Axial Spondyloarthritis Doug White, Rheumatologist Waikato Hospital
Disclosures Presentations / Consulting Abbott Laboratories AbbVie MSD Novartis Roche Clinical Trials Abbott Laboratories AbbVie Actelion Ardea Bioscience Celgene Eli Lilly Galapagos Pfizer Roche Sanofi
None could define axial spondyloarthritis
When a patient presents with a history of low back pain and there are no abnormalities on the radiograph, I will refer this patient to the neurologist. It is very unlikely that I refer this patient to the rheumatologist. Provided that low back pain is the only symptom.
What is spondyloarthritis? Diagnostic criteria Epidemiology Mechanical vs inflammatory back pain Early detection Management
Psoriatic Arthritis Reactive Arthritis Undifferentiated Spondyloarthritis Spondyloarthritis Ankylosing Spondylitis Enthesitis Related Arthritis (JIA) Enteropathic Arthritis
Enthesitis - MRI
Inflammation to Ankylosis
Enthesitis: The Psoriatic Nail
Modified New York Criteria for AS Clinical Criteria Low back pain and stiffness for >3 months which improves with exercise and not with rest Limitation in spinal motion in frontal and saggital planes Limitation of chest expansion compared to norms for age and gender Radiographic criteria Radiographic sacroiliitis >Grade 2 bilaterally or >Grade 3-4 unilaterally AS confirmed if radiographic criterion and >1 clinical criterion met
Sacroiliitis on Plain Imaging and MRI
ASAS Axial Spondyloarthritis Criteria In patients with >3 months back pain and age <45 Sacroiliitis and >1 SpA feature OR HLA-B27 and >2 SpA features SpA Features Inflammatory back pain Psoriasis Anterior uveitis Inflammatory bowel disease HLA-B27 positive Dactylitis Enthesitis (heel) Good response to NSAIDs Family history of SpA Elevated CRP Sensitivity 89.2%, specificity 84.4%, n=649 Rudwaleit et al, Ann Rheum Dis, 2009
Spondyloarthritis: An Alternative Approach Spondyloarthritis Axial Spondyloarthritis (axspa) Peripheral Spondyloarthritis Non-radiographic axspa (nr-axspa) Radiographic axspa Clinical axspa
Progression from nr-axspa to AS
Parameter Non-radiographic axial SpA Radiographic axial SpA (AS) P Study Age, mean years 36.1 36.1 NS GESPIC 39.1 41.2 NS Herne Male sex, % 42.9 65.5 <0.001 GESPIC 31.8 76.8 <0.001 Herne 48.7 74.1 <0.001 SCQM HLA-B27 positive, % 74.7 73.1 NS GESPIC 86.4 89.1 NS Herne 78.5 82.5 NS SCQM Elevated CRP, % 29.8 49.6 0.001 GESPIC 29.5 69.1 <0.001 Herne 31.8 51.3 <0.001 SCQM Total pain, 0 10 4.8 4.8 NS GESPIC 4 5 NS Herne 6 6 NS SCQM Patient global assessment, 0 10 4.9 5 NS GESPIC 4 4.6 NS Herne 6 6 NS SCQM
Parameter Non-radiographic axial SpA Radiographic axial SpA (AS) P Study BASDAI, 0 10 3.9 4 NS GESPIC 3.6 4.3 NS Herne 5.1 4.8 0.05 SCQM BASFI, 0 10 2.5 3.1 0.027 GESPIC 1.5 2.9 NS Herne 2.7 3.3 NS SCQM BASMI, 0 10 1.1 1.9 <0.001 GESPIC 1 2 <0.001 SCQM Inflammatory lesions in the spine on MRI, % 9.1 44.6 0.01 Herne Treatment response to TNF antagonists* Non-radiographic Radiographic Parameter axial SpA axial SpA (AS) P Study ASAS40 response, % 65 75 NS ESTHER 57 48 NS RAPID-AxSpA 39 52 NS SCQM ASAS partial remission, % 60 40 NS ESTHER *TNF antagonists are not approved by Medsafe for the treatment of non-radiographic axial SpA in New Zealand
Cumulative Percentage Delay in diagnosis Age Average delay in diagnosis: 7 years
Implications In Argentina, 26% of those with AS are unemployed compared to 4.5% without In a Dutch study, withdrawal from work was 3x more likely if the person had AS Presenteeism Being at work but not performing well 77% say this was an issue for them
So, how can we pick up SpA earlier? Examination often unhelpful Lumbar side flexion first to change CRP can be normal in up to 40% Plain imaging is often normal early
So, how can we pick up SpA earlier? Inflammatory Back Pain is present in ~90% of axial SpA
IBP if 2/4 Inflammatory Back Pain: Criteria Calin et al Age <40 Duration >3 months Insidious onset Morning stiffness Improvement with exercise Sens 95% Spec 76% IBP if 4/5 Rudwaleit et al Morning stiffness >30mins Improved with exercise but not with rest Awakening in the 2 nd half of the night with pain Alternating buttock pain Sens 70.3% Spec 81.2% Expert opinion (ASAS) Age <40 Insidious onset Improvement with exercise No improvement with rest Pain at night Sens 79.6% Spec 72.4% IBP if 4/5
Screening for SpA in Chronic Back Pain Chronic Back Pain (>3 months) First symptom <45 years of age Inflammatory Back Pain If present then approx 1:5 has axial SpA Sacroiliitis on Imaging HLA-B27 +ve Approx 1:3 has axial SpA Refer to Rheumatologist Sieper, Ann Rheum Dis, 2005
Performance of Referral Guidelines Brandt, Ann Rheum Dis, 2007
Effect of 24 weeks Anti-TNF on productivity Median change in productivity score Median % change in productivity score Mean number of working days lost during study Placebo Infliximab P-value 0.72 2.2 <0.05 11% 62% <0.05 7 3 0.07 Van der Heidje, Arthritis Rheum, 2006
Effect on Work Productivity
ASAS 40 response to anti-tnf therapy No head-head comparison data available; data from phase III studies
Why Treat Ankylosing Spondylitis - Mortality Ann Rheum Dis 2011;70:1921 1925. doi:10.1136/ard.2011.151191
Response to NSAIDs 90 80 80 70 70 60 60 50 40 50 40 30 30 20 20 10 10 0 AS (n-69) Mechanical Back Pain (n-768) 0 Etoricoxib (n-195) Placebo (n-93) Van der Heidje, Arthritis Rheum, 2005 Amor, Rev Rheum Eng Ed, 1995
Management of axial SpA
Conclusions Important cause of back pain in younger adults Associated with significant morbidity, mortality and work loss Diagnosis may be expedited by awareness of inflammatory back pain Several effective treatment options are available