Researchers Identify Predictors of Spinal Damage in Spondyloarthritis

Newswise — CHICAGO – The presence of syndesmophytes (bony growths in the spine), acute phase reactants (proteins that are released into the blood in response to inflammation), and smoking status can all serve as predictors for the progression of structural damage in the spine in people with spondyloarthritis, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Chicago.

Spondyloarthritis is the overall name for a family of inflammatory rheumatic diseases that can affect the spine, joints, ligaments and tendons. These diseases can cause pain and stiffness in the back and neck as well as pain and swelling of the joints and inflammation of the eyes, skin, lungs, and heart valves. While there is no way to prevent these diseases, early treatment by a rheumatologist can reduce pain, stiffness and loss of functionality.

Within the spondyloarthritis family is axial spondyloarthritis – a disease that affects the axial skeleton, the spine and/or sacroiliac joints (joints between the pelvis and the spine). In its more severe form, known as ankylosing spondylitis, radiographic changes may be identified in the spine and sacroiliac joints. Less severe, or earlier, axial spondyloarthritis may present with symptoms but no radiographic damage (non-radiographic axial spondyloarthritis).

While there have been some studies on risk factors of progression of structural damage (such as the development of syndesmophytes) in people with longstanding ankylosing spondylitis, there is very little data on people who have early spondylarthritis, and researchers recently investigated predictors of progression of structural damage in a group of people with ankylosing spondylitis and a group with non-radiographic axial spondyloarthritis.

Led by Denis Poddubnyy, MD, PhD; Martin Rudwaleit, MD, PhD; and Joachim Sieper, MD, PhD, researchers studied 210 people with early spondylarthritis. Of these, 115 had ankylosing spondylitis with less than 10 years of symptoms and 95 had non-radiographic axial spondyloarthritis with less than five years of symptoms. All patients had X-rays taken of the lumbar and cervical spine at the beginning of the study and again two years later. These X-rays were read by two trained readers who — without knowledge of when the X-rays were taken or the health history of the patients — scored each one for structural changes such as erosions, sclerosis, vertebral squaring (caused by formation of new bone at the corners of spinal vertebrae) and syndesmophytes.

The researchers were looking for significant worsening in the resulting score, which would indicate progression of the structural damage in the spine. Among the entire study group, researchers noted significant progression of structural damage in the spine in just over 14 percent of the patients. When broken down, those with ankylosing spondylitis who already had radiographic changes at the beginning of the study showed a higher rate (20 percent) of progression than those with non-radiographic axial spondyloarthritis (just over seven percent).

After noting the percentages of patients who showed progression of structural damage, the researchers began to look into the potential predictors of damage progression. Among others, the following predictor candidates were studied: presence of syndesmophytes at the beginning of the study, sex, presence of a specific genetic marker called HLA-B27, acute phase reactants reflecting activity of inflammation, and smoking status. And, among these, only the presence of syndesmophytes at the beginning of the study, elevated acute phase reactants, and cigarette smoking were able to independently predict progression of the structural damage in the spine after two years.

“Although syndesmophytes, once occurred, cannot regress, two other factors related to structural damage in the spine – active inflammation and cigarette smoking – were identified, which could be potentially modified,” says Dr. Poddubnyy of the findings. “This indicates that effective anti-inflammatory treatment and smoking cessation — especially done at the early stage — might interfere with the course of the disease, retard development of structural damage in the spine, and improve outcome in patients with axial spondyloarthritis.”

The American College of Rheumatology is an international professional medical society that represents more than 8,000 rheumatologists and rheumatology health professionals around the world. Its mission is to advance rheumatology. The ACR/ARHP Annual Scientific Meeting is the premier meeting in rheumatology. For more information about the meeting, visit www.rheumatology.org/education. Follow the meeting on Twitter by using the official hashtag: #ACR2011.

