Deep Learning Algorithm of the SPARCC Scoring System in SI Joint MRI.

BACKGROUND: The Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system is a sacroiliitis grading system. PURPOSE: To develop a deep learning-based pipeline for grading sacroiliitis using the SPARCC scoring system. STUDY TYPE: Prospective. POPULATION: The study included 389 participants (42.2-year-old, 44.6% female, 317/35/37 for training/validation/testing). A pretrained algorithm was used to differentiate image with/without sacroiliitis. FIELD STRENGTH/SEQUENCE: 3-T, short tau inversion recovery (STIR) sequence, fast spine echo. ASSESSMENT: The regions of interest as ground truth for models' training were identified by a rheumatologist (HYC, 10-year-experience) and a radiologist (KHL, 6-year-experience) using the Assessment of Spondyloarthritis International Society definition of MRI sacroiliitis independently. Another radiologist (YYL, 4.5-year-experience) solved the discrepancies. The bone marrow edema (BME) and sacroiliac region models were for segmentation. Frangi-filter detected vessels used as intense reference. Deep learning pipeline scored using SPARCC scoring system evaluating presence and features of BMEs. A rheumatologist (SCWC, 6-year-experience) and a radiologist (VWHL, 14-year-experience) scored using the SPARCC scoring system once. The radiologist (YYL) scored twice with 5-day interval. STATISTICAL TESTS: Independent samples t-tests and Chi-squared tests were used. Interobserver and intraobserver reliability by intraclass correlation coefficient (ICC) and Pearson coefficient evaluated consistency between readers and the deep learning pipeline. We evaluated the performance using sensitivity, accuracy, positive predictive value, and Dice coefficient. A P-value <0.05 was considered statistically significant. RESULTS: The ICC and the Pearson coefficient between the SPARCC scores from three readers and the deep learning pipeline were 0.83 and 0.86, respectively. The sensitivity in identifying BME and accuracy of identifying SI joints and blood vessels was 0.83, 0.90, and 0.88, respectively. The dice coefficients were 0.82 (sacrum) and 0.80 (ilium). DATA CONCLUSION: The high consistency with human readers indicated that deep learning pipeline may provide a SPARCC-informed deep learning approach for scoring of STIR images in spondyloarthritis. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.

A deep neural network for MRI spinal inflammation in axial spondyloarthritis.

OBJECTIVE: To develop a deep neural network for the detection of inflammatory spine in short tau inversion recovery (STIR) sequence of magnetic resonance imaging (MRI) on patients with axial spondyloarthritis (axSpA). METHODS: A total 330 patients with axSpA were recruited. STIR MRI of the whole spine and clinical data were obtained. Regions of interests (ROIs) were drawn outlining the active inflammatory lesion consisting of bone marrow edema (BME). Spinal inflammation was defined by the presence of an active inflammatory lesion on the STIR sequence. The 'fake-color' images were constructed. Images from 270 and 60 patients were randomly separated into the training/validation and testing sets, respectively. Deep neural network was developed using attention UNet. The neural network performance was compared to the image interpretation by a radiologist blinded to the ground truth. RESULTS: Active inflammatory lesions were identified in 2891 MR images and were absent in 14,590 MR images. The sensitivity and specificity of the derived deep neural network were 0.80 ± 0.03 and 0.88 ± 0.02, respectively. The Dice coefficient of the true positive lesions was 0.55 ± 0.02. The area under the curve of the receiver operating characteristic (AUC-ROC) curve of the deep neural network was 0.87 ± 0.02. The performance of the developed deep neural network was comparable to the interpretation of a radiologist with similar sensitivity and specificity. CONCLUSION: The developed deep neural network showed similar sensitivity and specificity to a radiologist with four years of experience. The results indicated that the network can provide a reliable and straightforward way of interpreting spinal MRI. The use of this deep neural network has the potential to expand the use of spinal MRI in managing axSpA.

Deep learning algorithms for magnetic resonance imaging of inflammatory sacroiliitis in axial spondyloarthritis.

