Comparative adherence of macitentan versus ambrisentan and bosentan in Australian patients with pulmonary arterial hypertension: a retrospective real-world database study.

AIM: Bosentan, ambrisentan, and macitentan are endothelin receptor antagonists (ERAs), currently available in Australia for treatment of pulmonary arterial hypertension (PAH). This study assessed the comparative adherence of these ERAs for PAH in Australian patients. METHODS: This retrospective, observational study used data for adults with PAH from the Services Australia 10% Pharmaceuticals Benefits Scheme (PBS) dataset (01/2006-10/2020). The primary outcome was treatment adherence (i.e. receiving ≥80% of ERA doses over 12 months). Secondary outcomes were time to treatment change (add-on or switch) and overall survival. RESULTS: The study included 436 patients who took bosentan (n = 200), ambrisentan (n = 69), or macitentan (n = 167). Treatment adherence was significantly greater in patients who received macitentan (65.3%) versus ambrisentan (56.5%) and bosentan (58.0%), with odds ratios (ORs; 95% CI) of 0.51 (0.30-0.88; p = 0.016) for bosentan versus macitentan and 0.48 (0.24-0.96; p = 0.037) for ambrisentan versus macitentan. The median time to treatment change was 47.2 and 43.4 months for bosentan and ambrisentan, respectively (not calculated for macitentan because of insufficient duration of data). LIMITATIONS AND CONCLUSIONS: Real-world data for Australian patients with PAH showed that treatment adherence for ERAs was suboptimal. Adherence was higher for macitentan compared with ambrisentan and bosentan.

Comparative Treatment Persistence and Adherence to Endothelin Receptor Antagonists Among Patients with Pulmonary Arterial Hypertension in Japan: A Real-World Administrative Claims Database Study.

INTRODUCTION: Real-world data on the comparative effectiveness of endothelin receptor antagonists (ERAs; macitentan, bosentan, ambrisentan) for pulmonary arterial hypertension (PAH), particularly in Asian countries, are scarce. We evaluated the persistence of these ERAs before and after macitentan approval in Japan (2015). METHODS: We used real-world data from the Japanese Medical Data Vision administrative claims database between April 2008 and November 2020. Patients with PAH were identified from the dataset. Persistence to ERA treatment before and after approval of macitentan in Japan was defined as the time between start of the index ERA and treatment discontinuation or death. Propensity score adjustment was applied to minimize confounding effects among treatment groups. RESULTS: In the pre-macitentan approval cohort, 153 and 51 patients received bosentan and ambrisentan, respectively. In the post-macitentan approval cohort, 331, 284, and 91 patients received macitentan, bosentan, and ambrisentan, respectively. Unadjusted median persistence for ambrisentan- and bosentan-treated patients was 19 and 10 months, respectively (adjusted HR 0.87 [95% CI 0.61-1.24]; P = 0.434 [bosentan as reference]). In the post-macitentan approval cohort, unadjusted median persistence was 18 months for macitentan-treated patients versus 6 and 8 months for ambrisentan- and bosentan-treated patients, respectively. Adjusted HRs for ambrisentan and bosentan were 1.48 (95% CI 1.12-1.95; P = 0.006) and 1.63 (95% CI 1.30-2.04; P < 0.001 [macitentan as reference]), respectively. CONCLUSIONS: Real-world data for Japanese patients with PAH showed that persistence was significantly higher for macitentan, versus ambrisentan and bosentan, since its approval.

Prevalence, patient characteristics and treatment patterns among SLE-PAH patients in real-world clinical practice: A retrospective analysis of Medical Data Vision Database in Japan.

OBJECTIVE: Real-world evidence regarding prevalence, patient characteristics and treatment patterns for pulmonary arterial hypertension (PAH) related to systemic lupus erythematosus (SLE) in Japan is limited. METHODS: We conducted a retrospective study analysing Japan's Medical Data Vision (MDV) database from April-2008 to September-2020. Prevalence, incidence, patient characteristics, treatment patterns and use of vasodilators by treatment line were evaluated. RESULTS: Prevalence of PAH was 0.392% in SLE patients (n=114/29,077). Cumulative incidence was 0.53% (3-years (y)) and 0.77% (5y). Of 114 SLE-PAH patients, 49% developed PAH <1 year from SLE diagnosis. SLE-PAH patients were more female (88% vs. 72%), had lower mean age at SLE diagnosis (53y vs. 56y) and more severe SLE (61% vs 25%), versus non-PAH SLE patients. Glucocorticoids (58%) and vasodilators (27%) were preferred first-line monotherapy for SLE-PAH. Glucocorticoids+immunosuppressants (19%) was predominant first-line combination therapy. Endothelin receptor antagonists (40% and 44%) and nitric oxide analogues (31% and 40%) were dominant first- and second-line vasodilators. CONCLUSION: SLE-PAH patients were more females, younger at diagnosis, had more severe SLE than non-PAH SLE patients. Most were diagnosed <1 year of SLE diagnosis. In Japan's real-world practice, initial treatment goal is SLE management, while vasodilators are preferred in advanced disease, as per MDV database.

