Background/Purpose:  

The improvement of treatment in axial Spondyloarthritis (axSpA) and the development of the ASAS classification criteria have facilitated the early diagnosis and management of this disease. It is important to know what are the more relevant predictors of radiographic progression in early SpA to take clinical decision.

 The aim of this study was to assess predictive factors for radiographic sacroiliitis progression in a cohort of early axSpA.

Methods:

Patients included in the study came from the early SpA unit at our hospital, as part of the ESPERANZA programme, a nationwide health management programme designed to provide excellence in care for early SpA. One of the inclusion criteria was symptom duration between 3 and 24 months. Every patient had a complete examination at baseline that included ESR, CRP, ASDAS-CRP, ASDAS-ESR, BASDAI, HLA-B27, radiographs of pelvis and Magnetic resonance (MRI) of sacroiliac joints (SIJ).  MRI of SIJ were assessed according to ASAS definition for bone marrow oedema. Radiographs of pelvis at baseline and at follow up were done for every patient. These x-Rays were centrally digitized and the SIJ were scored according to the grading system of the modified New York criteria (mNYc). SPSS program version 17.0 was used for Statistical analysis. Paired-sample t test was used for comparison of radiographic sacroiliitis progression.

Results:

Forty-one consecutive patients from the early axial Spondyloarhtritis cohort of the Esperanza program were analyzed, 39% of them were female. The average evolution time since onset of symptoms until baseline clinic visit was 10.9±7.1 months. All patients fulfilled ASAS criteria for axSpA and three of them had Ankylosing Spondytitis (AS) according to mNYc at baseline. The mean follow up time was 3.51 years (range: 2-5years; SD±1.03). Progression of sacroiliitis over follow up by at least one grade at one side was found in 61% (25/41). Among the 38 non radiographic axSpA patients at baseline, 5 of them (13.16%) progressed to AS according to mNYc. Statistically significant radiographic progression was observed in all the variables analyzed (see table 1).

Table 1:

	Baseline   SIJ x-Ray score (mean±SD)	Follow up SIJ x-Ray score (mean±SD)	P	n
HLA-B27   positive	0.84±0.91	1.48±1.07	<0.001	23
HLA-B27   negative	0.25±0.55	0.58±0.73	<0.01	18
BASDAI<4	0.57±0.96	1.18±1.06	<0.001	14
BASDAI≥4	0.56±0.75	1.04±1.04	<0.001	26
CRP<5	0.47±0.75	0.97±0.90	<0.001	30
CRP≥5	0.82±0.96	1.41±1.30	<0.01	11
ESR<10	0.50±0.78	1.03±0.92	<0.001	29
ESR≥10	0.71±0.91	1.21±1.28	<0.01	12
ASDAS-CRP<2.1	0.35±0.73	0.76±0.85	<0.01	17
ASDAS-CRP≥2.1	0.72±0.86	1.33±1.12	<0.001	23
ASDAS-CRP<3.5	0.53±0.82	1.00±0.94	<0.001	31
ASDAS-CRP≥3.5	0.67±0.84	1.39±1.33	<0.01	8
ASDAS-ESR<2.1	0.34±0.70	0.69±0.82	<0.01	16
ASDAS-ESR≥2.1	0.71±0.87	1.35±1.10	<0.001	24
ASDAS-ESR<3.5	0.50±0.78	0.95±0.88	<0.001	31
ASDAS-ESR≥3.5	0.78±0.94	1.55±1.42	<0.01	9
MRI   positive	1.11±0.92	1.58±0.99	<0.001	14
MRI   negative	0.17±0.38	0.67±0.73	<0.001	20

Conclusion:

Every patient of this early axSpA cohort had radiographic sacroiliitis progression independently of the outcome assessed. Patients HLA-B27 positive, with MRI positive, higher values of CRP or ESR and higher scores of BASDAI and ASDAS not only presented higher  radiographic scores at baseline and but also more radiographic progression at follow up.

---

« Back to 2013 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/radiographic-sacroiliitis-progression-in-an-early-spondyloarthritis-cohort/