OBJECTIVE: The aim of this study was to develop a deep learning algorithm for detection of active inflammatory sacroiliitis in short tau inversion recovery (STIR) sequence MRI. METHODS: A total of 326 participants with axial SpA, and 63 participants with non-specific back pain (NSBP) were recruited. STIR MRI of the SI joints was performed and clinical data were collected. Region of interests (ROIs) were drawn outlining bone marrow oedema, a reliable marker of active inflammation, which formed the ground truth masks from which 'fake-colour' images were derived. Both the original and fake-colour images were randomly allocated into either the training and validation dataset or the testing dataset. Attention U-net was used for the development of deep learning algorithms. As a comparison, an independent radiologist and rheumatologist, blinded to the ground truth masks, were tasked with identifying bone marrow oedema in the MRI scans. RESULTS: Inflammatory sacroiliitis was identified in 1398 MR images from 228 participants. No inflammation was found in 3944 MRI scans from 161 participants. The mean sensitivity of the algorithms derived from the original dataset and fake-colour image dataset were 0.86 (0.02) and 0.90 (0.01), respectively. The mean specificity of the algorithms derived from the original and the fake-colour image datasets were 0.92 (0.02) and 0.93 (0.01), respectively. The mean testing dice coefficients were 0.48 (0.27) for the original dataset and 0.51 (0.25) for the fake-colour image dataset. The area under the curve of the receiver operating characteristic (AUC-ROC) curve of the algorithms using the original dataset and the fake-colour image dataset were 0.92 and 0.96, respectively. The sensitivity and specificity of the algorithms were comparable with the interpretation by a radiologist, but outperformed that of the rheumatologist. CONCLUSION: An MRI deep learning algorithm was developed for detection of inflammatory sacroiliitis in axial SpA.

Malignancies in spondyloarthritis with and without concomitant psoriasis, and the effect of disease modifying anti-rheumatic drugs.

OBJECTIVES: To determine the risk of 6 types of malignancies in spondyloarthritis (SpA) with and without psoriasis (PsO) and on disease-modifying anti-rheumatic drugs (DMARDs), compared to non-specific back pain (NSBP). METHODS: Medical records were retrieved. Patients with SpA with and without PsO were identified and compared to those with NSBP. Clinical data; follow-up duration; comorbidities; dates and types of cancer diagnosed; types and duration of DMARD therapy were collected. Propensity score adjustment was used to compare the risks of malignancies between SpA, SpA with and without PsO, and NSBP. Cox regression analysis was used to determine the risk of malignancy in DMARD therapy. RESULTS: A total of 3020 patients with SpA and 2527 patients with NSBP were studied. The mean follow-up duration in patients with SpA and NSBP was 9.6 years and 13.5 years respectively. Incidence and risk of malignancies were compatible between SpA and NSBP. The incidences of various carcinomas (per 1000 patient-years) in SpA were: 1.37 for colorectal carcinoma; 0.30 for carcinoma of pancreas; 0.30 for carcinoma of stomach; and 0.91 for lymphomas. Risk of colorectal carcinoma (HR 2.46; p=0.03) and lymphomas (HR 2.86; p=0.04) was increased in SpA with concomitant PsO. DMARD therapy was not associated with increased risks of malignancies after adjustment for confounding factors. CONCLUSIONS: Risk of malignancy was increased in SpA with PsO but not in other subtypes of SpA or DMARD therapy.

Conventional and Biologic Disease-Modifying Antirheumatic Drugs Are Not Associated With Increase in or Progression of Cervical Neoplasia Among Patients With Spondyloarthritis.

