Cost-utility analysis of a multicomponent intervention for fibromyalgia syndrome in primary care versus usual clinical practice: study protocol for an economic evaluation of a randomised control trial

Fibromyalgia: A Review of the Pathophysiological Mechanisms and Multidisciplinary Treatment Strategies

Fibromyalgia is a syndrome characterized by chronic widespread musculoskeletal pain, which may or may not be associated with muscle or joint stiffness, accompanied by other symptoms such as fatigue, sleep disturbances, anxiety, and depression. It is a highly prevalent condition globally, being considered the third most common musculoskeletal disorder, following lower back pain and osteoarthritis. It is more prevalent in women than in men, and although it can occur at any age, it is more common between the ages of thirty and thirty-five. Although the pathophysiology and etiopathogenesis remain largely unknown, three underlying processes in fibromyalgia have been investigated. These include central sensitization, associated with an increase in the release of both excitatory and inhibitory neurotransmitters; peripheral sensitization, involving alterations in peripheral nociceptor signaling; and inflammatory and immune mechanisms that develop concurrently with the aforementioned processes. Furthermore, it has been determined that genetic, endocrine, psychological, and sleep disorders may influence the development of this pathology. The accurate diagnosis of fibromyalgia remains challenging as it lacks specific diagnostic biomarkers, which are still under investigation. Nonetheless, diagnostic approaches to the condition have evolved based on the use of scales and questionnaires for pain identification. The complexity associated with this pathology makes it difficult to establish a single effective treatment. Therefore, treatment is multidisciplinary, involving both pharmacological and non-pharmacological interventions aimed at alleviating symptoms. The non-pharmacological treatments outlined in this review are primarily related to physiotherapy interventions. The effectiveness of physical exercise, both on land and in water, as well as the application of electrotherapy combined with transcranial therapy and manual therapy has been highlighted. All of these interventions aim to improve the quality of life of patients highly affected by fibromyalgia.

Cost-utility of a multicomponent intervention for fibromyalgia versus usual care: a pragmatic randomised controlled trial

OBJECTIVE

To perform an economic evaluation on a multicomponent intervention programme for patients with fibromyalgia syndrome compared with usual clinical practice in primary care.

DESIGN

A cost-utility analysis was conducted alongside a pragmatic randomised controlled trial (ClinicalTrials.gov: https://clinicaltrials.gov/ct2/show/record/NCT04049006) from a societal perspective, a human capital approach, and a 1-year time horizon.

PATIENTS

Patients diagnosed with fibromyalgia  syndrome from the public health system in south Catalonia, Spain.

METHODS

Crude and adjusted incremental cost- utility ratios were estimated to compare the treatment strategies based on cost estimations (direct medical costs and productivity losses) and quality-adjusted life years. One-way and 2-way deterministic sensitivity analyses were performed.

RESULTS

The final analysed sample comprised 297 individuals, 161 in the intervention group and 136 in the control group. A crude incremental cost-utility ratio of € 1,780.75 and an adjusted ratio of € 851.67 were obtained, indicating that the programme  significantly improved patients' quality of life with a cost-increasing outcome that fell below the cost-effectiveness threshold. The sensitivity analysis  confirmed these findings when  varying large cost components, and showed dominance when increasing session attendance.

CONCLUSION

The proposed multicomponent intervention programme was cost-effective compared with usual care for fibromyalgia, which supports its addition to standard practice in the regional  primary care service.