Comorbidity, Pain Medication Burden Seen in Patients with Fibromyalgia Newly Prescribed Pregabalin or TCAs

AUSTIN, TX—Patients with fibromyalgia (FM) who were prescribed pregabalin and tricyclic antidepressants (TCAs) demonstrated a considerable comorbidity and pain medication burden, investigators reported during the American Pain Society's 30th Annual Scientific Meeting. In fact, medication use and costs increased in the follow-up period for both cohorts.

“Despite our attempts to control for bias through propensity score-matching, the higher preindex total costs in the pregabalin cohort suggest a potential channeling of more severe patients to pregabalin,” said Arthi Bala Chandran, MPH, and colleagues of Avalon Health Solutions, Philadelphia, PA. The study used the LifeLink Health Plan Claims Database to evaluate treatment patterns among patients with FM who were newly prescribed pregabalin or TCAs (n=898; mean age 48.5±9.9 years) in clinical practice. These patients were propensity score-matched (PSM) with those initiated on pregabalin (n=898; mean age 47.9±9.6 years).

Date of the first pregabalin or TCA prescription was noted and comorbidities, pain-related pharmacotherapy, and healthcare resource use and healthcare costs were examined during the 12 months before (preindex) and after (follow-up) this date. Investigators evaluated the use of concomitant NSAIDs, COX2-inhibitors, muscle relaxants, antidepressants (SSRIs, SNRIs), benzodiazepines, and sedative hypnotics.

The investigators found both cohorts had multiple comorbidities and a substantial pain medication burden in both the preindex and follow-up periods. More than 90% of patients in each group had a comorbid musculoskeletal pain condition; low back pain was the most frequently reported.

Among patients prescribed pregabalin, use of nonselective NSAIDs (43.3% vs 39.8%), other anticonvulsants (28.6% vs 23.3%), and tetracyclic or miscellaneous antidepressants (28.5% vs 25.8%) was significantly decreased in the follow-up period, while use of COX-2 inhibitors (7.7% vs 10.4%), TCAs (4.8% vs 7.9%), and topical agents (10.8% vs 15.1%) all increased (all P<0.05). Among patients prescribed TCAs, significant decreases were found for muscle relaxants (42% vs 38.4%) and sedative hypnotics (27.4% vs. 23.9%) and increases for COX-2s (5.8% vs 7.9%) and anticonvulsants (25.1% vs 33.7%; all P<0.05).