OBJECTIVES: Using a centralized electronic database, we investigated the risk of cervical neoplasia (CN) and progression of cervical intraepithelial neoplasia (CIN) among patients with spondyloarthritis (SpA) receiving disease-modifying antirheumatic drugs (DMARDs). METHOD: A total of 951 patients with SpA were reviewed. Incidence and progression of CN and clinical data including age, ethnicity, smoking and drinking status, dates of first and last follow-up, history of psoriasis, inflammatory bowel disease, medications used, mean dose and duration of medications, and comorbidities were reviewed. Cox regression models were used to evaluate the individual risk of DMARDs with CN and the risk of CIN progression. RESULTS: During a mean follow-up duration of 9.2 ± 5.9 years, 34 patients had developed CN, which translates to an incidence for development of CN in patients with SpA of 3.9 per 1000 patient-years. Univariate Cox regression analyses showed no differences in clinical characteristics (psoriasis hazards ratio [HR] = 0.92, p = 0.82; inflammatory bowel disease HR = 0.05, p = 0.61; diabetes mellitus HR = 2.82, p = 0.21; chronic kidney disease HR = 0.39, p = 0.35) and medications exposure (sulfasalazine HR = 0.49, p = 0.30; methotrexate HR = 0.52, p = 0.11; leflunomide HR = 0.52, p = 0.37; adalimumab HR = 0.83, p = 0.80; certolizumab HR = 0.05, p = 0.74; etanercept HR = 0.40, p = 0.36; golimumab HR = 0.05, p = 0.32; infliximab HR = 0.05, p = 0.39; secukinumab HR = 1.00, p = 1.00; ustekinumab HR = 0.05, p = 0.78) between patients who had and had not develop CN during the study period. Progression of CIN was independently associated with higher grades of CIN lesion (HR = 6.20; p = 0.05). CONCLUSIONS: There was low risk of development and progression of CN in patients with SpA on conventional or biologic DMARD therapy.

Epidemiology, mortality and effectiveness of prophylaxis for Pneumocystis jiroveci pneumonia among rheumatic patients: a territory-wide study.

BACKGROUND: Pneumocystis jiroveci pneumonia (PJP) is an opportunistic infection affecting immunocompromised individuals. However, evidence regarding the burden and effectiveness of prophylaxis among rheumatic patients remains limited. Delineating the epidemiology and efficacy of prophylaxis among rheumatic patients is urgently needed. METHODS: We performed a territory-wide cohort study of rheumatic patients in Hong Kong. All patients with a diagnosis of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV), immune-mediated myositis (IMM), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), or spondyloarthritis (SpA) between 2015 and 2019 were included. Prevalence, frequency of prophylaxis and mortality of PJP were calculated. Number needed to treat (NNT) analysis was also performed. RESULTS: Out of 21,587 patients (54% RA, 25% SLE, 13% SpA, 5% IMM, 2% AAV and 1% SSc), 1141 (5.3%) patients were prescribed PJP prophylaxis. 48/21,587 (0.2%) developed PJP. No patients who developed PJP received prophylaxis prior to infection. The incidence of PJP was highest among SSc, AAV, and IMM patients. Among these diseases, the majority of PJP occurred while patients were on glucocorticoids at daily prednisolone-equivalent doses of 15 mg/day (P15) or above. PJP prophylaxis was effective with NNT for SSc, AAV and IIM being 36, 48 and 114 respectively. There were 19 PJP-related mortalities and the mortality rate was 39.6%. CONCLUSION: PJP is an uncommon but important infection among rheumatic patients, PJP prophylaxis is effective and should be considered in patients with SSc, AAV and IMM, especially those receiving glucocorticoid doses above P15.

Responsiveness of the EuroQoL 5-Dimension (EQ-5D) questionnaire in patients with spondyloarthritis.

