When Should I Get My Next COVID Vaccine? Data from the SUrveillance of responses to COVID-19 vaCcines in systEmic immunE mediated inflammatory Diseases (SUCCEED)study

OBJECTIVE

To determine how serologic responses to COVID vaccination/infection in immunemediated inflammatory disease (IMID) are affected by time since last vaccination and other factors.

METHODS

Post-COVID-19 vaccination, data and dried blood spots/sera were collected from adults with rheumatoid arthritis, inflammatory bowel disease, systemic lupus, ankylosing spondylitis/spondylarthritis and psoriasis/psoriatic arthritis. First sample was at enrolment and then 2-4 weeks and 3, 6, and 12 months after latest vaccine dose. Multivariate generalized estimating equation regressions (including medications, demographics, and vaccination history) evaluated serologic response, based on log-transformed anti-RBD IgG titres; we also measured anti-nucleocapsid IgG.

RESULTS

Positive associations for log-transformed anti-RBD titres were seen with female sex, number of doses, and self-reported COVID infections in 2021-2023. Negative associations were seen with prednisone, anti-TNF agents, and rituximab.Over 2021-2023, most (94%) of anti-nucleocapsid positivity was associated with a self-reported infection in the 3 months prior. From March 2021 to Feb 2022, anti-nucleocapsid positivity was present in 5-15% of samples and was highest in the post-Omicron era, with anti-nucleocapsid positivity trending to 30-35% or higher as of March 2023. Anti-nucleocapsid positivity in IMID remained lower than Canada's general population seroprevalence (>50% in 2022 and >75% in 2023).Time since last vaccination was negatively associated with log-transformed anti-RBD titres, particularly after 210 days.

CONCLUSION

Ours is the first pan-Canadian IMID assessment of how vaccine history and other factors affect serologic COVID-19 vaccine responses. These findings may help individuals personalize vaccination decisions, including consideration of additional vaccination when >6 months has elapsed since last COVID vaccination/infection.

COVID-19 Vaccine in Immunosuppressed Adults with Autoimmune rheumatic Diseases (COVIAAD): safety, immunogenicity and antibody persistence at 12 months following Moderna Spikevax primary series

OBJECTIVE

To assess the safety, immunogenicity and cellular responses following the Moderna Spikevax primary series in rheumatic disease.

METHODS

We conducted a 12-month, prospective, non-randomised, open-label, comparative trial of adults with either rheumatoid arthritis (RA, n=131) on stable treatment; systemic lupus erythematosus (SLE, n=23) on mycophenolate mofetil (MMF); other rheumatic diseases on prednisone ≥10 mg/day (n=8) or age-matched/sex-matched controls (healthy control, HC, n=58). Adverse events (AEs), humoral immune responses (immunogenicity: IgG positivity for anti-SARS-CoV-2 spike protein and its receptor binding domain, neutralising antibodies (NAbs)), cellular responses (ELISpot) and COVID-19 infection rates were assessed.

RESULTS

Frequency of solicited self-reported AEs following vaccination was similar across groups (HC 90%, RA 86%, SLE 90%); among them, musculoskeletal AEs were more frequent in RA (HC 48% vs RA 66% (Δ95% CI CI 3 to 32.6)). Disease activity scores did not increase postvaccination. No vaccine-related serious AEs were reported. Postvaccination immunogenicity was reduced in RA and SLE (RA 90.2%, SLE 86.4%; for both, ΔCIs compared with HC excluded the null). Similarly, NAbs were reduced among patients (RA 82.6%, SLE 81.8%). In RA, age >65 (OR 0.3, 95% CI 0.1 to 0.8) and rituximab treatment (OR 0.003, 95% CI 0.001 to 0.02) were negative predictors of immunogenicity. ELISpot was positive in 16/52 tested RA and 17/26 HC (ΔCI 11.2-53.3). During the study, 11 HC, 19 RA and 3 SLE patients self-reported COVID-infection.

CONCLUSION

In COVID-19 Vaccine in Immunosuppressed Adults with Autoimmune Diseases, the Moderna Spikevax primary series was safe. MMF, RA age >65 and rituximab were associated with reduced vaccine-induced protection.

