Changes in Bone Formation Markers Observed Among Patients With Early Axial Spondyloarthritis

Among patients with early axial spondyloarthritis (axSpA), an increase in serum bone morphogenetic protein (BMP)-7 over 5 years was found to be linked to inflammation and was increased with active disease, but the increase was low with tumor necrosis factor (TNF) inhibitor treatment, according to study results published in Rheumatology. In addition, levels of serum sclerostin increased over time, but the increase was less pronounced than for serum BMP-7.

Studies have shown that patients with advanced axSpA are at risk for ectopic new bone formation with spine ankylosis, but are also prone to increased bone loss secondary to inflammation. Pathways associated with bone formation may change over time; the objective of the current study was to explore the 5 year changes in bone formation modulators (sclerostin and dickkopf-1) and markers (BMP-7) in early axSpA.

Using data from Devenir des Spondyloarthropathies Indifferenciees

Recentes (DESIR), a national multicenter cohort of patients with suspected axSpA, researchers assessed the changes in serum levels of BMP-7, sclerostin and dickkopf-1 at baseline and after 2 and 5 years.

The study sample included 708 patients (46.2% men; mean age, 33.7 years) in the DESIR cohort with symptoms suggestive of axSpA based on rheumatologist assessment. Of these patients, 258 (36.4%) received treatment with at least 1 TNF inhibitor during the first 5 years of the cohort.

At 5 years, serum BMP-7 levels significantly increased relative to baseline (median increase of 223.7%; P <.001). The increase was more pronounced among men and among patients with active disease, according to Ankylosing Spondylitis Disease Activity Score with CRP ≥1.3. However, the increase was low with use of TNF inhibitors (P <.001). Serum sclerostin levels increased over time (median, 14.8%; P <.001). In univariate analysis, the increase was more pronounced among men, but less among smokers. However, in multivariable analysis, no determinant was associated with serum sclerostin change. With regard to dickkopf-1, no statistically significant change was evident in serum levels over 5 years (P =.09).

The study had several limitations, including a decrease in the number of patients attending all visits during 5 years, inclusion of patients with early axSpA with minor structural damage, and the lack of data on physical activity levels.

“This study showed that serum BMP-7 significantly increased over time and these changes are significantly high in active disease but low with TNF [inhibitor] use. More studies with a longer follow-up will be needed to confirm these results and to assess the structural impact of the bone formation markers changes,” the researchers concluded.

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Descamps E, Molto A, Borderie D, et al. Changes in bone formation regulator biomarkers in early axial spondyloarthritis. Published online September 5, 2020. Rheumatology (Oxford). doi:10.1093/rheumatology/keaa296