Healthcare Costs Associated With Chronic Opioid Use and Fibromayalgia Syndrome.

BACKGROUND

Fibromyalgia (FM) is an idiopathic, functional syndrome characterized by chronic, widespread pain and diffuse tenderness. This disorder affects more than 6 million patients in the United States and is associated with significant clinical and economic burdens.

OBJECTIVES

The objectives of this study were to: 1) estimate the costs associated with a FM diagnosis; and 2) estimate the impact of chronic opioid use on the costs of FM patients.

RESEARCH

DESIGN

Case-control study.

METHODS

Subjects were identified in a large nationally representative database of commercially insured patients. Propensity score-matched analyses included 445,912 FM-control pairs in the first analysis, while the second analysis included 48,333 chronic opioid users with the FM-control pairs. Primary outcomes of interest were the medical and prescription costs compared between matched pairs, based on propensity for being a case as evidenced by coefficients obtained from a first-stage logistic regression. Patient characteristics considered include: state of residence, diagnosing provider type, comorbid conditions, and concurrent medication use.

RESULTS

When controlling for propensity to receive a FM diagnosis, the actual diagnosis has a small effect on medical (-$83.54 [95% CI, -152.55 to -16.53]) and prescription ($120.31 [95% CI, 109.98-130.62]) costs. However, the effect of chronic opioid use in FM patients on medical ($9094.05 [95% CI, 8924.79-9263.31]) and prescription ($3391.81 [95% CI, 3368.84-3414.79]) costs is much more substantial.

CONCLUSIONS

While the differences seen in FM patients and controls are marginal, those attributed to chronic opioid use in these patients are significantly higher. Chronic opioid therapy to treat FM is a practice based not on evidence available to practitioners, but on other variables.