ab222013

Antipolymer antibodies in Danish fibromyalgia patients

B. Jensen^1,2, I. Hechmann Wittrup¹, A. Wiik³, H. Bliddal¹, S. Friis², J.K. McLaughlin^4,5, B. Danneskiold-Sams¿e¹, J.H. Olsen^2,5

¹Parker Institute, Frederiksberg Hospital, Frederiksberg, Denmark; ²Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen; ³Department of Autoimmunology, Statens Serum Institut, Copenhagen, Denmark; ⁴International Epidemiology Institute, Rockville, Maryland; ⁵Department of Medicine, Vanderbilt University Medical Center, Vanderbilt-Ingram Cancer Center, Nashville, Tennessee, USA.

ABSTRACT
Objective
To use a new immunologic assay to investigate antipolymer antibody (APA) levels in women with fibromyalgia (FM).

Methods
The study population consisted of 35 patients with FM and 129 controls. The controls were selected based on a prior history of breast surgery and the presence or absence of a prior hospital diagnosis of soft tissue rheumatism. Study subjects underwent blood sampling, including tests for antinuclear antibodies (ANA) and APA, a clinical examination, and an interview focusing on rheumatic complaints and self-reported disability. The severity of rheumatic symptoms/signs was scored from 1 (= none) to 5 (= severe) based on the clinical examination and the interview.

Results
FM patients in this study represented a broad spectrum of disease severity, with the majority having mild symptoms. FM patients had a higher symptom severity and myalgic scores than controls (p < 0.001 for both variables). Adjusting for symptom severity, a weak positive association between APA levels and FM was observed (p = 0.08). The APA level was inversely associated with age, i.e., decreasing APA levels were seen with increasing age (p = 0.008).

Conclusion
FM patients tended to have slightly higher APA levels than controls when adjusted for symptom severity. APA levels declined with age, a finding that has not been reported previously. The APA test and its clinical relevance should be evaluated in future studies.

Key words
Antipolymer antibodies, fibromyalgia, symptom severity, myalgic score, antinuclear antibodies

Please address correspondence to: Bente Jensen, MD, PhD, P.G. Ramms AllŽ no. 1, 3 th., 2000 Frederiksberg, Copenhagen, Denmark.
(reprints will not be available from the author)
E-mail: bjensen@aab11.dk