Real-world role of tricyclic antidepressants in the treatment of fibromyalgia.

OBJECTIVE

To examine the real-world role of tricyclic antidepressants (TCAs) in fibromyalgia (FM) treatment.

METHODS

Using privately insured U.S. administrative claims data, this study examined TCA use for newly diagnosed FM patients. Patients ages 18 to 64 years with ≥ 2 FM diagnoses (ICD-9-CM: 729.1) during Q1:2007 to Q1:2009, no previous FM diagnosis, and continuous eligibility for insurance during the year before and after the first FM diagnosis ("study period") were identified as newly diagnosed (N = 10,129). Treatment with TCAs was examined over the first treatment episode (allowing up to a 45-day gap between refills). A sensitivity analysis was performed excluding patients with depression/anxiety diagnoses during the study period.

RESULTS

During the study period, 8.9% of patients with FM used TCAs at anytime, 5.0% used TCAs during the year before FM diagnosis, and 7.2% used TCAs during the year after. The mean (median) duration of the first treatment episode was 150 (58) days. During this episode, 84.0% used other medications concomitantly, with 60.3% using analgesics and 39.6% using other antidepressants. Additionally, 60.8% augmented TCA use with other drugs, 61.8% switched to another drug at the end of their TCA episode, and 22.8% discontinued TCAs without switching. Similar patterns were observed for the subset of patients with no depression or anxiety (N = 7,655).

DISCUSSION

Research covering 1999 to 2005 using the same methods found that 15.9% of patients with FM used TCAs during the year before FM diagnosis and 20.7% used TCAs during the year after. These findings suggest that TCA use among the patients with FM is uncommon and may be declining in real-world practice.