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2.
J Biopharm Stat ; : 1-18, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730441

RESUMO

Evaluating the association between diseases and the longitudinal pattern of pharmacological therapy has become increasingly important. However, in many longitudinal studies, self-reported medication usage data collected at patients' follow-up visits could be missing for various reasons. These pieces of missing or inaccurate/untenable information complicate determining the trajectory of medication use and its complete effects for patients. Although longitudinal models can deal with specific types of missing data, inappropriate handling of this issue can lead to a biased estimation of regression parameters especially when missing data mechanisms are complex and depend upon multiple sources of variation. We propose a latent class-based multiple imputation (MI) approach using a Bayesian quantile regression (BQR) that incorporates cluster of unobserved heterogeneity for medication usage data with intermittent missing values. Findings from our simulation study indicate that the proposed method performs better than traditional MI methods under certain scenarios of data distribution. We also demonstrate applications of the proposed method to data from the Prospective Study of Outcomes in Ankylosing Spondylitis (AS) cohort when assessing an association between longitudinal nonsteroidal anti-inflammatory drugs (NSAIDs) usage and radiographic damage in AS, while the longitudinal NSAID index data are intermittently missing.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31529687

RESUMO

OBJECTIVE: Nonsteroidal anti-inflammatory drugs (NSAIDs) increase blood pressure and potentially cardiovascular burden, which may limit their use in ankylosing spondylitis (AS). Our objective was to determine the association of NSAID use with incident hypertension in a longitudinal AS cohort. METHODS: Adults with AS were enrolled in a prospective cohort study of patient outcomes and examined every 4-6 months. Hypertension was defined by patient-reported hypertension; anti-hypertensive medication use; or, on two consecutive visits, systolic blood pressure ≥140 mm Hg or diastolic ≥90 mm Hg. Continuous NSAID use was dichotomized based on the validated NSAID index. We assessed the association of NSAID use as a time-varying exposure with the incidence of hypertension using Cox proportional hazards models. RESULTS: Of the 1282 patients in the cohort, 628 patients without baseline hypertension had at least one year of follow up, and were included in the analysis. Of these, 72% were male, the mean age at baseline was 39 ± 13 years, and 200 used NSAIDs continuously. On follow-up, 129 developed incident hypertension. After controlling for other variables, continuous NSAID use was associated with a hazard ratio (HR) of 1.12 for incident hypertension (95% CI, 1.04-1.20), compared to non-continuous or no use. The association did not differ in subgroups defined by age, body mass index, biologic use, or disease activity. CONCLUSION: In our prospective, longitudinal AS cohort, continuous NSAID use was associated with a 12% increased risk for the development of incident hypertension, as compared to non-continuous or no NSAID use.

4.
J Rheumatol ; 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371654

RESUMO

OBJECTIVE: To assess the reliability and validity of selected National Institute of Healthdeveloped Patient-Reported Outcomes Measurement Information System (PROMIS) Short Forms (SFs) in Ankylosing Spondylitis (AS) patients across Assessment in Spondyloarthritis International Society core set and patient-identified domains. METHODS: Participants the Prospective Study of Outcomes in Ankylosing Spondylitis (PSOAS), an ongoing, prospective longitudinal observational study, completed six PROMIS SFs assessing global health, depression, fatigue, physical function, pain intensity and interference during their PSOAS visits from September 2017-January 2019. Test-retest reliability and internal consistency was assessed using Intraclass correlation coefficients and Cronbach's alpha, respectively. PROMIS SFs were compared to legacy measures collected. Construct validity was evaluated through examination of score distributions, floor effects and through examination of the Spearman's correlation coefficients between PROMIS measures and existing legacy AS measures. Discriminant validity was tested across Ankylosing Spondylitis Disease Activity Score (ASDAS) groups. RESULTS: Participants (N=119) were mostly male (69%), white (81%) with a mean(SD) age of 51(±15) years. Legacy measures demonstrated floor effects that were not present in PROMIS SFs. Good test-retest reliability (r>0.8) and excellent internal consistency (>0.9) was noted in the PROMIS SFs. The six PROMIS SFs correlated moderately to strongly (rho 0.68[Depression]- 0.87[Physical Function]) with appropriate legacy measures. PROMIS scores measures worsened significantly (p<.05) with higher ASDAS groups. CONCLUSION: This study supports the reliability and construct validity of PROMIS SFs to assess AS symptoms from a single-center sample of AS patients. Further research is needed to test responsiveness, feasibility/resource burden, and different cultural/societal contexts for AS patients.

