patients with major depressive disorder, we examined the agreement between anxious depression based on different combinations of comorbid anxiety disorders and anxious depression based on high level of anxiety symptoms measured by self-report questionnaires. Results Agreement between the definitions of anxious depression was poor, as indicated by κ statistics ranging between 0.06 and 0.23. Conclusion Accepted criteria for anxious depression classify completely different patients as being anxious depressed. This may explain inconsistent results of previous studies on anxious depression. Moreover, progress in this research field is hampered, as studies using different definitions cannot be pooled in meta-analyses.