Heritability and environmental influences on the onset of aortic valve sclerosis: a twin population study

Background

Aortic valve sclerosis (AVSc) is the earliest manifestation of a life-threatening cardiovascular disorder, namely aortic valve stenosis (AS). AVSc is also recognized as a red flag linked to worse cardiovascular outcomes in high-risk coronary artery disease patients. However, the genetic background of AVSc is still unknown.

Purpose

To examine whether the heritability and environmental contributions play a role in the onset of AVSc using a sample of Italian twins.

Methods

The present study is based on the classical twin design. Twins, aged 50 to 70 years, already enrolled in the Italian Twin Register, were contacted and invited to undergo a clinical, echocardiographic, and complete carotid artery ultrasound examination at the our Center, between July 2017 and December 2021. The presence of AVSc was recognized as non-uniform thickening with or without spotty calcified areas of the aortic valve leaflets without a significant transvalvular gradient (maximum aortic velocity <2.5 m/s). Twin zygosity was assessed through a questionnaire on physical similarity during childhood, known to be ∼95% accurate. Tetrachoric twin correlations by zygosity were estimated with Mx Software using liability threshold saturated models and incorporating age as a covariate. Liability-threshold structural equation modelling was performed to decompose the phenotypic variance into contributions due to additive genetic (A), common environmental (C), and unique environmental (E) effects.

Results

A total of 216 adult twins (66 monozygotic, MZ and 42 dizygotic pairs, DZ; mean age 59.9±6.2) were enrolled in the study. The estimated prevalence rate of AVSc in the total sample was 29.2%. As significant sex differences were detected (males 45.2% and females 22.7%, p<0.01), the additional twin analyses were performed as intra-sex analyses. Females showed a greater tetrachoric correlation in MZ twins (r=0.37) compared to DZ twins (r=0.23), suggesting the existence of a genetic influence. Genetic factors, under the best (AE) model, accounted for 38% of the variance in liability to AVSc with the remaining contribution due to unique environmental influences (E = 62%). The contribution of the common environment (C) to the goodness of fit was negligible. The male group was too small for statistical calculation.

Conclusion

To our knowledge, the present study is the first to document the involvement of genetic factors in the development of AVSc. Our data also warrant further studies to both validate the findings obtained and to better explore the heritability of AVSc. Furthermore, our results provide a first evidence that an echocardiographic screening in individuals with relatives affected by AVSc has a scientific rational basis.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Italian Ministry of Health

High Frequency of COVID-19 Vaccine Hesitancy among Canadians Immunized for Influenza: A Cross-Sectional Survey

We assessed the frequency and correlates of COVID-19 vaccine hesitancy before Canada's vaccine rollout. A cross-sectional vaccine hesitancy survey was completed by consecutive patients/family members/staff who received the influenza vaccine at McGill University affiliated hospitals. Based on the self-reported likelihood of receiving a future vaccine (scale 0-10), the following three groups were defined: non-hesitant (score 10), mildly hesitant (7.1-9.9), and significantly hesitant (0-7). Factors associated with vaccine hesitancy were assessed with multivariate logistic regression analyses and binomial logistic regression machine learning modelling. The survey was completed by 1793 people. Thirty-seven percent of participants (n = 669) were hesitant (mildly: 315 (17.6%); significantly: 354 (19.7%)). Lower education levels, opposition and uncertainty about vaccines being mandatory, feelings of not receiving enough information about COVID-19 prevention, perceived social pressure to get a future vaccine, vaccine safety concerns, uncertainty regarding the vaccine risk-benefit ratio, and distrust towards pharmaceutical companies were factors associated with vaccine hesitancy. Vaccine safety concerns and opposition to mandatory vaccinations were the strongest correlates of vaccine hesitancy in both the logistic regressions and the machine learning model. In conclusion, in this study, over a third of people immunized for influenza before the COVID-19 vaccine rollout expressed some degree of vaccine hesitancy. Effectively addressing COVID-19 vaccine safety concerns may enhance vaccine uptake.