5.
Mol Med ; 25(1): 25, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31195969

RESUMO

BACKGROUND: Tumor necrosis factor (TNF) blockers have a high efficacy in treating Ankylosing Spondylitis (AS), yet up to 40% of AS patients show poor or even no response to this treatment. In this paper, we aim to build an approach to predict the response prior to clinical treatment. METHODS: AS patients during the active progression were included and treated with TNF blocker for 3 months. Patients who do not fulfill ASASAS40 were considered as poor responders. The Immunoglobulin G galactosylation (IgG-Gal) ratio representing the quantity of IgG galactosylation was calculated and candidate single nucleotide polymorphisms (SNPs) in patients treated with etanercept was obtained. Machine-learning models and cross-validation were conducted to predict responsiveness. RESULTS: Both IgG-Gal ratio at each time point and differential IgG-Gal ratios between week 0 and weeks 2, 4, 8, 12 showed significant difference between responders and poor-responders. Area under curve (AUC) of the IgG-Gal ratio prediction model was 0.8 after cross-validation, significantly higher than current clinical indexes (C-reactive protein (CRP) = 0.65, erythrocyte sedimentation rate (ESR) = 0.59). The SNP MYOM2-rs2294066 was found to be significantly associated with responsiveness of etanercept treatment. A three-stage approach consisting of baseline IgG-Gal ratio, differential IgG-Gal ratio in 2 weeks, and rs2294066 genotype demonstrated the ability to precisely predict the response of anti-TNF therapy (100% for poor-responders, 98% for responders). CONCLUSIONS: Combination of different omics can more precisely to predict the response of TNF blocker and it is potential to be applied clinically in the future.

6.
J Rheumatol ; 46(10): 1277-1283, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30824635

RESUMO

OBJECTIVE: Evaluate safety and efficacy of intravenous (IV) golimumab (GOL) in patients with active ankylosing spondylitis (AS) through 1 year. METHODS: A total of 208 patients were randomized to IV infusions of GOL 2 mg/kg (n = 105) at weeks 0, 4, and every 8 weeks thereafter or placebo (n = 103) at weeks 0, 4, and 12, then crossover to GOL at weeks 16, 20, and every 8 weeks thereafter through Week 52. Efficacy was assessed using the Assessment of Spondyloarthritis international Society (ASAS) criteria, the Ankylosing Spondylitis Disease Activity Score (ASDAS), the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and the Bath Ankylosing Spondylitis Functional Index (BASFI). Health-related quality of life was assessed using the AS Quality of Life (ASQoL) index. Efficacy and safety were monitored through Week 52 and Week 60, respectively. RESULTS: The primary endpoint (ASAS20) and all controlled endpoints at Week 16 were achieved. At Week 52, 69.5% and 65.0% of patients in the GOL group and placebo crossover group, respectively, achieved an ASAS20; 56.2% and 51.5% achieved an ASAS40; 56.2% and 55.3% achieved a BASDAI50; 24.8% and 24.3% achieved ASAS partial remission; and 25.7% and 26.2% met ASDAS inactive disease criteria (all last observation carried forward). Mean changes from baseline to Week 52 in BASFI and ASQoL scores were similar between the GOL group and the placebo crossover group (BASFI: -2.7 and -2.6; ASQoL: -5.5 and -5.4). Through Week 60, 55.4% of all GOL-treated patients had ≥ 1 adverse events (AE); 3.4% had ≥ 1 serious AE. CONCLUSION: Efficacy was maintained through 1 year with IV GOL 2 mg/kg among patients with active AS. AE were consistent with the known safety profile of GOL.