Real-World Evidence for Safety and Effectiveness of Repeated Courses of Hyaluronic Acid Injections on the Time to Knee Replacement Surgery.

Osteoarthritis (OA) of the knee is a top cause of disability among the elderly. Total knee replacement (TKR) has been available as an effective and definite surgical method to treat severe OA of the knee. However, TKR is a significant procedure with potential risk for serious complications and high costs. Alternative lower risk therapies that can delay or obviate TKR are valuable to those who are poor candidates for surgery or wish to avoid TKR as long as possible. Given the chondroprotective effects of hyaluronic acid (HA) injections, they are a safe and effective treatment to improve pain, function, and longevity of the knee. Thus, HA features the potential to delay or obviate TKR. We aim to study the safety and effectiveness of repeated courses of HA on the time to TKR over a 3-year period using data from a large US health plan administrative claims database. Retrospective analyses were conducted by identifying knee OA patients during the selection period (2007-2010). The follow-up period was 36 months, post-index date of initial HA injection. Procedural outcomes and adverse events of interest were tabulated and analyzed. A Cox proportional hazards model was used to model the risk of TKR. A total of 50,389 patients who received HA for treatment of knee OA and met the study inclusion criteria were analyzed. Successive courses of HA showed a good safety profile and led to high proportions of patients without TKR 3 years after treatment initiation. Multivariate statistical modeling showed that multiple courses of HA injections significantly decreased the rates of TKR (95.0% without TKR for ≥5 courses vs 71.6% without TKR for 1 course; hazard ratio, 0.138; P < .0001). Repeated courses of treatment with HA are safe and are associated with the delay of TKR for up to 3 years. Additional research is needed to evaluate the effect of repeated HA courses on delaying TKR beyond a 3-year time horizon.

Clinical and cost outcomes from different hyaluronic acid treatments in patients with knee osteoarthritis: evidence from a US health plan claims database.

BACKGROUND: Intra-articular injection of hyaluronic acid (HA) for knee osteoarthritis (OA) effectively reduces pain and delays total knee replacement (TKR) surgery; however, little is known about relative differences in clinical and cost outcomes among different HA products. OBJECTIVE: To compare disease-specific costs and risk of TKR among patients receiving different HA treatments in a commercially insured cohort of patients with knee OA in the USA. METHOD: Retrospective analyses using IMS Health's PharMetrics Plus Health Plan Claims Database were conducted by identifying knee OA patients with claims indicating initiation of HA treatment at an 'index date' during the selection period (2007-2010). Patients were required to be continuously enrolled in the database for 12 months preindex to 36 months postindex. A generalized linear model (GLM) with a gamma distribution and log-link function was used to model aggregate patient-based changes in disease-specific costs. A Cox proportional hazards model (PHM) was used to model the risk of TKR. Both multivariate models included covariates such as age, gender, comorbidities, and preindex healthcare costs. RESULTS: 50,389 patients with HA treatment for knee OA were identified. 18,217 (36.2%) patients were treated with HA products indicated for five injections per treatment course (Supartz and Hyalgan). The remainder were treated with HA products indicated for fewer than five injections per treatment course, with 20,518 patients (40.7%) receiving Synvisc; 6,263 (12.4%), Euflexxa; and 5,391 (10.7%), Orthovisc. Synvisc- and Orthovisc-injected patients had greater disease-specific costs compared to Supartz/Hyalgan (9.0%, p<0.0001 and 6.8%, p=0.0050, respectively). Hazard ratios (HRs) showed a significantly higher risk of TKR for patients receiving Synvisc compared to Supartz/Hyalgan (HR=1.069, p=0.0009). Patients treated with Supartz/Hyalgan, Euflexxa, and Orthovisc had longer delays to TKR than those treated with Synvisc. CONCLUSION: Analysis of administrative claims data provides real-world evidence that meaningful differences exist among some HA products in disease-specific cost and time to knee replacement surgery.

Evidence for safety of retreatment with a single intra-articular injection of Gel-200 for treatment of osteoarthritis of the knee from the double-blind pivotal and open-label retreatment clinical trials.