Safety and Efficacy of Influenza Vaccination in Patients Receiving Immune Checkpoint Inhibitors. Systematic Review with Meta-Analysis

The potential increased risk of immune-related adverse events (irAEs) post-influenza vaccine is a concern in patients receiving immune checkpoint inhibitors (ICI). We conducted a systematic review with meta-analysis of studies reporting the effects of influenza vaccination in patients with cancer during ICI treatment. We searched five electronic databases until 01/2022. Two authors independently selected studies, appraised their quality, and collected data. The primary outcome was the determination of pooled irAE rates. Secondary outcomes included determination of immunogenicity and influenza infection rates and cancer-related outcomes. Nineteen studies (26 publications, n = 4705) were included; 89.5% were observational. Vaccinated patients reported slighter lower rates of irAEs compared to unvaccinated patients (32% versus 41%, respectively). Seroprotection for influenza type A was 78%-79%, and for type B was 75%. Influenza and irAE-related death rates were similar between groups. The pooled proportion of participants reporting a laboratory-confirmed infection was 2% (95% CI 0% to 6%), and influenza-like illness was 14% (95% CI 2% to 32%). No differences were reported on the rates of laboratory-confirmed infection between vaccinated and unvaccinated patients. Longer progression-free and overall survival was also observed in vaccinated compared with unvaccinated patients. Current evidence suggests that influenza vaccination is safe in patients receiving ICIs, does not increase the risk of irAEs, and may improve survival.

Sex-specific cell types and molecular pathways drive fibro-calcific aortic valve stenosis

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Fondazione Gigi e Pupa Ferrari ONLUS

Background

Aortic stenosis (AS) is the most common valve disorder characterized by fibro-calcific remodeling of valve leaflets. Recent evidence indicated that there is a sex-related difference in AS development and progression. Fibrotic remodeling is peculiar of women's aortic valve, while men's aortic leaflets are more calcified than in women.

Purpose

To assess aortic valve fibrosis (AVF) in a severe AS cohort using non-invasive diagnostic tools and determine whether sex-specific pathological pathways and cell types are associated with severe AS.

Methods

We have included 28 men and 28 women matched for age with severe AS who underwent Doppler echocardiography and cardiac contrast-enhanced computed tomography (CT) before intervention. The calcium and fibrosis volumes were assessed and quantified using the ImageJ thresholding method, indexed calcium and fibrosis volume were calculated by dividing the volume by the aortic annular area. Differentially expressed genes and functional inferences between women and men's aortic valves were carried out on a publicly available microarray-based gene expression dataset (GSE102249). Cell types enrichment analysis in stenotic aortic valve tissues was used to reconstruct the sex-specific cellular composition of stenotic aortic valves.

Results

We confirmed that women had significantly lower aortic valve calcium content compared to men, while fibrotic tissue composition was significantly higher in women than men. We identified that the expression profile of human stenotic aortic valves is sex-dependent. Pro-fibrotic processes were prevalent in women, while pro-inflammatory ones, linked to the immune response system, were enhanced in men. Cell-type enrichment analysis showed that mesenchymal cells were over-represented in AS valves of women, whereas signatures for monocytes, macrophages, T and B cells were enriched men ones.

Conclusions

Our data provide the basis that the fibro-calcific process of the aortic valve is sex-specific, both at gene expression and cell type level. The quantification of aortic valve fibrosis by CT could make it possible to perform population-based studies and non-invasive assessment of novel therapies to reduce or halt sex-related calcific aortic valve stenosis (CAVS) progression, acting in an optimal window of opportunity early in the course of the disease.

Unravelling sex-dependent mechanisms in calcific aortic valve stenosis

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Italian Ministry of Health

Background

Calcific aortic valve stenosis (CAVS) is the most common heart valve disease that affects 3% of the population. CAVS is a progressive, multifactorial disorder driven by several cellular and molecular pathological processes. Currently, there is no pharmacological therapy able to prevent CAVS progression. Little is known about the sex-related difference in molecular mechanisms. Recent studies reported that men showed a higher aortic valve calcium load than women, which in turn, developed more fibrosis in the stenotic aortic valve leaflets. Hence, it has been hypothesized that the mechanisms underlying CAVS progression could be different between the two sexes.

