Polygenic Risk Scores have high diagnostic capacity in ankylosing spondylitis.

Objective: We sought to test the hypothesis that Polygenic Risk Scores (PRSs) have strong capacity to discriminate cases of ankylosing spondylitis (AS) from healthy controls and individuals in the community with chronic back pain.

Methods: PRSs were developed and validated in individuals of European and East Asian ethnicity, using data from genome-wide association studies in 15 585 AS cases and 20 452 controls. The discriminatory values of PRSs in these populations were compared with other widely used diagnostic tests, including C-reactive protein (CRP), and sacroiliac MRI.

Chronic back pain in first-degree relatives (FDRs) of patients with ankylosing spondylitis: predictive value of HLA-B27 and persistence of inflammatory back pain over time.

Background/purpose: First-degree relatives (FDRs) of patients with ankylosing spondylitis (AS) may be at high risk of spondyloarthritis. We examined the frequency, characteristics of chronic back pain (CBP), associated features, persistence of symptoms, and HLA-B27 allele frequency in FDRs of AS patients, also comparing those FDRs with participants in NHANES 2009-2010 with CBP.

Methods: 399 FDRs of AS probands were divided into: (1) No CBP (subjects >40 years old at study visit without CBP) (n=162); (2) NICBP (non-inflammatory CBP) (n=82), and (3) CIBP (inflammatory CBP) (n=155).

The changing profile of ankylosing spondylitis in the biologic era.

Objective: To compare disease characteristics, comorbidities, and medication utilization of 1141 patients with ankylosing spondylitis (AS) with short (< 20 years) and long (≥ 20 years) disease duration enrolled in the Prospective Study of Outcomes in AS (PSOAS) study over three different periods of time and followed longitudinally.

Methods: Study visits were carried out every 6 months examining disease activity (Bath AS Disease Activity Index (BASDAI), C-reactive protein, erythrocyte sedimentation rate), functional impairment, depression, and medication utilization as well as radiographic severity. Groups were compared with regression models using generalized estimating equation, linear, and Poisson regressions after adjusting for sites and for patients withdrawing from the study at less than 2 years follow-up.

Harmonization, data management, and statistical issues related to prospective multicenter studies in Ankylosing spondylitis (AS): Experience from the Prospective Study Of Ankylosing Spondylitis (PSOAS) cohort.

Ankylosing spondylitis (AS) is characterized by inflammation of the spine and sacroiliac joints causing pain and stiffness and, in some patients, ultimately new bone formation, and progressive joint ankyloses. The classical definition of AS is based on the modified New York (mNY) criteria. Limited data have been reported regarding data quality assurance procedure for multicenter or multisite prospective cohort of patients with AS.

A multiple imputation method based on weighted quantile regression models for longitudinal censored biomarker data with missing values at early visits.

Background: In patient-based studies, biomarker data are often subject to left censoring due to the detection limits, or to incomplete sample or data collection. In the context of longitudinal regression analysis, inappropriate handling of these issues could lead to biased parameter estimates. We developed a specific multiple imputation (MI) strategy based on weighted censored quantile regression (CQR) that not only accounts for censoring, but also missing data at early visits when longitudinal biomarker data are modeled as a covariate.

Opioid Analgesic Use in Patients with Ankylosing Spondylitis: An Analysis of the Prospective Study of Outcomes in an Ankylosing Spondylitis Cohort.

Objective: Opioid analgesics may be prescribed to ankylosing spondylitis (AS) patients with pain that is unresponsive to antirheumatic treatment. Our study assessed factors associated with opioid usage in AS.

Methods: A prospective cohort of 706 patients with AS meeting modified New York criteria followed at least 2 years underwent comprehensive clinical evaluation of disease activity and functional impairment.

Ethnicity and disease severity in ankylosing spondylitis a cross-sectional analysis of three ethnic groups.