BACKGROUND: Gel-200 is a cross-linked hyaluronate single-injection device for treatment of osteoarthritis pain in the knee. This report summarizes new analyses of the safety of retreatment with Gel-200 from the 13-week, pivotal, multicenter, randomized controlled trial (RCT) followed by an open-label extension trial (OLE). METHODS: 379 patients were enrolled in the RCT [Gel-200; phosphate-buffered saline (PBS)]. Safety of retreatment with Gel-200 was assessed by comparing adverse events (AEs) and device-related AEs reported through Week 4 following retreatment with Gel-200 to those reported in patients receiving their first injection in the OLE. RESULTS: 350 patients completed the initial RCT (231 Gel-200; 119 PBS); 258 patients enrolled in the OLE (162 Gel-200; 96 PBS). In total, 202 patients (125 Gel-200; 77 PBS) qualified for retreatment, while 56 (37 Gel-200; 19 PBS) did not. There were no significant demographic or disease characteristic differences between Gel-200 patients who were and were not retreated; those who were not eligible for retreatment experienced greater pain relief from Gel-200 in the RCT by all effectiveness endpoints (all p < 0.001), without differences in their safety profile. In the OLE, the safety of Gel-200, including percentages of patients who experienced any AEs (p = 0.547) and device-related AEs (p = 0.521), did not significantly differ between those receiving a second versus a first injection of Gel-200 following PBS in the RCT. CONCLUSION: In the OLE, the safety of a second injection of Gel-200 was comparable to that of a first injection and effectiveness was similar, as previously reported. TRIAL REGISTRATION: ClinicalTrials.gov identification numbers NTC 00449696 and NTC 00450112.

Hyaluronic Acid Injections Are Associated with Delay of Total Knee Replacement Surgery in Patients with Knee Osteoarthritis: Evidence from a Large U.S. Health Claims Database.

BACKGROUND: The growing prevalence of osteoarthritis (OA) and the medical costs associated with total knee replacement (TKR) surgery for end-stage OA motivate a search for agents that can delay OA progression. We test a hypothesis that hyaluronic acid (HA) injection is associated with delay of TKR in a dose-dependent manner. METHODS AND FINDINGS: We retrospectively evaluated records in an administrative claims database of ~79 million patients, to identify all patients with knee OA who received TKR during a 6-year period. Only patients with continuous plan enrollment from diagnosis until TKR were included, so that complete medical records were available. OA diagnosis was the index event and we evaluated time-to-TKR as a function of the number of HA injections. The database included 182,022 patients with knee OA who had TKR; 50,349 (27.7%) of these patients were classified as HA Users, receiving ≥1 courses of HA prior to TKR, while 131,673 patients (72.3%) were HA Non-users prior to TKR, receiving no HA. Cox proportional hazards modelling shows that TKR risk decreases as a function of the number of HA injection courses, if patient age, gender, and disease comorbidity are used as background covariates. Multiple HA injections are therefore associated with delay of TKR (all, P < 0.0001). Half of HA Non-users had a TKR by 114 days post-diagnosis of knee OA, whereas half of HA Users had a TKR by 484 days post-diagnosis (χ2 = 19,769; p < 0.0001). Patients who received no HA had a mean time-to-TKR of 0.7 years; with one course of HA, the mean time to TKR was 1.4 years (χ2 = 13,725; p < 0.0001); patients who received ≥5 courses delayed TKR by 3.6 years (χ2 = 19,935; p < 0.0001). CONCLUSIONS: HA injection in patients with knee OA is associated with a dose-dependent increase in time-to-TKR.

Heritability of neurocognitive traits in familial schizophrenia.

Neurocognitive deficits are considered promising endophenotypes for gene discovery in schizophrenia. Understanding the heritability and genetic inter-relationships of neurocognitive traits could support their use as alternatives to diagnosis. Participants were 85 adults from 17 multiplex Canadian families with familial schizophrenia linked to 1q23 who had neurocognitive testing results available. Heritability of 13 standard measures assessing motor skills, processing speed, verbal, and visuospatial memory, attention/working memory, executive functioning, and IQ was estimated using variance component models and SOLAR software. We then investigated bivariate relationships between those variables found to be heritable. IQ showed the highest heritability (h(2) = 0.64-0.74) and seven other neurocognitive measures, reflecting immediate and delayed verbal memory, attention/working memory, delayed visual memory, processing speed and motor skills, showed significant heritability (h(2) = 0.31-0.62) under one or more of the models assessed. A schizophrenia diagnostic covariate was significant (P < 0.0001) for all heritable variables. Bivariate analyses suggested that memory-IQ and visuomotor-processing speed formed two groups of heritable traits. The results provide further evidence of the heritability of selected neurocognitive measures, and their relationship to schizophrenia and underlying genetic architecture. Composite measures of memory or processing speed may be heritable phenotypes useful for studies of neurocognition.