Purpose

To investigate sex-differences in CAVS molecular pathways, finding new sex-related pharmacological targets.

Methods

Valve interstitial cells (VIC) were isolated from 26 patients who underwent aortic valve replacement for aortic valve stenosis. RNA, extracted from VICs, was sequenced by third generation sequencing technology. We performed pro-fibrotic (TGFβ) treatment for 5 days and we evaluated soluble collagen expression by a colorimetric assay and αSMA expression by western blot. We evaluated extracellular calcium extent by a colorimetric assay on VICs exposed to pro-calcific (inorganic phosphate) medium for 7 days. We assessed the mitochondrial damage with mitoSOX staining by Imagestream.

Results

The gene expression analysis from sequenced VICs revealed 65 genes upregulated in men and 89 genes upregulated in women. The functional analysis showed that the TGFβ signaling resulted enriched in woman VICs, while the mitochondrial related genes were upregulated in man VICs. Only woman VICs secreted higher amount of collagen under TGFβ treatment respect to the untreated (1.22±0.03 fold change (FC) vs. untreated, p<0.001). αSMA expression (marker of VICs activation) was significantly higher both in men and women exposed to different concentrations of TGFβ (TGFβ 5ng/ml: 1.88±0.34 in men and 2.66±0.32 in women, FC vs. untreated, p=0.003 and p<0.0001, respectively; TGFβ 10ng/ml: 2.96±0.55 in men and 2.16±0.35 in women, FC vs. untreated, p=0.0003 and p=0.0006, respectively). The calcification potential of VICs exposed to pro-calcific medium was higher in men than in women (8.23±0.45 vs. 4.69±0.59 FC vs. untreated, respectively, p<0.0001). The mitochondrial superoxide formation in man VICs was higher than in woman VICs at steady state (51.0±2.1% vs. 29.5±0.9% of positive cells, respectively, p<0.0001)

Conclusion

CAVS progression seems to be driven by sex-dependent molecular pathways activation. In particular, pro-fibrotic pathways are upregulated in women, while pro-calcific pathways and mitochondrial damage in men. Our data pave the way to sex-dependent pharmacological target research, aiming to treat CAVS patients.

Influenza Vaccine Hesitancy and Its Determinants Among Rheumatology Patients

Objective

Patients with rheumatic disease (RD) have an increased risk of influenza and its complications. Despite inactivated influenza vaccine (IIV) recommendations, IIV uptake in patients with RD is suboptimal, a problem of increasing importance in the COVID‐19 era. We estimated the frequency of IIV hesitancy and associated factors among Canadian patients with RD.

Methods

A cross‐sectional vaccine hesitancy survey was completed by rheumatology clinic patients (November 2019 to January 2020). Patients rated their likelihood of receiving the influenza vaccine (scale of 0‐10). We categorized these as follows: likely to refuse (scale of 0‐2), uncertain (scale of 3‐7), or likely to accept (scale of 8‐10). Multivariate logistical regression was used to evaluate factors associated with vaccine hesitancy.

Results

A total of 282 patients (63.5% of those approached) completed the survey, with 165 (58.5%) being likely to accept, 67 (23.8%) being likely to refuse, and 50 (17.7%) uncertain. Uncertain patients were younger and more likely to be employed than those in the other two groups. No previous influenza vaccination (odds ratio [OR] 36.6, 95% confidence interval [CI] 5.3‐252.9), belief that vaccination should not be mandatory (OR 0.1, 95% CI 0.0‐0.7), unwillingness to take time off work to be vaccinated (OR 6.8, 95% CI 1.5‐30.6), and distrust in pharmaceutical companies (OR 41.0, 95% CI 5.6‐301.5) predicted likeliness to refuse. Reluctance to pay for vaccination (OR 2.8, 95% CI 1.1‐7.5) and no previous influenza vaccination (OR 18.9, 95% CI 3.3‐109.7) predicted uncertainty.