7.
J Rheumatol ; 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30709959

RESUMO

OBJECTIVE: To identify baseline features that predict progression of hand contractures and to assess the effect of contractures on functional status in the prospective GENISOS cohort. METHODS: Rate of decline in hand extension, as an indicator of hand contracture, was the primary outcome. We assessed longitudinal hand extension measurements, modified Health Assessment Questionnaire (MHAQ) score, Medical Outcomes Study Short Form-36 (SF-36) physical function score, and demographic, clinical, and serological variables. Subjects with ≥ 2 hand measurements at least 6 months apart were included. RESULTS: A total of 1087 hand measurements for 219 patients were available over an average of 8.1 ± 4.8 years. Hand extension decreased on average by 0.11 cm/year. Antitopoisomerase I antibody (ATA) positivity and higher modified Rodnan Skin Score (mRSS) were predictive of faster decline in hand extension (p = 0.009 and p = 0.046, respectively). In a subgroup analysis of 62 patients with ≤ 2 years from SSc onset, ATA and diffuse disease type were associated with faster decline in hand extension; anticentromere positivity was associated with slower rate of decline. Although the rate of decline in patients with disease duration ≤ 2 years was numerically higher, the difference was not statistically significant. Hand extension continued to decline in a linear fashion over time and was inversely related to overall functional status. CONCLUSION: ATA was predictive of contracture development in both early disease (≤ 2 yrs) and in the overall cohort. Hand extension declined linearly over time and was inversely associated with MHAQ and SF-36 scores. ATA positivity and higher baseline mRSS were predictive of faster decline in hand extension.

10.
J Rheumatol ; 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30442821

RESUMO

OBJECTIVE: Findings from previous genome-wide association studies indicated an association of the NOTCH4 gene with systemic sclerosis (SSc). This is a followup study to fine-map exonic variants of NOTCH4 in SSc. METHODS: All exons of NOTCH4 were sequenced and analyzed in a total of 1006 patients with SSc and 1004 controls of US white ancestry with the Ion Torrent system. Identified SSc-associated variants were confirmed with Sanger sequencing, and then examined in a Chinese Han cohort consisting of 576 patients with SSc and 574 controls. The NOTCH4 variants were analyzed for association with SSc as a whole and with SSc clinical and autoantibody subtypes with and without the influence of specific HLA-class II alleles that had been previously identified as major genetic factors in SSc. RESULTS: A total of 12 SSc-associated and SSc subtype-associated exonic variants of NOTCH4 were identified in the US cohort. Three of them are nonsynonymous single-nucleotide polymorphisms and 1 is a CTG tandem repeat that encodes for a poly-leucine, all of which are located in the NOTCH4 extracellular domain (NECD). Conditional logistic regression analysis on SSc-associated HLA-class II alleles indicated an independent association of the NOTCH4 variants with SSc autoantibody subtypes. Analysis of the Chinese cohort supported a genetic contribution of NOTCH4 to SSc and its subtypes. CONCLUSION: Multiple NOTCH4 exonic variants were associated with SSc and/or SSc subtypes. Several of these variants encode nonsynonymous sequence changes occurring in the NECD, which implicates a potentially functional effect of NOTCH4.