BACKGROUND: Spondyloarthritis (SpA) has a significant impact on patients' quality of life due to functional impairments. Generic health instruments like the EuroQoL 5-dimension (EQ-5D) is important for cost-utility analysis of health care interventions and calculation of quality-adjusted life-years. It has been validated in patients with SpA. However, its responsiveness property is unclear. Hence, the aim of study is to test the responsiveness properties of the EQ-5D health measure for Chinese patients with SpA. METHODS: Prospective and consecutive recruitment of 151 Chinese patients with SpA was conducted with follow-up assessments 6 months later. Demographic data including smoking and drinking habits, education level, income and occupation was collected. Disease-associated data including disease duration, presence of back pain, peripheral arthritis, dactylitis, enthesitis, uveitis, psoriasis, and inflammatory bowel disease was also recorded. Questionnaires regarding disease activity and functional disability (BASDAI, BASFI, BASGI, BASMI, ASDAS), mental health (HADS) and the EQ-5D scores were recorded. Responsiveness was tested against the global rating of change scale (GRC) and changes in disease activity using BASDAI and ASDAS-CRP. RESULTS: A total of 113 (74.8%) patients completed the follow-up assessments. Most patients (61.6%) had low disease activity level with BASDAI <4 and 39.7% of patients had inactive disease by ASDAS-CRP. EQ-5D scores was well discriminated along with BASDAI and BASFI scores. EQ-5D scores also correlated well with HADS. The GRC was not able to discriminate adequately. No significant ceiling or floor effect was observed. CONCLUSIONS: EQ-5D demonstrates satisfactory responsiveness property for assessment of changes in SpA disease activity. LEVEL OF EVIDENCE: II.

MRI inflammation of facet and costovertebral joints is associated with restricted spinal mobility and worsened functional status.

OBJECTIVE: To investigate the association of spinal inflammation on MRI in patients with various clinical, functional and radiological outcomes in patients with axial spondyloarthritis (SpA). METHODS: Three hundred and ninety-seven participants with axial SpA and back pain were recruited from 10 rheumatology centres. Clinical, biochemical and radiological parameters were collected and participants underwent MRI of the spine. MRI features including inflammatory lesions of facet joints and costovertebral joints, corner inflammatory lesions, and spondylitis were assessed. BASFI, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Global Index, BASMI and modified Stoke Ankylosing Spondylitis Spinal Score were measured. Multivariate linear regression models were used to determine the associations between MRI parameters and various clinical, functional and radiological outcomes. RESULTS: BASMI and BASFI correlated well with inflammatory features in spinal MRI. Multivariate analysis showed that lumbar facet joint inflammation was independently associated with BASMI (regression coefficient (ß) = 0.12, P < 0.001), lumbar spinal flexion (ß = 0.13, P = 0.00), lateral spinal flexion (ß = 0.09, P = 0.04), tragus-to-wall distance (ß = 0.16, P < 0.001) and BASFI (ß = 0.14, P = 0.01). Costovertebral joint inflammation was also associated with BASMI (ß = 0.08, P = 0.05). CONCLUSION: Inflammatory lesions of facet and costovertebral joints in MRI are associated with restriction in spinal mobility and functional impairment. These important yet commonly overlooked lesions should be reviewed in clinical practice in patients with SpA.

A retrospective study on the risk of tuberculosis in patients with rheumatoid arthritis.

Tuberculosis (TB) is an important preventable infection in patients with rheumatoid arthritis (RA). To determine the risk of TB in patients with RA by comparing with those with non-specific back pain (NSBP), and to identify the risk factors in the RA group. Medical data were retrieved from a centralized electronic database. A total of 1099 patients with RA and 2489 patients with NSBP were identified. Clinical data, comorbidities, and use of individual disease-modifying anti-rheumatic drugs (DMARDs) were retrieved. Risks of TB in patients with RA and NSBP were compared by propensity score (PS) adjusted analysis with known or potential risk factors for TB. Risk factors of TB were also determined in patients with RA. There were 14 cases of TB in RA group and 25 cases in NSBP group. Median duration of follow-up were 11.3 (0.1-21.9) years in RA group and 15.4 (0.1-24.4) years in NSBP group. The risk of TB in patients with RA was 2.53 times higher (HR 2.53; 95% CI 1.29, 4.94; p < 0.01) than in patients with NSBP. After excluding patients on DMARDs, the risk became similar (HR 2.72; 95% CI 0.81, 9.14; p = 0.11). Independent risk factors found were etanercept (HR 7.16; 95% CI 1.41, 36.30; p = 0.02), and previous TB infection (HR 25.23; 95% CI 6.99, 91.09; p < 0.001). The risk of extrapulmonary involvement between RA and NSBP groups was similar (HR 1.21; 95% CI 0.22, 6.57; p = 0.83). The risk of TB was increased in patients with RA. Anti-TNF therapy was an identified risk factor.