Conclusion

More than 40% of rheumatology patients are either likely to refuse or uncertain about receiving IIV. This contributes to suboptimal vaccine coverage in this population. Interventions addressing these concerns are needed, particularly in the COVID‐19 era.

Barriers and facilitators to influenza and pneumococcal vaccine hesitancy in rheumatoid arthritis: a qualitative study

OBJECTIVE

Immunization is an essential component of rheumatoid arthritis (RA) care. Nevertheless, vaccine coverage in RA is suboptimal. Contextual, individual, and vaccine-related factors influence vaccine acceptance. However, barriers and facilitators of vaccination in RA are not well defined. The aim of this study was to assess perspectives of RA patients and health care professionals (HCPs) involved in RA care of barriers and facilitators regarding influenza and pneumococcal vaccines.

METHODS

Eight focus groups (4 with RA patients and 4 with HCPs), and eight semi-structured open-ended individual interviews with vaccine hesitant RA patients were conducted. Data were audio-recorded, transcribed verbatim, and imported to the MAXQDA software. Analysis using the framework of vaccine hesitancy proposed by the Strategic Advisory Group of Experts (SAGE) on Immunization was conducted.

RESULTS

RA patients and HCPs reported common and specific barriers and facilitators to influenza vaccination that included contextual, individual and/or group, and vaccine and/or vaccination specific factors. A key contextual influence on vaccination was patients' perception of the media, pharmaceutical industry, authorities, scientists, and the medical community at large. Among the individual-related influences, experiences with vaccination, knowledge/awareness, and beliefs about health and disease prevention were considered to impact vaccine-acceptance. Vaccine-related factors including concerns of vaccine side effects such as RA flares, safety of new formulations, mechanism of action, access to vaccines and costs associated with vaccination were identified as actionable barriers.

CONCLUSION

Acknowledging RA patients' perceived barriers to influenza and pneumococcal vaccination and implementing specific strategies to address them might increase vaccination coverage in this population.

POS1268 COVID-19 VACCINE HESITANCY AMONG RHEUMATOLOGY PATIENTS RECEIVING INFLUENZA VACCINE

Background:

Adults with rheumatic diseases are a COVID-19 vulnerable population with potential increased risk for severe infection. COVID-19 vaccines are a key strategy to ending the pandemic. Unfortunately, fears about vaccines, some of which are propagated by misinformation, are common and may prevent or inappropriately delay vaccination. Refusal or uncertainty to get a vaccine despite its availability is known as vaccine hesitancy.

Objectives:

This study aims at defining causes of COVID-19 vaccine hesitancy among rheumatology patients.

Methods:

Between November and December 2020, a cross-sectional survey was completed by rheumatology patients presenting to a large Canadian tertiary-care center for influenza immunization. COVID-19 risk factors, previous COVID-19 infection, the likelihood of getting a future COVID-19 vaccine (scale 0-10), and contextual, individual, and vaccine-specific potential determinants of vaccine hesitancy were assessed. Patients were classified into 5 groups based on how likely they were to get a future COVID-19 vaccine (0= not likely at all; 2.5= unlikely; 5= intermediate; 7.5= likely; 10= highly likely). A machine learning approach (XgBoost) was used to fit univariate models for a multi-class correlation.

Results:

157 rheumatology patients completed the survey. Most were females (n=112, 71%) with a mean age of 54.6 (standard deviation 17.9). The majority (73%) had tertiary-education, and 46% were employed at the time of the survey. The most common rheumatology diagnoses were rheumatoid arthritis (n=90, 58%), systemic lupus erythematosus/vasculitis (n=41, 26%) and spondyloarthropathies (n=39, 25%). Most patients were on immunosuppressors (n=93, 59%). Only half (n=85, 54%) were highly likely to accept a future COVID vaccine, 17% (n=26) likely, 19% (n=30) intermediate, 6% (n=10) unlikely, and 4% (n=6) not likely at all. One hundred thirty-five patients (86%) previously received the flu vaccine, whereas 6% (n=10) previously rejected it. Only three patients were previously diagnosed with COVID-19 (2%) one of whom was hospitalized. Eighty-seven patients (56%) considered that the COVID-19 vaccine should be mandatory, and 101 (65%) that they should receive it. Most respondents were somewhat concerned about receiving a future COVID-19 vaccine (n=116, 76%) despite that 65% believed that vaccines benefits outweighed their risks. Almost all, (n=145, 96%) believed that governmental decisions about vaccines are in the best interest of the population, while less than half (n=70, 45%) were confident that pharmaceutical companies would provide safe and effective vaccines. One hundred participants (65%) denied feeling social pressure to get the vaccine, and 55% (n=81) were willing to pay for the vaccine. Feeling social pressure about getting a COVID-19 vaccine, having severe concerns about receiving a future COVID-19 vaccine, distrust in pharmaceutical companies, lower education, and doubts of whether vaccines benefits outweigh their risks, were negatively associated with COVID vaccine acceptance.