The purpose of this study is to compare disease severity in ankylosing spondylitis (AS) in three ethnic groups. We assessed 925 AS patients (57 Blacks, 805 Whites, 63 Latinos) enrolled in the longitudinal Prospective Study of Outcomes in AS (PSOAS) for functional impairment, disease activity, and radiographic severity. Comparisons of clinical characteristics and HLA-B27 frequency for each group were performed, in two multivariable regression models, we compared the baseline Bath Ankylosing Spondylitis Radiographic Index (BASRI) and modified Stokes Ankylosing Spondylitis Spine Score (mSASSS) by ethnicity, adjusting for covariates.

New population-based reference values for spinal mobility measures based on the 2009-2010 National Health and Nutrition Examination Survey.

Objective: To report population-based percentile reference values for selected spinal mobility measures in a nationally representative sample of 5,001 US adults ages 20-69 years who were examined in the 2009-2010 US National Health and Nutrition Examination Survey (NHANES).

Methods: Occiput-to-wall distance (OWD), thoracic expansion (TE), and anterior lumbar flexion (ALF; by modified Schober test) were measured by trained examiners in a standardized manner. TE was measured at the xiphisternal level, while the lower reference point for ALF was a line marked at the level of the superior margin of the lateral iliac crests.

Psychological correlates of self-reported disease activity in ankylosing spondylitis.

Objective: To investigate the role of psychological variables in self-reported disease activity in patients with ankylosing spondylitis (AS), while controlling for demographic and medical variables.

Methods: Patients with AS (n = 294) meeting modified New York criteria completed psychological measures evaluating depression, resilience, active and passive coping, internality, and helplessness. Demographic, clinical, and radiologic data were also collected.

Genome-wide association study of ankylosing spondylitis identifies non-MHC susceptibility loci.

To identify susceptibility loci for ankylosing spondylitis, we undertook a genome-wide association study in 2,053 unrelated ankylosing spondylitis cases among people of European descent and 5,140 ethnically matched controls, with replication in an independent cohort of 898 ankylosing spondylitis cases and 1,518 controls. Cases were genotyped with Illumina HumHap370 genotyping chips. In addition to strong association with the major histocompatibility complex (MHC; P < 10(-800)), we found association with SNPs in two gene deserts at 2p15 (rs10865331; combined P = 1.

Psychological correlates of self-reported functional limitation in patients with ankylosing spondylitis.

Introduction: Functional status is an integral component of health-related quality of life in patients with ankylosing spondylitis (AS). The purpose of this study was to investigate the role of psychological variables in self-reported functional limitation in patients with AS, while controlling for demographic and medical variables.

Methods: 294 AS patients meeting modified New York Criteria completed psychological measures evaluating depression, resilience, active and passive coping, internality and helplessness at the baseline visit.

Plasma cytokine profiles in systemic sclerosis: associations with autoantibody subsets and clinical manifestations.

Introduction: Systemic sclerosis (SSc) (scleroderma) is a complex autoimmune disease that clinically manifests as progressive fibrosis of the skin and internal organs. Anti-centromere antibodies (ACAs), anti-topoisomerase antibodies (ATAs), and anti-RNA polymerase III antibodies (ARAs) are three mutually exclusive SSc-associated autoantibodies that correlate with distinct clinical subsets characterized by extent of cutaneous involvement and pattern of organ involvement. The current report sought to determine whether plasma cytokine profiles differ in SSc patients grouped according to these SSc-associated autoantibody subsets.

Efficacy and safety of golimumab in patients with ankylosing spondylitis: results of a randomized, double-blind, placebo-controlled, phase III trial.

Objective: To evaluate the efficacy and safety of golimumab in patients with ankylosing spondylitis (AS) in the GO-RAISE study.

Methods: Patients with active AS, a Bath AS Disease Activity Index (BASDAI) score > or =4, and a back pain score of > or =4 were randomly assigned in a 1.8:1.