Risk of tuberculosis in patients with spondyloarthritis: data from a centralized electronic database in Hong Kong.

BACKGROUND/ OBJECTIVE: Tuberculosis (TB) is one of the most infectious comorbidities in spondyloarthritis (SpA). Our goals were to determine the crude incidence rate of and risk factors for TB in SpA. METHOD: Clinical data of 2984 patients with SpA from 11 rheumatology centres were reviewed. This included demographics, duration of follow-up, comorbidities including diabetes, chronic kidney disease, chronic heart disease, chronic lung disease, stroke and malignancies, date of diagnosis of tuberculosis, use of non-steroidal anti-inflammatory drugs, duration of glucocorticoid therapy for more than 6 months, conventional (cDMARD) and biological (bDMARD) disease modifying anti-rheumatic drug therapies. Crude incidence rates were reported. Cox regression models were used to determine the risk factors for TB in patients with SpA. RESULTS: Forty-three patients had TB, of which 4 (9.3%) were extra-pulmonary. The crude incidence rate of TB was 1.57 in patients with SpA, compared with 0.58 in the general population in Hong Kong. Independent risk factors identified from the multivariate Cox regression model were: alcohol use (HR 2.62; p = 0.03), previous TB (HR 13.62; p < 0.001), chronic lung disease (HR 3.39; p = 0.004), duration of glucocorticoid therapy greater than 6 months (HR 3.25; p = 0.01) and infliximab therapy (HR 5.06; p < 0.001). Age was associated with decreased risk (HR 0.93; p < 0.001). CONCLUSION: Incidence of TB was higher in patients with SpA. Glucocorticoid therapy beyond 6 months and infliximab therapy increased the risk of TB. Rheumatologists should avoid prolonged use of glucocorticoids and consider DMARDs other than infliximab in the treatment of at-risk patients.

Clinical Associations of Uveitis in Axial Spondyloarthritis Group and Ankylosing Spondylitis Group: Do They Represent the Same Disease?

OBJECTIVE: The aim of this study was to determine the prevalence and associated factors for uveitis in ethnic Chinese patients with axial spondyloarthritis (SpA) and ankylosing spondylitis (AS). METHODS: This was a cross-sectional study. Patients fulfilling the Assessment of SpondyloArthritis international Society axial SpA criteria were recruited consecutively from 3 rheumatology centers in Hong Kong from March 2014 to July 2017. Clinical and biochemical parameters were collected. History of uveitis was inquired from both history and medical records. All patients received lumbosacral spine x-rays and whole-spine and sacroiliac joint magnetic resonance imaging. Patients were defined as axial SpA if they fulfilled the Assessment of SpondyloArthritis international Society criteria and AS if they fulfilled the modified New York criteria. Clinical and radiological findings were compared between patients with and without uveitis in the 2 groups. Factors associated with uveitis were identified with univariate analyses and multivariate logistic regression analyses. RESULTS: Among 252 patients, 67 patients (26.6%) had a history of uveitis. The male-to-female ratio was 55.4 to 44.6. Disease duration was 12.3 ± 11.7 years. In the axial SpA group, multivariate regression showed that older age (odds ratio [OR], 1.05; p = 0.01), human leukocyte antigen B27 positivity (OR, 11.79; p = 0.01), and history of inflammatory bowel disease (OR, 9.74; p = 0.04) were positively associated with uveitis. In the AS group, multivariate regression showed that back pain duration (OR, 1.05; p = 0.01) and male sex (OR, 3.46; p = 0.03) were associated with uveitis. CONCLUSIONS: Axial SpA represents a spectrum of diseases. Its clinical associations with uveitis should be distinguished from those of traditional AS.

Apparent Diffusion Coefficient as an Imaging Biomarker for Spinal Disease Activity in Axial Spondyloarthritis.