Conclusion:

Forty six percent of rheumatology patients being immunized against influenza showed at least some hesitancy towards COVID-19 vaccination. Multiple contextual, individual, and vaccine-related factors may contribute. Targeted educational strategies, including producing and communicating data on vaccine safety, may help promote vaccine uptake in this potentially vulnerable population.

Disclosure of Interests:

None declared

A multimodal intervention increases influenza vaccine uptake in rheumatoid arthritis

Annual influenza vaccination is recommended for patients with rheumatoid arthritis (RA), but coverage is suboptimal. We assessed the impact of an implementation strategy in enhancing vaccination uptake in RA. We evaluated a multimodal implementation strategy at rheumatology clinics that included 3 approaches: patient recalls, a nurse providing vaccines, and physician reminders. We compared patient-reported vaccination rates after implementation with those reported before the implementation strategy in a nonequivalent control group. In multivariate analyses, we assessed factors potentially associated with influenza vaccine uptake. One hundred and sixteen RA patients were vaccinated during the intervention. The influenza vaccination rate in RA increased from 48.5% (65/136) before implementation to 62.6% (67/107) after implementation (difference of 14.1, 95% CI 1.5, 26.1). In multivariate analyses, older age, biologics use, and physician recommendation for vaccination were associated with influenza vaccine uptake. A multimodal intervention was associated with increased influenza vaccine coverage among RA patients. Older patients and those on biologics were more likely to be immunized against influenza. Physician's recommendations are important to promote vaccine coverage. Key Points • Despite current recommendations, influenza vaccine uptake among rheumatoid arthritis (RA) patients is suboptimal. • A multimodal implementation strategy facilitating access to influenza vaccine and raising awareness through vaccination reminders improved immunization uptake in RA. • Physicians play a key role in promoting annual seasonal influenza vaccination. • The reasons for vaccine hesitancy in RA should be addressed to reach a vaccination target of 80% required to reduce the burden of this preventable infection.

THU0154 PERCEPTIONS ABOUT INTERVENTIONS TO ENHANCE INFLUENZA VACCINE UPTAKE DIFFER BETWEEN VACCINATED AND UNVACCINATED RA/JIA PATIENTS

Background:

To optimize the control of vaccine preventable diseases, high immunization coverage rates must be achieved. Influenza vaccination rates among patients with rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA) are suboptimal. Understanding patient preferences for interventions that may increase vaccine uptake is the first step to inform the development of specific strategies to enhance vaccine coverage in RA/JIA.

Objectives:

To compare the perceptions of vaccinated and unvaccinated RA/JIA patients on a multi-modal intervention to enhance seasonal influenza vaccine coverage.

Methods:

During the 2018-2019 influenza season, a multi-modal intervention was implemented at a large Canadian academic center. This consisted of (i) a letter sent from the Division of Rheumatology to patients addressing common misconceptions about flu vaccines and encouraging patients to plan for immunization; (ii) a nurse providing inactivated influenza vaccine at the rheumatology clinics for the first 7 weeks after the vaccine was released, and (iii) clinics posters specifically designed for rheumatic patients and rheumatologists to prompt a discussion on influenza prevention. Patients that were vaccinated on site completed a survey evaluating the relevance of the individual components of the intervention. After the intervention, during a scheduled rheumatology visit, RA/JIA patients were asked to complete a similar survey. We compared the responses from RA/JIA patients that were vaccinated at our institution, to those of patients that reported not having received the influenza vaccine in 2018-2019.