11.
Ann Rheum Dis ; 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30341055

RESUMO

OBJECTIVE: To examine associations of HLA class I and class II alleles with ankylosing spondylitis (AS) in three cohorts of patients of European, Asian and African ancestry. METHODS: HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1 and HLA-DPB1 alleles were genotyped in 1948 unrelated white and 67 African-American patients with AS from the Prospective Study of Outcomes in Ankylosing Spondylitis cohort, the North American Spondylitis Consortium and Australo-Anglo-American Spondyloarthritis Consortium, 990 white and 245 African-American Controls and HLA-B alleles in 442 Han Chinese patients with AS and 346 controls from Shanghai and Gansu, China. In addition to the case:control analyses, HLA-B*27-negative patients with AS were analysed separately, and logistic regression and 'relative predispositional effects' (RPE) analyses were carried out to control for the major effect of HLA-B*27 on disease susceptibility. RESULTS: Although numerous associations were seen between HLA alleles and AS in whites, among HLA-B*27-negative patients with AS , positive associations were seen with HLA-A*29, B*38, B*49, B*52, DRB1*11 and DPB1*03:01 and negative associations with HLA-B*07, HLA-B*57, HLA-DRB1*15:01, HLA-DQB1*02:01 and HLA -DQB1*06:02. Additional associations with HLA-B*14 and B*40 (B60) were observed via RPE analysis, which excludes the HLA-B*27 alleles. The increased frequency of HLA-B*40:01 and decreased frequency of HLA-B*07 was also seen in Han Chinese and African-Americans with AS. HLA-B*08 was decreased in whites with acute anterior uveitis. CONCLUSIONS: These data, analysing the largest number of patients with AS examined to date in three ethnic groups, confirm that other HLA class I and II alleles other than HLA-B*27 to be operative in AS predisposition.

12.
Arthritis Rheumatol ; 2018 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-30343531

RESUMO

OBJECTIVE: To investigate the efficacy and safety of ixekizumab in patients with active radiographic axial spondyloarthritis (r-axSpA) and prior inadequate response or intolerance to 1 or 2 TNF inhibitors (TNFi). METHODS: In this randomized, double-blind placebo-controlled, Phase 3 trial, adult patients with inadequate response/intolerance to 1 or 2 TNFi and an established diagnosis of axSpA and fulfilling ASAS criteria for r-axSpA with radiographic sacroiliitis defined per modified NY criteria and ≥1 SpA feature were recruited and randomized 1:1:1 to placebo or 80-mg subcutaneous ixekizumab every 2 (IXEQ2W) or 4 (IXEQ4W) weeks, with a 80-mg or 160-mg starting dose. The primary endpoint was ASAS40 response at Week 16. Secondary outcomes and safety were also assessed. RESULTS: In total, 316 patients were randomized to placebo (N=104), IXEQ2W (N=98), or IXEQ4W (N=114). At Week 16, significantly higher proportions of IXEQ2W (N=30 [30.6%]; p=0.003) or IXEQ4W (N=29 [25.4%]; p=0.017) patients achieved ASAS40 versus placebo (N=13 [12.5%]), with statistically significant differences reported as early as Week 1 with ixekizumab treatment. Statistically significant improvements in disease activity, function, quality of life, and spinal MRI inflammation were observed with 16 weeks of ixekizumab treatment versus placebo. Treatment-emergent adverse events (AE) with ixekizumab treatment were more frequent than with placebo. Serious AEs were similar across treatment arms. One death was reported (IXEQ2W). CONCLUSION: Ixekizumab treatment for 16 weeks in patients with active r-axSpA and previous inadequate response or intolerance to 1 or 2 TNFi yielded rapid and significant improvements in the signs and symptoms of r-axSpA versus placebo. This article is protected by copyright. All rights reserved.

13.
Hum Mol Genet ; 27(21): 3813-3824, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30085094

RESUMO

Genetic variation within the major histocompatibility complex (MHC) contributes substantial risk for systemic lupus erythematosus, but high gene density, extreme polymorphism and extensive linkage disequilibrium (LD) have made fine mapping challenging. To address the problem, we compared two association techniques in two ancestrally diverse populations, African Americans (AAs) and Europeans (EURs). We observed a greater number of Human Leucocyte Antigen (HLA) alleles in AA consistent with the elevated level of recombination in this population. In EUR we observed 50 different A-C-B-DRB1-DQA-DQB multilocus haplotype sequences per hundred individuals; in the AA sample, these multilocus haplotypes were twice as common compared to Europeans. We also observed a strong narrow class II signal in AA as opposed to the long-range LD observed in EUR that includes class I alleles. We performed a Bayesian model choice of the classical HLA alleles and a frequentist analysis that combined both single nucleotide polymorphisms (SNPs) and classical HLA alleles. Both analyses converged on a similar subset of risk HLA alleles: in EUR HLA- B*08:01 + B*18:01 + (DRB1*15:01 frequentist only) + DQA*01:02 + DQB*02:01 + DRB3*02 and in AA HLA-C*17:01 + B*08:01 + DRB1*15:03 + (DQA*01:02 frequentist only) + DQA*02:01 + DQA*05:01+ DQA*05:05 + DQB*03:19 + DQB*02:02. We observed two additional independent SNP associations in both populations: EUR rs146903072 and rs501480; AA rs389883 and rs114118665. The DR2 serotype was best explained by DRB1*15:03 + DQA*01:02 in AA and by DRB1*15:01 + DQA*01:02 in EUR. The DR3 serotype was best explained by DQA*05:01 in AA and by DQB*02:01 in EUR. Despite some differences in underlying HLA allele risk models in EUR and AA, SNP signals across the extended MHC showed remarkable similarity and significant concordance in direction of effect for risk-associated variants.