Reduced proportions of natural killer T cells are present in the relatives of lupus patients and are associated with autoimmunity.

INTRODUCTION: Systemic lupus erythematosus is a genetically complex disease. Currently, the precise allelic polymorphisms associated with this condition remain largely unidentified. In part this reflects the fact that multiple genes, each having a relatively minor effect, act in concert to produce disease. Given this complexity, analysis of subclinical phenotypes may aid in the identification of susceptibility alleles. Here, we used flow cytometry to investigate whether some of the immune abnormalities that are seen in the peripheral blood lymphocyte population of lupus patients are seen in their first-degree relatives. METHODS: Peripheral blood mononuclear cells were isolated from the subjects, stained with fluorochrome-conjugated monoclonal antibodies to identify various cellular subsets, and analyzed by flow cytometry. RESULTS: We found reduced proportions of natural killer (NK)T cells among 367 first-degree relatives of lupus patients as compared with 102 control individuals. There were also slightly increased proportions of memory B and T cells, suggesting increased chronic low-grade activation of the immune system in first-degree relatives. However, only the deficiency of NKT cells was associated with a positive anti-nuclear antibody test and clinical autoimmune disease in family members. There was a significant association between mean parental, sibling, and proband values for the proportion of NKT cells, suggesting that this is a heritable trait. CONCLUSIONS: The findings suggest that analysis of cellular phenotypes may enhance the ability to detect subclinical lupus and that genetically determined altered immunoregulation by NKT cells predisposes first-degree relatives of lupus patients to the development of autoimmunity.

Gene by environment interactions.

This paper summarizes the contributions of group 8 to the Genetic Analysis Workshop 15. Group 8 focused on ways to address the possibility that genetic and environmental effects on phenotype may not be independent, but instead may interact in ways that could play important roles in determining phenotype. Among the eight contributors to this group, all three data sets (expression data, rheumatoid arthritis data, and simulated data) were analyzed. Contributions to this section fell into the two broad categories of refining the data (e.g. stratifying or weighting based on a covariate value) and explicitly modeling the interactions. The contributions also illustrate that there are at least two possible goals for such studies. One goal is simply to identify factors contributing to phenotype in the presence of interactions that might mask the signal to univariate methods. A related but distinct goal is to characterize an interaction (e.g. to determine if the interaction is significant).

VEGF, FGF1, FGF2 and EGF gene polymorphisms and psoriatic arthritis.

BACKGROUND: Angiogenesis appears to be a first-order event in psoriatic arthritis (PsA). Among angiogenic factors, the cytokines vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), and fibroblast growth factors 1 and 2 (FGF1 and FGF2) play a central role in the initiation of angiogenesis. Most of these cytokines have been shown to be upregulated in or associated with psoriasis, rheumatoid arthritis (RA) or ankylosing spondylitis (AS). As these diseases share common susceptibility associations with PsA, investigation of these angiogenic factors is warranted. METHODS: Two hundred and fifty-eight patients with PsA and 154 ethnically matched controls were genotyped using a Sequenom chip-based MALDI-TOF mass spectrometry platform. Four SNPs in the VEGF gene, three SNPs in the EGF gene and one SNP each in FGF1 and FGF2 genes were evaluated. Statistical analysis was performed using Fisher's exact test, and the Cochrane-Armitage trend test. Associations with haplotypes were estimated by using weighted logistic models, where the individual haplotype estimates were obtained using Phase v2.1. RESULTS: We have observed an increased frequency in the T allele of VEGF +936 (rs3025039) in control subjects when compared to our PsA patients [Fisher's exact p-value = 0.042; OR 0.653 (95% CI: 0.434, 0.982)]. Haplotyping of markers revealed no significant associations. CONCLUSION: The T allele of VEGF in +936 may act as a protective allele in the development of PsA. Further studies regarding the role of pro-angiogenic markers in PsA are warranted.

Association of toll-like receptor 4 variants and ankylosing spondylitis: a case-control study.