Background A quantifiable imaging measure to gauge the intensity of individual inflammatory lesions in axial spondyloarthritis (SpA) has not been well established. Previous studies have shown that diffusion-weighted (DW) MRI reflects disease activity in axial SpA. Purpose To determine the association between apparent diffusion coefficient (ADC) at MRI of discovertebral lesions and disease activity in individuals with axial SpA. Materials and Methods In this prospective study, 243 study participants (mean age ± standard deviation, 43.2 years ± 13.5) with back pain who fulfilled the Assessment of SpondyloArthritis International Society criteria for SpA were recruited from four rheumatology centers between April 2014 and March 2018. There were 132 men (mean age, 41.4 years ± 13.3) and 111 women (mean age, 45.3 years ± 13.4). Clinical, biochemical, and radiologic parameters were collected. All participants underwent whole-spine MRI by using a short inversion time inversion-recovery sequence and DW imaging. Two independent readers identified the presence of discovertebral lesions. ADCs were measured and normalized with normal bone marrow. Regression analysis was performed to determine association between the mean, maximum, and normalized mean and maximum ADCs of the discovertebral lesions and disease activity and functional parameters (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI], Bath Ankylosing Spondylitis Functional Index [BASFI], and Bath Ankylosing Spondylitis Global Index [BASGI]). Results Ninety-one discovertebral lesions (five cervical, 61 thoracic, 25 lumbar) were present in 55 of the 243 study participants (22.6%). After adjusting for confounding factors, increased maximum ADC was independently associated with increased BASFI (regression coefficient [ß] = 1.94 [×10-3 mm2/sec], P = .04). Increased normalized maximum ADC was independently associated with BASDAI question 2 (ie, back pain score) (ß = 0.45, P = .01), mean stiffness score (ß = 0.41, P = .04), and BASGI (ß = 0.43, P = .04). Increased normalized mean ADC was independently associated with BASDAI question 2 (ß = 0.61, P = .04). Conclusion Apparent diffusion coefficients at MRI of discovertebral lesions were associated with disease activity, functional impairment, and patient global assessment in axial spondyloarthritis. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Guermazi and Roemer in this issue.

pH-Responsive Oxygen Nanobubbles for Spontaneous Oxygen Delivery in Hypoxic Tumors.

Tumor hypoxia is a significant factor leading to the resistance of tumors to treatment, especially for photodynamic therapy and radiotherapy where oxygen is needed to kill cancer cells. Oxygen delivery agents such as oxygen-saturated perfluorocarbon nanoemulsions and lipid oxygen microbubbles have been employed to supply oxygen to hypoxic tumors with ultrasound activation. Such oxygen delivery systems are still associated with several drawbacks, including premature oxygen release and the dependence of external stimuli. To address these limitations, we developed oxygen nanobubbles that were enclosed by the acetalated dextran polymer shells for spontaneous oxygeneration in response to a minor pH drop in the tumor microenvironment. The acetalated dextran polymer shell serves as a robust barrier against gas dissolution in the circulating blood to retain the majority of the oxygen payload, and its pH-responsive property enables an abrupt burst release of oxygen in the mild acidic tumor microenvironment. The acetalated dextran oxygen nanobubbles exhibited excellent stability and biocompatibility. In vitro and in vivo experiments were conducted to investigate the pH-responsive oxygen release. The external stimuli-free supply of oxygen by the acetalated dextran oxygen nanobubbles was evaluated on CNE2 tumor-bearing mice, and the intratumoral oxygen level increased by 6-fold after the administration of the oxygen nanobubbles, manifesting that our pH-responsive oxygen nanobubbles hold great potential as a potent oxygen delivery agent to overcome the hypoxia-induced resistance.

Osteogenic circulating endothelial progenitor cells are linked to electrocardiographic conduction abnormalities in rheumatic patients.