14.
Contemp Clin Trials Commun ; 11: 127-135, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30094388

RESUMO

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. Since 2002, 1272 qualified AS patients have been enrolled from five sites (4 US sites and 1 Australian site) in the Prospective Study Of Ankylosing Spondylitis (PSOAS). In 2012, a Data Management and Statistical Core (DMSC) was added to the PSOAS team to assist in study design, establish a systematic approach to data management and data quality, and develop and apply appropriate statistical analysis of data. With assistance from the PSOAS investigators, DMSC modified Case Report Forms and developed database in Research Electronic Data Capture (REDCap). DMSC also developed additional data quality assurance procedure to assure data quality. The error rate for various forms in PSOAS databases ranged from 0.07% for medications data to 1.1% for arthritis activity questionnaire-Global pain. Furthermore, based on data from a sub study of 48 patients with AS, we showed a strong level (90.0%) of agreement between the two readers of X-rays with respect to modified Stoke Ankylosing Spondylitis Spine Score (mSASSS). This paper not only could serve as reference for future publications from PSOAS cohort but also could serve as a basic guide to ensuring data quality for multicenter clinical studies.

15.
Hum Mol Genet ; 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29912393

RESUMO

Systemic Lupus Erythematosus (SLE or lupus) (OMIM: 152700) is a chronic autoimmune disease with debilitating inflammation that affects multiple organ systems. The STAT1-STAT4 locus is one of the first and most highly-replicated genetic loci associated with lupus risk. We performed a fine-mapping study to identify plausible causal variants within the STAT1-STAT4 locus associated with increased lupus disease risk. Using complementary frequentist and Bayesian approaches in trans-ancestral Discovery and Replication cohorts, we found one variant whose association with lupus risk is supported across ancestries in both the Discovery and Replication cohorts: rs11889341. In B cell lines from patients with lupus and healthy controls, the lupus risk allele of rs11889341 was associated with increased STAT1 expression. We demonstrated that the transcription factor HMGA1, a member of the HMG transcription factor family with an AT-hook DNA-binding domain, has enriched binding to the risk allele compared to the non-risk allele of rs11889341. We identified a genotype-dependent repressive element in the DNA within the intron of STAT4 surrounding rs11889341. Consistent with expression quantitative trait locus (eQTL) analysis, the lupus risk allele of rs11889341 decreased the activity of this putative repressor. Altogether, we present a plausible molecular mechanism for increased lupus risk at the STAT1-STAT4 locus in which the risk allele of rs11889341, the most probable causal variant, leads to elevated STAT1 expression in B cells due to decreased repressor activity mediated by increased binding of HMGA1.