OBJECTIVE: Functional single nucleotide polymorphisms within the ectoplasmic domain of the Toll-like receptor 4 (TLR4) gene have been shown to result in an endotoxin-hyporesponsive phenotype and aberrant signal transduction for bacterial agonists. TLR4 is in proximity to a genome-wide linkage peak in 9q32-33. Given the proposed function and location of TLR4, we examined the association of 2 functional variants of TLR4 in patients with ankylosing spondylitis (AS) in Newfoundland. METHODS: In total, 101 AS patients and 100 ethnically matched controls were genotyped, using the Sequenom MassArray platform, for 2 functional variants in the TLR4 gene: Asp299Gly (A/G polymorphism) and Thr399Ile (C/T polymorphism). RESULTS: The minor allele frequency for the Asp299Gly variant (G) was significantly higher in AS cases compared to controls (7.5% vs 2.6%, respectively; OR 3.10, p = 0.037). The minor allele frequency for the Thr399Ile variant (T) for cases and controls was 7.4% vs 3.0% (OR 2.59, p = 0.071). Haplotype analysis using Haploview noted a higher proportion of GT in the cases (for GT, chi-squared p = 0.023). CONCLUSION: Given the functional role of TLR4 variants in the innate immune system, larger studies are now warranted to elucidate the association of TLR4 variants in AS.

Association between serum total cholesterol level and renal outcome in systemic lupus erythematosus.

OBJECTIVE: To determine whether an elevated serum total cholesterol level in a first-available sample obtained at a systemic lupus erythematosus (SLE) clinic is associated with worse renal outcome in patients with SLE. METHODS: Survival analysis methods were used on prospectively gathered data on 1,060 patients with SLE who were registered in the University of Toronto Lupus Databank. The effect of total cholesterol and 15 additional variables on the outcomes of renal deterioration, end-stage renal disease (ESRD), and death was assessed using Cox proportional hazards methods. RESULTS: In 474 (45%) of the 1,060 patients, the total cholesterol level exceeded 5.2 mmoles/liter. In the entire study group, the median total cholesterol level was 5.1 mmoles/liter (range 1.6-17.1). During a mean followup period of 8.8 years, 93 patients (9%) experienced renal deterioration, 42 patients (4%) had ESRD, and 161 deaths occurred, 48 (30%) of which were associated with renal dysfunction (renal death), and 113 (70%) of which were not associated with renal dysfunction (nonrenal death). Kaplan-Meier survival estimates for each outcome were statistically significantly different between patients with normal versus those with elevated total cholesterol levels (cutoff 5.2 mmoles/ liter), with a worse outcome observed among those with an elevated total cholesterol concentration. In multivariate analyses, total cholesterol level (hazard ratio [HR] 1.17, 95 confidence interval [95% CI] 1.01-1.36), serum creatinine level (HR 1.06, 95% CI 1.04-1.07), proteinuria (HR 2.44, 95% CI 1.25-4.76), the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (HR 1.44, 95% CI 1.16-1.80), and corticosteroid dose (HR 1.01, 95% CI 1.00-1.02) were associated with renal deterioration. Significant predictors of ESRD were baseline proteinuria (HR 6.24, 95% CI 1.96-19.88) and serum creatinine level (HR 1.15, 95% CI 1.08-1.22). The total cholesterol level was correlated with death (HR 1.20, 95% CI 1.11-1.29), retaining statistical significance for renal death (HR 1.33, 95% CI 1.20-1.47) but not for nonrenal death (HR 1.12, 95% CI 0.99-1.25). CONCLUSION: Those results indicate that an elevated serum total cholesterol level in a first-available sample obtained at an SLE clinic is associated with adverse renal outcomes and mortality.

Continuous covariates in genetic association studies of case-parent triads: gene and gene-environment interaction effects, population stratification, and power analysis.

We propose a multinomial logistic regression method which permits estimation and likelihood ratio tests for allele effects, their interactions with continuous covariates, and assessment of the degree of population stratification in genetic association studies of case-parent triads. Our approach overcomes the constraint imposed by the categorical nature of explanatory variables in the log-linear model. We also demonstrate that the multinomial logistic method can yield efficient inference in the presence of missing parental genotype data via the use of the Expectation-Maximization (EM) algorithm. We performed simulations to compare the multinomial logistic model with the case-pseudosibling conditional logistic model approach, both of which permit the incorporation of continuous covariates. Simulation results indicate that the multinomial logistic model and the conditional logistic model lead to similar estimates in large samples. A simulation-based method of sample size estimation is also used to show that the two models are approximately equivalent in sample size requirements. When parental genotype data are missing, either completely at random or dependent on covariates, the use of the EM algorithm gives multinomial logistic model greater power. Since the multinomial logistic model offers the possibility of assessing the degree of population stratification in the sample and can also provide efficient inference in the presence of missing parental genotypes, the proposed model has an important application in epidemiological family-based association studies.