BACKGROUND: Osteogenic circulating endothelial progenitor cells (EPC) play a pathogenic role in cardiovascular system degeneration through promulgating vasculature calcification, but its role in conduction disorders as part of the cardiovascular degenerative continuum remained unknown. AIM: To investigate the role of osteocalcin (OCN)-expressing circulating EPCs in cardiac conduction disorders in the unique clinical sample of rheumatoid arthritis (RA) susceptible to both abnormal bone metabolism and cardiac conduction disorders. METHODS: We performed flow cytometry studies in 134 consecutive asymptomatic patients with rheumatoid arthritis to derive osteogenic circulating OCN-positive (OCN+) CD34+KDR+ vs. CD34+CD133+KDR+ conventional EPC. Study endpoint was the prespecified combined endpoint of electrocardiographic conduction abnormalities. RESULTS: Total prevalence of cardiac conduction abnormality was 9% (n = 12). All patients except one had normal sinus rhythm. One patient had atrial fibrillation. No patient had advanced atrioventricular (AV) block. Prevalence of first-degree heart block (>200 ms), widened QRS duration (>120 ms) and right bundle branch block were 6.7%, 2.1%, and 2.2% respectively. Circulating osteogenic OCN+ CD34+ KDR+ EPCs were significantly higher among patients with cardiac conduction abnormalities (p = 0.039). Elevated OCN+ CD34+ KDR+ EPCs> 75th percentile was associated with higher prevalence of cardiac conduction abnormalities (58.3% vs. 20.02%, p = 0.003). Adjusted for potential confounders, elevated OCN+ CD34+ KDR+ EPCs> 75th percentile remained independently associated with increased risk of cardiac conduction abnormalities (OR = 4.4 [95%CI 1.2-16.4], p = 0.028). No significant relation was found between conventional EPCs CD34+CD133+KDR+ and conduction abnormalities (p = 0.36). CONCLUSIONS: Elevated osteogenic OCN+ CD34+ KDR+ EPCs are independently associated with the presence of electrocardiographic conduction abnormalities in patients with rheumatoid arthritis, unveiling a potential novel pathophysiological mechanism.

Comparing diffusion weighted imaging with clinical and blood parameters, and with short tau inversion recovery sequence in detecting spinal and sacroiliac joint inflammation in axial spondyloarthritis.

OBJECTIVES: To investigate the usefulness of diffusion weighted imaging (DWI) by comparing with clinical features, blood parameters and traditional short tau inversion recovery (STIR) sequence in detecting spinal and sacroiliac (SI) joint inflammation in axial spondyloarthritis (axSpA) patients. METHODS: One hundred and ten axSpA patients were recruited. Clinical, radiological and blood parameters were recorded. DWI and STIR MRI were performed simultaneously and results were scored according to the Spondyloarthritis Research Consortium of Canada (SPARCC) for comparison. Apparent diffusion coef cient (ADC) values were also calculated. RESULTS: DWI did not correlate with clinical parameters or blood parameters. It also had lowered sensitivity. When compared with STIR sequence, it correlated well with STIR sequence at the SI joint level (CC 0.76, p<0.001), but weakly at the spinal level (CC 0.23, p=0.02). At the SI joint level, the presence of inflammation on both STIR sequence and DWI was associated with an increase in maximum (B=0.24, p=0.02 in STIR; B=0.37, p<0.001 in DWI) and mean ADC values (B=0.17, p=0.003 in STIR; B=0.15, p=0.01 in DWI). Maximum (B=0.19, p=0.04) and mean spinal ADC values (B=0.18, p=0.01) were also positively associated with DWI detected spinal inflammation. Presence of Modic lesions showed positive correlation with STIR sequence (B=7.12, p=0.01) but not spinal ADC values. CONCLUSIONS: Despite DWI correlates with STIR sequence, it has lower sensitivity. However, ADC values appear to be independent of Modic lesions and may supplement STIR sequence to differentiate degeneration.

The Discriminative Values of the Bath Ankylosing Spondylitis Disease Activity Index, Ankylosing Spondylitis Disease Activity Score, C-Reactive Protein, and Erythrocyte Sedimentation Rate in Spondyloarthritis-Related Axial Arthritis.