16.
Clin Rheumatol ; 37(6): 1605-1616, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29589132

RESUMO

The objective of this study was to systemically and comprehensively evaluate the associations between smoking and disease outcomes in patients with ankylosing spondylitis (AS). Information on smoking, clinical features, and sociodemographic characteristics was collected by a questionnaire administered directly to the patient. Group differences were analyzed by t test or chi-square test. Logistic regression analysis was conducted with the Bath AS Disease Activity Index (BASDAI), Bath AS Functional Index (BASFI), C-reactive protein, and erythrocyte sedimentation rate as the dependent variables and different stratification of smoking duration, smoking intensity, and cumulative smoking as independent variables. In order to compare our results with previous studies, meta-analysis was performed to calculate standardized mean difference (SMD) for relationship between outcomes and smoking status. A total of 1178 AS patients were analyzed. Compared with non-smokers, the risk of having active disease (BASDAI ≥ 4) was higher in patients who smoked at least 15 years, or 15 cigarettes per day, or 15 pack-years (OR = 1.70 [1.06, 2.73], 1.75 [1.08, 2.82], and 1.97 [1.06, 3.67], respectively); and smokers had increasing risk of BASDAI ≥ 4 with increasing years of smoking, or cigarettes per day, or pack-years (p-trend = 0.010, 0.008 and 0.006, respectively). The risk of having active disease was higher in patients who smoked at least 15 cigarettes per day or 15 pack-years (OR = 1.74 [1.06, 2.84] and 2.89 [1.56, 5.35], respectively), with increasing number of cigarettes per day and pack-years. Smokers had an increased risk of BASFI ≥ 4 (p-trend = 0.040 and 0.007, respectively). By meta-analysis, current, former and ever smokers had significantly higher BASDAI (SMD = 0.34 [0.18, 0.48], 0.10 [0.01, 0.19], and 0.27 [0.20, 0.34], respectively) and BASFI (SMD = 0.35 [0.16, 0.55], 0.30 [0.22, 0.39], and 0.35 [0.21, 0.50], respectively) compared to non-smokers. Smoking is a risk factor for greater disease activity and worse functioning in AS patients.


Assuntos
Fumar/efeitos adversos , Espondilite Anquilosante , Adulto , Grupo com Ancestrais do Continente Asiático , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários , Adulto Jovem
17.
PLoS One ; 13(1): e0189498, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29293537

RESUMO

Gene-level analysis of ImmunoChip or genome-wide association studies (GWAS) data has not been previously reported for systemic sclerosis (SSc, scleroderma). The objective of this study was to analyze genetic susceptibility loci in SSc at the gene level and to determine if the detected associations were shared in African-American and White populations, using data from ImmunoChip and GWAS genotyping studies. The White sample included 1833 cases and 3466 controls (956 cases and 2741 controls from the US and 877 cases and 725 controls from Spain) and the African American sample, 291 cases and 260 controls. In both Whites and African Americans, we performed a gene-level analysis that integrates association statistics in a gene possibly harboring multiple SNPs with weak effect on disease risk, using Versatile Gene-based Association Study (VEGAS) software. The SNP-level analysis was performed using PLINK v.1.07. We identified 4 novel candidate genes (STAT1, FCGR2C, NIPSNAP3B, and SCT) significantly associated and 4 genes (SERBP1, PINX1, TMEM175 and EXOC2) suggestively associated with SSc in the gene level analysis in White patients. As an exploratory analysis we compared the results on Whites with those from African Americans. Of previously established susceptibility genes identified in Whites, only TNFAIP3 was significant at the nominal level (p = 6.13x10-3) in African Americans in the gene-level analysis of the ImmunoChip data. Among the top suggestive novel genes identified in Whites based on the ImmunoChip data, FCGR2C and PINX1 were only nominally significant in African Americans (p = 0.016 and p = 0.028, respectively), while among the top novel genes identified in the gene-level analysis in African Americans, UNC5C (p = 5.57x10-4) and CLEC16A (p = 0.0463) were also nominally significant in Whites. We also present the gene-level analysis of SSc clinical and autoantibody phenotypes among Whites. Our findings need to be validated by independent studies, particularly due to the limited sample size of African Americans.


