BMI but not age and sex negatively impact on the outcome of pharmacotherapy in fibromyalgia: a systematic review

ABSTRACT

Introduction

The impact of sex, age, body mass index (BMI) in fibromyalgia is still unclear. A systematic review was conducted to investigate whether sex, age and BMI influence the clinical outcomes and rate of adverse events.

Methods

The present study was performed according to the PRISMA guidelines. The literature search was performed in February 2021. All the RCTs investigating pharmacological strategies for fibromyalgia were accessed.

Results

Data from 51 RCTs (17,311 patients) were collected. Short Form 36 emotional, Social function and physical role subscales showed evidence of a negative association with BMI (P = 0.02, P = 0.002 and P = 0.0001, respectively). Depression and anxiety subscales of the Hospital Anxiety and Depression score demonstrated evidence of a positive association with age (P = 0.04 and P = 0.001, respectively) and sex (P = 0.00005 and P = 0.0001, respectively). Visual analog scale evidenced a positive association with BMI (P = 0.04). Clinical Global Impression Severity scale demonstrated evidence of a negative association with BMI (P = 0.02).

Conclusion

Irrespective from the pharmacological approach, a higher BMI is negatively associated with a favorable outcome in patients with fibromyalgia. The association with sex and age remains controversial.

Level of evidence

I, systematic review of RCTs.

KEYWORDS:

• Fibromyalgia
• age
• body mass index
• sex
• pharmacological management

Article highlights

• The impact of sex, age, body mass index in fibromyalgia is still unclear.

• Irrespective from the pharmacological approach, a higher body mass index is negatively associated with a favourable outcome in patients with fibromyalgia.

• The association with sex and age remains controversial. No association between age, sex, and body mass index with the occurrence of adverse events has been detected.

Acknowledgments

Arne Driessen and Giorga Colarossi have equally contributed to the completion of the present work and share the last position in the author list.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.