OBJECTIVES: The aims of this study were to determine the effectiveness of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score-C-Reactive Protein (ASDAS-CRP), Ankylosing Spondylitis Disease Activity Score-Erythrocyte Sedimentation Rate (ASDAS-ESR), and inflammatory markers in screening for axial-joint inflammation as detected by magnetic resonance imaging (MRI) and to find out factors that could affect scoring of the indices. METHODS: One hundred fifty-three Chinese spondyloarthritis patients were recruited. Clinical data and BASDAI were collected, and Bath Ankylosing Spondylitis Metrology Index was measured. Serum ESR and CRP were checked, and ASDAS-ESR and ASDAS-CRP were calculated. Radiographs of cervical and lumbar spine were performed for modified Stoke Ankylosing Spondylitis Spinal Score. All patients underwent MRI of the spine and sacroiliac joints. Axial-joint inflammation was evaluated by Spondyloarthritis Research Consortium of Canada MRI indices. Multivariate linear regressions were used to determine potential factors that could affect disease activity indices. Receiver operating characteristic curve was used to determine the effectiveness in screening for axial-joint inflammation. RESULTS: BASDAI was associated with current back pain (B = 0.89, P = 0.01), ASDAS-CRP with current back pain (B = 0.74, P = 0.04), and current dactylitis (B = 0.70, P = 0.03) ASDAS-ESR with current back pain (B = 0.95, P = 0.01), and current dactylitis (B = 0.99, 0.002). The ROC curve revealed that CRP was the only variable that successfully discriminated spondyloarthritis patients with and without axial-joint inflammation by MRI, although it had poor accuracy (area under the curve, 0.63; 95% confident interval, 0.53-0.72; P = 0.01). CONCLUSIONS: Based on our results, MRI could be used to supplement traditional disease assessment tools for more accurate disease evaluation.

Left ventricular myocardial dysfunction and premature atherosclerosis in patients with axial spondyloarthritis.

OBJECTIVE: To evaluate left ventricular (LV) function and carotid intima-media thickness (IMT) in patients with axial SpA in relationship to underlying disease severity. METHODS: We recruited 104 patients with axial SpA and 50 controls. Detailed transthoracic echocardiography was performed and analysed with two-dimensional speckle tracking strain analysis for systolic function and tissue Doppler-derived E/E' for diastolic function assessment. Carotid IMT was measured by ultrasonography to evaluate subclinical atherosclerosis. Radiological severity of patients with axial SpA was assessed by the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). RESULTS: Despite a similar LV ejection fraction [62.7% (s.d. 3.9) vs 62.8% (s.d. 3.8), P = 0.83], patients with axial SpA had impaired LV myocardial longitudinal strain (LS), circumferential strain (CS) and radial strain (RS) compared with controls [-18.1% (s.d. 2.4) vs -20.1% (s.d. 2.5), -17.2% (s.d. 2.2) vs -20.3% (s.d. 2.9) and 37.1% (s.d. 8.6) vs 43.2% (s.d. 10.9), respectively; all P < 0.01]. In addition, patients with axial SpA had a greater E/E' [7.9 (s.d. 2.5) vs 7.0 (s.d. 1.7), P < 0.01] and carotid IMT [0.78 mm (s.d. 0.19) vs 0.69 mm (s.d. 0.10), P < 0.01] than controls. After adjusting for potential confounding factors, axial SpA remained independently associated with LV myocardial strains, E/E' and carotid IMT. Importantly, multivariate linear regression analysis demonstrated that mSASSS was independently associated with LV longitudinal strain, E/E' and carotid IMT. CONCLUSION: Our study demonstrated that patients with axial SpA had impaired LV systolic and diastolic function and increased carotid IMT. Importantly, mSASSS was independently associated with LV longitudinal strain, E/E' and carotid IMT after adjusting for confounding factors. Speckle tracking echocardiography may be a useful tool for early detection of impaired LV function in patients with SpA and carotid IMT examination can provide valuable assessment of subclinical atherosclerosis in patients with SpA.