Objective: To determine the treatment pattern and impact on healthcare costs of anxiety disorders and major depressive disorder (MDD), and influence of their concomitance and subsequence.
Methods: A retrospective cohort study was conducted using a US reimbursement claims database. Adult patients with an incident diagnosis of anxiety or MDD (index date) were included. Their sociodemographic data, diagnoses, healthcare resource use and associated costs were collected over the 6 months preceding and 12 months following index date.
Results: A total of 599,624 patients were identified and included. Patients with phobia or post-traumatic stress disorder had the highest 12-month costs ($8,442 and $8,383, respectively). Patients with social anxiety disorder had the lowest costs ($3,772); generalized anxiety disorder ($6,472) incurred costs similar to MDD ($7,170). Costs were substantially increased with emergence of anxiety during follow-up in MDD patients ($10,031) or emergence of MDD in anxiety patients ($9,387). This was not observed in patients with both anxiety and MDD at index date ($6,148).
Conclusion: This study confirms the high burden of costs of anxiety, which were within the same range as MDD. Interestingly, the emergence of anxiety or MDD in the year following a first diagnosis of MDD or anxiety, respectively, increased costs substantially. Major limitations were short follow-up and lack of absenteeism costs.