Results:

During the intervention, 116 immunized RA/JIA patients completed the first survey. Forty RA/JIA patients not vaccinated during the 2018-2019 season completed the post-intervention survey. Both vaccinated and unvaccinated groups were mostly female (74.1% versus 87.2%), but vaccinated patients were older (50.8±19.4 versus: 40.5±14.9; 95% CI 3.7%,17%), and had shorter disease duration (10.1±9.3 versus 15.0±9.8; 95% CI -8.9%,-1.1%) than those not vaccinated. Unvaccinated patients were less likely than vaccinated patients to approve of the clinic’s provision of influenza vaccine (98.2% versus 75%; 95% CI 12.8%, 43.5%). When asked about elements of the intervention, unvaccinated patients were less likely than vaccinated patients to consider posters (65.2% versus 38.9%; 95% CI 7.9%, 42.9%), letters (69.4% versus 35.3%; 95% CI 16.2%, 51.2%), or phone calls (58.0% versus 41.7%; 95% CI 2.1%, 33.5%) as good reminders.

Conclusion:

Unvaccinated RA/JIA patients’ opinions about interventions to increase vaccine uptake differ from vaccinated patients. Alternative, novel strategies to target vaccine hesitant RA/JIA patients are needed to optimize vaccine coverage.

Disclosure of Interests:

None declared

P4667Loss of function in PCSK9, atherogenic lipoprotein concentrations, and calcific aortic valve stenosis

Background

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition reduces plasma concentrations of most atherogenic lipoproteins such as low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (apoB) and lipoprotein(a) [Lp(a)]. Atherogenic lipoprotein concentrations have also been linked with calcific aortic valve stenosis (CAVS).

Purpose

1) To determine the association between genetic variants in PCSK9 and lipoprotein-lipid levels, 2) to determine whether loss of function (LOF) in PCSK9 is associated with CAVS and 3) to evaluate if PCSK9 could be implicated in aortic valve interstitial cells (VICs) calcification.

Methods

We built a weighted genetic risk score (wGRS) using 10 single nucleotide polymorphisms at the PCSK9 locus associated with LDL-C in the Global Lipids Genetics Consortium. We determined the association between the wGRS and LDL-C, apoB and Lp(a)] in 9692 participants of the EPIC-Norfolk study using linear regression. We investigated the association between the LOF PCSK9 R46L variant and CAVS risk in a meta-analysis of published (three Copenhagen studies, 1463 cases and 101,620 controls) and unpublished studies (UK Biobank, 1350 cases and 349,043 controls, Malmö Diet and Cancer study, 682 cases and 5963 controls and EPIC-Norfolk, 508 cases and 20,421 controls) prospective, population-based studies using logistic regression adjusted for age and sex. We evaluated PCSK9 expression and localization in explanted aortic valves by capillary Western blot and immunohistochemistry in patients with and without CAVS. Von Kossa staining was used to visualize aortic leaflet calcium deposits. We also assessed VICs calcification potential under oxidative stress condition.

Results

In EPIC-Norfolk, the wGRS was significantly associated with TC, LDL-C, and apoB (all p<0.0001), but not with VLDL-C, HDL-C, triglycerides apoA-I, or Lp(a). Carriers of the R46L variant were at lower CAVS risk (odds ratio=0.71 (95% CI, 0.57–0.88, p<0.001)). Aortic valves of patients with aortic sclerosis (n=12) and CAVS (n=8) presented elevated PCSK9 levels (log2 fold change [FC]=+28.6±5.1, p=0.008 and FC=+39.3±15.2, p=0.02, respectively) compared to controls (n=4).In calcified leaflets, PCSK9 expression co-localized with calcium deposits. PCSK9 expression in VICs was induced by oxidative stress (FC=+2.3±0.4, p=0.02), and subsequent increment in calcification potential was observed.

