Health services costs and their determinants in women with fibromyalgia

Abstract

Objective: Patients with fibromyalgia (FM) use health services extensively. Knowledge about costs of FM is limited because of non-inclusiveness in assessing direct costs, because attempts to assess indirect costs are largely absent, and because determinants of costs have yet to be identified. We investigated the 6-month costs (direct and indirect) in women with primary FM, and we identified determinants of direct costs.

Methods: Subjects (n = 180 women) completed a health resource questionnaire as well as measures of pain, psychological distress, comorbidity, and disability. Unit costs for resources were obtained from government, hospital, laboratory, and professional association sources. Regression modeling for 6-month direct cost included age, disability, comorbidity, pain intensity, psychological distress, education, and work status.

Results: The average 6-month direct cost was $CDN 2298 (SD 2303). The largest components were medications ($CDN 758; SD 654), complementary and alternative medicine (CAM; $CDN 398; SD 776), and diagnostic tests ($CDN 356; SD 580). Our most conservative estimate of average 6-month indirect cost was $CDN 5035 (SD 7439). Comorbidity and FM disability were statistically significant contributors to direct costs in the multivariate analysis. Costs increased by approximately 20% with each additional comorbid condition.

Conclusion: Women with FM are high consumers of both conventional and CAM services. Our estimates of costs exceed those from most other studies; this may be due to our inclusion of a broader set of health services, medications, and indirect costs. Although in univariate analyses the number of comorbidities and indices of the effect of FM, psychological distress, and pain intensity were associated with higher direct cost, in a multiple regression analysis, only the measure of FM disability and the number of comorbidities were significant direct-cost determinants. FM also imposes important indirect costs, which were nearly 70% of the economic burden.