Editor’s Notes: Denis Poddubnyy, MD, PhD, will present this research during the ACR Annual Scientific Meeting at the McCormick Place Convention Center at 2:30 PM on Sunday, November 6 in Room W470b. Dr. Poddubnyy will be available for media questions and briefing at 1:30 PM on Tuesday, November 8 in the on-site press conference room, W 175C.

Learn more about living well with rheumatic disease as well as rheumatologists and the role they play in health care. Also, discover the ACR’s Simple Tasks campaign, which highlights how rheumatic diseases strike women disproportionately and in the prime of their lives.

Presentation Number: 777

Baseline Radiographic Damage, Elevated Acute Phase Reactants and Cigarette Smoking Status Predict Radiographic Progression in the Spine in Early Axial Spondyloarthritis

Denis Poddubnyy1 (Charité Medical University, Campus Benjamin Franklin, Berlin, Germany)Hildrun Haibel2 (Charité Campus Benjamin Franklin, Berlin, Germany)Joachim Listing3 (German Rheumatism Research Centre, Berlin, Germany)Elisabeth Märker-Hermann4 (Dr. Horst Schmidt Kliniken, Wiesbaden, Germany)Henning Zeidler5 (Medizinische Hochschule, Hannover, Germany)Jürgen Braun6 (Rheumazentrum Ruhrgebiet, Herne, Germany)Joachim Sieper2 (Charité Campus Benjamin Franklin, Berlin, Germany)Martin Rudwaleit7(Ev. Krankenhaus Hagen-Haspe, Hagen, Germany )

Background/Purpose: There are some data available on the frequency of structural damage in the spine in patients with ankylosing spondylitis (AS) and about potential risk factors for the development of syndesmophytes, but these data refer exclusively to patients with longstanding AS. Nearly no data exist regarding rates and predictors of radiographic spinal progression in early axial spondyloarthritis (SpA). The objective of the study was to investigate rates and predictors of structural damage development in the spine in patients with early axial SpA (AS with symptoms duration of <10 years and non-radiographic axial SpA (nrSpA) with symptoms duration of <5 years).

Method: 210 patients with axial SpA (115 with AS according to the modified New York criteria and 95 with nrSpA) from the German Spondyloarthritis Inception Cohort (GESPIC) were selected for this analysis based on availability of radiographs (sacroiliac joints, lumbar and cervical spine lateral views) at baseline and after 2 years of follow-up. Images were centrally collected, digitized, and subsequently scored independently by two trained readers. Spinal radiographs were scored according to the mSASSS scoring system. The readers scored both time points simultaneously but were blinded for the time point and for all clinical data. Significant radiographic spinal progression was defined as a worsening of the mean mSASSS score by ≥2 units over two years

Result: Altogether, 14.3% of the patients in the whole SpA group showed spinal radiographic progression according to this definition. This rate was higher in the group of patients with AS (20%) in comparison to non-radiographic axial SpA (7.4%). The following parameters were independently associated with radiographic spinal progression: presence of syndesmophytes at baseline (odds ratio (OR)=6.29, p<0.001), elevated markers of systemic inflammation (erythrocyte sedimentation rate: OR=4.04, p=0.001, C-reactive protein: OR=3.81, p=0.001), and cigarette smoking (OR=2.75, p=0.012), that was confirmed in the multivariate logistic regression analysis. No clear association with radiographic spinal progression was found for HLA-B27 status, sex, age, disease duration, BASDAI, BASFI, presence of peripheral arthritis, enthesitis or psoriasis. Based on the obtained data two prediction matrix models were constructed incorporating the following variables: baseline syndesmophytes, smoking status and an elevated acute phase reactant (either ESR or CRP) – figure.

Conclusion: The presence of radiographic damage in the spine (syndesmophytes), elevated acute phase reactants and cigarette smoking status predict spinal radiographic progression in early axial SpA.

Disclosure: D. Poddubnyy, None; H. Haibel, None; J. Listing, None; E. Märker-Hermann, None; H. Zeidler, None; J. Braun, None; J. Sieper, None; M. Rudwaleit, None.