Conclusion

PCSK9LOF variants are associated with lifelong reductions in non-Lp(a) apoB-containing lipoprotein levels and a lower risk of coronary artery disease and CAVS. PCSK9 is abundant in fibrotic and calcified aortic leaflets. Oxidative stress increases PCSK9 expression in VICs. These results support randomized clinical trials of PCSK9 inhibition in the prevention of CAVS.

[Differences in the symptomatology of paroxysmal supraventricular tachycardias in relation to the different sites of localization of the arrhythmic reentry circuit. Clinical picture, semiologic and genetic aspects]

Transesophageal, electrophysiologic studies were conducted in 47 patients, with clinical and ECGgraphic diagnosis of paroxysmal reciprocating supraventricular tachycardia. After admission to hospital, the patients were enrolled in the study in accordance with the criterion concerning the exclusion of patients with signs and symptoms of severe heart pump failure (ie, NYHA III and IV class were excluded). The transesophageal study was performed during paroxysmal tachycardia in each patient to measure the V-A interval and to localize the site of reentry. Thereby, the patients could be grouped into 2 subsets, ie those with A-V nodal reentrant tachycardia (no. 30 patients) and those with accessory pathway reentrant tachycardia (no. 17 patients). Moreover, the prevalence in both subsets was evaluated in the following signs and symptoms: palpitations, dyspnoea, chest pain, pulsations in the neck, significant increase in urinary output, hypotension, dizziness, near-syncope, syncope, shock, focal brain injury. From the data analysis, significantly greater prevalence of palpitations in the neck resulted in the subset of patients with reentry confined to the A-V node (no. 20 cases) compared with those suffering from reentry via accessory pathway (no. 4 cases). Moreover the arterial pressure, in A-V nodal reentrant tachycardia, showed the lowest values and the best decreases, together with the finding of a more rapid trend to decline in comparison with the accessory pathway subset. On the other hand, no significant differences could be seen about the remaining symptoms. In an attempt to provide the reliable explanation for the differences found between the 2 subsets of study, concerning both the unpleasant pulsations in the neck and the pressure decrease, we postulated a remarkable role for the length of arrhythmic circle movement. The smaller dimensions of circuit limbs, in A-V nodal reentrant tachycardia, are likely to be the principle cause of the different clinical features of 2 types of reentry. We speculate actually that in susceptible patients the critical event is most likely to be A-V functional dissociation due to early and unphysiologic activation of atria by stimulus rapidly reentrant from the bottom portion of the AV node: the simultaneous occurrence, frequent in A-V node reentry, of both, atrial and ventricular mechanical activation, would result, however, in impairment of atrial haemodynamics due to development of cannon A waves, able either to activate a vasodepressor reflex from the atria or to stimulate instantaneous release of atrial natriuretic factor in the circulation. Further studies, however, are necessary to be performed on large cases-records, to confirm our hypothesis.(ABSTRACT TRUNCATED AT 400 WORDS)

[Usefulness of a complete echographic evaluation of the atrial dimensions for the diagnosis of idiopathic atrial fibrillation]

Left atrial enlargement may occur sometimes through only the increase of the supero-inferior (S-I) diameter, with normality of the antero-posterior (A-P) and latero-medial dimensions. In this study, both the largest dimensions of the left atrium and S-I and transversal dimensions of the left atrium and S-I and transversal dimensions of the right atrium were investigated, among the 98 pts suffering from recurrent paroxysms of atrial fibrillation (FAP). On the basis of the clinical, ECGraphic and echocardiographic data, a subgroup of 78 pts has been found, with FAP reliable to heart disease, which mostly appeared as accompanying a finding of atrial enlargement--left or right or both--. The remaining 20 pts distinguished, by means of the echocardiographic findings, as following: a) "idiopathic" FAP, neither dependent on heart disease nor on atrial enlargement (no. 11 pts); b) FAP dependent on "unexplained" atrial enlargement, i.e. unreliable to definite cardiac pathology (no. 9 pts). Among the b) pts, 7 showed the only, isolated S-I dimension increased. Therefore, the determination of the all largest dimensions of the atria, in pts with recurrent FAP, appeared able to more carefully distinguish the true cases of "idiopathic" FAP.