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Background: In younger individuals, low absolute risk of cardiovascular disease (CVD) may conceal an increased risk age and relative risk of CVD. Calculation of risk age is proposed as an adjuvant to absolute CVD risk estimation in European guidelines. We aimed to compare the discriminative ability of available risk age models in prediction of CVD in rheumatoid arthritis (RA). Secondly, we also evaluated the performance of risk age models in subgroups based on RA disease characteristics. Methods: RA patients aged 30-70 years were included from an international consortium named A Trans-Atlantic Cardiovascular Consortium for Rheumatoid Arthritis (ATACC-RA). Prior CVD and diabetes mellitus were exclusion criteria. The discriminatory ability of specific risk age models was evaluated using c-statistics and their standard errors after calculating time until fatal or non-fatal CVD or last follow-up. Results: A total of 1974 patients were included in the main analyses, and 144 events were observed during follow-up, the median follow-up being 5.0 years. The risk age models gave highly correlated results, demonstrating R 2 values ranging from 0.87 to 0.97. However, risk age estimations differed > 5 years in 15-32% of patients. C-statistics ranged 0.68-0.72 with standard errors of approximately 0.03. Despite certain RA characteristics being associated with low c-indices, standard errors were high. Restricting analysis to European RA patients yielded similar results. Conclusions: The cardiovascular risk age and vascular age models have comparable performance in predicting CVD in RA patients. The influence of RA disease characteristics on the predictive ability of these prediction models remains inconclusive. © 2020 The Author(s).

Objectives: Smoking is a major risk factor for the development of both cardiovascular disease (CVD) and RA and may cause attenuated responses to anti-rheumatic treatments. Our aim was to compare disease activity, CVD risk factors and CVD event rates across smoking status in RA patients. Methods: Disease characteristics, CVD risk factors and relevant medications were recorded in RA patients without prior CVD from 10 countries (Norway, UK, Netherlands, USA, Sweden, Greece, South Africa, Spain, Canada and Mexico). Information on CVD events was collected. Adjusted analysis of variance, logistic regression and Cox models were applied to compare RA disease activity (DAS28), CVD risk factors and event rates across categories of smoking status. Results: Of the 3311 RA patients (1012 former, 887 current and 1412 never smokers), 235 experienced CVD events during a median follow-up of 3.5 years (interquartile range 2.5-6.1). At enrolment, current smokers were more likely to have moderate or high disease activity compared with former and never smokers (P < 0.001 for both). There was a gradient of worsening CVD risk factor profiles (lipoproteins and blood pressure) from never to former to current smokers. Furthermore, former and never smokers had significantly lower CVD event rates compared with current smokers [hazard ratio 0.70 (95% CI 0.51, 0.95), P = 0.02 and 0.48 (0.34, 0.69), P < 0.001, respectively]. The CVD event rates for former and never smokers were comparable. Conclusion: Smoking cessation in patients with RA was associated with lower disease activity and improved lipid profiles and was a predictor of reduced rates of CVD events. © 2019 The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Rheumatology.

International audience; Many studies of postseismic deformation following large earthquakes focus on time scales ranging from weeks to years following the main earthquake. By contrast, fewer studies have investigated the spatio-temporal distribution of postseismic deformation in the hours to days following the mainshock. Focusing on this early postseismic period is important for better understanding how stresses are redistributed on the fault immediately following the mainshock, and the relationship between the mainshock, aftershocks and postseismic slip. In this study, we estimate the spatio-temporal distribution of early afterslip following the 2016 Mw 7.8 Pedernales earthquake offshore Ecuador, with the aim of studying how its spatio-temporal distribution relates to those of the coseismic and longer-term postseismic phases. We base our analysis on time series of 30-second high-rate GPS data spanning 2 minutes to 3 days after the mainshock at 27 stations of the IGEPN and IRD joint network operating in Ecuador. We invert these time series with the Principal Component Analysis-based Inversion Method (PCAIM) [Kositsky and Avouac, 2010], incorporating a sensitivity-regulated regularization scheme. Our results suggest afterslip concentrated in regions of the fault updip of two areas that experienced peak coseismic slip, which is similar to that of afterslip estimated by inverting daily GPS time series spanning 30 days after the earthquake. However, we find a noticeable improvement in the fit of the data when a moderate amount of afterslip is also located within and downdip of the mainshock rupture area, suggesting that the coseismic and early postseismic slip episodes might partially overlap. Preliminary comparisons between the early afterslip and relocated aftershocks show good spatial agreement, consistent with the idea that the aftershocks are driven by afterslip. Finally, the equivalent moment magnitude of our models ranges from Mw 7.1 to 7.2, represents 35-50% of the geodetic moment of the 30-day afterslip model of Rolandone et al. [2017], and 9-13% of the coseismic moment released during the Mw 7.8 earthquake. These inversion results will guide our exploration of frictional properties on the megathrust, which potentially allow us to probe the physical processes that occur during the early postseismic period.

International audience; Whereas the spatial and temporal evolution of early postseismic slip (i.e., the first few hours) has been shown to be complex, we do not know well the mechanisms that control its behaviour. One pending question is to know whether or not the rate-and-state friction law is required to explain it, or if the rate-dependent friction law, traditionally used to explain afterslip observations on a day-to-month time scale, is sufficient. Based on 30-sec high-rate position time series that show the early postseismic surface displacements at 13 stations from 2.5 minutes to 3 days after the 2015 M8.3 Illapel, Chile, earthquake, we attempt to infer the frictional properties that control early postseismic slip on the fault. We invert simultaneously for the location and the amplitude of the slip patches, and for the frictional parameters that control their temporal behaviour. We use the elliptic slip patch inversion method (Vallée et Bouchon, 2004; Twardzik et al., 2012) that allows to reduce the number of unknown parameters and we solve, in particular, for the rate-and-state friction law parameters. The obtained frictional parameters are consistent with a velocity-strengthening behaviour. Our first results indicate that 1) the framework can explain the full time series, 2) the postseismic slip patches are located on the edge of the coseismic slip distribution, 3) the obtained stress drop parameter is consistent with that found for the coseismic rupture, and 4) the stiffness of the rate-and-state friction law is consistent with the size of the slip patches. We will also discuss the ability of compatible models to apply at longer postseismic timescales which would suggest a unique underlying physical process.