Assuntos
Grupo com Ancestrais do Continente Africano/genética , Grupo com Ancestrais do Continente Europeu/genética , Estudo de Associação Genômica Ampla , Escleroderma Sistêmico/genética , Humanos , Polimorfismo de Nucleotídeo Único
18.
BMC Med Res Methodol ; 18(1): 8, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29325529

RESUMO

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. METHODS: We assessed through simulation studies the performances of developed imputation approach by considering various scenarios of covariance structures of longitudinal data and levels of censoring. We also illustrated the application of the proposed method to the Prospective Study of Outcomes in Ankylosing spondylitis (AS) (PSOAS) data to address the issues of censored or missing C-reactive protein (CRP) level at early visits for a group of patients. RESULTS: Our findings from simulation studies indicated that the proposed method performs better than other MI methods by having a higher relative efficiency. We also found that our approach is not sensitive to the choice of covariance structure as compared to other methods that assume normality of biomarker data. The analysis results of PSOAS data from the imputed CRP levels based on our method suggested that higher CRP is significantly associated with radiographic damage, while those from other methods did not result in a significant association. CONCLUSION: The MI based on weighted CQR offers a more valid statistical approach to evaluate a biomarker of disease in the presence of both issues with censoring and missing data in early visits.

19.
J Rheumatol ; 45(3): 341-348, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29247154

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of intravenous golimumab (GOL) in patients with active ankylosing spondylitis (AS). METHODS: In a phase III, randomized, double-blind, placebo (PBO)-controlled trial, 208 patients were randomized (1:1) to intravenous (IV) infusions of GOL 2 mg/kg (n = 105) at weeks 0, 4, 12, and every 8 weeks, or PBO (n = 103) at weeks 0, 4, and 12, with crossover to GOL at Week 16. The primary endpoint was ≥ 20% improvement from baseline in the Assessment of Spondyloarthritis International Society Criteria (ASAS20) at Week 16. Secondary endpoints included ASAS40, ≥ 50% improvement in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50), and change in the Bath Ankylosing Spondylitis Functional Index (BASFI) at Week 16. Safety was monitored through Week 28. RESULTS: Significantly greater proportions of GOL-treated patients had ASAS20 response at Week 2 (37.1% vs 19.4%; p = 0.005) and at Week 16 (73.3% vs 26.2%; p < 0.001). At Week 16, 41.0% of those receiving GOL achieved BASDAI50 compared with 14.6% of those taking PBO (p < 0.001), and the GOL group had greater mean improvement in BASFI (-2.4 vs -0.5; p < 0.001). Through Week 16, 23.3% of patients in the PBO group and 32.4% of patients in the GOL group had ≥ 1 adverse event (AE); infections being the commonest type of AE. Through Week 28, two GOL-treated patients had a serious AE. CONCLUSION: GOL 2 mg/kg administered IV at weeks 0, 4, and every 8 weeks significantly reduced the signs and symptoms of AS in adults. AE were consistent with other antitumor necrosis factor therapies, with no new safety signals (Clinicaltrials.gov: NCT02186873).

20.
J Rheumatol ; 45(2): 188-194, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29196383

RESUMO

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. These were assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI). Radiographic severity was assessed by the Bath Ankylosing Spondylitis Radiology Index and modified Stokes Ankylosing Spondylitis Scoring System. Medications taken concurrently with opioids, as well as C-reactive protein (CRP) levels and erythrocyte sedimentation rate (ESR), were determined at each study visit, performed every 6 months. Analyses were carried out at baseline, and longitudinal multivariable models were developed to identify factors independently associated with chronic and intermittent opioid usage over time. RESULTS: Factors significantly associated with opioid usage, especially chronic opioid use, included longer disease duration, smoking, lack of exercise, higher disease activity (BASDAI) and functional impairment (BASFI), depression, radiographic severity, and cardiovascular disease. Patients taking opioids were more likely to be using anxiolytic, hypnotic, antidepressant, and muscle relaxant medications. Multivariable analysis underscored the association with smoking, older age, antitumor necrosis factor agent use, and psychoactive drugs, as well as with subjective but not objective determinants of disease activity. CONCLUSION: Opioid usage was more likely to be associated with subjective measures (depression, BASDAI, BASFI) than objective measures (CRP, ESR), suggesting that pain in AS may derive from sources other than spinal inflammation alone.

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